NL-09-1375, Enclosure 2 and 3 to NL-09-1375 - Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specification (TS) Sections 5.5.9 and TS 5.6.10: Difference between revisions

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{{#Wiki_filter:WESTINGHOUSE NON-PROPRIETARY CLASS 3 LTR-SGMP-09-109 NP-Attachment Westinqhouse Electric Company Response to NRC Request for Additional Information on H*; RAI #4;Model F and Model D5 Steam Generators August 25, 2009 Westinghouse Electric Company LLC P.O. Box 158 Madison, PA 15663© 2009 Westinghouse Electric Company LLC All Rights Reserved*Electronically approved records are authenticated in the Electronic Document Management System 1 WESTINGHOUSE NON-PROPRIETARY CLASS 3 L TR-SGMP-09-1 09 NP-Attachment Westinghouse Electric Company, Response to NRC Request for Additional Information on H*; RAI #4; Model F and Model 05 Steam Generators August 25, 2009 Westinghouse Electric Company LLC P.O. Box 158 Madison, PA 15663 © 2009 Westinghouse Electric Company LLC All Rights Reserved 'Electronically approved records are authenticated in the Electronic Document Management System LTR-SGMP-09-109 NP-Attachment Response to NRC Request for Additional Information on H*; RAI #4;Model F and Model D5 Steam Generators
{{#Wiki_filter:WESTINGHOUSE WESTINGHOUSE NON-PROPRIETARY NON-PROPRIETARY CLASS 3 LTR-SGMP-09-109 L TR-SGMP-09-1 09 NP-Attachment NP-Attachment Westinghouse Electric Company Westinqhouse                    Company, Response to NRC Request Request for Additional Additional Information on H*; RAI #4; Model F and Model  Model 05 D5 Steam Generators Generators August 25, 2009 Westinghouse Westinghouse Electric Electric Company  LLC Company LLC P.O. Box 158 158 Madison, PA 15663 Madison,        15663
                                      © 2009 Westinghouse Westinghouse Electric Company LLC     LLC All All Rights  Reserved Rights Reserved
*Electronicallyapproved records are authenticatedin the Electronic Document Management System
'Electronically approved records are authenticated in the Electronic Document Management System 1
 
LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109     NP-Attachment Response to NRC Request Request for Additional Additional Information on H*; RAI #4; Model          Model 05 Model F and Model       D5 Steam Generators Generators


==References:==
==References:==
: 1. NL-09-0547, Vogtle Electric Generating Plant License Amendment Request to Revise Technical Specification(TS)
Sections 5.5.9, "Steam Generator (SG) Program" and TS 5.6.10, "Steam Generator Tube Inspection Report for Permanent Alternate Repair Criteria,"Southern Company, May 19, 2009.2. RS-09-071, "License Amendment Request to Revise Technical Specifications (TS) for Permanent Alternate Repair Criteria," Exelon Nuclear, June 24, 2009.3. CP-200900748, Log # TXX-09075, "Comanche Peak Steam Electric Station (CPSES)Docket Nos. 50-445 and 50-446, License Amendment Request 09-007, Model D5 Steam Generator Alternate Repair Criteria," Luminant, June 8, 2009.4. SBK-L-09118, "Seabrook Station: License Amendment Request 09-03; Revision toTechnical Specification 6.7.6.k, "Steam Generator (SG) Program," for Permanent Alternate Repair Criteria (H*)," May 28, 2009.5. Vogtle Electric Generating Plant, Units 1 and 2, Request for Additional Information Regarding Steam Generator Program (TAC Nos. ME1339 and ME1340)," United StatesNuclear Regulatory Commission, July 10, 2009.6. Braidwood Station, Units 1 and 2, and Byron Station, Unit Nos. 1 and 2 -Request forAdditional Information Related to Steam Generator Permanent Alternate Repair Criteria (TAC Nos. ME1613, ME1614, ME1615, and ME1616)," United States Nuclear Regulatory Commission, July 20, 2009.7. Comanche Peak Steam Electric Station, Units 1 and 2 -Request for Additional Information Regarding the Permanent Alternate Repair Criteria License Amendment Request (TAC Nos.ME1446 and ME1447)," United States Nuclear Regulatory Commission, July 23, 2009.8. WCAP-17071-P, "H*: Alternate Repair Criteria for the Tubesheet Expansion Region in Steam Generators with Hydraulically Expanded Tubes (Model F)," Westinghouse ElectricLLC, April 2009.9. WCAP-17072-P, "H*: Alternate Repair Criteria for the Tubesheet Expansion Region in Steam Generators with Hydraulically Expanded Tubes (Model D5)," Westinghouse Electric LLC, May 2009.10. "Vogtle Electric Generating Plant, Units 1 and 2, Request for Additional Information Regarding Steam Generator Program (TAC Nos. ME1339 and ME1340)," United StatesNuclear Regulatory Commission, August 5, 2009 2


==References:==
==References:==


LTR-SGMP-09-109 NP-Attachment Response to NRC Request for Additional Information on H*; RAI #4; Model F and Model 05 Steam Generators
NL-09-0547, Vogtle Electric Generating
: 1. NL-o.9-o.547, Vogtle Electric Generating Plant License Amendment Request to Revise Technical Specification(TS)
: 1. NL-o.9-o.547,                        Generating Plant License License Amendment Request to Revise      Revise Specification(TS) Sections 5.5.9, "Steam Generator Technical Specification(TS)                                    Generator (SG)
Sections 5.5.9, "Steam Generator (SG) Program" and TS 5
(SG) Program" and TS      TS 5.6.10, 5.6.10., "Steam    Generator Generator  Tube  Inspection  Report Inspection Report for Permanent Alternate Alternate Repair Criteria,"
Southern Company, May 19, 20.0.9. 2009.
: 2. RS-09-071, RS-o.9-071, "License Amendment Amendment Request Request to Revise Revise Technical Specifications Specifications (TS) for  for Permanent Alternate Permanent    Alternate Repair Criteria," Exelon Nuclear, June 24, 2009. 20.0.9.
CP-200900748, Log # TXX-o.9o.75,
: 3. CP-2o.o.9o.o.748,              TXX-09075, "Comanche Peak Steam      Steam Electric Station (CPSES)
Docket          50-445 and 50.-446, Docket Nos. 50.-445            50-446, License Amendment Request 09-007,              Model D5 0.9-0.0.7, Model  05 Steam Generator Generator Alternate Repair Criteria," Luminant, June    June 8, 20.0.9.
2009.
: 4. SBK-L-o.9118, SBK-L-09118, "Seabrook Station: License Amendment      Amendment Request 09-03;    0.


===1.0 General===
LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109        NP-Attachment
Background on Approach and Models Discuss if the eccentricity effect on contact pressure is occurring as described.
: 4. The model model in Figure Figure 6-9 of SM-94-58, Rev.1 includes the initial applied eccentricities eccentricities (OMAX (DMAX --
It is the opinion of the NRC staff that the eccentricity effect may not be as significant as being reported by Westinghouse.
OMIN) geometry DMIN)  geometry definition definition of the model.
Response: The reference structural model for the H* calculation as described in References 8 and 9 is a 3D FEA model that utilizes the equivalent properties approach for perforated plates in accordance with Reference 6-15 of the H* WCAP reports. This model provides the tubesheet displacements that are utilized in the calculation of H*. Included in the displacement output from the 3D FEA model are the radius and depth dependent x- and y- axis displacements for the tubesheet.
: 5. The "slice" "slice" model provides provides the input for using the SF relationship (Eqn. RAI4-1). The SF is determined determined by comparing the "slice"  "slice" model results to the axisymmetric axisymmetric model results for aa TS collar and tube model at a given radius in the TS over the full thickness  thickness of the TS.
These displacements are the input to the H* integrator model that uses the inputs to calculate contact pressures based on thick-shell equations.
: 6. The result is then used to calculate calculate the reduction in contact contact pressure pressure as a function of TS  TS elevation and radius due to TS displacement elevation                              displacement and tube bore eccentricity.
The tubesheet displacements from the FEA model indicate that the tubesheet bores become eccentric after application of all thermal and pressure loads. The displacement results from the 3D FEA model are the difference between the completely unloaded case and the fully loaded case for the conditions of interest (i.e., NOP, SLB).The information from the 3D FEA model, that the tubesheet bores become eccentric, led to a question regarding continued tube-to-tubesheet contact in the eccentric tubesheet bore. The impact of tubesheet bore hole out-of-roundness (eccentricity) on the calculation of tube to-tubesheet contact pressures was originally addressed using a scale factor approach as described below and in Reference 6-15 of the H* WCAP reports. The fit developed in Reference 6-15 , a third order polynomial, was appropriate for the conditions for which it was developed but it provided physically impossible results when extrapolated significantly outside its data basis such as was the case for the SLB conditions for the Model D5 SGs.To resolve this issue, a separate model, was developed as described in Section 6.2.5 and shown in Figure 6-48 of Reference 8 and 9, to assess tube-to-tubesheet contact under the fully loaded condition (e.g., AP and thermal loading) for the small eccentricities that were calculated during the much "colder" temperature postulated SLB conditions for the Model D5 SGs than for the Model F SGs. To properly represent the tube in tubesheet condition, this model considered a tubesheet equivalent cell (the local TS material around a tubesheet bore) and a tube. To address the question if continued contact would exist between the tube and tubesheet after the tubesheet bore becomes eccentric, the tube expansion was analytically simulated to provide a condition of tube to tubesheet contact in a non-eccentric tubesheet bore. This condition was the reference condition for the subsequent loading of the model by pressure loads (thermal loads were not included) and by applying displacement boundary conditions (e-bar) to simulate the expected range of tubesheet bore eccentricity.
eccentricity. This is appropriate appropriate because the conditions for the Model because                              Model F SG and Model 05    D5 SG (NOP and FLB conditions) conditions) are within the range of datadata for which the scale scale factor relationship is applicable.
The unloaded, post-tube expansion simulation conditions of the model was the reference condition for the displacements provided in Tables 6-18 and 6-19 of the H* reports, References 8 and 9.9 LTR-SGMP-09-109 NP-Attachment
Method (WCAP-17071-P, New Method                            WCAP-17072-P):
(WCAP-17071-P, WCAP-17072-P):
: 1. The U                                          circumferential and radial ~O URR used in the calculation of the circumferential                  AD comes from a 3-D  3-D FEA model model of the lower SG complex with condition-specific condition-specific inputs inputs applied.
circumferential and radial ~O's
: 2. The circumferential                    AD's are are compared        determine the maximum ~O compared to determine                        AD that will give the maximum      reduction in contact maximum reduction          contact pressure pressure as a function of eccentricity eccentricity (e).
(e).
between ~O
: 3. The relationship between          AD and e is based on the 2-D [                  la,c,e model shown lace WCAP-17071-P and WCAP-17072-P, section 6.2.5. The model in WCAP-17071-P                                                      model is shown in Figure 6-49 of the WCAP reports. The range of eccentricityeccentricity used in this study conservatively    exceeds the values of tube bore eccentricity conservatively exceeds                                  eccentricity calculated from the the perforated perforated TS model in Section 6.2.4.
: 4. The model in Figure 6-49 of the H* WCAP reports applies boundary      boundary conditions to the  the outer outer edge edge of the tube pitch material material and does not directly directly affect the material material that is deforming in the tube and tubesheet cell.
deforming
: 5. The TS deformations deformations and tube to tubesheet contact pressure pressure results that produce the   the maximum      reduction maximum reduction in contact pressure at the minimum value of TS tube bore              bore eccentricity are then fit with a linear relationship.
eccentricity
: 6. The result of the linear relationship is used to determine determine the reduction in contact pressure between the tube and the tubesheettubesheet directly.
directly. There are no intermediate intermediate equations equations or results.
A correct prediction of contact pressure pressure loss requires the knowledge of both the proper    proper values of OMAX DMAX  and          associated OMIN associated DMIN                with  the different  pressure different pressure   and   temperature    conditions   at a given given tubesheet                  elevation as well as the value of eccentricity.
tubesheet radius and elevation                                      eccentricity. The values of OMAX  DMAX and DMIN are a OMIN                                      deflection of the tubesheet, URI a function of the radial deflection                              UR, as determined determined by the finite finite element element    analysis  model model   (which  previously previously  was a  2-D  axisymmetric  model model  of the   SG  lower lower 18


===1.0 General===
LTR-SGMP-09-109 LTR-SGMP-09-109 NP-Attachment NP-Attachment assembly assembly and at present, is aa 3-D model          model of the SG lower  lower assembly). The results from the          the "slice" model cannot be linearly  linearly scaled                temperatures because the method of super-scaled to lower temperatures position has been been shown during the development development of the current H*       H* analysis to not apply to the   the non-linear non-linear combination combination of materials and loading in the lower SG complex. This conclusion led to the development development of the 3D FEA model that is the reference          reference model for the H*      H* analysis. A      A discussion discussion of this is provided in Section Section 6.1.2 ofWCAP-17071-P of WCAP-17071-P and WCAP-17072-P.
Background on Approach and Models Discuss if the eccentricity effect on contact pressure is occurring as described.
WCAP-17072-P.
It is the opinion of the NRC staff that the eccentricity effect may not be as significant as being reported by Westinghouse.
1.3 Discussion Discussion of the Unit Cell Model    Model to Calculate Calculate Contact Pressures Pressures The "Unit Cell" model is extensively extensively discussed in Section 6.2.5 of the H*          H*WCAPs (References (References 8 and 9). The specific goal of this model was to determine      determine ifif tube to tube contact contact would remain when the tubesheet is deformed due to operating          operating loads. An equivalent tubesheet  tubesheet cell is modeled, that is, a tubesheet bore with surrounding modeled,                                                 surrounding tubesheet tubesheet material, and a tube in          in the the tubesheet tubesheet bore (see Figure 6-48 of the H*            H* WCAPs). For the primary  primary purpose of this model - to study ifif tube-to-tubesheet tube-to-tubesheet contact is present    present during the limiting tubesheet           deformations - the tubesheet deformations            the model was initialized by simulating simulating the tube expansion process. The expansion      expansion process was     was conservatively simulated conservatively    simulated by applying a low value of expansion    expansion pressure [                    1ac,e inside
Response:
                                                                                                              ]8.c.e inside the tube, resulting in initial tube to tubesheet tubesheet contact, and then removing  removing the tube expansion internal pressure. The calculated calculated dilation of the tubesheet bore due to the simulation  simulation of the tube tube expansion is ((            ] 8,C,e a,c,e inch for all models of SG considered.
The reference structural model for the H* calculation as described in References 8 and 9 is a 3D FEA model that utilizes the equivalent properties approach for perforated plates in accordance with Reference 6-15 of the H* WCAP reports. This model provides the tubesheet displacements that are utilized in the calculation of H*. Included in the displacement output from the 3D FEA model are the radius and depth dependent x-and y-axis displacements for the tubesheet.
As discussed in Section 6.2.5 of the H*              H* WCAP reports, the operating pressure loads, were              were applied applied  to the  initialized initialized  model    in  a sequential    manner,    and   the  resulting  contact  pressures pressures      were calculated when a range of displacements calculated                                displacements (termed "E-bar")    OlE-bar") were applied applied as boundary conditions to the model. Figure RA14-2          RAI4-2 shows the updated  updated sequential loading          (includes loading (includes application application  of thermal thermal    loads)    of the   model   and  relates  it it  to the steps  discussed    in Section    6.2.5 Section 6.2.5 and Tables 6-18 and 6-19 of the H*             H* WCAPs. The "E-bar"OlE-bar" values shown as the displacement displacement inputs on Tables Tables 6-18 and 6-19 in the H*                                                        displacements (in H* WCAP reports are uni-directional displacements                    (in inches) inches)  that  are  NOT    the   same    as  eccentricity eccentricity  and  also   not the   same  as  AD.  (Eccentricity
These displacements are the input to the H* integrator model that uses the inputs to calculate contact pressures based on thick-shell equations.
                                                                                                ~D. (Eccentricity is defined defined as the difference difference between the maximum    maximum and minimum diameters of a bore divided by                  by the nominal diameter of the bore. The units of eccentricity    eccentricity are inch/inch.)
The tubesheet displacements from the FEA model indicate that the tubesheet bores become eccentric after application of all thermal and pressure loads. The displacement results from the 3D FEA model are the difference between the completely unloaded case and the fully loaded case for the conditions of interest (i.e., NOP, SLB). The information from the 3D FEA model, that the tubesheet bores become eccentric, led to a question regarding continued tube-to-tubesheet contact in the eccentric tubesheet bore. The impact of tubesheet bore hole out-of-roundness (eccentricity) on the calculation of tube tubesheet contact pressures was originally addressed using a scale factor approach as described below and in Reference 6-15 of the H* WCAP reports. The fit developed in Reference 6-15 , a third order polynomial, was appropriate for the conditions for which it was developed but it provided physically impossible results when extrapolated significantly outside its data basis such as was the case for the SLB conditions for the Model 05 SGs. To resolve this issue, a separate model, was developed as described in Section 6.2.5 and shown in Figure 6-48 of Reference 8 and 9, to assess tube-to-tubesheet contact under the fully loaded condition (e.g., LlP and thermal loading) for the small eccentricities that were calculated during the much "colder" temperature postulated SLB conditions for the Model 05 SGs than for the Model F SGs. To properly represent the tube in tubesheet condition, this model considered a tubesheet equivalent cell (the local TS material around a tubesheet bore) and a tube. To address the question if continued contact would exist between the tube and tubesheet after the tubesheet bore becomes eccentric, the tube expansion was analytically simulated to provide a condition of tube to tubesheet contact in a non-eccentric tubesheet bore. This condition was the reference condition for the subsequent loading of the model by pressure loads (thermal loads were not included) and by applying displacement boundary conditions (e-bar) to simulate the expected range of tubesheet bore eccentricity.
inch/inch.) The displacement displacement inputs inputs applied applied to the unit cell model are assumed values that based on prior analyses that envelope the expected tubesheet envelope                                      displacement for all of the applicable tubesheet displacement                          applicable operating operating conditions. ItIt is  is important important to note that the unit cell model as described    described in Section 6.2.5 of the H*    H* WCAP reportsreports utilizes boundary conditions chosen to minimize    minimize the tube-to-tubesheet tube-to-tubesheet contact pressures pressures for the  the applied relative relative displacements.
The unloaded, post-tube expansion simulation conditions of the model was the reference condition for the displacements provided in Tables 6-18 and 6-19 of the H* reports, References 8 and 9. 9 LTR-SGMP-09-109 NP-Attachment While eccentricity was the specific focus of this study because of the question raised about continued tube to tubesheet contact in an eccentric condition, the analytical model naturally also provided information on tubesheet bore dilation, the diametral growth of the tubesheet bore represented by the average of the maximum and minimum diameters of the eccentric tubesheet bore. Examination of the results from this model, as is discussed further below, resulted in two significant conclusions:
displacements.
: 1. For the tubesheet bore eccentricities and dilation due to the applied loading in the limiting plants in the models of SG considered, the tube remains in contact with the tubesheet bore.2. While tubesheet bore eccentricity contributes to the reduction in contact pressure between the tube and the tubesheet, tubesheet bore dilation appears to be the principal cause of reduction of contact pressure between the tube and the tubesheet.
To interpret the results from the unit cell model    model properly, the following must be observed:
observed:
    **  To address if tube to tubesheet contact continues for all the assumed tubesheet displacements, displacements, the appropriate reference  reference condition is the initialized condition (after Step 4) of the model that simulatessimulates a tube expanded in the tubesheet bore.
19


===1.1 Discussion===
LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109          NP-Attachment
* To compare the results of the unit cell model with the 3D FEA model, the appropriate          appropriate reference condition of the unit cell model is the initial model reference                                                          model (Step 0) without the tube  tube expansion simulated and thermal loads must be included.
Figures    RAI4-3 and RA14-4 Figures RA14-3                RAI4-4 show the average  average tubesheet tubesheet bore dilation (AD)  (L10) as a function of tubesheet relative displacement displacement (E-bar) for the Model F and Model      Model D5.05. The average average tube bore dilation at zero E-bar input is the result of the temperature  temperature and pressure loadingloading of the unit cell model. Initially, application application of the displacement displacement input "E-bar" "E-bar" results in more significant hole      hole dilation, but rapidly takes on a shallower slope as the applied          applied displacement displacement increases. The        The curves are characteristically characteristically the same for the Model    Model F and Model 05  D5 steam generators generators and also for the different different operating operating conditions, NOP and SLB, for the different models of SGs.
Similarly, Figures RA14-5  RAI4-5 and RAI4-6 RA14-6 show the tubesheet tubesheet bore eccentricity eccentricity "e"  "e" as a function of tubesheet relative displacement tubesheet                  displacement (E-bar) for the Model    Model F and Model D5.            Eccentricity initially
: 05. Eccentricity        initially increases increases      with  application application    of  the  displacement displacement    boundary  condition    (E-bar)    simulating  the  load due to pressure pressure differential across across the tubesheet, but the rate of increase decays with increasing  increasing E-bar. A significant          difference is noted between significant difference                    between NOP and SLB conditions conditions at large values of E-bar. This difference reflects the fact that the uniform growth of the tube bore hole due to                              to increased      temperature overwhelms increased temperature            overwhelms the effect of application application of the displacement displacement boundary condition (E-bar) on tubesheet bore eccentricity. eccentricity. During the SLB event, the temperaturetemperature is decreased decreased        and  the  differences differences    in  DMAX OMAX    and  DMIN OMIN remain  more  significant significant    as  the  displacement displacement boundary condition is increased, although      although the rate of increase              difference between DMAX increase in the difference                    OMAX and OM    IN is reduced DMIN      reduced at some point. point.. . Eventually, at NOP conditions, the difference difference between between DMAX OMAX and DMIN OMIN  tends    to  become    decrease even though a greater decrease                        greater displacement displacement (E-bar) is applied,  applied, leading to a reduction reduction of eccentricity eccentricity "e.""e."
RAI4-7 and RA14-8 Figures RA14-7                RAI4-8 show the contact pressure as aa function of tubesheet relative              relative displacement displacement (E-bar) for the Model      Model F and Model D5      05 for both NOP and SLB conditions conditions based based on the unit cell model. As expected, both NOP and SLB contact pressure            pressure decrease decrease with increasing increasing displacement inputs, ultimately going to zero at a very large value of applied displacements.
displacement                                                                                          displacements. It    It is to be noted that the maximum displacement    displacement assumed assumed is significantly greater than would be          be predicted predicted by the 3D FEA model. Over the entire range of assumed displacement          displacement conditions, the      the SLB contact pressure pressure exceeds that for NOP conditions.
RAI4-5 summarizes Table RA14-5        summarizes the eccentricity, eccentricity, L10 AD and predicted contact pressure using the unit cell model for various values of applied                displacement (E-bar) for both the model F and Model applied displacement                                                  Model D5  05 SGs. The true    true eccentricity eccentricity ([Omax-Omin]/Onom)
([Dmax-Dmin]/Dnom) is shown for the appliedapplied displacement, E-bar.
Table RAI4-5 RA14-5 also provides aa comparisoncomparison of the L10  AD predicted by the unit cell model for the two reference reference conditions conditions notednoted above, that is, for the total L10  AD from the model withoutwithout the simulated simulated tube expansion (reference(reference step 0 in Table 6-18) and for the initialized  initialized case with the tube expansion simulated simulated (reference (reference step 4 in Table 6-18).
20


of 3D FEA Model for H* Analysis Provide table showing maximum delta diameters (total diameter distortion) and maximum eccentricities (maximum diameter minus minimum diameter) from the 3 dimensional (3-D) finite element analysis for normal operating and steam line break (SLB), for model F and D5.Response: The 3D FEA Model and its application for determining the tubesheet displacements are extensively described in Section 6 of the H* WCAP reports (References 8 and 9). It is important to note that the 3D FEA model includes the entire tubesheet complex (i.e., tubesheet, stub barrel, channelhead and divider plate) but excludes the tubes. The model utilizes an equivalent material approach from Reference 6-5 in the WCAP reports to represent the deformation of the tubesheet under the applied loading conditions (NOP, SLB/FLB).
LTR-SGMP-09-1 L TR-SGMP-09-1 09 NP-Attachment NP-Attachment Further, Table RAI4-5 RA14-5 provides aa summarysummary of contact pressures pressures between the tube and the          the tubesheet for various applied tubesheet                applied values of E-bar for the Model F and Model    Model D505 SGs. The "Modified "Modified Contact Contact Pressure" is the "Raw Contact Pressure" from the unit cell model adjusted for the actual tube expansion expansion process (([                    compared to the simulation at [
Displacements in Cartesian coordinates are calculated for these conditions at any location on the tubesheet.
                                        ]a,c,e psi compared
The displacements calculated are the changes from an unstressed, room temperature condition after all thermal and pressure loads appropriate to the operating conditions are applied. Application of a uniform temperature increase causes uniform dilation at each tubesheet bore. Application of pressure loads causes distortions in the structure due to bending. The 3D FEA model provides integrated total displacements of each tubesheet bore location.Table RAI4-1 is a summary of the maximum eccentricities and ADs for the Model F and ModelD5 limiting plants as calculated based on the UR (tubesheet radial displacement) results from the 3-D lower SG complex model.10 L TR-SGMP-09-1 09 NP-Attachment While eccentricity was the specific focus of this study because of the question raised about continued tube to tubesheet contact in an eccentric condition, the analytical model naturally also provided information on tubesheet bore dilation, the diametral growth of the tubesheet bore represented by the average of the maximum and minimum diameters of the eccentric tubesheet bore. Examination of the results from this model, as is discussed further below, resulted in two significant conclusions:
                                        ]a,c,e                                                  I] a,c,e a,c,e psi) real Model F and Model D5         geometry and more realistic operating 05 geometry                                                          pressures and operating conditions of pressures temperatures.
: 1. For the tubesheet bore eccentricities and dilation due to the applied loading in the limiting plants in the models of SG considered, the tube remains in contact with the tubesheet bore. 2. While tubesheet bore eccentricity contributes to the reduction in contact pressure between the tube and the tubesheet, tubesheet bore dilation appears to be the principal cause of reduction of contact pressure between the tube and the tubesheet.  
temperatures. For all cases of applied displacement, displacement, positive contact pressure                    between pressure remains between the tube and tubesheet. It    It should be noted that the largest value of applied          displacement (E-applied displacement        (E-bar) is well in excess excess of the displacement displacement predicted by the 30      3D FEA model.
Table Table RAI4-6 RA14-6 provides similar data to that in    in Table RAI4-5, except that the data is based on the      the 3D FEA model.
30 Comparison of Tables RA14-5 RAI4-5 and RA14-6 RAI4-6 leads to the following observations:
1.The 1.The ADs
        ~Os from the 30 3D FEA model are significantly significantly less than the corresponding corresponding ~Os ADs from the the unit cell model from the unloaded unloaded to the fully loaded                    (i.e., from step 0 to step 9) for loaded condition (Le.,                                  for both NOP and SLB conditions. This leads to the conclusion that the unit cell model displacement results and contact pressure displacement                                          predictions conservatively pressure predictions    conservatively represent the referencereference 3D FEA model results.
30
: 2. The eccentricities eccentricities from the unit cell model are generally comparable to those from the 3D                  30 FEA model. A more exact comparison is difficult      difficult based on the available data; however, itit is clear that the actual range of eccentricities eccentricities from the 30  3D FEA model was adequately adequately addressed by the unit cell model.
: 3. The method of Reference Reference 6-15 of the H*    H* WCAP report for adjusting contact pressure provides  provides acceptable acceptable results for all conditions conditions except the SLB condition for the Model      Model 05 D5 SGs The      The Reference 6-15 significantly method of Reference              significantly under-predicts under-predicts contact pressure for the ModelModel D5    05 SLB conditions.
conditions. Referring to Figure RAI4-6, the method for calculating    calculating the reduction in contactcontact pressure defined by the White Paper, when adjusted    adjusted for temperature temperature effects, shows that SLB contact contact pressure is increased increased relative to normal operating operating conditions.
conditions.
21


===1.1 Discussion===
LTR-SGMP-09-1 09 NP-Attachment LTR-SGMP-09-109      NP-Altachment RAI4-5 Table RA14-5 Eccentricity, Contact  Contact Pressure Pressure and ~D      AD Results Results from Unit Unit Cell Model Square Cell Results                Square Cell Results          Square Square Cell Results                      Square Square Cell - Average Delta D Raw Contact Raw    Contact              Modified Modified Contact        Rt*n N[2)- Rt*n cl(3)
Frc.e.*nt rinitv                    Pressure(1)                  Preslure(1)
Pressure(1)          Step        Step 9(3)          Step 4(4) - Step 9(3)
Eccentricity                                1                                              0(2) -
Ecrenricit                                                                  Sn 5tep  0(2) - Stp9'              Step 4(4) - Sten  903)
SG SG        "E bar"        NOP                    SLB            NOP            SLB          NOP          SLB          NOP              SLB          NOP              SLB "E bar"        NOP                    SLB            NOP            SLB        NOP            SLB          NOP            SLB            NOP              SLB  a,c,e a,c,e Model
    -            in in          in/in in/in                  in/in in/in            si psi    psi    psi  psi    psi          psi psi          in in              in in            in in                in F
F F
F F
D5 D5
_D5 D5
_D5 D5 D5 D5
          ~
Notes:
: 1. Accounts for expansion pressure and geometry.
: 1. Accounts for expansion pressure and geometry.
: 2. See
: 2. See Section  6.2.5 H' Section 6.2.5  H*WCAP. Step 0 is the condition of the unit-cell model prior to any modifications for tube expansion, loading, etc.
WCAP. Step 0 is the condition of the unit-cell model prior to any modifications for tube expansion, loading, etc.
: 3. See
: 3. See Section  6.2.5 H*
Section 6.2.5    WCAP. Step H' WCAP. Step 99 is the condition is the            of the condition of    unit cell model after all loading conditions have been applied.
the unit cell model after all loading conditions have been applied.
: 4. Section 6.2.5 See Section
: 4. See                H' WCAP.
6.2.5 H*
Step 4 is the initialized condition of the Unit Cell model after tube expansion has been simulated.
WCAP. Step 4 is the initialized condition of the Unit Cell model after tube expansion has been simulated.
22


of 3D FEA Model for H* Analysis Provide table showing maximum delta diameters (total diameter distortion) and maximum eccentricities (maximum diameter minus minimum diameter) from the 3 dimensional (3-D) finite element analysis for normal operating and steam line break (SLB), for model F and 05. Response:
L TR-SGMP-09-1 09 NP-Atlachment LTR-SGMP-09-109         NP-Attachment Table RAI4-6 RA14*6 Eccentricity, Eccentricity, Bore Dilation and Contact    Contact Pressure from 3D FEA Model II    Hstar Analysis
The 3D FEA Model and its application for determining the tubesheet displacements are extensively described in Section 6 of the H* WCAP reports (References 8 and 9). It is important to note that the 3D FEA model includes the entire tubesheet complex (Le., tubesheet, stub barrel, channelhead and divider plate) but excludes the tubes. The model utilizes an equivalent material approach from Reference 6-5 in the WCAP reports to represent the deformation of the tubesheet under the applied loading conditions (NOP, SLB/FLB).
_OP Ec.ce.ntricitv Eccentricity SLB Ava Hstar Analysis Avg. Cnntne.t NOP Analysis Contact Pr*.*ure.
Displacements in Cartesian coordinates are calculated for these conditions at any location on the tubesheet.
Pressure tPs Hstar Analysis Hstar No No Analysis - Avg.
The displacements calculated are the changes from an unstressed, room temperature condition after all thermal and pressure loads appropriate to the operating conditions are applied. Application of a uniform temperature increase causes uniform dilation at each tubesheet bore. Application of pressure loads causes distortions in the structure due to bending. The 3D FEA model provides integrated total displacements of each tubesheet bore location.
Nn ILoad had tn  On*r*tinn to OperatinQ SLB SLB SLB A 0D AVQ. l!.
Table RA14-1 is a summary of the maximum eccentricities and <1Ds for the Model F and Model D5 limiting plants as calculated based on the U R (tubesheet radial displacement) results from the 3-D lower SG complex model. 10 LTR-SGMP-09-109 NP-Attachment Table RAI4-1: Summary of Model D5 and Model F NOP and SLB Eccentricity Results SG Model Elev. Avg. Eccentricity Data Max. Eccentricity Data Avg. A D Max. A D Above BTS111  NOP SLB NOP SLB NOP SLB NOP SLB_ in in/in in/in in/in in/in in in in in F F F D5 D5 D5 F D5 F I________Notes: 1. BTS is Bottom of the Tubesheet The original Table RAI4-4 is provided here for convenience Eccentricity, e A C, 0o A D, 902 Plant Condition Value inch/inch inch inch a,c,e Byron SLB MAX Byron SLB MIN Byron SLB AVG Millstone SLB MAX Millstone SLB MIN Millstone SLB AVG Byron NOP MAX Byron NOP MIN Byron NOP AVG Millstone NOP MAX Millstone NOP MIN Millstone NOP AVG 11 a Ie -: T b RAI41 S ummary 0 SG Model Elev. Avg. Eccentricity Data -Above BTS(ll NOP SLB -in in/in in/in F F F 05 05 05 F 05 -Notes: 1. BTS is Bottom of the Tubesheet The original Table RA14-4 is provided here for convenience L TR-SGMP-09-1 09 NP-Altachment 0 e an 0 e an f M d I 05 d M d I F NOP d SL BE ccentrlcity R esu ts Max. Eccentricity Data Avg. Ll 0 Max. Ll 0 NOP SLB NOP SLB NOP SLB in/in in/in in in in in -c,e -Eccentricity, e Ll D, O. Ll D, 90. Plant Condition Value inch/inch inch inch a, c,e Byron SLB MAX Byron SLB MIN Byron SLB AVG Millstone SLB MAX Millstone SLB MIN Millstone SLB AVG Byron NOP MAX Byron NOP MIN Byron NOP AVG Millstone NOP MAX Millstone NOP MIN Millstone NOP AVG 11 LTR-SGMP-09-109 NP-Attachment
NOP NOP               SLB SLB        NOP NOP               SLB SLB             NOP Model and Contact Pressure SG Model                                                                                                                                      a,C,e a,c,e Reduction Model Reduction                        ,- in/in inlin            in/in in/in       psi                psi              in                in    -
F - Ref. 6-15 F       6-15 Limiting Radius Radius - F - Ref. 6-15 6-15 D5 - Ref. 6-15 05        6-15 05 D5 - White White Paper Limiting Radius - D5 Limiting            05 - Ref. 6-15 6-15 Limiting Limiting Radius - D5  05 - White Paper Paper                                                                                                    I FF - Updated Model (1)(1) 05 D5 - Updated Updated Model (1)(1)
(1):
(1): Updated    Model Results Updated MOdel              based on Iesults based    on eSIimates etimates from trom approximate  values in approximate values            element anal in finite element      y sis and analysis  and do  not reflect do not  reflect the result of a regression the result analysis.
23 23


===1.2 Discussion===
LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109          NP-Attachment RAI4-2 Figure RA14-2 Unit Cell Model Model and loading Loading Sequence Sequence (1)
(1 )          (2)                          (3)
(3)
Loading Steps:
O.
: 0. Initial Model
: 1. Initial Tube to TS gap  gap
: 2. Pressurize Pressurize tube to 16ksi
: 3. Pressurize tube to 28ksi
: 4. Release Pressure on Tube      Tube
: 5. Apply  ATV1 )
Apply ,n(l)
: 6. Apply "E-bar" "E-bar"
                                                                        ~P=[
: 7. Apply AP=[          la.c
                                                                                    ]apcse.* psii
                                                                        ~P=[
: 8. Apply AP=[          la.c
                                                                                    ]a.....* psi psi
                                                                        ~P=[
: 9. Apply AP=[          la.c
                                                                                    ]ace.* psi psi Step 0          Step 5                        Step 6-9 6-9      Notes: (1) The application of the unitunit AP  =
boP = 0          boP =
Ap= 0                        AP>
boP> 0        cell model model in support support of Tables 6-186-18 AT  = 0 boT = 0          AT= 0 6.T=                          6.T>
AT>00 and 6-19 does not include application of AT.
oft.T.
application Unexpanded Unexpanded Tube Tube Expanded Expanded Tube                Expanded Expanded Tube e=O e=0              e=O e=0                          e>O e> 0 e bar =
e    = 0        e bar =0 ebar=0                        e bar > 0 ebar>0 24


of the "Slice" Model Clarify the nature of the finite element model ("slice" model versus axisymmetric SG assembly model) used to generate the specific information in Tables 6-1, 2, and 3 (and accompanying graph entitled "Elliptical Hole Factors")
LTR-SGMP-09-109  NP-Attachment LTR-SGMP-09-1 09 NP-Attachment a,c,e RAI4-3 Figure RA14-3 Relationship between Relationship between "E-bar" "E-bar" and AD; Model Model F a,c,e a,c,e RAI4-4 Figure RA14-4 Model D5 Relationship between "E-bar" and AD; Model  05 25 25
of Reference 6-15. What loads were applied? How was the eccentricity produced in the model? (By modeling the eccentricity as part of the geometry?
By applying an axisymmetric pressure the inside of the bore?) Explain why this model is not scalable to lower temperatures.
I The difference between initial and final eccentricity included in Table RA14-2 needs to be explained.
In particular, the exclusive use of the relationship between initial eccentricity and scale factor in calculating contact pressure needs to be justified.
Resolve the apparent inconsistency between Item 4 on page 25 and the statement below Figure RA14-1 regarding how the model in Figure RA14-1 is loaded.I Response: The "slice model" is shown in Figure 6-9 of Reference 6-15 in WCAP-17071-P, WCAP-17072-P, WCAP-17091-P, and WCAP-17092-P.
The data in Tables 6-1, 6-2, and 6-3 of Reference 6-15 of the H* WCAP reports, are derived from this plane stress model ("slice model") developed in WECAN/PLUS and the contact pressure equation identified on page 6-87 of WCAP-17071-P, page 6-95 of WCAP-17072-P, page 6-91 of WCAP-17091-P and page 6-84 of WCAP-17092-P as described below.For convenience Tables 6-1, 6-2, and 6-3 of Reference 6-15 are replicated below and re-named as follows:.
Table 6-1 is renamed as Table RAI4-2, Table 6-2 is renamed as Table RAI 4-3, and Table 6-3 is renamed as Table RAI4-4.The "initial" eccentricities (defined as DMAX -DMIN) applied in the "slice" model in Table RAI4-3 and Table RAI4-4 are directly incorporated into the model geometry.
That is, the initial eccentricity is built into the model geometry.
The eccentricity values in the model were assumed values for tubesheet tube bore deformation based on engineering judgment and prior experience.
In the "slice" model analysis, the tubesheet is assumed to have a thermal expansion coefficient of zero (0) in/in/&deg;F and the tube material is assumed to have the appropriate ASME Code thermal expansion coefficient values. (The TS coefficient of thermal expansion is set to zero to provide a loading mechanism for the model. When a temperature is applied, the tube "grows" into the tubesheet collar. The temperature difference applied to the tube in the "slice" model was 500&deg;F, for a total tube temperature of 570&deg;F. [Applied 500&deg;F + 70&deg;F assumed room temperature]).
The sole purpose of the development of the "slice" model was to provide a sensitivity study to relate the effects of assumed eccentricity (DMAx -DMIN) conditions to contact pressures from which the contact pressure ratios were developed.
No attempt was made to 12 LTR-SGMP-09-109 NP-Attachment


===1.2 Discussion===
LLTR-SGMP-09-109  NP-Attachment TR-SGMP-09-1 09 NP-Attachment a,c,e a,c,e Figure RA14-5 Figure RAI4-5 Relationship between between liE-bar" "E-bar" and Eccentricity Eccentricity "e"; Model F a,c,e Figure Figure RAI4-6 RA14-6 Relationship Relationship between between "E-bar" liE-bar" and and Eccentricity Eccentricity "e"; Model D5 "e"; Model  05 26 26


of the "Slice" Model Clarify the nature of the finite element model ("slice" model versus axisymmetric SG assembly model) used to generate the specific information in Tables 6-1,2, and 3 (and accompanying graph entitled "Elliptical Hole Factors")
LLTR-SGMP-09-109 TR-SGMP-09-1 09 NP-Attachment NP-Attachment a,c,e RAI4-7 Figure RA14-7 Relationship between Relationship between "E-bar" liE-bar" and Contact Pressure; Pressure; Model Model F a,c,e a,c,e Figure RA14-8 Figure RAI4-8 "E-bar" and Contact Relationship between liE-bar"       Contact Pressure; Model 05 D5 27 27
of Reference 6-15. What loads were applied? How was the eccentricity produced in the model? (By modeling the eccentricity as part of the geometry?
By applying an axisymmetric pressure the inside of the bore?) Explain why this model is not scalable to lower temperatures.
The difference between initial and final eccentricity included in Table RA14-2 needs to be explained.
In particular, the exclusive use of the relationship between initial eccentricity and scale factor in calculating contact pressure needs to be justified.
Resolve the apparent inconsistency between Item 4 on page 25 and the statement below Figure RA14-1 regarding how the model in Figure RA14-1 is loaded. Response:
The "slice model" is shown in Figure 6-9 of Reference 6-15 in WCAP-17071-P, WCAP-17072-P, WCAP-17091-P, and WCAP-17092-P.
The data in Tables 6-1, 6-2, and 6-3 of Reference 6-15 of the H* WCAP reports, are derived from this plane stress model ("slice model") developed in WECAN/PLUS and the contact pressure equation identified on page 6-87 of WCAP-17071-P, page 6-95 of WCAP-17072-P, page 6-91 ofWCAP-17091-P and page 6-84 ofWCAP-17092-P as described below. For convenience Tables 6-1,6-2, and 6-3 of Reference 6-15 are replicated below and re-named as follows:.
Table 6-1 is renamed as Table RAI4-2, Table 6-2 is renamed as Table RAI4-3, and Table 6-3 is renamed as Table RAI4-4. The "initial" eccentricities (defined as DMAX -D M1N) applied in the "slice" model in Table RA14-3 and Table RA14-4 are directly incorporated into the model geometry.
That is, the initial eccentricity is built into the model geometry.
The eccentricity values in the model were assumed values for tubesheet tube bore deformation based on engineering judgment and prior experience.
In the "slice" model analysis, the tubesheet is assumed to have a thermal expansion coefficient of zero (0) in/infOF and the tube material is assumed to have the appropriate ASME Code thermal expansion coefficient values. (The TS coefficient of thermal expansion is set to zero to provide a loading mechanism for the model. When a temperature is applied, the tube "grows" into the tubesheet collar. The temperature difference applied to the tube in the "slice" model was 500&deg;F, for a total tube temperature of 570&deg;F. [Applied 500&deg;F + 70&deg;F assumed room temperature)).*
The sole purpose of the development of the "slice" model was to provide a sensitivity study to relate the effects of assumed eccentricity (DMAX -D M1N) conditions to contact pressures from which the contact pressure ratios were developed.
No attempt was made to 12 LTR-SGMP-09-109 NP-Attachment reproduce the contact pressures that would be calculated by the 2-D axisymmetric model that was previously used to develop the tubesheet displacements.
The "final" eccentricity (DMAX -DMIN) values in Table RAI4-3 and Table RAI4-4 were also determined using the "slice model": The final eccentricity values are the (DMAx- DMIN) results of applying the loading conditions on the slice model: The loads applied to the "slice" model were thermal loads only as follows: 0 psig -Primary Side Pressure 0 psig -Secondary Side Pressure 500 'F- Tubesheet AT 500 OF- Channel Head AT 500 OF- Shell AT As discussed in Reference 6-15, Table RAI4-3 was constructed using the displacement results from the plane stress model analysis for the elliptical holes along with the contact pressure equations.
The effective change in hole diameter was calculated as follows using a series of assumed scale factors: a,c,e a I1 (RAI4-1)The ADMAx and ADMIN were taken from the radial and circumferential change in tube bore diameter in the "slice" model.The corresponding contact pressure for each scale factor was then determined as follows: a,c,e (RAI4-2)K I" Equation RAI4-2 is a generic representation of how tube to tubesheet contact pressure is calculated in the H* integrator spreadsheet analysis.
The equation is equivalent to the equation for P2 shown on page 6-87 in WCAP-17071-P, page 6-95 in WCAP-17072-P, page 6-91 in WCAP-10791-P and page 6-84 in WCAP-17092-P.
The scale factors for a given input eccentricity in Table RAI 4-3 result in contact pressure ratios using the thick shell equations that are equal to the contact pressure ratios calculated using the"slice" model for initial eccentricities (defined as DMAX -DMIN) equivalent to 0.0002, 0.0004,0.0006 and 0.0008 inches, respectively, compared to the contact pressures for a circular hole (DMAx -DMIN =0). These scale factors are identified in bold print in Table RAI4-3. The data for the scale factors as a function of "initial" eccentricity was fit by a third order polynomial equation provided on page 6-85 of WCAP-17071-P and page 6-86 of WCAP-17072-P.
13 LTR-SGMP-09-109 NP-Attachment reproduce the contact pressures that would be calculated by the 2-D axisymmetric model that was previously used to develop the tubesheet displacements.
The "final" eccentricity (DMAX -D M1N) values in Table RA14-3 and Table RA14-4 were also determined using the "slice model": The final eccentricity values are the (DMAX -D M1N) results of applying the loading conditions on the slice model: The loads applied to the "slice" model were thermal loads only as follows: o psig -Primary Side Pressure o psig -Secondary Side Pressure 500 &deg;F_ Channel Head T 500 &deg;F_ Shell T As discussed in Reference 6-15, Table RA14-3 was constructed using the displacement results from the plane stress model analysis for the elliptical holes along with the contact pressure equations.
The effective change in hole diameter was calculated as follows using a series of assumed scale factors: a,c,e [ The and ilDMIN were taken from the radial and diameter in the "slice" model. ] (RAI4-1) circumferential change in tube The corresponding contact pressure for each scale factor was then determined as follows: [ ] a,c,' (RAI4-2) bore Equation RA14-2 is a generic representation of how tube to tubesheet contact pressure is calculated in the H* integrator spreadsheet analysis.
The equation is equivalent to the equation for P2 shown on page 6-87 in WCAP-17071-P, page 6-95 in WCAP-17072-P, page 6-91 in WCAP-10791-P and page 6-84 in WCAP-17092-P.
The scale factors for a given input eccentricity in Table RAI 4-3 result in contact pressure ratios using the thick shell equations that are equal to the contact pressure ratios calculated using the "slice" model for initial eccentricities (defined as DMAX -D M1N) equivalent to 0.0002, 0.0004, 0.0006 and 0.0008 inches, respectively, compared to the contact pressures for a circular hole (DMAX -DMIN =0). These scale factors are identified in bold print in Table RAI4-3. The data for the scale factors as a function of "initial" eccentricity was fit by a third order polynomial equation provided on page 6-85 of WCAP-17071-P and page 6-86 of WCAP-17072-P.
13 LTR-SGMP-09-109 NP-Attachment Based on a review of Table RAI4-3 and Table RAI4-4, the scale factor [ ]a,c,e is the appropriate scale factor for calculating a reduction factor for contact pressure of [ I ace associated with an initial eccentricity of [ ] a,c,e ((DMx -DMIN)/ [ ]a,c,e inch) from the"slice" model. The scale factor of [ ]a,c,e relates to a contact pressure reduction factor of]5.c.e and corresponds to an initial eccentricity of [ ] ,c,e inch, and so forth.The "final eccentricity" values corresponding to the same scale factors highlighted in bold in Table RAI 4-3 (and Table RAI4-4) are not used in determining the reduction in contact pressure because the resulting third order polynomial relationship between scale factor and eccentricity is bounded by the relationship for "initial eccentricity", i.e., the resultant scale factors, and hence the reduction in contact pressure due to eccentricity, would be less using the third order fit resulting from the "final" eccentricity values from Table RAI 4-3. For example, for an eccentricity of 1 E-3 in/in, the scale factor is [ I a,c,e as compared to [ ]ace for the trend line associated with the "initial" eccentricity results. Figure RAI 4-1 illustrates this. This figure shows a comparison of the trend line analysis for "initial" eccentricity and "final" eccentricity.
Referring to Equation RAI 4-1, larger scale factors result in a greater reduction in contact pressure due to eccentricity.
Table RAI4-2 Reproduced Table 6-1 of Reference 6-15 Sleeve O.D. Tube O.D.Eccentricity Delta"'T(S inm'h I A wnrnr p(1) i fin(3) r n3it (1) (2) A, (1) iD &#xfd; (3) a,c,e 0.0000 0.0002 0.0004 0.0006 0.0008 L _____Notes: This table-ts developed from the model shown in Figure RAI4-1, below.1. The units of these columns are stress in psi.2. The "delta" in this table refers to the maximum deviation from a constant value of the mean linearized radial stress around the tube bore.3. The ratio is calculated by dividing the contact pressure between the tube and the tubesheet at a given eccentricity by the contact pressure between the tube and the tubesheet in a round tube bore (e=0.0). For example, the ratio of [ ] ".c.e calculated in Table 6-1 is a ratio of the average contact pressure at an eccentricity of 0.0002 in of [ ]Oa,c, psi divided by the average contact pressure at an eccentricity of[L ] ..... psi.14 L TR-SGMP-09-1 09 NP-Attachment Based on a review of Table RA14-3 and Table RA14-4, the scale factor [ ]a,c,e is the appropriate scale factor for calculating a reduction factor for contact pressure of [ ] a,c,e associated with an initial eccentricity of [ ] a,c,e ((DMAX -DMIN)/ [ ]a,c,e inch) from the "slice" model. The scale factor of [ ]a,c,e relates to a contact pressure reduction factor of [ ]a.c.e and corresponds to an initial eccentricity of [ ]a,c,e inch, and so forth. The "final eccentricity" values corresponding to the same scale factors highlighted in bold in Table RAI 4-3 (and Table RAI4-4) are not used in determining the reduction in contact pressure because the resulting third order polynomial relationship between scale factor and eccentricity is bounded by the relationship for "initial eccentricity", i.e., the resultant scale factors, and hence the reduction in contact pressure due to eccentricity, would be less using the third order fit resulting from the "final" eccentricity values from Table RAI 4-3. For example, for an eccentricity of 1 E-3 in/in, the scale factor is [ ] a,c,e as compared to [ ]a,c,e for the trend line associated with the "initial" eccentricity results. Figure RAI 4-1 illustrates this. This figure shows a comparison of the trend line analysis for "initial" eccentricity and "final" eccentricity.
Referring to Equation RAI 4-1, larger scale factors result in a greater reduction in contact pressure due to eccentricity.
Table RAI4-2 Reproduced Table 6-1 of Reference 6-15 Sleeve 0.0. Tube 0.0. Eccentricity Oelta(1) lL) (inch) -Average(1)
Ratio(3) Oelta(1) (2) Average(1)
Ratio(3) a,c,e 0.0000 0.0002 0.0004 0.0006 0.0008 Notes: This table IS developed from the model shown in Figure RA14-1, below. 1. The units of these columns are stress in psi. 2. The "delta" in this table refers to the maximum deviation from a constant value of the mean linearized radial stress around the tube bore. 3. The ratio is calculated by dividing the contact pressure between the tube and the tubesheet at a given eccentricity by the contact pressure between the tube and the tubesheet in a round tube bore (e=O.O). For example, the ratio of [ 1 8.C ** calculated in Table 6-1 is a ratio of the average contact pressure at an eccentricity of 0.0002 in of[ ]",c .* psi divided by the average contact pressure at an eccentricity of [ J8.C ** psi. 14 LTR-SGMP-09-109 NP-Attachment Table RAI4-3 Reproduction of Table 6-2 of Reference 6-15 Primary Pressure 0 p Secondary Pressure 0 p Tubesheet Delta T 500 0 Shell Delta T 500 Channel Head Delta T 500 o Sleeve OD Delta D ir Tube ID Delta D [ ir Tube OD Delta D (Thermal)
[c. i Sleeve/Tube Interaction Coefficients
[ ]-,c Tube/Tubesheet Interaction Coefficients
[ ] 'll" sig sig F F F I ,e Eccentricity (1) (2) (3) (4) (5 6 Final Hole Delta Hole Delta S/T T/TS Initial (inch) Max/Min D (0 Deg) D (90 Contract Contact Ratio (inch) Combination Dg rsuePesr a,c,e Deg) Pressure Pressure 0.0000 Minimum Average Maximum 0.0002 Minimum Averae a,e Maximum 0.0004 Minimum Avera e a, Maximum a,c,e 15 L TR-SGMP-09-1 09 NP-Attachment Table RAI4-3 Reproduction of Table 6-2 of Reference 6-] 5 Primary Pressure 0 psig Secondary Pressure 0 psig Tubesheet Delta T 500 of Shell Delta T 500 OF Channel Head Delta T 500 OF Sleeve OD Delta D ]a,c,e in Tube ID Delta D ] a,c,s in Tube OD Delta D (Thermal)
] a,c,e in SleevelTube Interaction Coefficients
] a,c,a Tube/Tubesheet Interaction Coefficients
] a,c,a Eccentricity (1 ) (2) (3) (4) (5) 76) Final Hole Delta Hole Delta SIT TITS Initial (inch) Max/Min D (0 Deg) D (90 Contract Contact Ratio (inch) -,c,e Deg) Pressure Pressure 0.0000 Minimum -a,c,e Average Maximum 0.0002 Minimum Avera e a, ,9 ,...:...:." '---Maximum 0.0004 Minimum e a, ,e '---Maximum L--L--15 LTR-SGMP-09-109 NP-Attachment Table RAI4-3 (Cont'd.)Eccentricity a,c,e (1) (2) (3) (4) (5) (6)0.0006 F Minimum F A_.vveragea'c'e
--Maximunm 0.0008 Minimum Average a,c Maximum Note: The values in Bol-d identify the source data for Table RAI4-3 a,c,e Table RAI4-4 Reproduction of Table 6-3 of Reference 6-15 Nominal Hole Diameter F- Eccentricitv(1)I a,c,e Initial Initial Pressure Delta (in/in) Ratio Dia Final Max/Min (in) (in/in) Factor 0.0000 0.0002 0.0004 0.0006 0.0008 a,c,e I kI ) I Isb values are the Vaalues ir Inial anid final eccentricity from Table RAI4-2 are divided by the nominal tubesheet hole diameter [ ]a,c,e a,c,e 16 L TR-SGMP-09-1 09 NP-Attachment Table RAI4-3 (Cont'd.)
Eccentricity a,c,e (1) r-(2) (3) (4) r--0.0006 Minimum Averagea,c,e Maximum 0.0008 Minimum Average a,c Maximum Note: The values in Bciid identify the source data for Table RA14-3 Table RAI4-4 Reproduction of Table 6-3 of Reference 6-15 Nominal Hole Diameter 1 a,c,e Eccentricity(1)
Initial Initial Pressure Delta (in/in) Ratio Dia Final Max/Min (in) (in/in) Factor 0.0000 0.0002 0.0004 0.0006 0.0008 , ., (1) These values are the values for Initial and final eccentricity from Table RA14-2 are divided by the nominal tubesheet hole diameter [ t,c,e (5) (6) _ a,c,e -a,c,e 16 LTR-SGMP-09-109 NP-Attachment a,c,e.Figure RAI4-2: Scale Factor Comparison (Initial versus Final Eccentricity)
The method for calculating the contact pressure for using the "old" method for the Model F SGs (all plant conditions) and the Model D5 SGs (NOP and FLB conditions) and the "new" method for calculating the contact pressure the Model D5 SGs only (SLB conditions) are described below: Old Method (Reference 6-15): 1. The UR used in the calculation of the circumferential and radial AD is based on the linearly scaled 2D axisymmetric FEA model (3-D model for the current H* analysis) of the lower SG complex 2. The circumferential and radial AD's are used in the scale factor (SF) equation to determine the ADhole (see equation RAI4-1) that is used to determine the reduction in contact pressure as a function of eccentricity (e), equation RAI4-2.3. The relationship between 11D and e is based on the 2-D plane model shown in Figure 6-9 of SM-94-58, Rev.1.17 LTR-SGMP-09-109 NP-Attachment a,c,e Figure RAI4;..2:
Scale Factor Comparison (Initial versus Final Eccentricity)
The method for calculating the contact pressure for using the "old" method for the Model F SGs (all plant conditions) and the Model D5 SGs (NOP and FLB conditions) and the "new" method for calculating the contact pressure the Model D5 SGs only (SLB conditions) are described below: Old Method (Reference 6-15): 1. The U R used in the calculation of the circumferential and radial .1D is based on the linearly scaled 2D axisymmetric FEA model (3-D model for the current H* analysis) of the lower SG complex 2. The circumferential and radial .1D's are used in the scale factor (SF) equation to determine the .1D ho1e (see equation RAI4-1) that is used to determine the reduction in contact pressure as a function of eccentricity (e), equation RAI4-2. 3. The relationship between 11 D and e is based on the 2-D plane model shown in Figure 6-9 of SM-94-58, Rev.1. 17 LTR-SGMP-09-109 NP-Attachment
: 4. The model in Figure 6-9 of SM-94-58, Rev.1 includes the initial applied eccentricities (DMAX -DMIN) geometry definition of the model.5. The "slice" model provides the input for using the SF relationship (Eqn. RAI4-1). The SF is determined by comparing the "slice" model results to the axisymmetric model results for a TS collar and tube model at a given radius in the TS over the full thickness of the TS.6. The result is then used to calculate the reduction in contact pressure as a function of TS elevation and radius due to TS displacement and tube bore eccentricity.
This is appropriate because the conditions for the Model F SG and Model D5 SG (NOP and FLB conditions) are within the range of data for which the scale factor relationship is applicable.
New Method (WCAP-17071-P, WCAP-17072-P):
: 1. The UR used in the calculation of the circumferential and radial AD comes from a 3-D FEA model of the lower SG complex with condition-specific inputs applied.2. The circumferential and radial AD's are compared to determine the maximum AD that will give the maximum reduction in contact pressure as a function of eccentricity (e).3. The relationship between AD and e is based on the 2-D [ lace model shown in WCAP-17071-P and WCAP-17072-P, section 6.2.5. The model is shown inFigure 6-49 of the WCAP reports. The range of eccentricity used in this study conservatively exceeds the values of tube bore eccentricity calculated from the perforated TS model in Section 6.2.4.
: 4. The model in Figure 6-49 of the H* WCAP reports applies boundary conditions to the outer edge of the tube pitch material and does not directly affect the material that is deforming in the tube and tubesheet cell.5. The TS deformations and tube to tubesheet contact pressure results that produce the maximum reduction in contact pressure at the minimum value of TS tube bore eccentricity are then fit with a linear relationship.
: 6. The result of the linear relationship is used to determine the reduction in contact pressure between the tube and the tubesheet directly.
There are no intermediate equations or results.A correct prediction of contact pressure loss requires the knowledge of both the proper values of DMAX and DMIN associated with the different pressure and temperature conditions at a given tubesheet radius and elevation as well as the value of eccentricity. The values of DMAX and DMIN are a function of the radial deflection of the tubesheet, UR, as determined by the finite element analysis model (which previously was a 2-D axisymmetric model of the SG lower 18 LTR-SGMP-09-109 NP-Attachment
: 4. The model in Figure 6-9 of SM-94-58, Rev.1 includes the initial applied eccentricities (OMAX -OMIN) geometry definition of the model. 5. The "slice" model provides the input for using the SF relationship (Eqn. RAI4-1). The SF is determined by comparing the "slice" model results to the axisymmetric model results for a TS collar and tube model at a given radius in the TS over the full thickness of the TS. 6. The result is then used to calculate the reduction in contact pressure as a function of TS elevation and radius due to TS displacement and tube bore eccentricity.
This is appropriate because the conditions for the Model F SG and Model 05 SG (NOP and FLB conditions) are within the range of data for which the scale factor relationship is applicable.
New Method (WCAP-17071-P, WCAP-17072-P):
: 1. The U R used in the calculation of the circumferential and radial comes from a 3-D FEA model of the lower SG complex with condition-specific inputs applied. 2. The circumferential and radial are compared to determine the maximum that will give the maximum reduction in contact pressure as a function of eccentricity (e). 3. The relationship between and e is based on the 2-D [ la,c,e model shown in WCAP-17071-P and WCAP-17072-P, section 6.2.5. The model is shown in Figure 6-49 of the WCAP reports. The range of eccentricity used in this study conservatively exceeds the values of tube bore eccentricity calculated from the perforated TS model in Section 6.2.4. 4. The model in Figure 6-49 of the H* WCAP reports applies boundary conditions to the outer edge of the tube pitch material and does not directly affect the material that is deforming in the tube and tubesheet cell. 5. The TS deformations and tube to tubesheet contact pressure results that produce the maximum reduction in contact pressure at the minimum value of TS tube bore eccentricity are then fit with a linear relationship.
: 6. The result of the linear relationship is used to determine the reduction in contact pressure between the tube and the tubesheet directly.
There are no intermediate equations or results. A correct prediction of contact pressure loss requires the knowledge of both the proper values of OMAX and OMIN associated with the different pressure and temperature conditions at a given tubesheet radius and elevation as well as the value of eccentricity.
The values of OMAX and OMIN are a function of the radial deflection of the tubesheet, URI as determined by the finite element analysis model (which previously was a 2-D axisymmetric model of the SG lower 18 LTR-SGMP-09-109 NP-Attachment assembly and at present, is a 3-D model of the SG lower assembly).
The results from the"slice" model cannot be linearly scaled to lower temperatures because the method of super-position has been shown during the development of the current H* analysis to not apply to the non-linear combination of materials and loading in the lower SG complex. This conclusion led to the development of the 3D FEA model that is the reference model for the H* analysis.
A discussion of this is provided in Section 6.1.2 of WCAP-17071-P and WCAP-17072-P.


===1.3 Discussion===
LTR-SGMP-09-109 LTR-SGMP-09-109 NP-Attachment NP-Attachment 2.0 Comparison Comparison of Slice Model and Unit Cell Model                        Results Model Results The basis basis for applying applying the correlation correlationfor  for scale factor factor outside outside an "eccentricity" "eccentricity"range range of of between 1   1E-3 E-3  to  IE-4  inch 1E-4 inch  in  the  calculation calculation      of contact contact pressure pressure needs to be further explained. Values for displacements explained. Values            displacements included included in Table 6-18 (of WCAP-17071)
WCAP-17071) suggest that contact that  contact pressure pressuremay be lost at      at displacement displacement ranging ranging between 1    1E-3 E-3 in to 1 1E-4 in.
E-4 in.


of the Unit Cell Model to Calculate Contact Pressures The "Unit Cell" model is extensively discussed in Section 6.2.5 of the H* WCAPs (References 8 and 9). The specific goal of this model was to determine if tube to tube contact would remain when the tubesheet is deformed due to operating loads. An equivalent tubesheet cell is modeled, that is, a tubesheet bore with surrounding tubesheet material, and a tube in the tubesheet bore (see Figure 6-48 of the H* WCAPs). For the primary purpose of this model -to study if tube-to-tubesheet contact is present during the limiting tubesheet deformations
===Response===
-the model was initialized by simulating the tube expansion process. The expansion process was conservatively simulated by applying a low value of expansion pressure [ a 1 c,e inside the tube, resulting in initial tube to tubesheet contact, and then removing the tube expansion internal pressure.
Interpretation of the displacements Interpretation          displacements noted in    in Table 6-18 of the WeAPWCAP reports was clarified in the    the prior response, Section 1.3. 1.3. The values noted in      in the column titled "Displacement Total" refer to       to the condition of the unit cell model after Step 4 <;>f        of the loading sequence sequence (See Figure RAI4-2).
The calculated dilation of the tubesheet bore due to the simulation of the tube expansion is [ ] a,c,e inch for all models of SG considered.
When the true reference reference condition (Step 0) for total displacement displacement is considered, the values of total displacement displacement are significantly largerlarger as noted previously.
As discussed in Section 6.2.5 of the H* WCAP reports, the operating pressure loads, were applied to the initialized model in a sequential manner, and the resulting contact pressures were calculated when a range of displacements (termed "E-bar") were applied as boundary conditions to the model. Figure RAI4-2 shows the updated sequential loading (includes application of thermal loads) of the model and relates it to the steps discussed in Section 6.2.5 and Tables 6-18 and 6-19 of the H* WCAPs. The "E-bar" values shown as the displacement inputs on Tables 6-18 and 6-19 in the H* WCAP reports are uni-directional displacements (in inches) that are NOT the same as eccentricity and also not the same as AD. (Eccentricity is defined as the difference between the maximum and minimum diameters of a bore divided by the nominal diameter of the bore. The units of eccentricity are inch/inch.)
Westinghouse agrees that the derivation of the fit in Westinghouse                                                    in Reference Reference 6-15 is non-intuitive non-intuitive and limited limited in its application.
The displacementinputs applied to the unit cell model are assumed values that based on prior analyses that envelope the expected tubesheet displacement for all of the applicable operating conditions. It is important to note that the unit cell model as described in Section 6.2.5 of the H* WCAP reports utilizes boundary conditions chosen to minimize the tube-to-tubesheet contact pressures for the applied relative displacements.
application. However, the results of applying the fit described                      reference 6-15 are described in reference acceptable acceptable relative to a best case finite elementelement model (unit cell with thermal and ~P      AP loading) for the reasons reasons described below.
To interpret the results from the unit cell model properly, the following must be observed:* To address if tube to tubesheet contact continues for all the assumed tubesheet displacements, the appropriate reference condition is the initialized condition (after Step 4) of the model that simulates a tube expanded in the tubesheet bore.19 LTR-SGMP-09-109 NP-Attachment assembly and at present, is a 3-D model of the SG lower assembly).
Westinghouse Westinghouse also agrees that the fit that describes  describes the reduction in contact pressure for the       the steam steam  line  break  condition  in the   Model    D5 05  White    Paper  does  not account account    for the reduction in reduction contact contact pressure due to tube bore dilation in the same      same manner as the fit described described in Reference Reference 6-15. The results of using the fit described described in Reference Reference 6-15 also match match the expected expected trend from aa best case finite element model.
The results from the "slice" model cannot be linearly scaled to lower temperatures because the method of position has been shown during the development of the current H* analysis to not apply to the non-linear combination of materials and loading in the lower SG complex. This conclusion led to the development of the 3D FEA model that is the reference model for the H* analysis.
model. See the response to b.4 below for more details.
A discussion of this is provided in Section 6.1.2 ofWCAP-17071-P and WCAP-17072-P.
A series of tubesheet tube bore eccentricities eccentricities were applied to the tubesheet cell model       model and combined combined    with  different pressure    and  temperature temperature      loads. The  average,    maximum maximum    and  minimum minimum values of the tube-to-tubesheet tube-to-tubesheet (TITS)
(TITS) contact pressures pressures around the circumference circumference of the tubetube were reported. The valuesvalues of tubesheet tubesheet relative relative displacement,                      temperature that displacement, pressure and temperature were used in the analysis are summarized summarized in the table below.
Input Conditions for Unit Cell Model Input (no correlation implied)
Internal Internal            Temperature Temperature e              Pressure              Difference Difference in in               AP,
                                                ~P, psi                AT,OF
                                                                        ~T, OF  ace a,c,e 0.00                                            -
2.0E-04 2.0E-04 4.OE-04 4.0E-04 28


===1.3 Discussion===
LTR-SGMP-09-109          NP-Attachment LTR-SGMP-09-109 NP-Attachment Normal operating operating (Nap)(NOP) conditions in the Model      Model 05  D5 and Model F steam generators are represented by a AP of ((
represented                              ]a,c,e psi and a AT of ((          ] a,c,e of.
OF. Main steam line break (SLB) .
conditions in the Model D5      05 are represented represented by a AP of ((                    " psi and a AT of [ )) a,c,e of.
                                                                                      )) a,c,e                                    OF.
The value of AP in    in the  tubesheet      cell  can change change    as  a function      of  elevation    in the tubesheet due  due to the distribution of crevice pressure. The results of the study include              include the data for a depth ratio      ratio of 0.9 which is an elevation elevation roughly 2 inches below the top of the tubesheet. The values of AP                            AP represented represented    in  this  study  account account for the region of interest near the top of the tubesheet          tubesheet where where the maximum maximum eccentricity eccentricity in  in the tubesheet tubesheet is expected expected and where the crevice            crevice fluid is transitioning from the crevice  crevice conditions to the secondary secondary side fluid conditions. The region roughly 2 inches inches below the top of the tubesheet  tubesheet is also where a significant portion of the TITS              T/TS contact pressure develops develops so itit is a good indicator indicator of trends in the effect that different operating    operating conditions conditions have on the contact pressure.
The original original results in section                    WCAP-1 7071-P were used to verify that the reduction in section 6.2.5 of WCAP-17071-P                                                                    in T/TS contact pressure TITS            pressure as a function of tubesheet tubesheet tube bore eccentricity eccentricity was appropriate appropriate for thethe Model Model F SG. The original relationship that is used to define the reduction            reduction in TITST/TS contact pressure as'a function of eccentricity eccentricity is described described in section 6.3 of WCAP 17071-P        17071-P and and WCAP 17072-P. However, the result of applying the fit described          described in section 6.3 to the Model D5              05 SG during during SLB was shown to be inconsistent with the expected trend from the more detailed analysis described described in  in section section 6.2.5. The results of section 6.2.5 were then used to define a new relationship  between relationship between        the  reduction in TITS T/TS contact pressure and tube bore eccentricity. eccentricity. This This
\
new relationship is described described in the Model D5      05 White Paper (Reference (Reference 12). Figure RA14-8    RAI4-8 shows the result of applying the new        new relationship to the Model D5        05 SLB conditions          (i.e., White conditions (i.e.,      White rd Paper Paper    results,  Reference Reference      12)  in comparison comparison      with  the  results  from    the old  3 3 rd  order  polynomial relationship.
relationship. Because Because the tubesheet tubesheet temperature induced hole dilation,                  potentially the most dilation, potentially significant significant factor in  in contact pressure reduction, was not considered in the Model                Model D5  05 condition condition results, a third curve curve    was  added    to  the  figure titled  "Model D5 05 FEA trend." This curve represents    represents the most accurate accurate calculation of the contact pressure  pressure ratio.
Figure Figure RAI4-9 RA14-9 shows the contact pressure    pressure ratio (PCSLB/PCNoP)
(PCsLB/PCNoP) as a function of tubesheet relative displacement, displacement, E-bar. ItIt is clear from Figure RA14-9      RAI4-9 that the results of using the old fit for the Model 05  D5 SLB are inconsistent inconsistent with the more detailed detailed analysis. At SLB conditions, the          the tubesheet bore dilation is relatively relatively larger than at Nap  NOP conditions conditions due to the increased  increased bending of the TS and decreased decreased thermal expansion. Therefore,    Therefore, it  it is expected that the T/TS    TITS contact pressure pressure ratio should increaseincrease by aa factor of at least [ ]a,c,e  ]a,c,e (see Figure RAI4-9)
RAI4-9) when going from NOP Nap to SLB. It    It is also expected expected that the tube to tubesheet contact pressure        pressure should decrease with increasing decrease          increasing tube bore eccentricity.
eccentricity. The H*  H* results using the old fit for the Model D5            05 clearly do not follow either expectation expectation from the detailed analysis. However, when the new fit                      fit results are applied applied to the H*  H* calculation calculation process the relationship relationship between between TITS contact pressure  pressure in the Model Model 05D5 is much more reasonable and follows the expected          expected trend from the more detailed analysis.
detailed The Model F H*  H* contact pressure results, using the old fit, are well within the range predicted              predicted by  by the more detailed detailed analysis in    in section 6.2.5 and the additional work described      described in this RAI response. See Figure          RAI 4-10 below. This means that the old fit is appropriate Figure RA14-10                                                          appropriate to use for the  the 29


of the Unit Cell Model to Calculate Contact Pressures The "Unit Cell" model is extensively discussed in Section 6.2.5 of the H* WCAPs (References 8 and 9). The specific goal of this model was to determine if tube to tube contact would remain when the tubesheet is deformed due to operating loads. An equivalent tubesheet cell is modeled, that is, a tubesheet bore with surrounding tubesheet material, and a tube in the tubesheet bore (see Figure 6-48 of the H* WCAPs). For the primary purpose of this model -to study if tube-to-tubesheet contact is present during the limiting tubesheet deformations
LLTR-SGMP-09-109 TR-SGMP-09-1 09 NP-Attachment NP-Attachment NOP and SLB conditions and the NOP condition in the Model Model F NOP Model                                                                     05 SG. The results of Model D5                  of described in Reference using the fit described                                                                  finite Reference 6-15 match the expected trend from a best case finite element model for the NOP and SLB conditions for the Model F SGs and NOP conditions for the       the Model D5 SG.
-the model was initialized by simulating the tube expansion process. The expansion process was conservatively simulated by applying a low value of expansion pressure [ ]8.c.e inside the tube, resulting in initial tube to tubesheet contact, and then removing the tube expansion internal pressure.
Model 05 To further address the concern                  pressure may be lost at displacements concern that contact pressure                 displacements ranging between 1E-3 in and 1E-4 in, between                    in, the "Unit Cell" model is extensively              Section 1.3 of this extensively discussed in Section        this above..
The calculated dilation of the tubesheet bore due to the simulation of the tube expansion is [ ] 8,C,e inch for all models of SG considered.
response above 30 30
As discussed in Section 6.2.5 of the H* WCAP reports, the operating pressure loads, were applied to the initialized model in a sequential manner, and the resulting contact pressures were calculated when a range of displacements (termed OlE-bar")
were applied as boundary conditions to the model. Figure RA14-2 shows the updated sequential loading (includes application of thermal loads) of the model and relates it to the steps discussed in Section 6.2.5 and Tables 6-18 and 6-19 of the H* WCAPs. The OlE-bar" values shown as the displacement inputs on Tables 6-18 and 6-19 in the H* WCAP reports are uni-directional displacements (in inches) that are NOT the same as eccentricity and also not the same as (Eccentricity is defined as the difference between the maximum and minimum diameters of a bore divided by the nominal diameter of the bore. The units of eccentricity are inch/inch.)
The displacement inputs applied to the unit cell model are assumed values that based on prior analyses that envelope the expected tubesheet displacement for all of the applicable operating conditions.
It is important to note that the unit cell model as described in Section 6.2.5 of the H* WCAP reports utilizes boundary conditions chosen to minimize the tube-to-tubesheet contact pressures for the applied relative displacements.
To interpret the results from the unit cell model properly, the following must be observed:
* To address if tube to tubesheet contact continues for all the assumed tubesheet displacements, the appropriate reference condition is the initialized condition (after Step 4) of the model that simulates a tube expanded in the tubesheet bore. 19 LTR-SGMP-09-109 NP-Attachment To compare the results of the unit cell model with the 3D FEA model, the appropriate reference condition of the unit cell model is the initial model (Step 0) without the tube expansion simulated and thermal loads must be included.Figures RAI4-3 and RAI4-4 show the average tubesheet bore dilation (AD) as a function of tubesheet relative displacement (E-bar) for the Model F and Model D5. The average tube bore dilation at zero E-bar input is the result of the temperature and pressure loading of the unit cell model. Initially, application of the displacement input "E-bar" results in more significant hole dilation, but rapidly takes on a shallower slope as the applied displacement increases.
The curves are characteristically the same for the Model F and Model D5 steam generators and also for the different operating conditions, NOP and SLB, for the different models of SGs.Similarly, Figures RAI4-5 and RAI4-6 show the tubesheet bore eccentricity "e" as a function of tubesheet relative displacement (E-bar) for the Model F and Model D5. Eccentricity initially increases with application of the displacement boundary condition (E-bar) simulating the load due to pressure differential across the tubesheet, but the rate of increase decays with increasing E-bar. A significant difference is noted between NOP and SLB conditions at large values of E-bar. This difference reflects the fact that the uniform growth of the tube bore hole due to increased temperature overwhelms the effect of application of the displacement boundary condition (E-bar) on tubesheet bore eccentricity.
During the SLB event, the temperature is decreased and the differences in DMAX and DMIN remain more significant as the displacement boundary condition is increased, although the rate of increase in the difference between DMAX and DMIN is reduced at some point.. Eventually, at NOP conditions, the difference between DMAX and DMIN tends to become decrease even though a greater displacement (E-bar) is applied, leading to a reduction of eccentricity "e." Figures RAI4-7 and RAI4-8 show the contact pressure as a function of tubesheet relative displacement (E-bar) for the Model F and Model D5 for both NOP and SLB conditions based on the unit cell model. As expected, both NOP and SLB contact pressure decrease with increasing displacement inputs, ultimately going to zero at a very large value of applied displacements.
It is to be noted that the maximum displacement assumed is significantly greater than would be predicted by the 3D FEA model. Over the entire range of assumed displacement conditions, the SLB contact pressure exceeds that for NOP conditions.
Table RAI4-5 summarizes the eccentricity, AD and predicted contact pressure using the unit cell model for various values of applied displacement (E-bar) for both the model F and Model D5 SGs. The true eccentricity
([Dmax-Dmin]/Dnom) is shown for the applied displacement, E-bar.Table RAI4-5 also provides a comparison of the AD predicted by the unit cell model for the two reference conditions noted above, that is, for the total AD from the model without the simulated tube expansion (reference step 0 in Table 6-18) and for the initialized case with the tube expansion simulated (reference step 4 in Table 6-18).20 LTR-SGMP-09-109 NP-Attachment
* To compare the results of the unit cell model with the 3D FEA model, the appropriate reference condition of the unit cell model is the initial model (Step 0) without the tube expansion simulated and thermal loads must be included.
Figures RA14-3 and RA14-4 show the average tubesheet bore dilation (L10) as a function of tubesheet relative displacement (E-bar) for the Model F and Model 05. The average tube bore dilation at zero E-bar input is the result of the temperature and pressure loading of the unit cell model. Initially, application of the displacement input "E-bar" results in more significant hole dilation, but rapidly takes on a shallower slope as the applied displacement increases.
The curves are characteristically the same for the Model F and Model 05 steam generators and also for the different operating conditions, NOP and SLB, for the different models of SGs. Similarly, Figures RA14-5 and RA14-6 show the tubesheet bore eccentricity "e" as a function of tubesheet relative displacement (E-bar) for the Model F and Model 05. Eccentricity initially increases with application of the displacement boundary condition (E-bar) simulating the load due to pressure differential across the tubesheet, but the rate of increase decays with increasing E-bar. A significant difference is noted between NOP and SLB conditions at large values of E-bar. This difference reflects the fact that the uniform growth of the tube bore hole due to increased temperature overwhelms the effect of application of the displacement boundary condition (E-bar) on tubesheet bore eccentricity.
During the SLB event, the temperature is decreased and the differences in OMAX and OMIN remain more significant as the displacement boundary condition is increased, although the rate of increase in the difference between OMAX and OM IN is reduced at some point. . Eventually, at NOP conditions, the difference between OMAX and OMIN tends to become decrease even though a greater displacement (E-bar) is applied, leading to a reduction of eccentricity "e." Figures RA14-7 and RA14-8 show the contact pressure as a function of tubesheet relative displacement (E-bar) for the Model F and Model 05 for both NOP and SLB conditions based on the unit cell model. As expected, both NOP and SLB contact pressure decrease with increasing displacement inputs, ultimately going to zero at a very large value of applied displacements.
It is to be noted that the maximum displacement assumed is significantly greater than would be predicted by the 3D FEA model. Over the entire range of assumed displacement conditions, the SLB contact pressure exceeds that for NOP conditions.
Table RA14-5 summarizes the eccentricity, L10 and predicted contact pressure using the unit cell model for various values of applied displacement (E-bar) for both the model F and Model 05 SGs. The true eccentricity
([Omax-Omin]/Onom) is shown for the applied displacement, E-bar. Table RA14-5 also provides a comparison of the L10 predicted by the unit cell model for the two reference conditions noted above, that is, for the total L10 from the model without the simulated tube expansion (reference step 0 in Table 6-18) and for the initialized case with the tube expansion simulated (reference step 4 in Table 6-18). 20 LTR-SGMP-09-1 09 NP-AttachmentFurther, Table RAI4-5 provides a summary of contact pressures between the tube and the tubesheet for various applied values of E-bar for the Model F and Model D5 SGs. The "Modified Contact Pressure" is the "Raw Contact Pressure" from the unit cell model adjusted for the actual tube expansion process ([ ]a,c,e psi compared to the simulation at [ I a,c,e psi) real Model F and Model D5 geometry and more realistic operating conditions of pressures and temperatures.
For all cases of applied displacement, positive contact pressure remains between the tube and tubesheet.
It should be noted that the largest value of applied displacement (E-bar) is well in excess of the displacement predicted by the 3D FEA model.Table RAI4-6 provides similar data to that in Table RAI4-5, except that the data is based on the 3D FEA model.Comparison of Tables RAI4-5 and RAI4-6 leads to the following observations:
1.The ADs from the 3D FEA model are significantly less than the corresponding ADs from the unit cell model from the unloaded to the fully loaded condition (i.e., from step 0 to step 9) for both NOP and SLB conditions.
This leads to the conclusion that the unit cell model displacement results and contact pressure predictions conservatively represent the reference 3D FEA model results.2. The eccentricities from the unit cell model are generally comparable to those from the 3D FEA model. A more exact comparison is difficult based on the available data; however, it isclear that the actual range of eccentricities from the 3D FEA model was adequately addressed by the unit cell model.3. The method of Reference 6-15 of the H* WCAP report for adjusting contact pressure provides acceptable results for all conditions except the SLB condition for the Model D5 SGs The method of Reference 6-15 significantly under-predicts contact pressure for the Model D5 SLB conditions.
Referring to Figure RAI4-6, the method for calculating the reduction in contact pressure defined by the White Paper, when adjusted for temperature effects, shows that SLB contact pressure is increased relative to normal operating conditions.
21 L TR-SGMP-09-1 09 NP-Attachment Further, Table RA14-5 provides a summary of contact pressures between the tube and the tubesheet for various applied values of E-bar for the Model F and Model 05 SGs. The "Modified Contact Pressure" is the "Raw Contact Pressure" from the unit cell model adjusted for the actual tube expansion process ([ ]a,c,e psi compared to the simulation at [ ] a,c,e psi) real Model F and Model 05 geometry and more realistic operating conditions of pressures and temperatures.
For all cases of applied displacement, positive contact pressure remains between the tube and tubesheet.
It should be noted that the largest value of applied displacement bar) is well in excess of the displacement predicted by the 30 FEA model. Table RA14-6 provides similar data to that in Table RAI4-5, except that the data is based on the 30 FEA model. Comparison of Tables RA14-5 and RA14-6 leads to the following observations:
1.The from the 30 FEA model are significantly less than the corresponding from the unit cell model from the unloaded to the fully loaded condition (Le., from step 0 to step 9) for both NOP and SLB conditions.
This leads to the conclusion that the unit cell model displacement results and contact pressure predictions conservatively represent the reference 30 FEA model results. 2. The eccentricities from the unit cell model are generally comparable to those from the 30 FEA model. A more exact comparison is difficult based on the available data; however, it is clear that the actual range of eccentricities from the 30 FEA model was adequately addressed by the unit cell model. 3. The method of Reference 6-15 of the H* WCAP report for adjusting contact pressure provides acceptable results for all conditions except the SLB condition for the Model 05 SGs The method of Reference 6-15 significantly under-predicts contact pressure for the Model 05 SLB conditions.
Referring to Figure RAI4-6, the method for calculating the reduction in contact pressure defined by the White Paper, when adjusted for temperature effects, shows that SLB contact pressure is increased relative to normal operating conditions.
21 LTR-SGMP-09-109 NP-Attachment Table RAI4-5 Eccentricity, Contact Pressure and AD Results from Unit Cell Model Square Cell Results Square Cell Results Square Cell Results Square Cell -Average Delta D rinit v Raw Contact Modified Contact Preslure(1)N[2) -cl(3)Ecrenricit Sn 1 5tep 0(2) -Stp9' Step 4 (4) -Sten 903)SG "E bar" NOP SLB NOP SLB NOP SLB NOP SLB NOP SLB Model in in/in in/in si psi psi psi in in in in F F F F D5_D5_D5 D5 1. Accounts for expansion pressure and geometry.
: 2. See Section 6.2.5 H* WCAP. Step 0 is the condition of the unit-cell model prior to any modifications for tube expansion, loading, etc.3. See Section 6.2.5 H* WCAP. Step 9 is the condition of the unit cell model after all loading conditions have been applied.4. See Section 6.2.5 H* WCAP. Step 4 is the initialized condition of the Unit Cell model after tube expansion has been simulated.
a,c,e 22 L TR-SGMP-09-1 09 NP-Altachment Table RA14-5 Eccentricity, Contact Pressure and Results from Unit Cell Model Square Cell Results Square Cell Results Square Cell Results Square Cell -Average Delta D Raw Contact Modified Contact Eccentricity Pressure(1)
Pressure(1)
Step 0(2) -Step 9(3) Step 4(4) -Step 9(3) SG "E bar" NOP SLB NOP SLB NOP SLB NOP SLB NOP SLB Model a,c,e -in in/in in/in psi psi psi psi in in in in F F F F D5 D5 D5 D5 Notes: 1. Accounts for expansion pressure and geometry.
: 2. See Section 6.2.5 H' WCAP. Step 0 is the condition of the unit-cell model prior to any modifications for tube expansion, loading, etc. 3. See Section 6.2.5 H' WCAP. Step 9 is the condition of the unit cell model after all loading conditions have been applied. 4. See Section 6.2.5 H' WCAP. Step 4 is the initialized condition of the Unit Cell model after tube expansion has been simulated.
22 LTR-SGMP-09-109 NP-Attachment Table RAI4-6 Eccentricity, Bore Dilation and Contact Pressure from 3D FEA Model II Hstar Analysis Hstar Analysis Hstar Analysis -Avg. A D Ec.ce.ntricitvAva Cnntne.t Nn I had tn _OP SLB NOP tPs No SLB SG Model and Contact Pressure NOP SLB NOP SLB NOP SLB Reduction Model in/in in/in psi psi in in F -Ref. 6-15 Limiting Radius -F -Ref. 6-15D5 -Ref. 6-15D5 -White Paper Limiting Radius -D5 -Ref. 6-15 Limiting Radius -D5 -White Paper I F -Updated Model (1)D5 -Updated Model (1)a,c,e (1): Updated MOdel Iesults based on etimates trom approximate values in finite element analysis and do not reflect the result of a regression analysis.23 L TR-SGMP-09-1 09 NP-Atlachment Table RA14*6 Eccentricity, Bore Dilation and Contact Pressure from 3D FEA Model Hstar Analysis Hstar Analysis Hstar Analysis -AVQ. l!. 0 Eccentricity Avg. Contact Pressure No Load to OperatinQ SG Model and Contact Pressure NOP SLB NOP SLB NOP SLB a,C,e Reduction Model ,-inlin in/in psi psi in in -F -Ref. 6-15 Limiting Radius -F -Ref. 6-15 05 -Ref. 6-15 05 -White Paper Limiting Radius Ref. 6-15 Limiting Radius White Paper F -Updated Model (1) 05 -Updated Model (1) (1): Updated Model Results based on eSIimates from approximate values in finite element anal sis and do not reflect the result y of a regression analysis.
23 LTR-SGMP-09-109 NP-Attachment Figure RAI4-2 Unit Cell Model and Loading Sequence (1)(2)(3)Loading Steps: 0. Initial Model 1. Initial Tube to TS gap 2. Pressurize tube to 16ksi 3. Pressurize tube to 28ksi 4. Release Pressure on Tube 5. Apply ATV 1)6. Apply "E-bar" 7. Apply AP=[ ]apcse i 8. Apply AP=[ ]a.... psi 9. Apply AP=[ ]ace psi Notes: (1) The application of the unit cell model in support of Tables 6-18 and 6-19 does not include application of AT.Step 0 AP = 0 AT = 0 Unexpanded Tube e=0 e bar = 0 Step 5 Ap= 0 AT= 0 Expanded Tube e=0 ebar=0 Step 6-9 AP> 0 AT>0 Expanded Tube e> 0 ebar>0 24 (1 ) Step 0 boP = 0 boT = 0 Unexpanded Tube e=O e bar = 0 Figure RA14-2 Unit Cell Model and loading Sequence (2) Step 5 boP = 0 6.T= 0 Expanded Tube e=O e bar = 0 (3) Step 6-9 boP> 0 6.T> 0 Expanded Tube e>O e bar > 0 L TR-SGMP-09-109 NP-Attachment Loading Steps: O. Initial Model 1. Initial Tube to TS gap 2. Pressurize tube to 16ksi 3. Pressurize tube to 28ksi 4. Release Pressure on Tube 5. Apply ,n(l) 6. Apply "E-bar" 7. Apply
: 8. Apply
: 9. Apply la.c .* psi la.c .* psi la.c .* psi Notes: (1) The application of the unit cell model in support of Tables 6-18 and 6-19 does not include application oft.T. 24 LTR-SGMP-09-109 NP-Attachment a,c,e Figure RAI4-3 Relationship between "E-bar" and AD; Model F a,c,e Figure RAI4-4 Relationship between "E-bar" and AD; Model D5 25 L TR-SGMP-09-1 09 NP-Attachment a,c,e Figure RA14-3 Relationship between "E-bar" and AD; Model F a,c,e Figure RA14-4 Relationship between "E-bar" and AD; Model 05 25 LTR-SGMP-09-109 NP-Attachment a,c,e Figure RAI4-5 Relationship between "E-bar" and Eccentricity "e"; Model F a,c,e Figure RAI4-6 Relationship between "E-bar" and Eccentricity "e"; Model D5 26 L TR-SGMP-09-1 09 NP-Attachment a,c,e Figure RA14-5 Relationship between liE-bar" and Eccentricity "e"; Model F a,c,e Figure RA14-6 Relationship between liE-bar" and Eccentricity "e"; Model 05 26 LTR-SGMP-09-109 NP-Attachment a,c,e Figure RAI4-7 Relationship between "E-bar" and Contact Pressure; Model F a,c,e Figure RAI4-8 Relationship between "E-bar" and Contact Pressure; Model D5 27 L TR-SGMP-09-1 09 NP-Attachment a,c,e Figure RA14-7 Relationship between liE-bar" and Contact Pressure; Model F a,c,e Figure RA14-8 Relationship between liE-bar" and Contact Pressure; Model 05 27 LTR-SGMP-09-109 NP-Attachment


===2.0 Comparison===
LTR-SGMP-09-109 LTR-SGMP-09-109 NP-Attachment NP-Attachment a.c,e a,c,e Figure RAI 4-9
of Slice Model and Unit Cell Model Results The basis for applying the correlation for scale factor outside an "eccentricity" range of between 1E-3 to IE-4 inch in the calculation of contact pressure needs to be further explained.
                                  -   a,c,e a,c,e Figure RAI Figure    4-10 RAI 4-10 31 31
Values for displacements included in Table 6-18 (of WCAP-17071) suggest that contact pressure may be lost at displacement ranging between 1E-3 in to 1E-4 in.Response: Interpretation of the displacements noted in Table 6-18 of the WCAP reports was clarified in the prior response, Section 1.3. The values noted in the column titled "Displacement Total" refer to the condition of the unit cell model after Step 4 of the loading sequence (See Figure RAI4-2).When the true reference condition (Step 0) for total displacement is considered, the values of total displacement are significantly larger as noted previously.
Westinghouse agrees that the derivation of the fit in Reference 6-15 is non-intuitive and limited in its application.
However, the results of applying the fit described in reference 6-15 are acceptable relative to a best case finite element model (unit cell with thermal and AP loading) for the reasons described below.Westinghouse also agrees that the fit that describes the reduction in contact pressure for the steam line break condition in the Model D5 White Paper does not account for the reduction in contact pressure due to tube bore dilation in the same manner as the fit described in Reference 6-15. The results of using the fit described in Reference 6-15 also match the expected trend from a best case finite element model. See the response to b.4 below for more details.A series of tubesheet tube bore eccentricities were applied to the tubesheet cell model and combined with different pressure and temperature loads. The average, maximum and minimum values of the tube-to-tubesheet (TITS) contact pressures around the circumference of the tubewere reported.
The values of tubesheet relative displacement, pressure and temperature that were used in the analysis are summarized in the table below.Input Conditions for Unit Cell Model (no correlation implied)Internal Temperature Pressure Difference in AP, psi AT,OF ace 0.00 2.0E-04 4.OE-04 28 LTR-SGMP-09-109 NP-Attachment


===2.0 Comparison===
LTR-SGMP-09-109 LTR-SGMP-09-1 09 NP-Attachment NP-Attachment Calculation Basis for Contact Pressure 2.1 Calculation                      Pressure Reduction Reduction Factors Factors II Provide Provide the calculation calculationbasis basis for the upper upper and and lower lower curves provided provided in in Figure Figure RA14-2 RAI 4-2    I


of Slice Model and Unit Cell Model Results The basis for applying the correlation for scale factor outside an "eccentricity" range of between 1 E-3 to 1 E-4 inch in the calculation of contact pressure needs to be further explained.
===Response===
Values for displacements included in Table 6-18 (of WCAP-17071) suggest that contact pressure may be lost at displacement ranging between 1 E-3 in to 1 E-4 in. Response:
The original figure RAI4-2, referred to in the question, is reproduced reproduced here as RAI4-10 RA14-10 to provide provide the foundation for the question and the response. Note that the scale of the y-axis has been corrected corrected as discussed in the meeting on August 17, 2009.
Interpretation of the displacements noted in Table 6-18 of the WeAP reports was clarified in the prior response, Section 1.3. The values noted in the column titled "Displacement Total" refer to the condition of the unit cell model after Step 4 <;>f the loading sequence (See Figure RAI4-2). When the true reference condition (Step 0) for total displacement is considered, the values of total displacement are significantly larger as noted previously.
a,c,e Figure RA14-10 RAI4-10 (original Figure RAI4-2)
Westinghouse agrees that the derivation of the fit in Reference 6-15 is non-intuitive and limited in its application.
The upper upper curve in the figure above is based based on the data from the following table:
However, the results of applying the fit described in reference 6-15 are acceptable relative to a best case finite element model (unit cell with thermal and loading) for the reasons described below. Westinghouse also agrees that the fit that describes the reduction in contact pressure for the steam line break condition in the Model 05 White Paper does not account for the reduction in contact pressure due to tube bore dilation in the same manner as the fit described in Reference 6-15. The results of using the fit described in Reference 6-15 also match the expected trend from a best case finite element model. See the response to b.4 below for more details. A series of tubesheet tube bore eccentricities were applied to the tubesheet cell model and combined with different pressure and temperature loads. The average, maximum and minimum values of the tube-to-tubesheet (TITS) contact pressures around the circumference of the tube were reported.
32 32
The values of tubesheet relative displacement, pressure and temperature that were used in the analysis are summarized in the table below. Input Conditions for Unit Cell Model (no correlation implied) Internal Temperature e Pressure Difference in psi OF a,c,e 0.00 -2.0E-04 4.0E-04 --28 LTR-SGMP-09-109 NP-Attachment Normal operating (NOP) conditions in the Model D5 and Model F steam generators are represented by a AP of [ ]a,c,e psi and a AT of [ ] a,c,e OF. Main steam line break (SLB)conditions in the Model D5 are represented by a AP of [ ] " psi and a AT of [ ] a,c,e OF.The value of AP in the tubesheet cell can change as a function of elevation in the tubesheet due to the distribution of crevice pressure.
The results of the study include the data for a depth ratio of 0.9 which is an elevation roughly 2 inches below the top of the tubesheet.
The values of AP represented in this study account for the region of interest near the top of the tubesheet where the maximum eccentricity in the tubesheet is expected and where the crevice fluid is transitioning from the crevice conditions to the secondary side fluid conditions. The region roughly 2 inches below the top of the tubesheet is also where a significant portion of the T/TS contact pressure develops so it is a good indicator of trends in the effect that different operating conditions have on the contact pressure.The original results in section 6.2.5 of WCAP-1 7071-P were used to verify that the reduction in T/TS contact pressure as a function of tubesheet tube bore eccentricity was appropriate for the Model F SG. The original relationship that is used to define the reduction in T/TS contact pressure as'a function of eccentricity is described in section 6.3 of WCAP 17071-P and WCAP 17072-P. However, the result of applying the fit described in section 6.3 to the Model D5 SG during SLB was shown to be inconsistent with the expected trend from the more detailedanalysis described in section 6.2.5. The results of section 6.2.5 were then used to define a new relationship between the reduction in T/TS contact pressure and tube bore eccentricity.
This new relationship is described in the Model D5 White Paper (Reference 12). Figure RAI4-8 shows the result of applying the new relationship to the Model D5 SLB conditions (i.e., White Paper results, Reference
: 12) in comparison with the results from the old 3 rd order polynomial relationship.
Because the tubesheet temperature induced hole dilation, potentially the most significant factor in contact pressure reduction, was not considered in the Model D5 condition results, a third curve was added to the figure titled "Model D5 FEA trend." This curve represents the most accurate calculation of the contact pressure ratio.Figure RAI4-9 shows the contact pressure ratio (PCSLB/PCNoP) as a function of tubesheet relative displacement, E-bar. It is clear from Figure RAI4-9 that the results of using the old fit for the Model D5 SLB are inconsistent with the more detailed analysis.
At SLB conditions, the tubesheet bore dilation is relatively larger than at NOP conditions due to the increased bending of the TS and decreased thermal expansion.
Therefore, it is expected that the T/TS contact pressure ratio should increase by a factor of at least [ ]a,c,e (see Figure RAI4-9) when going from NOP to SLB. It is also expected that the tube to tubesheet contact pressure should decrease with increasing tube bore eccentricity. The H* results using the old fit for the Model D5clearly do not follow either expectation from the detailed analysis.
However, when the new fit results are applied to the H* calculation process the relationship between TITS contact pressure in the Model D5 is much more reasonable and follows the expected trend from the more detailed analysis.The Model F H* contact pressure results, using the old fit, are well within the range predicted by the more detailed analysis in section 6.2.5 and the additional work described in this RAI response.
See Figure RAI 4-10 below. This means that the old fit is appropriate to use for the 29\ L TR-SGMP-09-109 NP-Attachment Normal operating (Nap) conditions in the Model 05 and Model F steam generators are represented by a AP of [ ]a,c,e psi and a AT of [ ] a,c,e of. Main steam line break (SLB) . conditions in the Model 05 are represented by a AP of [ ] a,c,e psi and a AT of [ ] a,c,e of. The value of AP in the tubesheet cell can change as a function of elevation in the tubesheet due to the distribution of crevice pressure.
The results of the study include the data for a depth ratio of 0.9 which is an elevation roughly 2 inches below the top of the tubesheet.
The values of AP represented in this study account for the region of interest near the top of the tubesheet where the maximum eccentricity in the tubesheet is expected and where the crevice fluid is transitioning from the crevice conditions to the secondary side fluid conditions.
The region roughly 2 inches below the top of the tubesheet is also where a significant portion of the TITS contact pressure develops so it is a good indicator of trends in the effect that different operating conditions have on the contact pressure.
The original results in section 6.2.5 of WCAP-17071-P were used to verify that the reduction in TITS contact pressure as a function of tubesheet tube bore eccentricity was appropriate for the Model F SG. The original relationship that is used to define the reduction in TITS contact pressure as'a function of eccentricity is described in section 6.3 of WCAP 17071-P and WCAP 17072-P. However, the result of applying the fit described in section 6.3 to the Model 05 SG during SLB was shown to be inconsistent with the expected trend from the more detailed analysis described in section 6.2.5. The results of section 6.2.5 were then used to define a new relationship between the reduction in TITS contact pressure and tube bore eccentricity.
This new relationship is described in the Model 05 White Paper (Reference 12). Figure RA14-8 shows the result of applying the new relationship to the Model 05 SLB conditions (i.e., White Paper results, Reference
: 12) in comparison with the results from the old 3 rd order polynomial relationship.
Because the tubesheet temperature induced hole dilation, potentially the most significant factor in contact pressure reduction, was not considered in the Model 05 condition results, a third curve was added to the figure titled "Model 05 FEA trend." This curve represents the most accurate calculation of the contact pressure ratio. Figure RA14-9 shows the contact pressure ratio (PCsLB/PCNoP) as a function of tubesheet relative displacement, E-bar. It is clear from Figure RA14-9 that the results of using the old fit for the Model 05 SLB are inconsistent with the more detailed analysis.
At SLB conditions, the tubesheet bore dilation is relatively larger than at Nap conditions due to the increased bending of the TS and decreased thermal expansion.
Therefore, it is expected that the TITS contact pressure ratio should increase by a factor of at least [ ]a,c,e (see Figure RAI4-9) when going from Nap to SLB. It is also expected that the tube to tubesheet contact pressure should decrease with increasing tube bore eccentricity.
The H* results using the old fit for the Model 05 clearly do not follow either expectation from the detailed analysis.
However, when the new fit results are applied to the H* calculation process the relationship between TITS contact pressure in the Model 05 is much more reasonable and follows the expected trend from the more detailed analysis.
The Model F H* contact pressure results, using the old fit, are well within the range predicted by the more detailed analysis in section 6.2.5 and the additional work described in this RAI response.
See Figure RA14-10 below. This means that the old fit is appropriate to use for the 29 LTR-SGMP-09-109 NP-Attachment Model F NOP and SLB conditions and the NOP condition in the Model D5 SG. The results of using the fit described in Reference 6-15 match the expected trend from a best case finite element model for the NOP and SLB conditions for the Model F SGs and NOP conditions for the Model D5 SG.To further address the concern that contact pressure may be lost at displacements ranging between 1 E-3 in and 1 E-4 in, the "Unit Cell" model is extensively discussed in Section 1.3 of this response above.30. " L TR-SGMP-09-1 09 NP-Attachment Model F NOP and SLB conditions and the NOP condition in the Model 05 SG. The results of using the fit described in Reference 6-15 match the expected trend from a best case finite element model for the NOP and SLB conditions for the Model F SGs and NOP conditions for the Model 05 SG. To further address the concern that contact pressure may be lost at displacements ranging between 1 E-3 in and 1 E-4 in, the "Unit Cell" model is extensively discussed in Section 1.3 of this response above . 30 LTR-SGMP-09-109 NP-Attachment a.c,e Figure RAI 4-9-a,c,e Figure RAI 4-10 31 LTR-SGMP-09-109 NP-Attachment a,c,e Figure RAI 4-9 a,c,e Figure RAI 4-10 31 LTR-SGMP-09-109 NP-Attachment


===2.1 Calculation===
LLTR-SGMP-09-109        NP-Attachment TR-SGMP-09-1 09 NP-Attachment Eccentricity (ADmax-Eccentricity        (L1Dmax-              Reduction in Contact                  Normalization Normalization            Contact Pressure ADmin) (in)
L1Dmin)        (in)                    Pressure (psi)(1)
Pressure      (psi)(1)                  Basis                    Reduction Reduction (psi)
(psi)                  Factor(psi/psi) 0                                    0                                                            0 2E-4                            [    )) a,c,e aT,c,e  psi                    1200 1200                      [    ] a,c,e a,c,e
                                                        ] a,c,e psi                                                        a,c,e 4E-4 5E-4 r[ ]a~ce psi                                                      1[  Ja,c,e
                                                                                                                          ]a,c,e 5E-4                            r ] a,c,e      psi                                                    ] a,c,e 6E-4                                      ] a,c,e I a,c,e I
Notes: (1) 6E-4                              [                                                            1[    Ja,c,e a,c,e:
(1) Contact Contact stress reductions reductions are based on the values on Table RAI4-3    RA14-3 Referring to Table RAI 4-3, the contact pressure for a round tube bore hole is calculated to be Referring to Table RAI 4-3, the contact pressure for a round tube bore hole is calculated to be I
[
I a,c,e psi (Ratio = 1.0). The contact pressure for a tube bore hole that results in a
              ] a,c,e psi (Ratio = 1.0). The contact pressure for a tube bore hole that results in a contact pressure pressure ratio reduction of ((                        ]a,c,e (Ratio =
t,c,e          = [      ]a,c,e), which corresponds to an
                                                                                                ]8,ce),
eccentricity of 2E-4 inch, eccentricity                    inch, is [            ]a,c,e psi. The absolute reduction
                                                        ]a,c,e                                reduction in  in contact pressure is        is I[      )) a,c,e psi.
psi.
The total reduction in contact pressure        pressure using the new model is approximately [                            a,c,e psi (see
                                                                                                                          ] a,c,e Figure Figure 6-69 of WCAP-17072-P).
WCAP-17072-P).                 To plot the absolute reduction in                in contact pressure of I        I] a,c,e  psi for an eccentricity of 2E-4 on Figure RAI4-1 0, the value is normalized by the total a,c,e psi for an eccentricity of 2E-4 on Figure RAI4-10, the value is normalized by the total reduction reduction in contact pressure  pressure of [            )) a,c,e a,c,e psi from the new method. This value represents a reduction reduction in    in contact pressure of [              ]a,c,e.
                                                        ]a,c,e.
Again, referring to Table RAI 4-3, the contact pressure for a round tube hole is calculated to be Again, referring to Table RAI 4-3, the contact pressure for a round tube hole is calculated to be I          I a,c,e psi. The contact pressure for a tube bore hole that results in a contact pressure
[          ] a,c,e psi. The contact pressure for a tube bore hole that results in a contact pressure ratio reduction reduction of ((                ]a,c,e (Ratio = ((
                                        ]a,c,e                          ] a,c,e),
ace), which corresponds corresponds to be eccentricity eccentricity of 4E-4 inch, inch, is [              ] ac,e a,c,e psi. The absolute absolute reduction reduction in contact pressure is [              I] a,c,e psi.
Again, the total reduction in                  contact pressure in contact    pressure using    using the  new model the new  model is      approximately ((
is approximately                a,c,e I] a,c,e psi (see Figure 6-69 of WCAP-17072-P).WCAP-17072-P). To plot the absolute            absolute reduction in contact pressure of I[            I] a,c,e psi  for  an    eccentricity of 4E-4 on Figure RAI4-10, the value is normalized by the a,c,e psi for an eccentricity of 4E-4 on Figure RAI4-10, the value is normalized by the total reduction in contact pressure of ((                          ] a,c,,
a,c,e psi from the new method. This value represents    represents a reduction in contact pressure  pressure of ((            ] ac,e a,c,e.
The same calculation was completed          completed for an eccentricity of 6E-4 in. The value for 5E-4 in is an interpolated value between interpolated                between 4 E-4 in and 6E-4 in.
The bottom curve in the figure above is generated              generated using the 33rd    rd order polynomial polynomial fit. The results results are summarized in the following table:
33 33


Basis for Contact Pressure Reduction Factors I Provide the calculation basis for the upper and lower curves provided in Figure RAI 4-2 I Response: The original figure RAI4-2, referred to in the question, is reproduced here as RAI4-10 to provide the foundation for the question and the response.
L TR-SGMP-09-1 09 NP-Attachment LTR-SGMP-09-109        NP-Attachment eccentricity (in)
Note that the scale of the y-axis has been corrected as discussed in the meeting on August 17, 2009.a,c,e Figure RAI4-10 (original Figure RAI4-2)The upper curve in the figure above is based on the data from the following table: 32 L TR-SGMP-09-1 09 NP-Attachment
E, eccentricity      (in)          TITS Contact Contact                  Normalized Normalized Contact Pressure Reduction Reduction            Pressure Pressure Reduction Reduction (psi) 6.36E-07                        [        ))a~ce a,c,e
[      lace
                                                                                                  ] a,c,e 5.53E-05                        J        ] a,c,e lace                  [    J]a~ce a,c,e 3.16E-04                                  ] a,c,e
                                                                    ]a~c~e                      ))a,c,e a,c,e
[                              [
5.69E-04                        [      .))a~c~e a,c,e                [    J]aa,c,e ce 9.07E-04                                  ] a,c,e
                                                                    ]a.c~e                      ))a.c.e a,c,e
[                              [
rd 2.2 Conservatism Conservatism of 3          3 rd Order Polynomial Polynomial Fit from WCAP            Reference 6-15 WCAP Reference      6-15 Provide Provide the basis model remains basis for why the I1D conservative.
remains conservative.
ho/e adjustment ADhole  adjustment for contact          pressure made contact pressure      made usingusing the old I


===2.1 Calculation===
===Response===
The key conclusions conclusions from the comparison of the Reference      Reference 6-15 analysis, the WCAP results and the results of the square cell tubesheet model          model are:
1.) The fit described 1.)                              Reference 6-15 of the H*
described in Reference                                                    conservative when applied H* WCAP reports is conservative                        applied to the NOP  Nap condition in both the Model D5              05 and Model Model F SG. The fit tends to under-estimate the contact pressure during Nap              NOP by  by as    much as as much    as ((          ]a,c,e psi
                                                                                                      ]a,c,e      to ((
psi to          Ia,c,e
                                                                                                                            ]a,c,s psi) for the Model F SG and as much as [ ]a,c,e                                          D5 SG ([([
                                                                        ]a,c,s % for the Model 05                    ]a,c,e psi to
                                                                                                                    ]a,c,s      to
[I              psi) (see Table RAI4-6).
              ]a,c,s psi)
              ]a,c,e                        RAI4-6).
2.) The fit described in Reference 2.)                              Reference 6-15 of the H*      H* WCAP reports is comparable comparable when applied    applied to the SLB condition in the Model F SG. The fit described              described in the Model D5      05 White PaperPaper tends to over-estimate the contact pressure, by as much as [ ]a,c,s                                  %, during SLB
                                                                                                    ]a,c,e %,
([
([      ]a,c,e psi to ((
                ]a,c,s                  ]a,c,e psi) because
                                        ]a,c,s      because the White Paper does not fully account        account for the  the change in tube bore diameter during the transient.
3.)
3.) The fit described            Reference 6-15 of the H*
described in Reference                          H* WCAP reports significantly under-estimates under-estimates contact pressure, by as much as (( ]a,c,s the contact                                                    ]aC.6 %,%, during the D505 SLB condition (from
[.
            ]a,c,e psi
            ]a,c,s to ((
psi to        ]a,c,e  psi).
                                    ]a,c,s psi).
4.) The square cell tubesheet finite element        element model model shows an increase increase in contact contact pressure when going from Nap        NOP to SLB conditions in      in both the 05  D5 and F SGs.
34


Basis for Contact Pressure Reduction Factors I Provide the calculation basis for the upper and lower curves provided in Figure RA14-2 Response:
LTR-SGMP-09-109     NP-Attachment LTR-SGMP-09-1 09 NP-Attachment 5.) Using the results from the square cell model to estimate the magnitude of the contact pressure reduction reduction from the change in  in tube bore diameter diameter calculated using the 3D 30 finite finite element results from the lower lower SG tubesheet complex complex model show that the contact pressure pressure still increases increases when going from NOP to SLB conditions conditions inin both the Model F andand Model D5 SG.
The original figure RAI4-2, referred to in the question, is reproduced here as RA14-10 to provide the foundation for the question and the response.
Model 05 The results of this analysis show that NOP contact pressures pressures that define     H* in the Model F and define H*
Note that the scale of the y-axis has been corrected as discussed in the meeting on August 17, 2009. a,c,e Figure RA14-10 (original Figure RAI4-2) The upper curve in the figure above is based on the data from the following table: 32 LTR-SGMP-09-109 NP-Attachment Eccentricity (ADmax- Reduction in Contact Normalization Contact Pressure ADmin) (in) Pressure (psi)(1) Basis Reduction (psi) Factor(psi/psi) 0 0 0 2E-4 ] aT,c,e psi 1200 a,c,e 4E-4 a,c,e psi a,c,e 5E-4 [ ]a~ce psi [ ]a,c,e 6E-4 I a,c,e [ a,c,e: Notes: (1) Contact stress reductions are based on the values on Table RAI4-3 Referring to Table RAI 4-3, the contact pressure for a round tube bore hole is calculated to be I I a,c,e psi (Ratio = 1.0). The contact pressure for a tube bore hole that results in a contact pressure ratio reduction of [ ]a,c,e (Ratio = [ ]8,ce), which corresponds to an eccentricity of 2E-4 inch, is [ ]a,c,e psi. The absolute reduction in contact pressure is I ] a,c,e psi.The total reduction in contact pressure using the new model is approximately a,c,e psi (see Figure 6-69 of WCAP-17072-P). To plot the absolute reduction in contact pressure ofI I a,c,e psi for an eccentricity of 2E-4 on Figure RAI4-1 0, the value is normalized by the total reduction in contact pressure of [ ] a,c,e psi from the new method.
Model D5 Model 05   SG are conservative conservative    and that a more   realistic model of contact   pressure pressure reduction reduction as a function of tube bore bore deformation deformation (including both dilation and eccentricity) eccentricity) would predict an increase in tube to tubesheet contact increase                          contact pressure at SLB conditions compared to NOP      NOP conditions.
This value represents a reduction in contact pressure of [ ]a,c,e.Again, referring to Table RAI 4-3, the contact pressure for a round tube hole is calculated to be I I a,c,e psi. The contact pressure for a tube bore hole that results in a contact pressure ratio reduction of [ ]a,c,e (Ratio = [ ] ace), which corresponds to be eccentricity of 4E-4 inch, is [ ] ac,e psi. The absolute reduction in contact pressure is [ I a,c,e psi.Again, the total reduction in contact pressure using the new model is approximately
(See also Section 2.3) 2.3 SLB vs. NOP NOP Contact Contact Pressures Pressures Provide Provide an appropriate appropriatebasisbasis for demonstrating demonstratingthat  thatjoints  tighten during jOints tighten   during a postulated postulated SLB  event.
[ I a,c,e psi (see Figure 6-69 of WCAP-17072-P).
SLB event. WhyWhy  is it acceptable acceptable  to compare compare    the contact  pressures    calculated contact pressures calculated using the original original  model   for NOP NOP to the contact contact pressures pressurescalculated calculatedusing using the new model for SLB  SLB for the Model D5 SGs?
To plot the absolute reduction in contact pressure ofI I a,c,e psi for an eccentricity of 4E-4 on Figure RAI4-10, the value is normalized by the total reduction in contact pressure of [ ] a,c,, psi from the new method. This value represents a reduction in contact pressure of [ ] ac,e The same calculation was completed for an eccentricity of 6E-4 in. The value for 5E-4 in is an interpolated value between 4 E-4 in and 6E-4 in.The bottom curve in the figure above is generated using the 3 rd order polynomial fit. The results are summarized in the following table: 33 L TR-SGMP-09-1 09 NP-Attachment Eccentricity (L1Dmax-Reduction in Contact Normalization Contact Pressure L1Dmin) (in) Pressure (psi)(1) Basis Reduction (psi) Factor(psi/psi) 0 0 0 2E-4 [ ] a,c,e psi 1200 [ ] a,c,e 4E-4 r ] a,c,e psi 1 Ja,c,e 5E-4 r ] a,c,e psi I ] a,c,e 6E-4 [ ] a,c,e 1 Ja,c,e Notes: (1) Contact stress reductions are based on the values on Table RA14-3 Referring to Table RAI 4-3, the contact pressure for a round tube bore hole is calculated to be [ ] a,c,e psi (Ratio = 1.0). The contact pressure for a tube bore hole that results in a contact pressure ratio reduction of [ t,c,e (Ratio = [ ]a,c,e), which corresponds to an eccentricity of 2E-4 inch, is [ ]a,c,e psi. The absolute reduction in contact pressure is [ ] a,c,e psi. The total reduction in contact pressure using the new model is approximately [ ] a,c,e psi (see Figure 6-69 of WCAP-17072-P).
To plot the absolute reduction in contact pressure of ] a,c,e psi for an eccentricity of 2E-4 on Figure RAI4-10, the value is normalized by the total reduction in contact pressure of [ ] a,c,e psi from the new method. This value represents a reduction in contact pressure of [ ]a,c,e. Again, referring to Table RAI 4-3, the contact pressure for a round tube hole is calculated to be [ ] a,c,e psi. The contact pressure for a tube bore hole that results in a contact pressure ratio reduction of [ ]a,c,e (Ratio = [ ] a,c,e), which corresponds to be eccentricity of 4E-4 inch, is [ ] a,c,e psi. The absolute reduction in contact pressure is [ ] a,c,e psi. Again, the total reduction in contact pressure using the new model is approximately [ ] a,c,e psi (see Figure 6-69 of WCAP-17072-P).
To plot the absolute reduction in contact pressure of [ ] a,c,e psi for an eccentricity of 4E-4 on Figure RAI4-10, the value is normalized by the total reduction in contact pressure of [ ] a,c,e psi from the new method. This value represents a reduction in contact pressure of [ ] a,c,e. The same calculation was completed for an eccentricity of 6E-4 in. The value for 5E-4 in is an interpolated value between 4 E-4 in and 6E-4 in. The bottom curve in the figure above is generated using the 3rd order polynomial fit. The results are summarized in the following table: 33 LTR-SGMP-09-109 NP-Attachment E, eccentricity (in) TITS Contact Normalized Contact Pressure Reduction Pressure Reduction (psi)6.36E-07 ]a~ce lace 5.53E-05 lace ]a~ce 3.16E-04 ]a~c~e ]a,c,e 5.69E-04 ]a~c~e ]a c e 9.07E-04 ]a.c~e ]a.c.e 2.2 Conservatism of 3 rd Order Polynomial Fit from WCAP Reference 6-15 Provide the basis for why the ADhole adjustment for contact pressure made using the old model remains conservative.
I Response: The key conclusions from the comparison of the Reference 6-15 analysis, the WCAP results and the results of the square cell tubesheet model are: 1.) The fit described in Reference 6-15 of the H* WCAP reports is conservative when applied to the NOP condition in both the Model D5 and Model F SG. The fit tends to under-estimate the contact pressure during NOP by as much as [ ]a,c,e psi to [ Ia,c,epsi) for the Model F SG and as much as [ ]a,c,e % for the Model D5 SG ([ ]a,c,e psi to I ]a,c,e psi) (see Table RAI4-6).2.) The fit described in Reference 6-15 of the H* WCAP reports is comparable when applied to the SLB condition in the Model F SG. The fit described in the Model D5 White Paper tends to over-estimate the contact pressure, by as much as [ ]a,c,e %, during SLB ([ ]a,c,e psi to [ ]a,c,e psi) because the White Paper does not fully account for the change in tube bore diameter during the transient.
3.) The fit described in Reference 6-15 of the H* WCAP reports significantly under-estimates the contact pressure, by as much as [ ]aC.6 %, during the D5 SLB condition (from]a,c,e psi to [ ]a,c,e psi).4.) The square cell tubesheet finite element model shows an increase in contact pressure when going from NOP to SLB conditions in both the D5 and F SGs.34 L TR-SGMP-09-1 09 NP-Attachment E, eccentricity (in) TITS Contact Normalized Contact Pressure Reduction Pressure Reduction (psi) 6.36E-07 [ ] a,c,e [ ] a,c,e 5.53E-05 J ] a,c,e [ J a,c,e 3.16E-04 [ ] a,c,e [ ] a,c,e 5.69E-04 [ .] a,c,e [ J a,c,e 9.07E-04 [ ] a,c,e [ ] a,c,e 2.2 Conservatism of 3 rd Order Polynomial Fit from WCAP Reference 6-15 Provide the basis for why the I1D ho/e adjustment for contact pressure made using the old model remains conservative.
Response:
The key conclusions from the comparison of the Reference 6-15 analysis, the WCAP results and the results of the square cell tubesheet model are: 1.) The fit described in Reference 6-15 of the H* WCAP reports is conservative when applied to the Nap condition in both the Model 05 and Model F SG. The fit tends to estimate the contact pressure during Nap by as much as [ ]a,c,e psi to [ ]a,c,s psi) for the Model F SG and as much as [ ]a,c,s % for the Model 05 SG ([ ]a,c,s psi to [ ]a,c,s psi) (see Table RAI4-6). 2.) The fit described in Reference 6-15 of the H* WCAP reports is comparable when applied to the SLB condition in the Model F SG. The fit described in the Model 05 White Paper tends to over-estimate the contact pressure, by as much as [ ]a,c,s %, during SLB ([ ]a,c,s psi to [ ]a,c,s psi) because the White Paper does not fully account for the change in tube bore diameter during the transient.
3.) The fit described in Reference 6-15 of the H* WCAP reports significantly under-estimates the contact pressure, by as much as [ ]a,c,s %, during the 05 SLB condition (from [. ]a,c,s psi to [ ]a,c,s psi). 4.) The square cell tubesheet finite element model shows an increase in contact pressure when going from Nap to SLB conditions in both the 05 and F SGs. 34 LTR-SGMP-09-109 NP-Attachment 5.) Using the results from the square cell model to estimate the magnitude of the contact pressure reduction from the change in tube bore diameter calculated using the 3D finite element results from the lower SG tubesheet complex model show that the contact pressure still increases when going from NOP to SLB conditions in both the Model F and Model D5 SG.The results of this analysis show that NOP contact pressures that define H*
in the Model F and Model D5 SG are conservative and that a more realistic model of contact pressure reduction as a function of tube bore deformation (including both dilation and eccentricity) would predict an increase in tube to tubesheet contact pressure at SLB conditions compared to NOP conditions.(See also Section 2.3)2.3 SLB vs. NOP Contact Pressures Provide an appropriate basis for demonstrating that joints tighten during a postulated SLB event. Why is it acceptable to compare the contact pressures calculated using the original model for NOP to the contact pressures calculated using the new model for SLBfor the Model D5 SGs?Response: Table RAI4-5 provides a summary of contact pressures between the tube and the tubesheet for various applied values of E-bar for the Model F and Model D5 SGs. Comparison of the eccentricity values calculated using the unit cell model (see Table RAI4-5) with the eccentricity values calculated from the 3D FEA model (see Table RAI4-1) shows that the eccentricities from both models are comparable.
It is not reasonable to expect exact matches of numbers between the two models, however, the order of magnitude of the calculated eccentricities is the same.Given that the two structural models provide similar eccentricities, the unit cell model shows that for these eccentricities, positive contact pressure exists between the tubes and the tubesheet for the entire range of displacements considered.
Further, the results show that the contact pressures at SLB conditions exceed those at NOP conditions (See Table RAI4-6). See also the discussion in Section 2.4 below.35 L TR-SGMP-09-1 09 NP-Attachment 5.) Using the results from the square cell model to estimate the magnitude of the contact pressure reduction from the change in tube bore diameter calculated using the 30 finite element results from the lower SG tubesheet complex model show that the contact pressure still increases when going from NOP to SLB conditions in both the Model F and Model 05 SG. The results of this analysis show that NOP contact pressures that define H* in the Model F and Model 05 SG are conservative and that a more realistic model of contact pressure reduction as a function of tube bore deformation (including both dilation and eccentricity) would predict an increase in tube to tubesheet contact pressure at SLB conditions compared to NOP conditions. (See also Section 2.3) 2.3 SLB vs. NOP Contact Pressures Provide an appropriate basis for demonstrating that jOints tighten during a postulated SLB event. Why is it acceptable to compare the contact pressures calculated using the original model for NOP to the contact pressures calculated using the new model for SLB for the Model D5 SGs? Response:
Table RA14-5 provides a summary of contact pressures between the tube and the tubesheet for various applied values of E-bar for the Model F and Model 05 SGs. Comparison of the eccentricity values calculated using the unit cell model (see Table RAI4-5) with the eccentricity values calculated from the 30 FEA model (see Table RAI4-1) shows that the eccentricities from both models are comparable.
It is not reasonable to expect exact matches of numbers between the two models, however, the order of magnitude of the calculated eccentricities is the same. Given that the two structural models provide similar eccentricities, the unit cell model shows that for these eccentricities, positive contact pressure exists between the tubes and the tubesheet for the entire range of displacements considered.
Further, the results show that the contact pressures at SLB conditions exceed those at NOP conditions (See Table RAI4-6). See also the discussion in Section 2.4 below. 35 LTR-SGMP-09-109 NP-Attachment


===2.4 Relative===
===Response===
Conservatism of "Old" and "New" Fit I lf both old and new models are conservative, is there an appropriate basis to show the relative conservatism of the methods?Response: As noted above in Section 1.3 of this response, tube bore dilation is a more significant factor in determining tube-to-tubesheet contact pressure at higher temperatures and the effect of eccentricity on contact pressure is reduced at higher temperatures.
RAI4-5 provides a summary of contact pressures Table RA14-5                                        pressures between the tube and the tubesheet for        for various applied values of E-bar for the Model FF and Model                D5 Model 05    SGs. Comparison    of   the the eccentricity values calculated using the unit cell model (see Table RAI4-5) with the eccentricity eccentricity                                                                                    eccentricity values values calculated from the 30  3D FEA model (see TableTable RAI4-1)
The methodology for addressing the effect of eccentricity on contact pressure discussed in Reference 6-15 and utilized in WCAP-17071-P, WCAP-17072-P, WCAP-17091-P and WCAP-17092-P reflects this fact and it, therefore, provides acceptably accurate contact pressure results at higher temperatures (i.e., for all conditions except the "colder" SLB condition).
RAI4-1) shows that the eccentricities eccentricities from from both models models are comparable. ItIt is not reasonable reasonable to expect exact matches                      between matches of numbers between the two models, however, the order of magnitude of the calculated eccentricities eccentricities is the same.
This includes NOP, SLB (higher temperature, > 400 0 F, and FLB, where appropriate).
structural models provide similar eccentricities, Given that the two structural                              eccentricities, the unit cell model model shows that for these eccentricities, eccentricities, positive positive contact pressure pressure exists between the tubes and the tubesheet for the entire range of displacements displacements considered. Further, the results show that the contact pressures at SLB conditions exceed those at NOP conditions (See Table RAI4-6). See also the              the discussion in Section Section 2.4 below.
Also, as noted in Section 1.3 of this report, the effect of eccentricity on contact pressure loss is a more significant factor at the lower SLB temperatures for the Model D5 SG, but tube bore dilation due to temperature and pressure needs to be considered (which was not addressed in the "new" method, a.k.a the White Paper method discussed in WCAP-17072-P or 17091-P).Moreover, the original 3rd order polynomial fit significantly over-predicts contact pressure loss during the "colder" Model D5 SLB transient (and Model 44F two loop plant SLB).Therefore, a more detailed model for contact pressure during a postulated SLB was developed.
35 35
Referring to Table RAI4-6, it shows that contact pressure increases during a SLB event ([ ]a,c,e psi) relative to NOP ([ ] ac,e psi) with primary and secondary side temperatures as low as 212OF when comparing contact pressures for NOP conditions for the unit cell to contact pressures for SLB for the unit cell.Again, referring to Table RAI4-6, it has been shown when comparing contact pressures for NOP conditions for the unit cell to contact pressures for SLB for the unit cell for the Model F SG (higher temperature SLB conditions), that contact pressure increases during a postulated SLB (from [ a,c,e psi at NOP to [ ] a,c,e psi at SLB).36 L TR-SGMP-09-109 NP-Attachment


===2.4 Relative===
LLTR-SGMP-09-109  NP-Attachment TR-SGMP-09-109 NP-Attachment Conservatism of "Old" and "New" 2.4 Relative Conservatism                                        "New" FitFit I lf both old and new models are I              conservatism of the methods?
Conservatism of "Old" and "New" Fit I lf both old and new models are conservative, is there an appropriate basis to show the relative conservatism of the methods? Response:
relative conservatism relative are conservative, conservative,is there methods?
As noted above in Section 1.3 of this response, tube bore dilation is a more significant factor in determining tube-to-tubesheet contact pressure at higher temperatures and the effect of eccentricity on contact pressure is reduced at higher temperatures.
an appropriate there an    appropriate basis basis to show the
The methodology for addressing the effect of eccentricity on contact pressure discussed in Reference 6-15 and utilized in WCAP-17071-P, WCAP-17072-P, WCAP-17091-P and WCAP-17092-P reflects this fact and it, therefore, provides acceptably accurate contact pressure results at higher temperatures (Le., for all conditions except the "colder" SLB condition).
This includes NOP, SLB (higher temperature, > 400&deg;F, and FLB, where appropriate).
Also, as noted in Section 1.3 of this report, the effect of eccentricity on contact pressure loss is a more significant factor at the lower SLB temperatures for the Model D5 SG, but tube bore dilation due to temperature and pressure needs to be considered (which was not addressed in the "new" method, a.k.a the White Paper method discussed in WCAP-17072-P or 17091-P).
Moreover, the original 3rd order polynomial fit significantly over-predicts contact pressure loss during the "colder" Model D5 SLB transient (and Model 44F two loop plant SLB). Therefore, a more detailed model for contact pressure during a postulated SLB was developed.
Referring to Table RAI4-6, it shows that contact pressure increases during a SLB event ([ ]a,c,e psi) relative to NOP ([ ] a.c,e psi) with primary and secondary side temperatures as low as 212&deg;F when comparing contact pressures for NOP conditions for the unit cell to contact pressures for SLB for the unit cell. Again, referring to Table RAI4-6, it has been shown when comparing contact pressures for NOP conditions for the unit cell to contact pressures for SLB for the unit cell for the Model F SG (higher temperature SLB conditions), that contact pressure increases during a postulated SLB (from [ ] a,c,e psi at NOP to [ ] a,c,e psi at SLB). 36 LTR-SGMP-09-109 NP-Attachment


===3.0 Comparison===
===Response===
As noted above in        in Section 1.3 of this response, tube bore dilation is a more significant factor in          in determining        tube-to-tubesheet determining tube-to-tubesheet              contact      pressure  at  higher    temperatures temperatures    and  the  effect  of eccentricity on contact pressure eccentricity                        pressure is reduced at higher temperatures. The methodology for addressing the effect of eccentricity addressing                          eccentricity on contact contact pressure pressure discussed discussed in in Reference Reference 6-15 and utilized    in WCAP-17071-P, utilized in WCAP-17071-P,              WCAP-17072-P,            WCAP-17091-P WCAP-17091-P and WCAP-17092-P WCAP-17092-P reflects thisthis fact and it,  it, therefore, provides acceptably acceptably accurate accurate contact pressure results at higher temperatures (Le.,
temperatures        (i.e., for all conditions except the "colder" "colder" SLB condition).
condition). This includes NOP, SLB (higher (higher temperature, >          4000 F, and FLB, where appropriate).
                                > 400&deg;F,                          appropriate).
Also, as noted in    in Section Section 1.3 of this report, the effect of eccentricity eccentricity on contact pressure pressure loss is a more significant factor at the lower SLB temperatures for the Model D5 SG, but tube bore dilation due to temperature temperature and pressure needs to be considered (which was not addressed in                    in "new" method, a.k.a the White Paper method discussed in the "new"                                                                              WCAP-17072-P or 17091-P).
in WCAP-17072-P        17091-P).
Moreover, the original 3rd order polynomial fit significantly over-predicts    over-predicts contact pressure    loss pressure loss during the "colder" "colder" Model Model D5 SLB transient (and Model 44F two loop plant SLB).
Therefore, a more  more detailed detailed model for contact pressure pressure during a postulated SLB was developed.
developed.
Referring to Table RAI4-6, itit shows that contact pressure increases Referring                                                                              increases during a SLB event
([
([
          ]a,c,e psi) relative to NOP ([
          ]a,c,e psi) relative to NOP ([
                                                    ] ac,e psi) with primary and secondary side temperatures as
                                                    ] a.c,e psi) with primary and secondary side temperatures as low as 212OF 212&deg;F when comparingcomparing contact pressures for NOP conditions  conditions for the unit cell to contact pressures pressures for SLB for the unit cell.
Again, referring to Table RAI4-6,  RAI4-6, itit has has been shown when comparingcomparing contact pressures pressures for NOP NOP conditions for the unit cell to contact pressures conditions                                              pressures for SLB for the unit cell for the Model F SG (higher temperature temperature SLB conditions), that contact pressure increases          increases during aa postulated postulated SLB (from ((        a,c,e psi at NOP to ((
                ] a,c,e                          ] a,c,e psi at SLB).
36


of 3D FEA and Unit Cell Model Results The eccentricities included in Table RAI 4-4 appear larger than anticipated.
LLTR-SGMP-09-109 TR-SGMP-09-1 09 NP-Attachment NP-Attachment 3.0 Comparison of 3D FEA and Unit Cell Model            Model Results Results The eccentricities eccentricitiesincluded included in Table Table RAI 4-4 appear appearlarger larger than anticipated.
Need to confirm that positive contact pressure exists around the entire circumference of the tube and state this clearly in the response.Response: Comparison of the eccentricity values calculated using the unit cell model (see Table RAI4-5)with the eccentricity values calculated from the 3D FEA model (see Table RAI4-1) shows that the eccentricities from both models are comparable.
anticipated. Need to confirm that positive positive contact contact pressure pressure    exists around around  the entire circumference entire  circumference of the tube and state and  state this this clearly clearly inin the response.
It is not reasonable to expect exact matches of numbers between the two models, however, the order of magnitude of the eccentricities calculated is the same. Given that the two structural models provide similar eccentricities, the unit cell model shows that for these eccentricities, positive contact pressure exists between the tubes and the tubesheet for the entire range of displacements considered.
response.
Further, the results show that the contact pressures at SLB conditions exceed those at NOP conditions.


===4.0 Additional===
===Response===
Comparison Comparison of the eccentricity eccentricity values calculated using the unit cell model model (see Table RAI4-5) eccentricity values calculated with the eccentricity            calculated from the 3D FEA model (see Table RAI4-1)    RAI4-1) shows that the eccentricities eccentricities  from    both models are comparable. ItIt is not reasonable reasonable to expectexpect exact matches of numbers between the two models, however, the order of magnitude of the                            the eccentricities eccentricities calculated calculated is the same. Given that the two structural models provide similar            similar eccentricities, eccentricities, the unit cell model shows that for these eccentricities, positive contact pressure    pressure exists between between the tubes and the tubesheet for the entire range of displacements displacements considered.
Further, the results show that the contact pressures pressures at SLB conditions exceed those at NOP        NOP conditions.
4.0 Additional Background        Information For Key Questions Background Information                    Questions and Issues Issues RAI#4 RAI#4 evolved evolved inin several stages, each stage building on the prior stage. ReferenceReference 10 provided additional questions additional  questions to augment those that were provided by Reference    Reference 5. Responses Responses were prepared prepared  and  were    discussed discussed in  in a telephone  conference telephone conference      on  August  11, 11, 2009., During 2009. During this this telephone conference, additional questions questions were raised as identified identified in in the introduction introduction of this this document. The following are responses that were provided in                                Reference 10 that in response to Reference were discussed in in the  August    11, 11,  2009  telephone conference.
conference. They  are  historical  in nature and historical in are provided to complete the record of information provided in      in response to the NRC request for additional information.
information.
Comparison of "Old and New" 4.1 Comparison                        New" Relationship Relationship for Reduction in Contact Pressure and            and Eccentricity Eccentricity In Figure Figure 2 of the White Paper,Paper, add a plot for original originalrelationship relationshipbetween reductionsreductions in contact pressure contact  pressure and and eccentricity eccentricity as given in Reference 6-15 in      in the graph      accompanying graph accompanying Table 6-3. Explain Table        Explain why this original original relationship relationship remains    conservative in light remains conservative            light of the new relationship. Explain relationship. Explain the reasons reasonsfor the differences between the curves. curves.
In order to superimpose In          superimpose the results of the "old" and "new" analyses  analyses for reduction reduction in in contact pressure related to eccentricity, the data for the "old" method mList    must be normalized normalized in  in the same fashion that Figure 2 has been normalized. The plot of contact contact pressure reduction included in      in 37


Background Information For Key Questions and Issues RAI#4 evolved in several stages, each stage building on the prior stage. Reference 10 provided additional questions to augment those that were provided by Reference
LLTR-SGMP-09-109 TR-SGMP-09-109 NP-Attachment NP-Attachment Figure 22 of the White Paper Figure                              represents the total reduction in contact pressure associated Paper represents                                                              associated with a eccentricity. The information given eccentricity.            information from Table 6-3 represents  represents the ratio        of the  contact pressure calculated at aa given eccentricity calculated                eccentricity divided divided by the contact pressure calculated for a tubesheet        tubesheet bore with no eccentricity. For the new analysis, the total reduction              reduction      in contact    pressure  for the the eccentricities eccentricities (OMAX        OMIN) for (DMAx - DMIN)        a  range    of  up  to  [                inch  is  determined
: 5. Responses wereprepared and were discussed in a telephone conference on August 11, 2009. During this telephone conference, additional questions were raised as identified in the introduction of this document.
                                                                          ]a,c,e inch is determined to be [
The following are responses that were provided in response to Reference 10 that were discussed in the August 11, 2009 telephone conference.
                                                                          ]a,c,e                          to be [      ]a,c,e
They are historical in nature and are provided to complete the record of information provided in response to the NRC request for additional information.
                                                                                                                          ]a,c,e psi. For the old analysis, the total reduction in contact pressure for eccentricities          eccentricities in the same range is calculated calculated to be [          ]a,c,e psi. The normalization
                                      ]a,c,e                normalization basis is the same for both curves      curves on the figure.
Figure RAI4-11, RAI4-11, showing showing the normalized normalized results as discussed  discussed during the August 17, 2009 meeting, is provided below. (Figure RA14-11      RAI4-11 is the same as Figure RA14-10        RAI4-10 in Section 2.1 of this document, except that the values of the "Old Polynomial Results" have been corrected                      corrected on Figure Figure RA14-10 RAI4-10 by a factor factor of 2 as discussed in the August 17, 2009 meeting.) The curve                        curve labeled labeled "Old" Model Results Results is based on the data from Table RAI4-3            RA14-3 (Table 6-2 of Reference 15 of the WCAP report). The curve labeled "New" Model                        reproduces Figure 22 in the White Model reproduces                              White Paper (Reference 12). The curve labeled "D5 (Reference                                            "05 SLB Polynomial Polynomial Fit" are the results when        when thethe eccentricity data and ADhole eccentricity                  ,10hole for the Model D5        05 SLB condition are applied      applied directly to the  the polynomial fit, equation 6-8 in WCAP-17072-P and similar equation                          equation    on    page  6-85    in WCAP-17071-P.
WCAP-17071-P. The latter curve is based          based on the maximum displacement  displacement conditions at the top of the tubesheet for the Model D5. 05.
The curve labeled "Old Model Results" (top curve on Figure                          RAI4-1 1) is misleading relative to Figure RAI4-11) making an assessment assessment of the conservatism of the new                new analysis method compared  compared to the old  old analysis method.
analysis  method. UnlikeUnlike the new analysis method, which is only applied to the SLB case for the                      the Model D5 05 SGs, the old analysis method has not been applied as a linear function                              function asas represented represented in the figure as the uppermost curve (solid squares). In reality, the old data fit (top curve on Figure Figure RAI4-11),
RAI4-1 1), which is a 3rd order polynomial  polynomial fit, when extrapolated extrapolated significantly significantly outside its supported outside        supported data range (Le.,      (i.e., at temperatures temperatures either significantly significantly above or below 5000 F), provides 500&deg;F),  provides physically unrealistic unrealistic results as shown on Figure          Figure RA14-11 RAI4-11 (bottom curve, A-symbols). The Model 05        D5 SLB condition puts the tubesheet at a nearly uniform temperature          temperature of 3000 F, which is far outside of the range for which the eccentricity less than 300&deg;F,                                                                                          relationship was eccentricity relationship    was developed in Reference developed        Reference 6-15 in the WCAP reports.
The original relationship remains conservative                  because itit predicts greater reduction conservative because                                    reduction of tube to  to tubesheet tubesheet contact pressure pressure than the new method      method for all operating conditions. However, the              the original relationship relationship is only valid when ADmi,      ,10min and ,10max AlDmax are within [ ]a,c,a]a,c,e % and eccentricity eccentricity is within [    ]a,c,e inch to [ ]a,c,e inch range, (i.e.,
            ]a,c,e                                      (Le., the basis of the original fit).
The maximum tube bore distortions              occur at the top of the tubesheet. The results from applying distortions occur                                                                  applying the old fit for the relationship relationship versus the new fit for the relationship    relationship for the Model 05      D5 SLB tubesheet tubesheet displacements displacements and contact  contact pressures pressures are shown in Table RAI4-7. The tube-to-tubesheet (TITS)
(T/TS) contact pressure pressure result due  due to thermal expansion expansion of the tube and the pressure expansion of the tube including expansion                    including the effect of the crevice pressure distribution,  distribution, is the same in the  the both the "old" and "new""new" cases in the Table RA14-7    RAI4-7. .
38 38


===4.1 Comparison===
LTR-SGMP-09-109 L TR-SGMP-09-1 09 NP-Attachment NP-Attaehment RAI4-7 Table RA14-7 Summary of Model D5 Summary                  05 SLB Contact Pressure Results for        for Different Eccentricity Eccentricity Fit Relationships Relationships Model 05D5                                              T/TS  PCON Reduction TITS PeoN                                TITS PeoN T/TS  PCON Condition        Value          Eccentricity Eccentricity            Old                New              Old            New New 1a,c,e SLB          Avg Avg SLB          Max Max SLB          Min Min The results in Section 6.2.4 of WCAP-17071-P WCAP-17071-P and WCAP-17072-P WCAP-17072-P show that the average    average expected tubesheet-tube-bore        eccentricity is on the order of [
tubesheet-tube-bore eccentricity                                          ]a,c,e inch. The results Ia,c,e in Table  RAI4-7 show that the old method Table RA14-7                          method of calculating the reduction reduction in contact pressure due    due tubesheet-tube-bore eccentricity to tubesheet-tube-bore      eccentricity and change change in diameter is conservative conservative for larger larger values of eccentricity and b.0 eccentricity      AD (predicts greater greater decrease decrease in contact pressure) than the new fit. However, it is inappropriate inappropriate to use the old method at smaller values of eccentricity  eccentricity and AD  b.0 because it provides physically impossible results (see Table RAI4-7). For example, the "old" method predicts a larger larger decrease decrease in contact contact pressure for a smaller eccentricity eccentricity on the order of 10-  10-77 inch than for aa larger eccentricity eccentricity on the order          10-3 inch. The "new" order of 10-3                "new" method, method, by comparison, comparison, predicts aa slightly positive increase increase in contact                        eccentricity of 10-7 inch and a pressure for an eccentricity contact pressure large reduction reduction in contact pressure for an eccentricity of 10-        10-44 inch or greater, a    a physically physically realistic result. The reason that the "old" method predicts such a different reduction in contact pressure for small values of eccentricity eccentricity is that these small eccentricity eccentricity values values are well outside outside the range of the data upon which the "old" relationship relationship was  developed.
developed.      However,    when    used within its intended range of eccentricities eccentricities and tubesheet bore displacement, displacement, the "old" methodmethod provides valid and conservative conservative results. The "new" methodmethod of calculating calculating the reduction in T/TS  TITS contact contact  pressure  is  linear and  directly  accommodates directly accommodates      small calculated calculated  values    of eccentricity.
eccentricity. It is also clear from the results in Table RA14-7RAI4-7 that the results from the old method method when used in eccentricity range are highly conservative its supported eccentricity                        conservative compared compared to the "new" "new" method.
39 39


of "Old and New" Relationship for Reduction in Contact Pressure and Eccentricity In Figure 2 of the White Paper, add a plot for original relationship between reductions in contact pressure and eccentricity as given in Reference 6-15 in the graph accompanying Table 6-3. Explain why this original relationship remains conservative in light of the new relationship.
LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109  NP-Attachment a,c,e RAI4-11 Figure RA14-11 Original        RAI4-2 Discussed Original Figure RA14-2 Discussed at the August 17, 2009 Meeting Meeting 40 40
Explain the reasons for the differences between the curves.In order to superimpose the results of the "old" and "new" analyses for reduction in contact pressure related to eccentricity, the data for the "old" method must be normalized in the same fashion that Figure 2 has been normalized.
The plot of contact pressure reduction included in 37 L TR-SGMP-09-1 09 NP-Attachment  


===3.0 Comparison===
LLTR-SGMP-09-109      NP-Attachment TR-SGMP-09-1 09 NP-Attachment 4.2 Use of Both "Old" and "New"    "New" Fit  Fit When establishing establishing whether whether contact contact pressure pressure increases increases when going    going from normal normal operating to steam operating            steam line  break conditions, line break  conditions, how can    can a valid and  and conservative conservative comparison comparison be made if      if the normal    operating case normal operating        case is  based on the original is based              original delta delta contact      pressure contact pressure versus eccentricity eccentricity curve andand the SLB case  case isis based based on the new curve?


of 3D FEA and Unit Cell Model Results The eccentricities included in Table RAI 4-4 appear larger than anticipated.
===Response===
Need to confirm that positive contact pressure exists around the entire circumference of the tube and state this clearly in the response.
Response:
Response:
Comparison of the eccentricity values calculated using the unit cell model (see Table RAI4-5) with the eccentricity values calculated from the 3D FEA model (see Table RAI4-1) shows that the eccentricities from both models are comparable.
It is important to note than the new analysis method        method is only used for the SLB condition condition for thethe Model D5    05 steam                  Comparison of contact steam generators. Comparison              contact pressures between              normal operating between the normal        operating condition condition and the SLB condition is made        made for the Model F steam generators generators in the H* fleet in    in WCAP-17071-P WCAP-1 7071-P on a consistentconsistent basis.
It is not reasonable to expect exact matches of numbers between the two models, however, the order of magnitude of the eccentricities calculated is the same. Given that the two structural models provide similar eccentricities, the unit cell model shows that for these eccentricities, positive contact pressure exists between the tubes and the tubesheet for the entire range of displacements considered.
ItIt is Westinghouse's        engineering judgment Westinghouse's engineering          judgment that the old methodology provides an accurate          accurate determination of contact pressures during determination                                  during normal operating operating conditions conditions and postulated accident accident conditions (FLB and SLB) when peak temperatures conditions                                            temperatures range between between [                      of and
Further, the results show that the contact pressures at SLB conditions exceed those at NOP conditions.  
                                                                                                        ]a,c,e OF
                                                                                                        ]a.c.e eccentricities eccentricities are betweenbetween ((      ]a.c.e inch and ((
                                          ]a,c,e                    ]a.c.e inch and Dmax
                                                                    ]a,c,e              Omax and Omin          within Dmin are within
      ]a.c.e % of each
[I]a,c,e          each other.
Application of the new method Application                    method to calculate eccentricities eccentricities and values of Dmax  Omax and Omin Dmin that fall outside outside the above noted                                conservative results because the plane noted range provides conservative                                    plane strain model upon upon which it based  based over-estimates over-estimates the stiffness stiffness of the tube and tubesheet tubesheet structure structure leading leading toto lower contact pressure results as a function of eccentricity. The new method            method also excluded excluded the the effect effect of temperature                          conservatively bounds the lower temperatures of the Model temperature and therefore, conservatively D5 SLB transient. The TITS 05                              T/TS contact contact pressure pressure results during during SLB are still expected expected to bound bound thethe T/TS      contact TITS contact          pressure  results  during    NOP    because,    even    though    the tube  bore  eccentricity eccentricity during SLB is generally greater during                          greater than that during NOP, the overall growth    growth of the tube bore during NOP NOP is greatergreater than that during SLB. Larger magnitudes magnitudes of tube bore growth growth are directly directly related decreasing tube-tubesheet to decreasing        tube-tubesheet contact contact pressure pressure regardless of the value of calculated calculated tube borebore eccentricity.
It is appropriate appropriate to compare the Model 05        D5 SLB contact pressure pressure results from the "new""new" method to the Model  Model D5 05 NOP results from the "old" method                  because each condition method because                condition uses the  the appropriate fit to conservatively appropriate                              determine the reduction in T/TS conservatively determine                            TITS contact pressure due to tube    tube bore eccentricity bore      eccentricity and tube bore growth.
The sole purpose of the new methodologymethodology was to develop a more accurate      accurate way of calculating calculating contact pressures during    during a postulated postulated SLB for the Model 05            D5 steam steam generators.
generators. The    The comparison comparison provided in Figure 6-83 of WCAP-17072-P WCAP-17072-P remains a valid comparison.
41
 
LLTR-SGMP-09-109  NP-Attachment TR-SGMP-09-1 09 NP-Attachment 5.0 Part A (Original RAI#4)
Reference 1, Page                                          concluded that the tube Page 6-69: In Section 6.2.5.3, it is concluded                                  diameter tube outside diameter and the tubesheet and      tubesheet tube bore bore inside inside diameter              maintaincontact diameter always maintain        contact in the predicted predicted range of tubesheet range      tubesheet displacements.
displacements. However, However, for tubes with through-wall        cracks at through-wallcracks    at the H*
H*
: distance, distance, there there may be little or no net pressure pressureacting acting on the tube for some distance distance above H*. In Tables 6-18  6-18 and 6-19, the fourth fourth increment increment in the step that occurs two steps prior          last step suggests prior to the last        suggests thatthat there there may be no contact contact between the tube and tubesheet, over a portion tubesheet,                              circumference, for a distance portion of the circumference,              distance above above H*. Is the conclusion conclusion in 6.2.5.3 6.2.5.3 valid valid for for the entire entire H*H* distance, distance,given the possibility possibility that that the tubes may contain contain through-wall through-wall cracks cracks at at that location?
location?
The following response to RAI#4 was included              Reference 11.
included in Reference    11. The same response is included included here here to complete complete the record          information provided record of information      provided in regard to RAI#4 of References References 5, 6 and 7.
 
===Response===
The conclusions conclusions reached reached inin Section Section 6.2.5.3 of WCAP-17071-P are valid for the entire H*          H*
distance because distance  because of the following considerations:
: 1. The primary source of contact pressure      pressure between between the tube and the tubesheet is differential thermal expansion expansion between between the tubes and the tubesheet. The analysis in specifically excludes the effect of thermal expansion Section 6.2.5.3 specifically                                        expansion of the tube from the the analysis. The tubesheet is assumed to deform    deform due to the combination of pressure and  and thermal loads which produces produces the tube bore ovalization ovalization and leads to the displacements displacements applied in this model. Only the residual effects from installation are considered for the        the tube in steps 1 through through 5. The tube internal pressure applied in these steps only simulates the hydraulic expansion pressure simUlates                                    pressure to establish the initial conditions for thethe following step. The conditions conditions assumed for this study are not possible during    during any operating operating condition in the steam          generator but are conservative steam generator              conservative relative to actual SG conditions. (Note: Residual Residual contact pressure pressure is not used used in the calculation of H*  values H* values in Section 6. The residual effects of installation are included included in the results of Section Section 6.2.5.3 so that the sensitivity of aa strain hardened  hardened tube to tubesheet tubesheet tube bore deformation deformation can be studied.)
: 2. Step 5 on Tables 6-18 and 6-19 is not representative of any condition in the steam generator because generator    because itit assumes assumes that the tubesheet is at operating operating temperature with an applied applied primary-to-secondary primary-to-secondary pressure differential while the tubes remain at room temperature and are not pressurized.
temperature                    pressurized. That is why Steps 1 through 5 are described described asas "initializing" steps in the process. ItIt is physically impossible for these conditions conditions to occur simultaneously simultaneously in the same steam generator.
42
 
LTR-SGMP-09-109 LTR-SGMP-09-1 09 NP-Attachment NP-Attachment Because no pressure
: 3. Because        pressure loading loading is applied to the tube in Step 5 of the analysis analysis discussed discussed inin section 6.2.5, the results presented in Tables 6-18 and 6-19 are applicable  applicable regardless of whether, or not, aa through-wall crack exists at the H*      H* location.              representative location. The more representative case is Step 6 shown on Tables 6-18 and 6-19 in which tube internal                        pressure is internal pressure included. For that case, the potential point of zero contact pressure included.                                                                pressure is at an applied applied displacement a factor of 5 greater displacement                        greater than for Step 5, and far in excess    excess of what is predicted for the actual tubesheet deformation. The factor of 5 difference in reasonably predicted                                                                                  in displacement to cause the contact pressure to reduce to zero more than required displacement adequately covers the postulated adequately                                                reduction in crevice pressure due to a postulated potential local reduction circumferential  separation circumferential separation      at the  location  of  H*. Recall  also, that no thermal expansion expansion of the tube is considered in  in this analysis.
ItIt is also noted noted that tables 6-18 and 6-19 are the resultsresultsofof a sensitivity study that is not intended to represent          integrated calculation for H*.
represent the integrated                      H*. The integrated integrated H*
H* analysis is a complex      process complex process that combines combines the effects of several types of loading and deformation    deformation into an integrated estimate of the tube-to-tubesheet estimate                                                                              appropriate to consider aa tube-to-tubesheet contact pressure. Therefore, it is not appropriate context of the greater analysis.
sensitivity study out of the context sensitivity                                                                  integrated analysis analysis. The integrated                presented in analysis presented    in the complete complete Section 6 shows shows that for the combined case of the thermal effects, pressure effects, and tubesheet displacement                      tube-to-tubesheet contact pressure throughout the displacement there is tube-to-tubesheet                                          the tubesheet.
It      acknowledged that the cut end of a tube is radially less stiff than a tube that is radially It is acknowledged                                                                                        radially loaded at a point away from the tube end, and that the presumption loaded                                                                presumption of a tube sever at the H*    H*
distance may represent the case of a tube end. The decreased distance                                                          decreased tube-end stiffness is referred to as "compliance." In    In other other words, a tube that is loaded at the cut end provides less resistance to the load than a tube with equal load applied a distance removed from the tube-end. Thus, conceptually, a local "end effect" could be expected conceptually,                                        expected to occur due to the increased        compliance of increased compliance the tube-end.
tube-end.
calculation process for H*
The calculation                    H* shown shown in Figure 1-1  1-1 of the H*    WCAP reports and discussed in H* WeAP several places in the report notes that an adjustment adjustment is made to the initial prediction of H*    H* to account for the distributed account              distributed crevice pressure referenced                predicted H*
referenced to the predicted      H* position. Thus, thethe greatest crevice crevice pressure is always located at the final value of H*. Increased tube compliance  compliance cannot result in a higher higher local crevice    pressure than is already included in the analysis because, crevice pressure                                                  because, at the point of sever, the primary side pressure pressure is the crevice crevice pressure.
increased tube compliance postulated that the increased It may be postulated                                      compliance results in reduced reduced contact pressure because              differential pressure across because the net differential                                                              tube-end, the current across the tube wall is zero. At the tube-end,              current analysis already includes includes aa zero differential differential pressure due to the adjustment            process for adjustment process distributed crevice pressure. Therefore, the net reduction in contact pressure      pressure would be limited length of the local effect and would further depend to the axial length                                                  depend on the slope of the decrease decrease in in crevice pressure.
Model F and Model D5 For the Model                      05 SGs, the bounding                              distance above the tube bounding value of isolation distance                    tube end is 0.6 inch based on classical solutions for the design of pressure vessels (Timoshenko).
43


===4.0 Additional===
LLTR-SGMP-09-109        NP-Attachment TR-SGMP-09-1 09 NP-Attachment isolation distance The isolation                          generically applicable distance is the generically                                      separation distance from an applicable minimum separation applied load to a point of interest in order to safely safely assume that the load is in    in the far field relative Specific structures and load cases may have different to the point of interest. Specific                                                                          distances different isolation distances but the classical result by Timoshenko Timoshenko for a pressure vessel will conservatively conservatively bound any specific cases. For this length, the slope of the contact pressure  pressure curve would                    decrease would have to decrease by aa factor factor of at least (( ]a,c,e
                              ]a.c.e before the value of H* H* is affected affected by more more than [        ]ace inch.
                                                                                                        ]a.c.e  inch. IfIf conservatively modeled as a center-loaded the tube is conservatively                                                                  foundation compared center-loaded beam on an elastic foundation              compared end-loaded beam on an elastic to an end-loaded                      elastic foundation, the resulting worst case change    change in structural compliance compliance and the resulting contact pressure slope could be a factor of up to 2. Alternatively, similar analyses for the cross sections of curved  curved beams suggest that the change    change in compliance compliance of the structure structure could be as high as a factor factor of 6. Neither case approaches approaches the factor of (( 1]a.c.e    ",c,e based on classical required based                                          analysis to impact the value of H*; therefore, no classical pressure vessel analysis                                                            no adjustments to H*
additional adjustments        H* are necessary          address the potential end effects.
necessary to address 6,0                      Response to RAI #4 6.0 Summary of the Response A summary of the response to the original RAI#        RAI# 4 and additional      questions related to RAI 4 are additional questions provided provided below:
adjustment to the value for H*
: 1. No additional adjustment
: 1.                                                            necessary to address the potential H* is necessary for end effects. This is because the greatest crevice    crevice pressure pressure is always located at the final value of H*. At the H*    H* distance, the current analysis already            includes already includes aa zero pressure differential due to the adjustment process for the distributed crevice pressure. Therefore, the net reduction in              in contact pressure pressure would be      be limited to the axial length of the local effect and would further depend on the                    the slope of the decrease decrease in                                    judged that the slope of the in crevice pressure. ItIt is judged                                  the contact pressure curve would not decrease at aa rate such that the value of H*                      H*
would be affected.
affected.
dilation is a more significant factor in determining
: 2. Tube bore dilation                                                              tube-to-tubesheet determining tube-to-tubesheet pressure at higher contact pressure contact                            temperatures and the effect higher temperatures                  effect of eccentricity eccentricity on contact pressure pressure is reduced reduced at higher temperatures. The methodology methodology for addressing the      the effect of eccentricity on contact pressure discussed                      Reference 6-15 and discussed in Reference utilized utilized in    WCAP-17071-P, WCAP-17072-P, in WCAP-17071-P,                                  WCAP-17091-P and WCAP-WCAP-17072-P, WCAP-17091-P 17092-P reflects this fact and, therefore, itit provides acceptably 17092-P                                                                        accurate contact acceptably accurate pressure pressure results at higher temperatures          (i.e., for all conditions temperatures (i.e.,            conditions except the "colder""colder" 0 F, SLB condition). This includes NOP, SLB (higher temperature,  temperature, > 400 400&deg;F,    and FLB, where appropriate).
described in Reference 6-15 match
: 3. The results of using the fit described                                match the expected expected trend from a best case finite element model for the NOP and SLB conditions for the                        the Model F SGs and NOP conditions for the Model      Model D5 05 SG.
: 4. The ~Os ADs from the 3D  30 FEA model are significantly less than the corresponding corresponding ADs from the unit cell model from the unloaded to the fully loaded
                ~Os                                                                        loaded condition (i.e.,(i.e.,
44


Background Information For Key Questions and Issues RAI#4 evolved in several stages, each stage building on the prior stage. Reference 10 provided additional questions to augment those that were provided by Reference
LTR-SGMP-09-109 L TR-SGMP-09-1 09 NP-Attachment NP-Attachment from step 0 to step 9) for both NOP and SLB conditions. This leads to the                the conclusion that the unit cell model displacement displacement results and contact pressure conservatively represent the reference 3D FEA model predictions conservatively                                        model results.
: 5. Responses were prepared and were discussed in a telephone conference on August 11, 2009., During this telephone conference, additional questions were raised as identified in the introduction of this document.
: 5. The eccentricities eccentricities from the unit cell model are generally comparable to those from the 3D FEA model.model. A more exact comparison is difficult based      based on the the available data; data; however, itit is clear that the actual range of eccentricities eccentricities from thethe 3D FEA model was adequately adequately addressed addressed by the unit cell model.
The following are responses that were provided in response to Reference 10 that were discussed in the August 11, 2009 telephone conference.
model.
They are historical in nature and are provided to complete the record of information provided in response to the NRC request for additional information.  
: 6. Based on items 4) and 5) which demonstrate demonstrate the acceptability acceptability of the use of thethe unit cell model model for benchmarking benchmarking the 3-D FEA model, the method for calculating  calculating the reduction in contact pressure pressure defined                      model, when adjusted defined by the unit cell model, for temperature temperature effects, shows that SLB contact contact pressure is increased increased relative to operating conditions for the Model 05 normal operating                                D5 steam generators.
: 7. ItIt has also been shown when comparing                      pressures for NOP conditions comparing contact pressures                  conditions for the unit cell to contact pressures for SLB for the unit cell for the Model F SG (higher temperature temperature SLB conditions), that contact pressurepressure increases increases during a postulated SLB.
postulated
: 8. Given that the two structural models provide similar eccentricities, eccentricities, the unit cell model model shows that for these eccentricities, positive contact pressure exists between between the tubes and the tubesheet tubesheet for the entire entire range of displacements displacements considered.
considered.
Based on the above, itit is concluded concluded that the NOP NOP contact pressures that define define H*H* in the Model F and Model 05  D5 SG are conservative conservative and that a more realistic model of contact pressure reduction reduction as a function of tube bore deformation (including both dilation and eccentricity) eccentricity) would predict predict positive contact  pressure around the entire circumference contact pressure                        circumference of the tube and an increase increase inin tube to tubesheet tubesheet contact pressure                            compared to NOP conditions.
pressure at SLB conditions compared The conclusions conclusions reached in the response response to RAI#4 apply equally for the Model 44F and Model 51IF 51F SGs.
45


===4.1 Comparison===
Vogtle Electric Generating Generating Plant Units 1 and 2 Response to Request Response      Request for Additional Information Related Related to License License Amendment Amendment Request Request to Revise Technical Specification Specification (TS)
Sections Sections 5.5.9, "Steam Generator        Program" and TS 5.6.10, "Steam Generator (SG) Program"                  "Steam Generator      Inspection Report" for Permanent Generator Tube Inspection                                            Criteria Permanent Alternate Repair Criteria Enclosure 3 Enclosure Westinghouse Westinghouse Electric Company Company LLC, CAW-09-2661, CAW-09-2661, "Application for Withholding Proprietary Information "Application                              Information from Public Public Disclosure" Disclosure"


of "Old and New" Relationship for Reduction in Contact Pressure and Eccentricity In Figure 2 of the White Paper, add a plot for original relationship between reductions in contact pressure and eccentricity as given in Reference 6-15 in the graph accompanying Table 6-3. Explain why this original relationship remains conservative in light of the new relationship.
e)
Explain the reasons for the differences between the curves. In order to superimpose the results of the "old" and "new" analyses for reduction in contact pressure related to eccentricity, the data for the "old" method mList be normalized in the same fashion that Figure 2 has been normalized.
* Westinghouse Westinghouse Westinghouse Electric Company Westinghouse Nuclear Services Services P.O. Box 355 355 Pittsburgh.
The plot of contact pressure reduction included in 37 LTR-SGMP-09-109 NP-Attachment Figure 2 of the White Paper represents the total reduction in contact pressure associated with a given eccentricity.
Pittsburgh, Pennsylvania 15230-0355 15230-0355 USA U.S. Nuclear Nuclear Regulatory Commission                                Directtel: (412)
The information from Table 6-3 represents the ratio of the contact pressure calculated at a given eccentricity divided by the contact pressure calculated for a tubesheet bore with no eccentricity.
(412)374-4643 374-4643 Document Control Desk                                              Directfax:
For the new analysis, the total reduction in contact pressure for the eccentricities (DMAx -DMIN) for a range of up to [ ]a,c,e inch is determined to be [ ]a,c,e psi. For the old analysis, the total reduction in contact pressure for eccentricities in the same range is calculated to be [ ]a,c,e psi. The normalization basis is the same for both curves on the figure.Figure RAI4-11, showing the normalized results as discussed during the August 17, 2009 meeting, is provided below. (Figure RAI4-11 is the same as Figure RAI4-10 in Section 2.1 of this document, except that the values of the "Old Polynomial Results" have been corrected on Figure RAI4-10 by a factor of 2 as discussed in the August 17, 2009 meeting.) The curve labeled "Old" Model Results is based on the data from Table RAI4-3 (Table 6-2 of Reference 15 of the WCAP report). The curve labeled "New" Model reproduces Figure 2 in the White Paper (Reference 12). The curve labeled "D5 SLB Polynomial Fit" are the results when the eccentricity data and ADhole for the Model D5 SLB condition are applied directly to the polynomial fit, equation 6-8 in WCAP-17072-P and similar equation on page 6-85 in WCAP-17071-P.
Direct fax: (412) 374-3846 374-3846 Washington, DC 20555-0001                                              e-mail: greshaja@westinghouse.com greshaja@westinghouse.com Our ref.
The latter curve is based on the maximum displacement conditions at the top of the tubesheet for the Model D5.The curve labeled "Old Model Results" (top curve on Figure RAI4-1 1) is misleading relative to making an assessment of the conservatism of the new analysis method compared to the old analysis method. Unlike the new analysis method, which is only applied to the SLB case for the Model D5 SGs, the old analysis method has not been applied as a linear function as represented in the figure as the uppermost curve (solid squares).
ref: CAW CAW-09-2661 2661 August 27, 20092009 APPLICATION APPLICA nON FOR WITHHOLDING WITHHOLDING PROPRIETARY PROPRIETARY INFORMATION INFORMATION FROM                      DISCLOSURE FROM PUBLIC DISCLOSURE LTR-SGMP-09-109 P-Attachment, "Response
In reality, the old data fit (top curve on Figure RAI4-1 1), which is a 3rd order polynomial fit, when extrapolated significantly outside its supported data range (i.e., at temperatures either significantly above or below 500 0 F), provides physically unrealistic results as shown on Figure RAI4-11 (bottom curve, A-symbols).
The Model D5 SLB condition puts the tubesheet at a nearly uniform temperature of less than 300 0 F, which is far outside of the range for which the eccentricity relationship was developed in Reference 6-15 in the WCAP reports.The original relationship remains conservative because it predicts greater reduction of tube to tubesheet contact pressure than the new method for all operating conditions.
However, the original relationship is only valid when ADmi, and AlDmax are within [ ]a,c,e % and eccentricity is within [ ]a,c,e inch to [ ]a,c,e inch range, (i.e., the basis of the original fit).The maximum tube bore distortions occur at the top of the tubesheet.
The results from applying the old fit for the relationship versus the new fit for the relationship for the Model D5 SLB tubesheet displacements and contact pressures are shown in Table RAI4-7. The tube-to-tubesheet (T/TS) contact pressure result due to thermal expansion of the tube and the pressure expansion of the tube including the effect of the crevice pressure distribution, is the same in the both the "old" and "new" cases in the Table RAI4-7.38 L TR-SGMP-09-109 NP-Attachment Figure 2 of the White Paper represents the total reduction in contact pressure associated with a given eccentricity.
The information from Table 6-3 represents the ratio of the contact pressure calculated at a given eccentricity divided by the contact pressure calculated for a tubesheet bore with no eccentricity.
For the new analysis, the total reduction in contact pressure for the eccentricities (OMAX -OMIN) for a range of up to [ ]a,c,e inch is determined to be [ ]a,c,e psi. For the old analysis, the total reduction in contact pressure for eccentricities in the same range is calculated to be [ ]a,c,e psi. The normalization basis is the same for both curves on the figure. Figure RAI4-11, showing the normalized results as discussed during the August 17, 2009 meeting, is provided below. (Figure RA14-11 is the same as Figure RA14-10 in Section 2.1 of this document, except that the values of the "Old Polynomial Results" have been corrected on Figure RA14-10 by a factor of 2 as discussed in the August 17, 2009 meeting.)
The curve labeled "Old" Model Results is based on the data from Table RA14-3 (Table 6-2 of Reference 15 of the WCAP report). The curve labeled "New" Model reproduces Figure 2 in the White Paper (Reference 12). The curve labeled "05 SLB Polynomial Fit" are the results when the eccentricity data and ,10hole for the Model 05 SLB condition are applied directly to the polynomial fit, equation 6-8 in WCAP-17072-P and similar equation on page 6-85 in WCAP-17071-P.
The latter curve is based on the maximum displacement conditions at the top of the tubesheet for the Model 05. The curve labeled "Old Model Results" (top curve on Figure RAI4-11) is misleading relative to making an assessment of the conservatism of the new analysis method compared to the old analysis method. Unlike the new analysis method, which is only applied to the SLB case for the Model 05 SGs, the old analysis method has not been applied as a linear function as represented in the figure as the uppermost curve (solid squares).
In reality, the old data fit (top curve on Figure RAI4-11), which is a 3rd order polynomial fit, when extrapolated significantly outside its supported data range (Le., at temperatures either significantly above or below 500&deg;F), provides physically unrealistic results as shown on Figure RA14-11 (bottom curve, A-symbols).
The Model 05 SLB condition puts the tubesheet at a nearly uniform temperature of less than 300&deg;F, which is far outside of the range for which the eccentricity relationship was developed in Reference 6-15 in the WCAP reports. The original relationship remains conservative because it predicts greater reduction of tube to tubesheet contact pressure than the new method for all operating conditions.
However, the original relationship is only valid when ,10min and ,10max are within [ ]a,c,a % and eccentricity is within [ ]a,c,e inch to [ ]a,c,e inch range, (Le., the basis of the original fit). The maximum tube bore distortions occur at the top of the tubesheet.
The results from applying the old fit for the relationship versus the new fit for the relationship for the Model 05 SLB tubesheet displacements and contact pressures are shown in Table RAI4-7. The tubesheet (TITS) contact pressure result due to thermal expansion of the tube and the pressure expansion of the tube including the effect of the crevice pressure distribution, is the same in the both the "old" and "new" cases in the Table RA14-7 . 38 LTR-SGMP-09-109 NP-Attachment Table RAI4-7 Summary of Model D5 SLB Contact Pressure Results for Different Eccentricity Fit Relationships Model D5 T/TS PCON Reduction T/TS PCON Condition Value Eccentricity Old New Old New SLB Avg SLB Max SLB Min The results in Section 6.2.4 of WCAP-17071-P and WCAP-17072-P show that the average expected tubesheet-tube-bore eccentricity is on the order of [ Ia,c,e inch. The results in Table RAI4-7 show that the old method of calculating the reduction in contact pressure due to tubesheet-tube-bore eccentricity and change in diameter is conservative for larger values of eccentricity and AD (predicts greater decrease in contact pressure) than the new fit. However, it is inappropriate to use the old method at smaller values of eccentricity and AD because it provides physically impossible results (see Table RAI4-7). For example, the "old" method predicts a larger decrease in contact pressure for a smaller eccentricity on the order of 10-7 inch than for a larger eccentricity on the order of 10-3 inch. The "new" method, by comparison, predicts a slightly positive increase in contact pressure for an eccentricity of 10-7 inch and a large reduction in contact pressure for an eccentricity of 10-4 inch or greater, a physically realistic result. The reason that the "old" method predicts such a different reduction in contact pressure for small values of eccentricity is that these small eccentricity values are well outside the range of the data upon which the "old" relationship was developed.
However, when usedwithin its intended range of eccentricities and tubesheet bore displacement, the "old" method provides valid and conservative results. The "new" method of calculating the reduction in T/TS contact pressure is linear and directly accommodates small calculated values of eccentricity.
It is also clear from the results in Table RAI4-7 that the results from the old method when used in its supported eccentricity range are highly conservative compared to the "new" method.1 a,c,e 39 Model 05 Condition SLB SLB SLB L TR-SGMP-09-1 09 NP-Attaehment Table RA14-7 Summary of Model 05 SLB Contact Pressure Results for Different Eccentricity Fit Relationships TITS PeoN Reduction Value Eccentricity Old New Avg Max Min TITS PeoN Old New The results in Section 6.2.4 of WCAP-17071-P and WCAP-17072-P show that the average expected tubesheet-tube-bore eccentricity is on the order of [ ]a,c,e inch. The results in Table RA14-7 show that the old method of calculating the reduction in contact pressure due to tubesheet-tube-bore eccentricity and change in diameter is conservative for larger values of eccentricity and b.0 (predicts greater decrease in contact pressure) than the new fit. However, it is inappropriate to use the old method at smaller values of eccentricity and b.0 because it provides physically impossible results (see Table RAI4-7). For example, the "old" method predicts a larger decrease in contact pressure for a smaller eccentricity on the order of 10-7 inch than for a larger eccentricity on the order of 10-3 inch. The "new" method, by comparison, predicts a slightly positive increase in contact pressure for an eccentricity of 10-7 inch and a large reduction in contact pressure for an eccentricity of 10-4 inch or greater, a physically realistic result. The reason that the "old" method predicts such a different reduction in contact pressure for small values of eccentricity is that these small eccentricity values are well outside the range of the data upon which the "old" relationship was developed.
However, when used within its intended range of eccentricities and tubesheet bore displacement, the "old" method provides valid and conservative results. The "new" method of calculating the reduction in TITS contact pressure is linear and directly accommodates small calculated values of eccentricity.
It is also clear from the results in Table RA14-7 that the results from the old method when used in its supported eccentricity range are highly conservative compared to the "new" method. 39 a,c,e LTR-SGMP-09-109 NP-Attachment a,c,e Figure RAI4-11 Original Figure RAI4-2 Discussed at the August 17, 2009 Meeting 40 LTR-SGMP-09-109 NP-Attachment a,c,e Figure RA14-11 Original Figure RA14-2 Discussed at the August 17, 2009 Meeting 40 LTR-SGMP-09-109 NP-Attachment 4.2 Use of Both "Old" and "New" Fit When establishing whether contact pressure increases when going from normal operating to steam line break conditions, how can a valid and conservative comparisonbe made if the normal operating case is based on the original delta contact pressure versus eccentricity curve and the SLB case is based on the new curve?
Response: It is important to note than the new analysis method is only used for the SLB condition for the Model D5 steam generators.
Comparison of contact pressures between the normal operating condition and the SLB condition is made for the Model F steam generators in the H* fleet in WCAP-1 7071-P on a consistent basis.It is Westinghouse's engineering judgment that the old methodology provides an accurate determination of contact pressures during normal operating conditions and postulated accident conditions (FLB and SLB) when peak temperatures range between [ ]a,c,e OF and eccentricities are between [ ]a,c,e inch and [ ]a,c,e inch and Dmax and Dmin are within I]a,c,e % of each other.Application of the new method to calculate eccentricities and values of Dmax and Dmin that falloutside the above noted range provides conservative results because the plane strain model upon which it based over-estimates the stiffness of the tube and tubesheet structure leading to lower contact pressure results as a function of eccentricity.
The new method also excluded the effect of temperature and therefore, conservatively bounds the lower temperatures of the Model D5 SLB transient.
The T/TS contact pressure results during SLB are still expected to bound the T/TS contact pressure results during NOP because, even though the tube bore eccentricity during SLB is generally greater than that during NOP, the overall growth of the tube bore during NOP is greater than that during SLB. Larger magnitudes of tube bore growth are directly related to decreasing tube-tubesheet contact pressure regardless of the value of calculated tube bore eccentricity.
It is appropriate to compare the Model D5 SLB contact pressure results from the "new" method to the Model D5 NOP results from the "old" method because each condition uses the appropriate fit to conservatively determine the reduction in T/TS contact pressure due to tube bore eccentricity and tube bore growth.The sole purpose of the new methodology was to develop a more accurate way of calculating contact pressures during a postulated SLB for the Model D5 steam generators.
The comparison provided in Figure 6-83 of WCAP-17072-P remains a valid comparison.
41 L TR-SGMP-09-1 09 NP-Attachment 4.2 Use of Both "Old" and "New" Fit When establishing whether contact pressure increases when going from normal operating to steam line break conditions, how can a valid and conservative comparison be made if the normal operating case is based on the original delta contact pressure versus eccentricity curve and the SLB case is based on the new curve? Response:
It is important to note than the new analysis method is only used for the SLB condition for the Model 05 steam generators.
Comparison of contact pressures between the normal operating condition and the SLB condition is made for the Model F steam generators in the H* fleet in WCAP-17071-P on a consistent basis. It is Westinghouse's engineering judgment that the old methodology provides an accurate determination of contact pressures during normal operating conditions and postulated accident conditions (FLB and SLB) when peak temperatures range between [ ]a.c.e of and eccentricities are between [ ]a.c.e inch and [ ]a.c.e inch and Omax and Omin are within [ ]a.c.e % of each other. Application of the new method to calculate eccentricities and values of Omax and Omin that fall outside the above noted range provides conservative results because the plane strain model upon which it based over-estimates the stiffness of the tube and tubesheet structure leading to lower contact pressure results as a function of eccentricity.
The new method also excluded the effect of temperature and therefore, conservatively bounds the lower temperatures of the Model 05 SLB transient.
The TITS contact pressure results during SLB are still expected to bound the TITS contact pressure results during NOP because, even though the tube bore eccentricity during SLB is generally greater than that during NOP, the overall growth of the tube bore during NOP is greater than that during SLB. Larger magnitudes of tube bore growth are directly related to decreasing tube-tubesheet contact pressure regardless of the value of calculated tube bore eccentricity.
It is appropriate to compare the Model 05 SLB contact pressure results from the "new" method to the Model 05 NOP results from the "old" method because each condition uses the appropriate fit to conservatively determine the reduction in TITS contact pressure due to tube bore eccentricity and tube bore growth. The sole purpose of the new methodology was to develop a more accurate way of calculating contact pressures during a postulated SLB for the Model 05 steam generators.
The comparison provided in Figure 6-83 of WCAP-17072-P remains a valid comparison.
41 LTR-SGMP-09-109 NP-Attachment 5.0 Part A (Original RAI#4)Reference 1, Page 6-69: In Section 6.2.5.3, it is concluded that the tube outside diameter and the tubesheet tube bore inside diameter always maintain contact in the predicted range of tubesheet displacements.
However, for tubes with through-wall cracks at the H*distance, there may be little or no net pressure acting on the tube for some distance above H*. In Tables 6-18 and 6-19, the fourth increment in the step that occurs two steps prior to the last step suggests that there may be no contact between the tube and tubesheet, over a portion of the circumference, for a distance above H*. Is the conclusion in 6.2.5.3 valid for the entire H* distance, given the possibility that the tubes may contain through-wall cracks at that location?The following response to RAI#4 was included in Reference
: 11. The same response is included here to complete the record of information provided in regard to RAI#4 of References 5, 6 and 7.Response: The conclusions reached in Section 6.2.5.3 of WCAP-17071-P are valid for the entire H*distance because of the following considerations:1. The primary source of contact pressure between the tube and the tubesheet is differential thermal expansion between the tubes and the tubesheet.
The analysis in Section 6.2.5.3 specifically excludes the effect of thermal expansion of the tube from the analysis.
The tubesheet is assumed to deform due to the combination of pressure and thermal loads which produces the tube bore ovalization and leads to the displacements applied in this model.
Only the residual effects from installation are considered for the tube in steps 1 through
: 5. The tube internal pressure applied in these steps only simulates the hydraulic expansion pressure to establish the initial conditions for the following step. The conditions assumed for this study are not possible during any operating condition in the steam generator but are conservative relative to actual SG conditions. (Note: Residual contact pressure is not used in the calculation of H* values in Section 6. The residual effects of installation are included in the results of Section 6.2.5.3 so that the sensitivity of a strain hardened tube to tubesheet tube bore deformation can be studied.)2. Step 5 on Tables 6-18 and 6-19 is not representative of any condition in the steam generator because it assumes that the tubesheet is at operating temperature with an applied primary-to-secondary pressure differential while the tubes remain at room temperature and are not pressurized.
That is why Steps 1 through 5 are described as"initializing" steps in the process. It is physically impossible for these conditions to occur simultaneously in the same steam generator.
42 L TR-SGMP-09-1 09 NP-Attachment 5.0 Part A (Original RAI#4) Reference 1, Page 6-69: In Section 6.2.5.3, it is concluded that the tube outside diameter and the tubesheet tube bore inside diameter always maintain contact in the predicted range of tubesheet displacements.
However, for tubes with through-wall cracks at the H* distance, there may be little or no net pressure acting on the tube for some distance above H*. In Tables 6-18 and 6-19, the fourth increment in the step that occurs two steps prior to the last step suggests that there may be no contact between the tube and tubesheet, over a portion of the circumference, for a distance above H*. Is the conclusion in 6.2.5.3 valid for the entire H* distance, given the possibility that the tubes may contain through-wall cracks at that location?
The following response to RAI#4 was included in Reference
: 11. The same response is included here to complete the record of information provided in regard to RAI#4 of References 5, 6 and 7. Response:
The conclusions reached in Section 6.2.5.3 of WCAP-17071-P are valid for the entire H* distance because of the following considerations:
: 1. The primary source of contact pressure between the tube and the tubesheet is differential thermal expansion between the tubes and the tubesheet.
The analysis in Section 6.2.5.3 specifically excludes the effect of thermal expansion of the tube from the analysis.
The tubesheet is assumed to deform due to the combination of pressure and thermal loads which produces the tube bore ovalization and leads to the displacements applied in this model. Only the residual effects from installation are considered for the tube in steps 1 through 5. The tube internal pressure applied in these steps only simUlates the hydraulic expansion pressure to establish the initial conditions for the following step. The conditions assumed for this study are not possible during any operating condition in the steam generator but are conservative relative to actual SG conditions. (Note: Residual contact pressure is not used in the calculation of H* values in Section 6. The residual effects of installation are included in the results of Section 6.2.5.3 so that the sensitivity of a strain hardened tube to tubesheet tube bore deformation can be studied.)
: 2. Step 5 on Tables 6-18 and 6-19 is not representative of any condition in the steam generator because it assumes that the tubesheet is at operating temperature with an applied primary-to-secondary pressure differential while the tubes remain at room temperature and are not pressurized.
That is why Steps 1 through 5 are described as "initializing" steps in the process. It is physically impossible for these conditions to occur simultaneously in the same steam generator.
42 LTR-SGMP-09-109 NP-Attachment
: 3. Because no pressure loading is applied to the tube in Step 5 of the analysis discussed insection 6.2.5, the results presented in Tables 6-18 and 6-19 are applicable regardless of whether, or not, a through-wall crack exists at the H* location.
The more representative case is Step 6 shown on Tables 6-18 and 6-19 in which tube internal pressure is included.
For that case, the potential point of zero contact pressure is at an applied displacement a factor of 5 greater than for Step 5, and far in excess of what is reasonably predicted for the actual tubesheet deformation.
The factor of 5 difference in required displacement to cause the contact pressure to reduce to zero more than adequately covers the postulated potential local reduction in crevice pressure due to a circumferential separation at the location of H*. Recall also, that no thermal expansion of the tube is considered in this analysis.It is also noted that tables 6-18 and 6-19 are the results of a sensitivity study that is not intended to represent the integrated calculation for H*. The integrated H* analysis is a complex process that combines the effects of several types of loading and deformation into an integrated estimate of the tube-to-tubesheet contact pressure.
Therefore, it is not appropriate to consider a sensitivity study out of the context of the greater analysis.
The integrated analysis presented in the complete Section 6 shows that for the combined case of the thermal effects, pressure effects, and tubesheet displacement there is tube-to-tubesheet contact pressure throughout the tubesheet.
It is acknowledged that the cut end of a tube is radially less stiff than a tube that is radially loaded at a point away from the tube end, and that the presumption of a tube sever at the H*distance may represent the case of a tube end. The decreased tube-end stiffness is referred to as "compliance." In other words, a tube that is loaded at the cut end provides less resistance to the load than a tube with equal load applied a distance removed from the tube-end.
Thus, conceptually, a local "end effect" could be expected to occur due to the increased compliance of the tube-end.The calculation process for H* shown in Figure 1-1 of the H* WCAP reports and discussed in several places in the report notes that an adjustment is made to the initial prediction of H* to account for the distributed crevice pressure referenced to the predicted H* position.
Thus, the greatest crevice pressure is always located at the final value of H*. Increased tube compliance cannot result in a higher local crevice pressure than is already included in the analysis because, at the point of sever, the primary side pressure is the crevice pressure.It may be postulated that the increased tube compliance results in reduced contact pressure because the net differential pressure across the tube wall is zero. At the tube-end, the current analysis already includes a zero differential pressure due to the adjustment process fordistributed crevice pressure.
Therefore, the net reduction in contact pressure would be limited to the axial length of the local effect and would further depend on the slope of the decrease in crevice pressure.For the Model F and Model D5 SGs, the bounding value of isolation distance above the tube end is 0.6 inch based on classical solutions for the design of pressure vessels (Timoshenko).
43 L TR-SGMP-09-1 09 NP-Attachment
: 3. Because no pressure loading is applied to the tube in Step 5 of the analysis discussed in section 6.2.5, the results presented in Tables 6-18 and 6-19 are applicable regardless of whether, or not, a through-wall crack exists at the H* location.
The more representative case is Step 6 shown on Tables 6-18 and 6-19 in which tube internal pressure is included.
For that case, the potential point of zero contact pressure is at an applied displacement a factor of 5 greater than for Step 5, and far in excess of what is reasonably predicted for the actual tubesheet deformation.
The factor of 5 difference in required displacement to cause the contact pressure to reduce to zero more than adequately covers the postulated potential local reduction in crevice pressure due to a circumferential separation at the location of H*. Recall also, that no thermal expansion of the tube is considered in this analysis.
It is also noted that tables 6-18 and 6-19 are the resultsof a sensitivity study that is not intended to represent the integrated calculation for H*. The integrated H* analysis is a complex process that combines the effects of several types of loading and deformation into an integrated estimate of the tube-to-tubesheet contact pressure.
Therefore, it is not appropriate to consider a sensitivity study out of the context of the greater analysis.
The integrated analysis presented in the complete Section 6 shows that for the combined case of the thermal effects, pressure effects, and tubesheet displacement there is tube-to-tubesheet contact pressure throughout the tubesheet.
It is acknowledged that the cut end of a tube is radially less stiff than a tube that is radially loaded at a point away from the tube end, and that the presumption of a tube sever at the H* distance may represent the case of a tube end. The decreased tube-end stiffness is referred to as "compliance." In other words, a tube that is loaded at the cut end provides less resistance to the load than a tube with equal load applied a distance removed from the tube-end.
Thus, conceptually, a local "end effect" could be expected to occur due to the increased compliance of the tube-end.
The calculation process for H* shown in Figure 1-1 of the H* WeAP reports and discussed in several places in the report notes that an adjustment is made to the initial prediction of H* to account for the distributed crevice pressure referenced to the predicted H* position.
Thus, the greatest crevice pressure is always located at the final value of H*. Increased tube compliance cannot result in a higher local crevice pressure than is already included in the analysis because, at the point of sever, the primary side pressure is the crevice pressure.
It may be postulated that the increased tube compliance results in reduced contact pressure because the net differential pressure across the tube wall is zero. At the tube-end, the current analysis already includes a zero differential pressure due to the adjustment process for distributed crevice pressure.
Therefore, the net reduction in contact pressure would be limited to the axial length of the local effect and would further depend on the slope of the decrease in crevice pressure.
For the Model F and Model 05 SGs, the bounding value of isolation distance above the tube end is 0.6 inch based on classical solutions for the design of pressure vessels (Timoshenko).
43 LTR-SGMP-09-109 NP-Attachment The isolation distance is the generically applicable minimum separation distance from an applied load to a point of interest in order to safely assume that the load is in the far field relative to the point of interest.
Specific structures and load cases may have different isolation distances but the classical result by Timoshenko for a pressure vessel will conservatively bound any specific cases. For this length, the slope of the contact pressure curve would have to decrease by a factor of at least [ ]a,c,e before the value of H* is affected by more than [ ]ace inch. If the tube is conservatively modeled as a center-loaded beam on an elastic foundation compared to an end-loaded beam on an elastic foundation, the resulting worst case change in structural compliance and the resulting contact pressure slope could be a factor of up to 2. Alternatively, similar analyses for the cross sections of curved beams suggest that the change in compliance of the structure could be as high as a factor of 6. Neither case approaches the factor of [ 1",c,e required based on classical pressure vessel analysis to impact the value of H*; therefore, no additional adjustments to H* are necessary to address the potential end effects.6,0 Summary of the Response to RAI #4 A summary of the response to the original RAI# 4 and additional questions related to RAI 4 areprovided below:
: 1. No additional adjustment to the value for H* is necessary to address the potential for end effects. This is because the greatest crevice pressure is always located at the final value of H*. At the H* distance, the current analysis already includes a zero pressure differential due to the adjustment process for the distributed crevice pressure.
Therefore, the net reduction in contact pressure would be limited to the axial length of the local effect and would further depend on the slope of the decrease in crevice pressure.
It is judged that the slope of the contact pressure curve would not decrease at a rate such that the value of H*would be affected.2. Tube bore dilation is a more significant factor in determining tube-to-tubesheet contact pressure at higher temperatures and the effect of eccentricity on contact pressure is reduced at higher temperatures.
The methodology for addressing the effect of eccentricity on contact pressure discussed in Reference 6-15 and utilized in WCAP-17071-P, WCAP-17072-P, WCAP-17091-P and WCAP-17092-P reflects this fact and, therefore, it provides acceptably accurate contact pressure results at higher temperatures (i.e., for all conditions except the "colder" SLB condition).
This includes NOP, SLB (higher temperature, > 400 0 F, and FLB, where appropriate).
: 3. The results of using the fit described in Reference 6-15 match the expected trend from a best case finite element model for the NOP and SLB conditions for the Model F SGs and NOP conditions for the Model D5 SG.4. The ADs from the 3D FEA model are significantly less than the corresponding ADs from the unit cell model from the unloaded to the fully loaded condition (i.e., 44 L TR-SGMP-09-1 09 NP-Attachment The isolation distance is the generically applicable minimum separation distance from an applied load to a point of interest in order to safely assume that the load is in the far field relative to the point of interest.
Specific structures and load cases may have different isolation distances but the classical result by Timoshenko for a pressure vessel will conservatively bound any specific cases. For this length, the slope of the contact pressure curve would have to decrease by a factor of at least [ ]a.c.e before the value of H* is affected by more than [ ]a.c.e inch. If the tube is conservatively modeled as a center-loaded beam on an elastic foundation compared to an end-loaded beam on an elastic foundation, the resulting worst case change in structural compliance and the resulting contact pressure slope could be a factor of up to 2. Alternatively, similar analyses for the cross sections of curved beams suggest that the change in compliance of the structure could be as high as a factor of 6. Neither case approaches the factor of [ ]a.c.e required based on classical pressure vessel analysis to impact the value of H*; therefore, no additional adjustments to H* are necessary to address the potential end effects. 6.0 Summary of the Response to RAI #4 A summary of the response to the original RAI# 4 and additional questions related to RAI 4 are provided below: 1. No additional adjustment to the value for H* is necessary to address the potential for end effects. This is because the greatest crevice pressure is always located at the final value of H*. At the H* distance, the current analysis already includes a zero pressure differential due to the adjustment process for the distributed crevice pressure.
Therefore, the net reduction in contact pressure would be limited to the axial length of the local effect and would further depend on the slope of the decrease in crevice pressure.
It is judged that the slope of the contact pressure curve would not decrease at a rate such that the value of H* would be affected.
: 2. Tube bore dilation is a more significant factor in determining tube-to-tubesheet contact pressure at higher temperatures and the effect of eccentricity on contact pressure is reduced at higher temperatures.
The methodology for addressing the effect of eccentricity on contact pressure discussed in Reference 6-15 and utilized in WCAP-17071-P, WCAP-17072-P, WCAP-17091-P and WCAP-17092-P reflects this fact and, therefore, it provides acceptably accurate contact pressure results at higher temperatures (i.e., for all conditions except the "colder" SLB condition).
This includes NOP, SLB (higher temperature, > 400&deg;F, and FLB, where appropriate).
: 3. The results of using the fit described in Reference 6-15 match the expected trend from a best case finite element model for the NOP and SLB conditions for the Model F SGs and NOP conditions for the Model 05 SG. 4. The from the 30 FEA model are significantly less than the corresponding from the unit cell model from the unloaded to the fully loaded condition (i.e., 44 LTR-SGMP-09-109 NP-Attachment from step 0 to step 9) for both NOP and SLB conditions.
This leads to the conclusion that the unit cell model displacement results and contact pressure predictions conservatively represent the reference 3D FEA model results.5. The eccentricities from the unit cell model are generally comparable to those from the 3D FEA model. A more exact comparison is difficult based on the available data; however, it is clear that the actual range of eccentricities from the 3D FEA model was adequately addressed by the unit cell model.6. Based on items 4) and 5) which demonstrate the acceptability of the use of the unit cell model for benchmarking the 3-D FEA model, the method for calculating the reduction in contact pressure defined by the unit cell model, when adjusted for temperature effects, shows that SLB contact pressure is increased relative to normal operating conditions for the Model D5 steam generators.
: 7. It has also been shown when comparing contact pressures for NOP conditions for the unit cell to contact pressures for SLB for the unit cell for the Model F SG (higher temperature SLB conditions), that contact pressure increases during a postulated SLB.8. Given that the two structural models provide similar eccentricities, the unit cell model shows that for these eccentricities, positive contact pressure existsbetween the tubes and the tubesheet for the entire range of displacements considered.
Based on the above, it is concluded that the NOP contact pressures that define H*
in the Model F and Model D5 SG are conservative and that a more realistic model of contact pressure reduction as a function of tube bore deformation (including both dilation and eccentricity) would predict positive contact pressure around the entire circumference of the tube and an increase in tube to tubesheet contact pressure at SLB conditions compared to NOP conditions.
The conclusions reached in the response to RAI#4 apply equally for the Model 44F and Model 51IF SGs.45 L TR-SGMP-09-1 09 NP-Attachment from step 0 to step 9) for both NOP and SLB conditions.
This leads to the conclusion that the unit cell model displacement results and contact pressure predictions conservatively represent the reference 3D FEA model results. 5. The eccentricities from the unit cell model are generally comparable to those from the 3D FEA model. A more exact comparison is difficult based on the available data; however, it is clear that the actual range of eccentricities from the 3D FEA model was adequately addressed by the unit cell model. 6. Based on items 4) and 5) which demonstrate the acceptability of the use of the unit cell model for benchmarking the 3-D FEA model, the method for calculating the reduction in contact pressure defined by the unit cell model, when adjusted for temperature effects, shows that SLB contact pressure is increased relative to normal operating conditions for the Model 05 steam generators.
: 7. It has also been shown when comparing contact pressures for NOP conditions for the unit cell to contact pressures for SLB for the unit cell for the Model F SG (higher temperature SLB conditions), that contact pressure increases during a postulated SLB. 8. Given that the two structural models provide similar eccentricities, the unit cell model shows that for these eccentricities, positive contact pressure exists between the tubes and the tubesheet for the entire range of displacements considered.
Based on the above, it is concluded that the NOP contact pressures that define H* in the Model F and Model 05 SG are conservative and that a more realistic model of contact pressure reduction as a function of tube bore deformation (including both dilation and eccentricity) would predict positive contact pressure around the entire circumference of the tube and an increase in tube to tubesheet contact pressure at SLB conditions compared to NOP conditions.
The conclusions reached in the response to RAI#4 apply equally for the Model 44F and Model 51F SGs. 45 Vogtle Electric Generating Plant Units 1 and 2 Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specification (TS)Sections 5.5.9, "Steam Generator (SG) Program" and TS 5.6.10, "Steam Generator Tube Inspection Report" for Permanent Alternate Repair Criteria Enclosure 3 Westinghouse Electric Company LLC, CAW-09-2661,"Application for Withholding Proprietary Information from Public Disclosure" Vogtle Electric Generating Plant Units 1 and 2 Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specification (TS) Sections 5.5.9, "Steam Generator (SG) Program" and TS 5.6.10, "Steam Generator Tube Inspection Report" for Permanent Alternate Repair Criteria Enclosure 3 Westinghouse Electric Company LLC, CAW-09-2661, "Application for Withholding Proprietary Information from Public Disclosure"
* Westinghouse U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001 Westinghouse Electric Company Nuclear Services P.O. Box 355 Pittsburgh, Pennsylvania 15230-0355 USA Directtel:  
(412) 374-4643 Direct fax: (412) 374-3846 e-mail: greshaja@westinghouse.com Our ref. CAW-09-2661 August 27, 2009 APPLICATION FOR WITHHOLDING PROPRIETARYINFORMATION FROM PUBLIC DISCLOSURE


==Subject:==
==Subject:==
LTR-SGMP-09-109 P-Attachment, "Response to NRC Request for Additional Information on H*; RAI # 4; Model F and Model D5 Steam Generators," dated August 2009 (Proprietary)The proprietary information for which withholding is being requested in the above-referenced report is further identified in Affidavit CAW-09-2661 signed by the owner of the proprietary information, Westinghouse Electric Company LLC. The affidavit, which accompanies this letter, sets forth the basis on which the information may be withheld from public disclosure by the Commission and addresses with specificity the considerations listed in paragraph (b)(4) of 10 CFR Section 2.390 of the Commission's regulations.
LTR-SGMP-09-109                         "Response to NRC Request for Additional Additional Information Information on H*; RAI # 4; Model Model F and Model Model D5 Steam Generators,"
Accordingly, this letter authorizes the utilization of the accompanying affidavit by Southern Nuclear Company.Correspondence with respect to the proprietary aspects of the application for withholding or theWestinghouse affidavit should reference this letter, CAW-09-266 1, and should be addressed to J. A. Gresham, Manager, Regulatory Compliance and Plant Licensing, Westinghouse Electric Company LLC, P.O. Box 355, Pittsburgh, Pennsylvania 15230-0355.
Generators," dated August 2009 (Proprietary)
Very truly y urs, J.A. Gresham, ManagerRegulatory Compliance and Plant Licensing Enclosures cc: G. Bacuta, (NRC OWFN 12E-1)e) Westinghouse U.S. Nuclear Regulatory Commission Document Control Desk Washington, DC 20555-0001 Westinghouse Electric Company Nuclear Services P.O. Box 355 Pittsburgh.
(Proprietary)
Pennsylvania 15230-0355 USA Directtel:  
The proprietary proprietary information information for which withholding is being requested in the above-referenced above-referenced report is further identified in Affidavit CA CAW-09-2661 W 2661 signed by the owner of the proprietary          information, proprietary information, Westinghouse Westinghouse Electric Company Company LLC. The affidavit, which accompanies accompanies this letter, sets forth the basis on which the information may be withheld from public disclosure disclosure by the Commission and addresses with specificity specificity the considerations considerations listed in paragraph paragraph (b)(4) of 10 CFR Section 2.390 of the Commission's Commission's regulations.
(412)374-4643 Directfax:  
Accordingly, Accordingly, this letter authorizes authorizes the utilization of the accompanying affidavit by Southern Southern Nuclear Company.
(412) 374-3846 e-mail: greshaja@westinghouse.com Our ref: CAW 2661 August 27, 2009 APPLICA nON FOR WITHHOLDING PROPRIETARY INFORMATION FROM PUBLIC DISCLOSURE
Correspondence with respect to the proprietary Correspondence                        proprietary aspects of the application application for withholding withholding or the Westinghouse affidavit should reference reference this letter, CAW-09-2661, CAW-09-266 1, and should be addressed addressed to J. A. Gresham, Manager, Regulatory Regulatory Compliance Compliance and Plant Licensing, Westinghouse Electric Company    Company LLC, P.O. Box 355, 355, Pittsburgh, Pennsylvania  15230-0355.
Pennsylvania 15230-0355.
Very truly y urs, J.A. Gresham, Manager J.A. Gresham, Manager Regulatory Regulatory Compliance Compliance and  and Plant Plant Licensing Licensing Enclosures cc: G. Bacuta, Bacuta, (NRC OWFN        12E-1)
OWFN 12E-l)
 
CAW-09-2661 CA W-09-2661 bcc:          Gresham(ECE A.Gresham bee: J.1.A.                    4-7A) IL (ECE4-7A)    IL R.R.Bastien,        (NiveItes,Belgium) lL(Nivelles, Bastien, IL            Belgium)
Brinkman,IL C.C.Brinkman,      lL(Westinghouse   ElectricCo.,
(WestinghouseElectric              TwinbrookParkway, 12300Twinbrook Co.,12300                          Suite330, Parkway,Suite                  MD 20852)
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RCPL      Administrative  Aide  (ECE  4-7A)    IL (letter and affidavit RCPL Administrative Aide (ECE 4-7 A) 1L (letter and affidavit only)      only)
G.G.W. Whiteman,Waltz W. Whiteman,    WaltzMill Mill H.H. O. Lagally, WaltzMill
: 0. Lagally,  Waltz  Mill C.C.D.D.Cassino,    WaltzMill Cassino,Waltz    Mill Kandra, WaltzMill J.J.T.T.Kandra,  Waltz  Mill Robinson,ECE M.Robinson, J.J.M.                ECE557A 557A
 
CAW-09-2661 CAW  2661 AFFIDAVIT COMMONWEALTH OF PENNSYLVANIA:
COMMONWEALTH                      PENNSYLVANIA:
ss ss COUNTY OF ALLEGHENY:
Before me, the undersigned undersigned authority, personally        appeared J. A. Gresham, who, being by me duly personally appeared sworn according to law, deposes and says that he is authorized to execute        execute this Affidavit on behalf of of Westinghouse Westinghouse Electric Company LLC (Westinghouse),    (Westinghouse), and that the averments averments offact of fact set forth in this Affidavit are true and correct to the best of his knowledge, knowledge, information, and belief:
I J. A. AGresham, resham, Manager Manager Regulatory Compliance Regulatory  Compliance and Plant Licensing Licensing Sworn to and subscribed before me 27hth day of August, 2009 this 27 Notary Public COMMONWEALTH COMMONWEALTH OF        OF PENNSYLVANIA PENNSYLVANIA Notailsew NoIarJaJ Seal Sha.ml L Marle, Sharon    Madde, Notary  pubi Notary Public Monroeville Bora, Allegheny County MmnMnsylei  Boro, Allsocony  CouNtyaI Cori1mIssIOA Expires My Coormmslson            Jan. 29, Boras Jan.      2011 29,2011 Member,  Pennsylvania Association Member, Pennsylvania                of NotarIes AssocIation of  Notariles
 
CAW-09-2661 CAW-09-2661 (1)
(I) I am Manager, Regulatory Regulatory Compliance Compliance and Plant Licensing, in Nuclear Nuclear Services, Westinghouse Westinghouse (Westinghouse), and as such, I have been specifically Electric Company LLC (Westinghouse),                                      specifically delegated delegated the function of reviewing the proprietary proprietary information sought to be withheld from public disclosure disclosure in connection connection with nuclear power plant licensing licensing and rule making proceedings, and am authorized to apply for its withholding on behalf of Westinghouse.
Westinghouse.
(2)
(2) 1I am making this Affidavit in conformance conformance with the provisions of 10 CFR Section 2.390 of the Commission's regulations Commission's    regulations and in conjunction                                "Application for conjunction with the Westinghouse "Application Withholding"    accompanying this Affidavit.
Withholding" accompanying (3)
(3) I have personal knowledge knowledge of the criteria and procedures procedures utilized by Westinghouse Westinghouse in designating information information as a trade secret, privileged or as confidential commercial                    information, commercial or financial information.
(4)
(4) Pursuant to the provisions of paragraph (b)(4)(b)(4) of Section Section 2.390 of the Commission's Commission's regulations, the following is furnished for consideration consideration by the Commission in determining whether whether the information information sought to be withheld from public disclosure disclosure should be withheld.
(i)      The information information sought to be withheld from public disclosure is owned and has been held in confidence confidence by Westinghouse.
(ii)    The information information is ofa of a type customarily held in confidence confidence by Westinghouse Westinghouse and not customarily customarily disclosed to the public. Westinghouse Westinghouse has a rational basis for determining determining the types of information information customarily customarily held in confidence confidence by it and, in that connection, utilizes a system to determine when and whether to hold certain certain types of information in confidence.
confidence. The application of that system and the substance substance of that system constitute Westinghouse Westinghouse policy and provide provide the rational rational basis required.
Under that system, information is held in confidence confidence if it falls in one or more of several types, the release of which might result in the loss of an existing or potential potential competitive competitive advantage, as follows:
(a)      The information reveals the distinguishing distinguishing aspects of a process process (or component, structure, tool, method, etc.)
etc.) where prevention of its use by any of of
 
CAW-09-2661 CAW    2661 Westinghouse's competitors without license from Westinghouse constitutes a Westinghouse's competitive economic economic advantage over other companies.
(b)      It consists of supporting data, including test data, relative relative to a process (or (or component, structure, tool, method, etc.), the application of which data secures compQnent,                                                                  secures a optimization or improved competitive economic advantage, e.g., by optimization          improved marketability.
marketability .
(c)    Its use by a competitor would reduce his expenditure of resources resources or improve his competitive competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.
(d)    It reveals cost or price information, information, production production capacities, budget levels, oror commercial strategies of Westinghouse, its customers or suppliers.
commercial (e)
(e)    It reveals aspects aspects of past, present, or future Westinghouse Westinghouse or customer funded development plans and programs of potential development                                        commercial value to Westinghouse.
potential commercial (f)    It contains patentable patentable ideas, for which patent protection may be desirable.
There are sound policy reasons behind the Westinghouse Westinghouse system which include the following:
(a)    The use of such information by Westinghouse Westinghouse gives Westinghouse Westinghouse a competitive competitive advantage over its competitors. It is, therefore, advantage                                therefore, withheld from disclosure disclosure to protect the Westinghouse competitive competitive position.
(b)    It is information information that is marketable marketable in many ways. The extent to which such information information is available available to competitors diminishes the Westinghouse ability to sell products products and services services involving the use of the information.
(c)     Use by our competitor would put Westinghouse Westinghouse at a competitive competitive disadvantage disadvantage by reducing his expenditure of resources resources at our expense.
expense.
 
CAW-09-2661 CA  W-09-2661 (d)
(d)                                        information pertinent Each component of proprietary information      pertinent to a particular particular competitive competitive advantage is potentially as valuable as the total competitive advantage                                          competitive advantage.
advantage. IfIf competitors acquire acquire components of proprietary proprietary information,    any one component information, anyone      component may be the key to the entire puzzle, puzzle, thereby depriving Westinghouse Westinghouse of a competitive advantage.
competitive  advantage.
(e)
(e)      Unrestricted Unrestricted disclosure disclosure would jeopardize jeopardize the position of prominence prominence of of Westinghouse in the world market, and thereby thereby give a market advantage to the competition of those countries.
(f)      The Westinghouse capacity capacity to invest corporate assets in research and development development depends depends upon the success in obtaining and maintaining maintaining a competitive advantage.
competitive (iii)
(iii)        information is being transmitted to the Commission in confidence The information                                                  confidence and, under the provisions of 10 CFR Section 2.390, it is to be received in confidence confidence by the Commission.
(iv)
(iv)  The information sought to be protected is not available in public sources or available available information has not been been previously employed in the samesame original manner or method to the best of our knowledge and belief.
belief.
(v) The proprietary proprietary information information sought to be withheld in this submittal is that which is  is appropriately marked in LTR-SGMP-09-109 LTR-SGMP-09-1 09 P-Attachment,        "Response to NRC Request P-Attachment, "Response                Request for Additional Additional Information Information on H*; RAI # 4; Model F and Model D5 Steam Generators,"
Generators,"
dated August 2009 (Proprietary), for submittal submittal to the Commission, Commission, being transmitted by Company letter and Application for Withholding Proprietary Southern Nuclear Company                                                  Proprietary Information from Public Information          Public Disclosure to the Document Control Desk. The proprietary proprietary information as submitted submitted for use by Westinghouse for Vogtle Units 1 and 2 is expected to be applicable to other licensee licensee submittals in support support of implementing an alternate repair repair criterion, called called H*, that does not require an eddy current inspection inspection and plugging of  of steam steam generator generator tubes below a certain certain distance from the top of the tubesheet.
This information information is part of that which will enable enable Westinghouse to: to:
 
CAW 2661 CAW-09-2661 (a)      Provide documentation documentation of the analyses, methods, and testing which support the implementation implementation of an alternate repair criterion, criterion, designated as H*, for a portion ofof the tubes within the tubesheet of  the.Vogtle Units 11 and 2 steam oftheVogtle                  steam generators.
generators.
(b)
(b)      Assist the customer customer in obtaining NRC approval of the Technical Specification Specification changes associated with the alternate repair repair criterion.
Further this information has substantial    commercial value as follows:
substantial commercial (a)      Westinghouse plans plans to sell the use of similar information information to its customers customers for the purposes of meeting NRC requirements requirements for licensing licensing documentation.
(b)      Westinghouse can sell support and defense of the technology to its customers in the licensing process.
Public disclosure of this proprietary proprietary information information is likely to cause cause substantial harm to the competitive competitive position of Westinghouse because it would enhance  enhance the ability of ability of competitors to provide competitors      provide similar calculation, calculation, evaluation evaluation and licensing defense services for commercial power reactors commercial            reactors without commensurate commensurate expenses. Also, public disclosure of    of the information would enable others to use the information to meet NRC requirements for documentation without purchasing licensing documentation              purchasing the right to use the information.
The development of the technology described in part by the information is the result of      of applying the results of many years of experience experience in an intensive Westinghouse effort and the expenditure expenditure of a considerable considerable sum of money.
In order for competitors      Westinghouse to duplicate competitors of Westinghouse        duplicate this information, similar technical programs would have to be performed performed and a significant manpower effort, having the requisite requisite talent and experience, experience, would have to be expended.
Further the deponent deponent sayeth not.
 
CAW-09-2661 CA  W-09-2661 PROPRIETARY INFORMATION PROPRIETARY          INFORMATION NOTICE Transmitted Transmitted herewith are proprietary proprietary and/or non-proprietary non-proprietary versions versions of documents furnished to the NRC in connection with requests for generic and/or plant-specific plant-specific review and approval.
In order to conform conform to the requirements requirements of 10 CFR 2.390 ofthe  of the Commission's regulations concerning the protection of proprietary concerning                      proprietary information so submitted to the NRC, the information information which is proprietary proprietary in the proprietary proprietary versions is contained within brackets, and where the proprietary information information has been deleted in the non-proprietary non-proprietary versions, only the brackets brackets remain remain (the information information that was contained within the brackets brackets in the proprietary versions having been deleted). The justification justification for claiming the information so designated as proprietary proprietary is indicated in both versions by means of      lower case letters (a) through (f) located as a superscript oflower                                                superscript immediately following the brackets enclosing each item of information being identified  identified as proprietary proprietary or in the margin opposite such information. These lower case letters refer to the types of information information Westinghouse customarily holds in confidence confidence identified identified in Sections Sections (4)(ii)(a) through (4)(ii)(f) of the affidavit  accompanying this transmittal pursuant to 10 CFR 2.390(b)(1).
affidavit accompanying                                              2.390(b)(1).
COPYRIGHT COPYRIGHT NOTICE The reports transmitted herewith each bear a Westinghouse Westinghouse copyright copyright notice. The NRC is permitted to make the number of copies of the information information contained in these reports which are contained necessary for its internal internal use  in connection connection  with  generic and plant-specific plant-specific reviews and approvals as well as the issuance, denial, amendment, transfer, renewal, modification, modification, suspension, revocation, revocation,  or  violation  of a license, permit, pennit,  order, or  regulation regulation subject subject to the requirements requirements of 1010 CFR 2.390 regarding      restrictions regarding restrictions    on public  disclosure to the extent such information infonnation has been identified as proprietary proprietary by Westinghouse, copyright copyright protection notwithstanding. With respect to the non-proprietary the  non-proprietary versions versions of these reports, the NRC is permitted to make the number of copies beyond those necessary necessary for its internal use which are necessary necessary in order order to have one copy available for public viewing in the appropriate docket files in the public document document room in Washington, Washington, DC and in local public document rooms as may be required by NRC regulations if the number of copies submitted is insufficient insufficient for this purpose. Copies made by the NRC must include the copyright copyright notice in all instances and the proprietary proprietary notice if the original was identified identified as proprietary.
proprietary.


==Subject:==
CAW-09-2661 CA W-09-2661 Southern Southern Nuclear Nuclear Company Letter for Transmittal to the NRC paragraphs should be included in your letter to the NRC:
LTR-SGMP-09-109 P-Attachment, "Response to NRC Request for Additional Information on H*; RAI # 4; Model F and Model D5 Steam Generators," dated August 2009 (Proprietary)
The following paragraphs Enclosed Enclosed are:
The proprietary information for which withholding is being requested in the above-referenced report is further identified in Affidavit CA W 2661 signed by the owner of the proprietary information, Westinghouse Electric Company LLC. The affidavit, which accompanies this letter, sets forth the basis on which the information may be withheld from public disclosure by the Commission and addresses with specificity the considerations listed in paragraph (b)(4) of 10 CFR Section 2.390 of the Commission's regulations.
of LTR-SGMP-09-109
Accordingly, this letter authorizes the utilization of the accompanying affidavit by Southern Nuclear Company. Correspondence with respect to the proprietary aspects of the application for withholding or the Westinghouse affidavit should reference this letter, CAW-09-2661, and should be addressed to J. A. Gresham, Manager, Regulatory Compliance and Plant Licensing, Westinghouse Electric Company LLC, P.O. Box 355, Pittsburgh, Pennsylvania 15230-0355.
: 1. 11 copy ofLTR-SGMP-09-1
J.A. Gresham, Manager Regulatory Compliance and Plant Licensing Enclosures cc: G. Bacuta, (NRC OWFN 12E-l)
: 1.                                09 P-Attachment,   "Response to NRC Request for Additional P-Attachment, "Response Information on H*; RAI # 4; Model F and Model D5 Information                                                      Generators," dated August 2009 05 Steam Generators,"
CAW-09-2661 bcc: J. A. Gresham (ECE 4-7A) IL R. Bastien, IL (Nivelles, Belgium)C. Brinkman, IL (Westinghouse Electric Co., 12300 Twinbrook Parkway, Suite 330, Rockville, MD 20852)RCPL Administrative Aide (ECE 4-7A) IL (letter and affidavit only)G. W. Whiteman, Waltz Mill H. 0. Lagally, Waltz Mill C. D. Cassino, Waltz Mill J. T. Kandra, Waltz Mill J. M. Robinson, ECE 557A CA W 2661 bee: 1. A. Gresham (ECE 4-7A) IL R. Bastien, lL (NiveItes, Belgium) C. Brinkman, lL (Westinghouse Electric Co., 12300 Twinbrook Parkway, Suite 330, Rockville, MD 20852) RCPL Administrative Aide (ECE 4-7 A) 1 L (letter and affidavit only) G. W. Whiteman, Waltz Mill H. O. Lagally, Waltz Mill C. D. Cassino, Waltz Mill J. T. Kandra, Waltz Mill J. M. Robinson, ECE 557A CAW-09-2661 AFFIDAVIT COMMONWEALTH OF PENNSYLVANIA:
(proprietary).
ss COUNTY OF ALLEGHENY:
(proprietary).
Before me, the undersigned authority, personally appeared J. A. Gresham, who, being by me duly sworn according to law, deposes and says that he is authorized to execute this Affidavit on behalf of Westinghouse Electric Company LLC (Westinghouse), and that the averments of fact set forth in this Affidavit are true and correct to the best of his knowledge, information, and belief: A resham, Manager Regulatory Compliance and Plant Licensing Sworn to and subscribed before me this 27h day of August, 2009 Notary Public COMMONWEALTH OF PENNSYLVANIA Notailsew Sha.ml L Marle, Notary pubi MmnMnsylei Boro, Allsocony CouNtyaI My Coormmslson Boras Jan. 29,2011 Member, Pennsylvania Association of Notariles CAW 2661 AFFIDAVIT COMMONWEALTH OF PENNSYLVANIA:
: 2. 11 copy of LTR-SGMP-09-109 LTR-SGMP-09-1 09 NP-Attachment,         "Response to NRC Request for Additional NP-Attachment, "Response Model F and Model 05 Information on H*; RAI # 4; Model Information                                                      Generators," dated August 2009 D5 Steam Generators,"
ss COUNTY OF ALLEGHENY:
(non-proprietary).
Before me, the undersigned authority, personally appeared J. A. Gresham, who, being by me duly sworn according to law, deposes and says that he is authorized to execute this Affidavit on behalf of Westinghouse Electric Company LLC (Westinghouse), and that the averments offact set forth in this Affidavit are true and correct to the best of his knowledge, information, and belief: Sworn to and subscribed before me this 27 th day of August, 2009 Notary Public COMMONWEALTH OF PENNSYLVANIA NoIarJaJ Seal Sharon L Madde, Notary Public Monroeville Bora, Allegheny County My Cori1mIssIOA Expires Jan. 29, 2011 Member, Pennsylvania AssocIation of NotarIes IJ. A. Gresham, Manager Regulatory Compliance and Plant Licensing CAW-09-2661 (1) I am Manager, Regulatory Compliance and Plant Licensing, in Nuclear Services, WestinghouseElectric Company LLC (Westinghouse), and as such, I have been specifically delegated the function of reviewing the proprietary information sought to be withheld from public disclosure in connection with nuclear power plant licensing and rule making proceedings, and am authorized to apply for its withholding on behalf of Westinghouse.
(non-proprietary).
(2) 1 am making this Affidavit in conformance with the provisions of 10 CFR Section 2.390 of the Commission's regulations and in conjunction with the Westinghouse "Application for Withholding" accompanying this Affidavit.
CAW-09-2661 with accompanying authorization letter CAW-09-2661 Also enclosed is Westinghouse authorization                                   accompanying affidavit, Information Notice, and Copyright Notice.
(3) I have personal knowledge of the criteria and procedures utilized by Westinghouse in designating information as a trade secret, privileged or as confidential commercial or financial information, (4) Pursuant to the provisions of paragraph (b)(4) of Section 2.390 of the Commission's regulations, the following is furnished for consideration by the Commission in determining whether the information sought to be withheld from public disclosure should be withheld.(i) The information sought to be withheld from public disclosure is owned and has been held in confidence by Westinghouse.(ii) The information is of a type customarily held in confidence by Westinghouse and not customarily disclosed to the public. Westinghouse has a rational basis for determining the types of information customarily held in confidence by it and, in that connection, utilizes a system to determine when and whether to hold certain types of information in confidence.
Proprietary Information As Item I1 contains information     proprietary to Westinghouse Electric Company information proprietary                              Company LLC, it is supported by an affidavit signed by Westinghouse, the owner of the information. The affidavitaffidavit disclosure by the sets forth the basis on which the information may be withheld from public disclosure Commission and addresses with specificity           considerations listed in paragraph (b)(4) of specificity the considerations                            of Section 2.390 of    the Commission's ofthe Commission's regulations.
The application of that system and the substance of that system constituteWestinghouse policy and provide the rational basis required.Under that system, information is held in confidence if it falls in one or more of several types, the release of which might result in the loss of an existing or potential competitive advantage, as follows: (a) The information reveals the distinguishing aspects of a process (or component, structure, tool, method, etc.) where prevention of its use by any of CAW 2661 (I) I am Manager, Regulatory Compliance and Plant Licensing, in Nuclear Services, Westinghouse Electric Company LLC (Westinghouse), and as such, I have been specifically delegated the function of reviewing the proprietary information sought to be withheld from public disclosure in connection with nuclear power plant licensing and rule making proceedings, and am authorized to apply for its withholding on behalf of Westinghouse.
information which is proprietary Accordingly, it is respectfully requested that the information                           to proprietary to disclosure in accordance Westinghouse be withheld from public disclosure Westinghouse                                              accordance with 10 CFR Section 2.390 of of Commission's regulations.
(2) I am making this Affidavit in conformance with the provisions of 10 CFR Section 2.390 of the Commission's regulations and in conjunction with the Westinghouse "Application for Withholding" accompanying this Affidavit.
the Commission's     regulations.
(3) I have personal knowledge of the criteria and procedures utilized by Westinghouse in designating information as a trade secret, privileged or as confidential commercial or financial information.
Correspondence with respect to the copyright Correspondence                                                    aspects of the items listed above or copyright or proprietary aspects Westinghouse affidavit should reference CAW-09-2661 the supporting Westinghouse                                                                  addressed CAW-09-2661 and should be addressed Gresham, Manager, to J. A. Gresham,   Manager, Regulatory     Compliance and Plant Licensing, Westinghouse Regulatory Compliance                                          Electric Westinghouse Electric Company LLC, P.O. Box 355,    355, Pittsburgh, Pennsylvania 15230-0355.
(4) Pursuant to the provisions of paragraph (b)(4) of Section 2.390 of the Commission's regulations, the following is furnished for consideration by the Commission in determining whether the information sought to be withheld from public disclosure should be withheld. (i) The information sought to be withheld from public disclosure is owned and has been held in confidence by Westinghouse. (ii) The information is ofa type customarily held in confidence by Westinghouse and not customarily disclosed to the public. Westinghouse has a rational basis for determining the types of information customarily held in confidence by it and, in that connection, utilizes a system to determine when and whether to hold certain types of information in confidence.
Pittsburgh, Pennsylvania  15230-0355.
The application of that system and the substance of that system constitute Westinghouse policy and provide the rational basis required.
                                                                                                        !i}}
Under that system, information is held in confidence if it falls in one or more of several types, the release of which might result in the loss of an existing or potential competitive advantage, as follows: (a) The information reveals the distinguishing aspects of a process (or component, structure, tool, method, etc.) where prevention of its use by any of CAW-09-2661 Westinghouse's competitors without license from Westinghouse constitutes a competitive economic advantage over other companies.(b) It consists of supporting data, including test data, relative to a process (orcomponent, structure, tool, method, etc.), the application of which data secures acompetitive economic advantage, e.g., by optimization or improved marketability.(c) Its use by a competitor would reduce his expenditure of resources or improve hiscompetitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.(d) It reveals cost or price information, production capacities, budget levels, or commercial strategies of Westinghouse, its customers or suppliers.(e) It reveals aspects of past, present, or future Westinghouse or customer fundeddevelopment plans and programs of potential commercial value to Westinghouse.(f) It contains patentable ideas, for which patent protection may be desirable.
There are sound policy reasons behind the Westinghouse system which include the following: (a) The use of such information by Westinghouse gives Westinghouse a competitive advantage over its competitors.
It is, therefore, withheld from disclosure to protect the Westinghouse competitive position.(b) It is information that is marketable in many ways. The extent to which such information is available to competitors diminishes the Westinghouse ability to sell products and services involving the use of the information.(c) Use by our competitor would put Westinghouse at a competitive disadvantage by reducing his expenditure of resources at our expense.CAW 2661 Westinghouse's competitors without license from Westinghouse constitutes a competitive economic advantage over other companies. (b) It consists of supporting data, including test data, relative to a process (or compQnent, structure, tool, method, etc.), the application of which data secures a competitive economic advantage, e.g., by optimization or improved marketability . (c) Its use by a competitor would reduce his expenditure of resources or improve his competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product. (d) It reveals cost or price information, production capacities, budget levels, or commercial strategies of Westinghouse, its customers or suppliers. (e) It reveals aspects of past, present, or future Westinghouse or customer funded development plans and programs of potential commercial value to Westinghouse. (f) It contains patentable ideas, for which patent protection may be desirable.
There are sound policy reasons behind the Westinghouse system which include the following: (a) The use of such information by Westinghouse gives Westinghouse a competitive advantage over its competitors.
It is, therefore, withheld from disclosure to protect the Westinghouse competitive position. (b) It is information that is marketable in many ways. The extent to which such information is available to competitors diminishes the Westinghouse ability to sell products and services involving the use of the information. (c) Use by our competitor would put Westinghouse at a competitive disadvantage by reducing his expenditure of resources at our expense.
CAW-09-2661 (d) Each component of proprietary information pertinent to a particular competitive advantage is potentially as valuable as the total competitive advantage.
If competitors acquire components of proprietary information, any one component may be the key to the entire puzzle, thereby depriving Westinghouse of a competitive advantage.(e) Unrestricted disclosure would jeopardize the position of prominence of Westinghouse in the world market, and thereby give a market advantage to the competition of those countries.(f) The Westinghouse capacity to invest corporate assets in research and development depends upon the success in obtaining and maintaining a competitive advantage.(iii) The information is being transmitted to the Commission in confidence and, under the provisions of 10 CFR Section 2.390, it is to be received in confidence by the Commission.(iv) The information sought to be protected is not available in public sources or available information has not been previously employed in the same original manner or method tothe best of our knowledge and belief.(v) The proprietary information sought to be withheld in this submittal is that which is appropriately marked in LTR-SGMP-09-109 P-Attachment, "Response to NRC Request for Additional Information on H*; RAI # 4; Model F and Model D5 Steam Generators," dated August 2009 (Proprietary), for submittal to the Commission, being transmitted by Southern Nuclear Company letter and Application for Withholding Proprietary Information from Public Disclosure to the Document Control Desk.
The proprietary information as submitted for use by Westinghouse for Vogtle Units 1 and 2 is expected to be applicable to other licensee submittals in support of implementing an alternate repair criterion, called H*, that does not require an eddy current inspection and plugging of steam generator tubes below a certain distance from the top of the tubesheet.
This information is part of that which will enable Westinghouse to: CA W-09-2661 (d) Each component of proprietary information pertinent to a particular competitive advantage is potentially as valuable as the total competitive advantage.
If competitors acquire components of proprietary information, anyone component may be the key to the entire puzzle, thereby depriving Westinghouse of a competitive advantage. (e) Unrestricted disclosure would jeopardize the position of prominence of Westinghouse in the world market, and thereby give a market advantage to the competition of those countries. (f) The Westinghouse capacity to invest corporate assets in research and development depends upon the success in obtaining and maintaining a competitive advantage. (iii) The information is being transmitted to the Commission in confidence and, under the provisions of 10 CFR Section 2.390, it is to be received in confidence by the Commission. (iv) The information sought to be protected is not available in public sources or available information has not been previously employed in the same original manner or method to the best of our knowledge and belief. (v) The proprietary information sought to be withheld in this submittal is that which is appropriately marked in LTR-SGMP-09-1 09 P-Attachment, "Response to NRC Request for Additional Information on H*; RAI # 4; Model F and Model D5 Steam Generators," dated August 2009 (Proprietary), for submittal to the Commission, being transmitted by Southern Nuclear Company letter and Application for Withholding Proprietary Information from Public Disclosure to the Document Control Desk. The proprietary information as submitted for use by Westinghouse for Vogtle Units 1 and 2 is expected to be applicable to other licensee submittals in support of implementing an alternate repair criterion, called H*, that does not require an eddy current inspection and plugging of steam generator tubes below a certain distance from the top of the tubesheet.
This information is part of that which will enable Westinghouse to:
CAW-09-2661 (a) Provide documentation of the analyses, methods, and testing which support the implementation of an alternate repair criterion, designated as H*, for a portion ofthe tubes within the tubesheet of the.Vogtle Units 1 and 2 steam generators.(b) Assist the customer in obtaining NRC approval of the Technical Specification changes associated with the alternate repair criterion.
Further this information has substantial commercial value as follows: (a) Westinghouse plans to sell the use of similar information to its customers for the purposes of meeting NRC requirements for licensing documentation.(b) Westinghouse can sell support and defense of the technology to its customers in the licensing process.Public disclosure of this proprietary information is likely to cause substantial harm to the competitive position of Westinghouse because it would enhance the ability of competitors to provide similar calculation, evaluation and licensing defense services for commercial power reactors without commensurate expenses.
Also, public disclosure of the information would enable others to use the information to meet NRC requirements forlicensing documentation without purchasing the right to use the information.
The development of the technology described in part by the information is the result of applying the results of many years of experience in an intensive Westinghouse effort and the expenditure of a considerable sum of money.In order for competitors of Westinghouse to duplicate this information, similar technical programs would have to be performed and a significant manpower effort, having the requisite talent and experience, would have to be expended.Further the deponent sayeth not.CAW 2661 (a) Provide documentation of the analyses, methods, and testing which support the implementation of an alternate repair criterion, designated as H*, for a portion of the tubes within the tubesheet oftheVogtle Units 1 and 2 steam generators. (b) Assist the customer in obtaining NRC approval of the Technical Specification changes associated with the alternate repair criterion.
Further this information has substantial commercial value as follows: (a) Westinghouse plans to sell the use of similar information to its customers for the purposes of meeting NRC requirements for licensing documentation. (b) Westinghouse can sell support and defense of the technology to its customers in the licensing process. Public disclosure of this proprietary information is likely to cause substantial harm to the competitive position of Westinghouse because it would enhance the ability of competitors to provide similar calculation, evaluation and licensing defense services for commercial power reactors without commensurate expenses.
Also, public disclosure of the information would enable others to use the information to meet NRC requirements for licensing documentation without purchasing the right to use the information.
The development of the technology described in part by the information is the result of applying the results of many years of experience in an intensive Westinghouse effort and the expenditure of a considerable sum of money. In order for competitors of Westinghouse to duplicate this information, similar technical programs would have to be performed and a significant manpower effort, having the requisite talent and experience, would have to be expended.
Further the deponent sayeth not.
CAW-09-2661 PROPRIETARY INFORMATION NOTICE Transmitted herewith are proprietary and/or non-proprietary versions of documents furnished to the NRC in connection with requests for generic and/or plant-specific review and approval.In order to conform to the requirements of 10 CFR 2.390 of the Commission's regulations concerning the protection of proprietary information so submitted to the NRC, the information which is proprietary in the proprietary versions is contained within brackets, and where the proprietary information has been deleted in the non-proprietary versions, only the brackets remain(the information that was contained within the brackets in the proprietary versions having beendeleted). The justification for claiming the information so designated as proprietary is indicated in both versions by means of lower case letters (a) through (f) located as a superscript immediately following the brackets enclosing each item of information being identified as proprietary or in the margin opposite such information.
These lower case letters refer to the types of information Westinghouse customarily holds in confidence identified in Sections (4)(ii)(a) through (4)(ii)(f) of the affidavit accompanying this transmittal pursuant to 10 CFR 2.390(b)(1).
COPYRIGHT NOTICE The reports transmitted herewith each bear a Westinghouse copyright notice. The NRC is permitted to make the number of copies of the information contained in these reports which are necessary for its internal use in connection with generic and plant-specific reviews and approvals as well as the issuance, denial, amendment, transfer, renewal, modification, suspension, revocation, or violation of a license, permit, order, or regulation subject to the requirements of 10 CFR 2.390 regarding restrictions on public disclosure to the extent such information has been identified as proprietary by Westinghouse, copyright protection notwithstanding.
With respect to the non-proprietary versions of these reports, the NRC is permitted to make the number of copiesbeyond those necessary for its internal use which are necessary in order to have one copyavailable for public viewing in the appropriate docket files in the public document room in Washington, DC and in local public document rooms as may be required by NRC regulations if the number of copies submitted is insufficient for this purpose. Copies made by the NRC must include the copyright notice in all instances and the proprietary notice if the original was identified as proprietary.
CA W-09-2661 PROPRIETARY INFORMATION NOTICE Transmitted herewith are proprietary and/or non-proprietary versions of documents furnished to the NRC in connection with requests for generic and/or plant-specific review and approval.
In order to conform to the requirements of 10 CFR 2.390 ofthe Commission's regulations concerning the protection of proprietary information so submitted to the NRC, the information which is proprietary in the proprietary versions is contained within brackets, and where the proprietary information has been deleted in the non-proprietary versions, only the brackets remain (the information that was contained within the brackets in the proprietary versions having been deleted).
The justification for claiming the information so designated as proprietary is indicated in both versions by means oflower case letters (a) through (f) located as a superscript immediately following the brackets enclosing each item of information being identified as proprietary or in the margin opposite such information.
These lower case letters refer to the types of information Westinghouse customarily holds in confidence identified in Sections (4)(ii)(a) through (4)(ii)(f) of the affidavit accompanying this transmittal pursuant to 10 CFR 2.390(b)(1).
COPYRIGHT NOTICE The reports transmitted herewith each bear a Westinghouse copyright notice. The NRC is permitted to make the number of copies of the information contained in these reports which are necessary for its internal use in connection with generic and plant-specific reviews and approvals as well as the issuance, denial, amendment, transfer, renewal, modification, suspension, revocation, or violation of a license, pennit, order, or regulation subject to the requirements of 10 CFR 2.390 regarding restrictions on public disclosure to the extent such infonnation has been identified as proprietary by Westinghouse, copyright protection notwithstanding.
With respect to the non-proprietary versions of these reports, the NRC is permitted to make the number of copies beyond those necessary for its internal use which are necessary in order to have one copy available for public viewing in the appropriate docket files in the public document room in Washington, DC and in local public document rooms as may be required by NRC regulations if the number of copies submitted is insufficient for this purpose. Copies made by the NRC must include the copyright notice in all instances and the proprietary notice if the original was identified as proprietary.
CAW-09-2661 Southern Nuclear Company Letter for Transmittal to the NRCThe following paragraphs should be included in your letter to the NRC: Enclosed are:1. 1 copy of LTR-SGMP-09-109 P-Attachment, "Response to NRC Request for Additional Information on H*; RAI # 4; Model F and Model D5 Steam Generators," dated August 2009 (proprietary).
: 2. 1 copy of LTR-SGMP-09-109 NP-Attachment, "Response to NRC Request for Additional Information on H*; RAI # 4; Model F and Model D5 Steam Generators," dated August 2009 (non-proprietary).
Also enclosed is Westinghouse authorization letter CAW-09-2661 with accompanying affidavit, Proprietary Information Notice, and Copyright Notice.
As Item 1 contains information proprietary to Westinghouse Electric Company LLC, it is supported by an affidavit signed by Westinghouse, the owner of the information.
The affidavit sets forth the basis on which the information may be withheld from public disclosure by the Commission and addresses with specificity the considerations listed in paragraph (b)(4) of Section 2.390 of the Commission's regulations.
Accordingly, it is respectfully requested that the information which is proprietary to Westinghouse be withheld from public disclosure in accordance with 10 CFR Section 2.390 of the Commission's regulations.
Correspondence with respect to the copyright or proprietary aspects of the items listed above or the supporting Westinghouse affidavit should reference CAW-09-2661 and should be addressed to J. A. Gresham, Manager, Regulatory Compliance and Plant Licensing, Westinghouse Electric Company LLC, P.O. Box 355, Pittsburgh, Pennsylvania 15230-0355.
!i Southern Nuclear Company Letter for Transmittal to the NRC The following paragraphs should be included in your letter to the NRC: Enclosed are: CA W 2661 1. 1 copy ofLTR-SGMP-09-1 09 P-Attachment, "Response to NRC Request for Additional Information on H*; RAI # 4; Model F and Model 05 Steam Generators," dated August 2009 (proprietary).
: 2. 1 copy of LTR-SGMP-09-1 09 NP-Attachment, "Response to NRC Request for Additional Information on H*; RAI # 4; Model F and Model 05 Steam Generators," dated August 2009 (non-proprietary).
Also enclosed is Westinghouse authorization letter CA W-09-2661 with accompanying affidavit, Proprietary Information Notice, and Copyright Notice. As Item I contains information proprietary to Westinghouse Electric Company LLC, it is supported by an affidavit signed by Westinghouse, the owner of the information.
The affidavit sets forth the basis on which the information may be withheld from public disclosure by the Commission and addresses with specificity the considerations listed in paragraph (b)(4) of Section 2.390 ofthe Commission's regulations.
Accordingly, it is respectfully requested that the information which is proprietary to Westinghouse be withheld from public disclosure in accordance with 10 CFR Section 2.390 of the Commission's regulations.
Correspondence with respect to the copyright or proprietary aspects of the items listed above or the supporting Westinghouse affidavit should reference CAW-09-2661 and should be addressed to J. A. Gresham, Manager, Regulatory Compliance and Plant Licensing, Westinghouse Electric Company LLC, P.O. Box 355, Pittsburgh, Pennsylvania 15230-0355.}}

Latest revision as of 00:04, 22 March 2020

Enclosure 2 and 3 to NL-09-1375 - Response to Request for Additional Information Related to License Amendment Request to Revise Technical Specification (TS) Sections 5.5.9 and TS 5.6.10
ML092470144
Person / Time
Site: Vogtle  Southern Nuclear icon.png
Issue date: 08/25/2009
From:
Westinghouse
To:
Office of Nuclear Reactor Regulation
References
LTR-SGMP-09-109 NP, NL-09-1375
Download: ML092470144 (55)


Text

WESTINGHOUSE WESTINGHOUSE NON-PROPRIETARY NON-PROPRIETARY CLASS 3 LTR-SGMP-09-109 L TR-SGMP-09-1 09 NP-Attachment NP-Attachment Westinghouse Electric Company Westinqhouse Company, Response to NRC Request Request for Additional Additional Information on H*; RAI #4; Model F and Model Model 05 D5 Steam Generators Generators August 25, 2009 Westinghouse Westinghouse Electric Electric Company LLC Company LLC P.O. Box 158 158 Madison, PA 15663 Madison, 15663

© 2009 Westinghouse Westinghouse Electric Company LLC LLC All All Rights Reserved Rights Reserved

  • Electronicallyapproved records are authenticatedin the Electronic Document Management System

'Electronically approved records are authenticated in the Electronic Document Management System 1

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment Response to NRC Request Request for Additional Additional Information on H*; RAI #4; Model Model 05 Model F and Model D5 Steam Generators Generators

References:

References:

NL-09-0547, Vogtle Electric Generating

1. NL-o.9-o.547, Generating Plant License License Amendment Request to Revise Revise Specification(TS) Sections 5.5.9, "Steam Generator Technical Specification(TS) Generator (SG)

(SG) Program" and TS TS 5.6.10, 5.6.10., "Steam Generator Generator Tube Inspection Report Inspection Report for Permanent Alternate Alternate Repair Criteria,"

Southern Company, May 19, 20.0.9. 2009.

2. RS-09-071, RS-o.9-071, "License Amendment Amendment Request Request to Revise Revise Technical Specifications Specifications (TS) for for Permanent Alternate Permanent Alternate Repair Criteria," Exelon Nuclear, June 24, 2009. 20.0.9.

CP-200900748, Log # TXX-o.9o.75,

3. CP-2o.o.9o.o.748, TXX-09075, "Comanche Peak Steam Steam Electric Station (CPSES)

Docket 50-445 and 50.-446, Docket Nos. 50.-445 50-446, License Amendment Request 09-007, Model D5 0.9-0.0.7, Model 05 Steam Generator Generator Alternate Repair Criteria," Luminant, June June 8, 20.0.9.

2009.

4. SBK-L-o.9118, SBK-L-09118, "Seabrook Station: License Amendment Amendment Request 09-03; 0.9-0.3; Revision to Specification 6.7.6.k, "Steam Generator Technical Specification Generator (SG) Program," for PermanentPermanent Alternate Alternate Repair Criteria (H*),"

Repair (H*)," May 28, 2009.

20.0.9.

5. Vogtle Electric Generating Generating Plant, Units 1 and 2, Request Request for Additional Information Information Regarding Steam Generator Regarding Generator Program (TAC Nos. ME1339 and ME134o.)," ME1340)," United States United States Nuclear Nuclear Regulatory Commission, July 1 Regulatory Commission, 10, 0., 2009.

20.0.9.

6. Braidwood Braidwood Station, Units 1 and 2, and Byron Station, Unit Nos. 1 and 2 - Request Request for Additional Information Information Related Related to Steam Generator Generator Permanent Permanent Alternate Alternate Repair Criteria Criteria (TAC Nos. ME1613, ME1614, ME1615, and ME1616)," United States Nuclear Regulatory Commission, JulyJuly 20, 2009.

20.,20.0.9.

7. Comanche Peak Peak Steam Electric Station, Units 1 and 2 - RequestRequest for Additional Information Information Regarding the Permanent Regarding Permanent Alternate Repair Repair Criteria Criteria License License Amendment Amendment Request (TAC Nos.

ME1446 and ME1447)," United States ME1446 States Nuclear Nuclear Regulatory Commission, 23, 2009.

Commission, July 23,20.0.9.

8. WCAP-17071-P, WCAP-17o.71-P, "H*: Alternate Repair Repair Criteria for the Tubesheet Tubesheet Expansion Region in in Generators with Hydraulically Steam Generators Hydraulically Expanded Tubes (Model F)," Westinghouse Westinghouse Electric Electric LLC, April 20.0.9.

2009.

9. WCAP-17072-P, WCAP-17o.72-P, "H*: Alternate Repair Repair Criteria for the Tubesheet Tubesheet Expansion Expansion Region in in Generators with Hydraulically Steam Generators Hydraulically Expanded Tubes (Model 05),"

Tubes (Model D5)," Westinghouse Westinghouse Electric Electric 2009.

LLC, May 20.0.9.

110.

o.. "Vogtle Electric Generating Plant, Units 1 and 2, Request Electric Generating Request for Additional Information Additional Information Regarding Steam Generator Regarding Generator Program Program (TAC Nos. ME1339 and ME1340)," States ME134o.)," United States Nuclear Regulatory Regulatory Commission, Commission, August 5, 2009 5,20.0.9 2

2

LLTR-SGMP-09-109 TR-SGMP-09-1 09 NP-Attachment NP-Attachment

11. LTR-SGMP-09-100,
11. LTR-SGMP-09-1 00, "Response to NRC Request Request for Additional Information Information on H*; Model F and Model D5 Steam Steam Generators," August 2009
12. LLTR-NRC-09-26, TR-NRC-09-26, "L "LTR-SGMP-09-66 TR-SGMP-09-66 P-Attachment, P-Attachment, "White Paper: Low TemperatureTemperature Steam Line Break Contact Pressure and Local Tube Bore Deformation Contact Pressure Deformation Analysis for H* H*

Electric Company (Proprietary)," Westinghouse Electric Company LLC, May 13, 2009.

13. Seabrook
13. Seabrook Station, Unit No. 1- Request for Additional Information Regarding Steam Information Regarding Generator Program (TAC Nos. ME1386)," United States Nuclear Generator Nuclear Regulatory Regulatory Commission, August 13,2009 13, 2009 Introduction Introduction In response to formal requests for technical specification specification amendments, References 1, 2, 3 and amendments, References 4, the USNRC formally formally requested additional additional information in in References References 5, 6, 77 and 13. The The Vogtle, Seabrook, Byron/Braidwood Byron/Braidwood and Comanche Peak requests for a permanent permanent license license amendment amendment to implement implement H* H* represent the Model F and Model Model D5 steam generators for which the H*H*technical justification is provided in References References 8 and 9.

Subsequent to the initial issue of the RAI (References Subsequent (References 5, 6, 7 and 13), the NRC issued follow-up follow-up questions questions (Reference (Reference 10) 10) to questions questions numbers 4, 20 and 24 and an additional request regarding a technical specification (TS) commitment commitment for applying the leakage factors. Except Except for RAI#4, responses responses to all of the RAls,RAIs, including including the follow-up questions Reference 10, were questions in Reference were provided in Reference 11. 11. The affected affected licensees licensees provided separate separate responses in regard to the the commitment commitment for applying leakage factors.

The response to RAI#4 required explanation as discussed required additional explanation discussed with the NRC staff on August 11, 11, 2009 and was, therefore, not included in Reference Reference 11. 11. The additional questions additional questions related related to RAI#4 that were identified identified during the August 11, 11, 2009 telephone telephone conference conference werewere summarized summarized by Westinghouse and were the basis of the discussion discussion at a meeting a meeting among the the

NRC, NRC, several licensees licensees and Westinghouse Westinghouse on August 17 and 18, 18, 2009. These additional questions questions are reproduced reproduced in in the response to RAI#4, below. Specific discussion is included in in the response response to address the additional additional questions.

To summarize, summarize, this document document provides provides the response response to the initial RAI#4 as included in in References References 5, 6, 7 and 13, response response to the follow-up question question relating to RAI#4 in Reference 10 and response to the additional additional questions raised during during the conference conference call on August 11, 11, 2009.

Utilities, Utilities, other than referenced referenced in this document, have requested amendments to their licensees licensees in parallel parallel with the response to these RAI's. RAl's. The technical RAls RAIs are generic in nature because nature because the analysis methods are the same for all affected affected plants. Therefore, this response to RAI#4 is generic for all Models of SGs that are candidates candidates for application application of H*. However, this letter 3

3

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment specifically augments Reference specifically Reference 11 to complete the responses responses to NRC RAls RAIs for WCAP-17071-WCAP-1 7071-P (Model F H*)

H*) and WCAP-17072-P (Model(Model D5 H*).H*).

Vogtle Vogt/e 4. Reference 1, page page 6-69: In Section 6.2.5.3, 6.2.5.3, it is is concluded RAI that the tube outside diameter that diameter and the tubesheet tubesheet tube tube bore bore PartA Part inside diameter inside diameter always maintain maintain contact contact in the predicted predicted range range of tubesheet displacements.

displacements. However, However, for tubestubes with through-wall through-wallcracks cracks atat the H* distance, there H* distance, there may be little little or no net pressure pressureacting acting on the tube for some distancedistance above H*. In Tables H*. Tables 6-18 andand 6-19, 6-19, the fourth fourth increment increment in the step that occurs that occurs two steps prior last step suggests prior to the last suggests that there that there may be no contact contact between the tube and and tubesheet, tubesheet, over a portion of the circumference, portion circumference, for a distance distance above H*. Is the conclusion in Section 6.2.5.3 valid for the entire conclusion entire H* distance, H* distance, given the possibility possibility that that the tubes may contain contain through-wall through-wall cracks cracks at that location?

that location?

WCGS 4. Reference 1, page page 6-69: In Section 6.2.5.3,6.2.5.3, it is concluded that the tube outside diameter that diameter and the tubesheet tubesheet tube tube bore bore inside inside diameter diameter always maintain contact in the predicted maintain contact predicted range range of tubesheet displacements.

displacements. However, However, for tubes with through-wallcracks through-wall cracks atat the H* distance, there H* distance, there may be little little or no net pressure pressureacting acting on the tubetube for some distance distance above H*. Tables 6-18 and H*. In Tables and 6-19, 6-19, the fourth fourth increment increment in the step step that occurs that occurs two steps prior steps prior to the last last step suggests suggests that there that there may be no contact contact between the tube and tubesheet, tubesheet, over a portion of the circumference, portion circumference, for a distance distance above H*. H*. Is the conclusion in 6.2.5.3 valid for the entire conclusion entire H*

H* distance, distance, given the possibility possibility that that the tubes may contain contain through-wall through-wall cracks at that location?

that location?

B/B BIB 4. Reference 1, Page

4. Page 6-7: In Section 6.2.5.3, 6.2.5.3, it is concluded that the tube tube outside outside diameter diameterand and the tubesheet tubesheet tube bore bore

. inside diameteralways maintain inside diameter maintain contact contact in the predicted predicted range range of tubesheet tubesheet displacements.

displacements. However, However, for for tubes with through-wall cracks at the H*

through-wall cracks H* distance, distance, there there may be little little or no net pressure acting on the tube for some distance pressure acting above distance above H*. In Tables Tables 6-18 andand 6-19, the fourth increment increment in the step that occurs occurs two steps priorprior to the last step suggests suggests thatthat there there may be no contact contact between the tube and tubesheet, tubesheet, over a portion of the circumference, portion circumference, for a distance distance above H*. H*. Is the the conclusion valid for the entire conclusion in 6.2.5.3 valid entire H*

H* distance, distance, given the possibility that the tubes possibility that tubes may contain contain through-wall through-wall cracks that location.

at that location.

4

LLTR-SGMP-09-109 NP-Attachment TR-SGMP-09-109 NP-Attachment CPSES CPSES 4. Reference

4. Reference 1, 1, page page 6-70:

6-70: InIn Section 6.2.5.3, it is Section 6.2.5.3, is concluded that that the tube outside diameter tube outside diameter and and thethe tubesheet tubesheet tube tube bore bore inside diameter inside diameter always maintain contact maintain contact in in the predicted predicted range of tubesheet range tubesheet displacements.

displacements.However, However, for tubes tubes with with through-wall cracks at through-wall cracks at the H*H* distance, distance, there there may be little or be little no net pressure pressureacting acting on thethe tube for for some ,distance distance above above H*. In Tables H*. Tables 6-18 and and 6-19, 6-19, the fourth fourth increment incrementin in the step step that occurs that occurs two steps steps prior the last prior to the last step suggests suggests thatthat there there may be be no contact contact between the tube tube and and tubesheet, tubesheet, over over a portion of the circumference, portion circumference, for for aa distance distanceabove above H*.H*. Is the conclusion in conclusion in Section Section 6.2.5.3 validvalid for for the the entire entire H* H* distance, distance, possibility that given the possibility that the the tubes may contain contain through-wall through-wall cracks at that cracks that location?

location?

Seabrook Seabrook 4. Reference 1, 1, page 6-69: In Section 6.2.5.3, page 6-69: 6.2.5.3, it is concluded that the that the tube outside diameterand outside diameter and the tubesheet tubesheet tube tube bore bore inside diameter inside diameter always maintain contact in the predicted maintain contact predicted range of tubesheet range displacements. However, tubesheet displacements. However, for tubes tubes with through-wallcracks through-wall cracks atat the H*H* distance, distance, there there may be littlelittle or no net pressure pressureacting acting on the tube for for some distance distance above above H*. In Tables H*. Tables 6-18 and and 6-19, 6-19, the fourth fourth increment increment in in the step that occurs that occurs two steps steps prior prior to the lastlast step suggests suggests thatthat there there may be no contact contact between the tube and and tubesheet, tubesheet, over a portion circumference, for a distance portion of the circumference, distance above above H*. Is the the conclusion conclusion in in 6.2.5.3 valid for for the entire H* distance, entire H* distance, given the possibility possibility that that the tubes may containcontain through-wall through-wall cracks at that location?

location?

PartB: The additional Part additionalquestions questions relating relatingto RAI#4 as provided providedin Reference 10 are: are:

Address following following questions questions as partpart of response response to RAI#4 (VogtJe):(Vogtle):

a. Clarify
a. Clarify the nature nature of the finite element model ("slice" model versus versus axisymmetric axisymmetric SG assembly model) generate the specific information model) used to generate information in Tables 6-1, 2, 2, and and 3 (and accompanying (and accompanying graph graph entitled "Elliptical "Elliptical Hole Factors')

Factors'J of Reference 6-15. 6-15. What loads loads were applied?

applied? How was the eccentricity eccentricity produced produced in the model? (By modeling the eccentricity eccentricity as part part of of the geometry? By applying applying an axisymmetric axisymmetric pressure pressure the the inside inside of the bore?) Explain bore?) Explain why this model is not scalable scalable to lower temperatures.

temperatures. .

b. Provide Provide table showing maximum delta delta diameters diameters (total diameter distortion)

(total diameter distortion) and maximum eccentricities eccentricities (maximum diameterdiameter minus minimum diameter) diameter) from the 3 dimensional (3-D) finite element analysis dimensional (3-~) analysis for normal normal operating operating and and steam line break (SLB), for model F and D5. 05.

c. In Figure Figure 2 of the White Paper, Paper, add plot for original originalrelationship relationship between reductions in contact pressure pressure and eccentricity eccentricity as given in Reference 6-15 in the graph accompanying accompanying Table 6-3. Explain Explain why this original original relationship relationship remains conservative remains conservative 5

LTR-SGMP-09-109 LTR-SGMP-09-1 09 NP-Attachment NP-Attachment in light light of the new relationship.

relationship. Explain Explain the reasons reasons for the differences between the curves.

curves.

d. establishing whether
d. When establishing whether contact contact pressure pressure increases increases when going going from normalnormal operating operating to steam line break conditions, conditions, how can can a validvalid andand conservative conservative comparison be made if the normal comparison normal operating operating case is is based based on the originaloriginal delta delta contact contact pressure versus eccentricity pressure versus eccentricity curve and the SLB case case is based based on the new curve?

PartC:

Part C: Additional Additional Questions Questions Provided Provided in in the August 11,200911, 2009 telephone telephone conference:

conference:

a.

a. Overall Overall High High Level Question Question
1. Discuss
1. Discuss if the eccentricity eccentricity effect on contact pressure is occurring contact pressure occurring as described.

described. It is the opinion of the NRC staff that the eccentricity opinion eccentricity effect effect may not be as significant significant as being reported reported by Westinghouse.

Westinghouse.

Other Kev

b. Other Key Questions Questions
1. The eccentricities
1. eccentricities included Table RAI included in Table RA14-44-4 appear appearlarger than antiCipated.

larger than anticipated. Need to confirm that that positive positive contact pressure exists around contact pressure aroundthe entire circumference of the tube entire circumference and state state this this clearly clearly inin the response.

response.

2. The difference between initial initialand and final eccentricity included in Table RA14-2 eccentricity included RAI4-2 needs to be be explained.

explained. In particular, particular, the exclusive use of the relationship relationship between initial eccentricity initial eccentricity and scale scale factor factor inin calculating calculatingcontact contact pressure needs to be justified.

pressure needs justified.

3. The basis basis for applying the correlation correlation for scale scale factor factor outside an "eccentricity" "eccentricity"rangerange of of between 1IE-3E-3 to 1E-4 1E-4 inch in the calculation of contact calculation contact pressure pressure needs to be further further explained.

explained. Values for for displacements displacements included included in Table 6-18 (of WCAP-17071)

WCAP-17071) suggest suggest that contact pressure that contact pressure may be lost at displacement ranging displacement ranging between 1E-3 1E-3 in to 1E-4 inch.

1E-4 inch.

4. Provide Provide the calculation calculationbasis basis for the upper upper and lower curves provided in Figure provided Figure RAI 4-2
5. Resolve the apparent apparentinconsistency inconsistency between Item 4 on page page 25 and the statement Figure RA14-1 below Figure RAI4-1 regarding regarding how the model in Figure Figure RAI4-1 RA14-1 is loaded.

loaded.

c. Kev
c. Key Remaining Remaining Issues
1. Provide
1. Provide the basis basis for for why the fl.DADhoWe adjustment for contact ho1e adjustment pressure made using the contact pressure old model remains remains conservative.

conservative.

2. Provide
2. Provide an appropriate appropriatebasisbasis for demonstrating demonstrating that thatjoints tighten during jOints tighten during a postulated postulated SLB event.

event. Why is it acceptable acceptable to compare compare the contact contact pressures pressures calculated calculated using original model for NOP the original Nap to the contact pressures pressurescalculated using the new model for calculated using SLB for the Model D5 SGs?

3. If both old andand new models are are conservative, conservative, is is there there an appropriate appropriatebasisbasis to show the relative conservatism of the methods?

relative conservatism 6

LTR-SGMP-09-109 L TR-SGMP-09-1 09 NP-Attachment NP-Attachment To facilitate a continuous response response to the total RAI#4 questions, the questions received received originally (Part A), those received received as follow-up questions questions (Part B) 8) and those identified during the the conference (Part C) are re-arranged 8/11/09 telephone conference re-arranged as noted noted below. The location of responses responses to specific specific questions is shown in in bold type after the question. Also, in the responses, the specific questions addressed addressed by the responses repeated in bold type in the box at the responses are repeated the start of the response.

Part C: Sub a.

Part a.

Discuss if the eccentricity Discuss eccentricity effect on contact contact pressure pressure is occurring as described.

occurring as described. It is the opinion of the NRC staff that opinion that the eccentricity eccentricity effect may not be as as significant significantas as being reported by Westinghouse.

reported Westinghouse. (See (See Section 1.0)

Part PartB B Address following questions questions as part part of response (Vogtle):

response to RAI#4 (Vogt/e):

a. Clarify
a. Clarify the nature nature of the finite finite element model ("slice" model versus axisymmetric axisymmetric SG assembly model) model) used to generate specific information generate the specific information in Tables Tables 6-1, 2,2, and and 3 (and (and accompanying graph accompanying graph entitled "Elliptical "EllipticalHole Factors'J Factors') of Reference 6-15. 6-15. What loads were applied?

applied? How was the eccentricity eccentricity produced produced in the model? (By modeling modeling the the eccentricity as part eccentricity partof the geometry?

geometry? By applying applying an axisymmetric axisymmetric pressure pressure the inside inside ofof bore?) Explain the bore?) Explain why this this model is not scalable lower temperatures.

scalable to lower temperatures. (See Section Section 1.2)

b. Provide table showing maximum delta Provide table delta diameters diameters (total (total diameter diameter distortion) distortion) and maximum eccentricities eccentricities (maximum diameter diameter minus minimum diameter) diameter) from the 3 dimensional (3-~)

dimensional (3-D) finite element analysis analysis for normal operating operating and steam line break break for model F (SLB), for F and 05.

D5. (See Section Section 1.1) 1.1) /

c. In Figure Figure 2 of the White Paper, Paper,add plot for original originalrelationship relationshipbetween reductions reductions in in contact pressure contact pressure and eccentricity eccentricity asas given in Reference 6-15 in the graph graph accompanying accompanying Table 6-3.

Table 6-3. Explain Explain why this original originalrelationship relationshipremains remains conservative conseNative in in light of the new relationship. Explain relationship. Explain the reasons reasons for for the differences differences between the curves.CUNes. (See Section 4.1)

d. When establishing
d. establishing whether contact contact pressure pressure increases increases when going from normal normal operating operating to steam line break conditions, break conditions, how can a can validvalid and conservative comparison conseNative comparison be made if the normalnormal operating operating case is based based on the original delta contact original delta contact pressure pressure versus eccentricity versus eccentricity CUNe curve and the SLB case case is based based on the new cUNe? curve? (See Section

.4.2)

  • 4.2) 7 7

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment Part Part C: Sub b. OtherOther Key Questions

1. The eccentricities
1. eccentricities included Table RAI included in Table appearlarger RAI 4-4 appear than anticipated.

larger than anticipated. Need to confirm that that positive positive contact pressure exists around contact pressure aroundthe entire circumference of the tube entire circumference and state and state this this clearly clearly inin the response. (See Section 3) response. (See

2. The difference difference between initialinitialand and final eccentricity eccentricityincluded included in Table RA14-2 needs needs to be be explained. particular,the exclusive use of the relationship explained. In particular, relationshipbetween initialinitial eccentricity eccentricity and scale scale factor factor in calculating contact pressure calculating contact pressure needs to be justified.

justified. (See Section 1.2)

3. The basis
3. basis for applying the correlation correlation for scale scale factor factor outside an "eccentricity" "eccentricity"range range of of between 1 IE-3 E-3 to 1IE-4 E-4 inch in the calculation calculationof contact contact pressure needs to be further pressure needs further explained. displacements included explained. Values for displacements included in Table 6-18 (of WCAP-17071) suggest suggest that contact that pressuremay be lost at displacement contact pressure displacementranging ranging between 1E-3 1E-3 in to 11E-4 inch.

E-4 inch.

(See Section 2.0)

(See

4. Provide Provide the calculation calculation basis basis for the upper upper andand lower curves provided provided in Figure Figure RAI RAI 4-2.

4-2.

(See Section (See Section 2.1)

5. Resolve the apparent apparent inconsistency inconsistency between Item 4 on page page 25 and the statement statement below Figure regardinghow the model in Figure Figure RA14-1 regarding Figure RA14-1 is loaded.

loaded. (See Section 1.2)

PartC: Sub c. Key Remaining Part Remaining Issues

1. Provide
1. Provide the basis basis for why the !!.Ohole ADhol, adjustment adjustment for contact contact pressure made using the pressure made the remains conservative.

old model remains conservative. (See Section Section 2.2)

2. Provide
2. Provide an an appropriate basis for demonstrating appropriate basis demonstratingthat thatjoints tighten during joints tighten during a postulated postulated event. Why is SLB event. is it acceptable acceptable to compare compare the contact pressures pressures calculated calculatedusing the original original model for NOP to the contact pressures pressures calculated calculatedusing using the new model for SLB forfor the Model D5 SGs? (See Section 2.3) 05 SGs?
3. If both old and new models are conservative, is there an appropriatebasis to show the
3. If both old and new models are conservative, is there an appropriate basis to show the relative conservatism of the methods?

relative conservatism methods? (See Section Section 2.4)

Part Part A: (Original (OriginalRAI#4 from Reference 5)

Reference 1, 1, Page Page 6-69: In Section 6.2.5.3, itit is concluded concluded that the tube tube outside outside diameterand diameter and the tubesheet tubesheet tube tube bore bore inside inside diameter diameter always maintain maintain contact contact in the predicted predicted range range of tubesheet tubesheet displacements.

displacements. However, However, for for tubes tubes with through-wall through-wall cracks cracks at the H* distance, there may be little distance, there little or or no net pressure pressureacting acting on the tube for some distance some distance above H*. H*. In Tables Tables 6-18 and 6-19,6-19, the fourth increment increment in the step that occurs two occurs two steps prior prior to the last last step suggests suggests that there there may be no contact contact between tube and the tube and tubesheet, tubesheet, over a portion portion of the circumference, circumference, for a distance distance above H*. H*. Is conclusion in 6.2.5.3 valid for the entire the conclusion entire H* distance, given the possibility H* distance, possibility that the tubes may contain contain through-wall cracks at that through-wall cracks that location?

location? (See Section 5.0) 8

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment General Background 1.0 General Background on Approach and Models Models Discuss Discuss if the eccentricity eccentricity effect effect on contact contact pressure occurringas described.

pressure is occurring described. It isis the opinion of the NRC staff that opinion that the eccentricity eccentricityeffect may not be as significantsignificant as being reported reported by by Westinghouse.

Westinghouse.

Response

The reference reference structural structural model for the H* H* calculation described in References calculation as described References 8 and 99 is a 3D FEA model that utilizes utilizes the equivalent equivalent properties approach for perforated perforated plates in accordance accordance with Reference Reference 6-15 of the H* H* WCAP WCAP reports. This model model provides provides the tubesheet displacements that are utilized displacements utilized in the calculation of H*. Included Included in the displacement displacement output from the 3D FEA model are the radius and depth dependent x- and y- axis displacements displacements for thethe tubesheet. These displacements displacements are the input to the H* integrator model that uses the inputs to H* integrator calculate contact pressures based on thick-shell thick-shell equations. The tubesheet displacements displacements from from the FEA model indicate indicate that the tubesheet bores become eccentric after application become eccentric application of all thermal thermal and pressure pressure loads. The displacement displacement results from the 3D FEA model are the the difference difference between the completely unloaded case and the fully loaded case for the conditions completely unloaded conditions of interest (i.e., NOP, SLB).

The information information from the 3D FEA model, that the tubesheet tubesheet bores become become eccentric, eccentric, led to a question question regarding regarding continued continued tube-to-tubesheet tube-to-tubesheet contact in the eccentric eccentric tubesheet bore. The The impact of tubesheet out-of-roundness (eccentricity) on the calculation tubesheet bore hole out-of-roundness calculation of tube to-tubesheet tubesheet contact pressures pressures was originally addressed using a scale factor approach as as described described below and in Reference 6-15 of the H* H* WCAP reports. The fit developed developed in in Reference 6-15 , a third order polynomial, Reference polynomial, was appropriate appropriate for the conditions for which itit was was developed developed but itit provided physically impossible impossible results when extrapolated extrapolated significantly outside outside its data basis such as was the case for the SLB conditions for the Model Model 05D5 SGs.

To resolve this issue, aa separateseparate model, model, was developed as described in Section 6.2.5 and shown in Figure 6-48 of Reference Reference 88 and 9, to assess assess tube-to-tubesheet tube-to-tubesheet contact contact under under the fully fully loaded loaded condition (e.g., LlP AP and thermal thermal loading) loading) for the small eccentricities eccentricities that were calculated during the much "colder" "colder" temperature postulated postulated SLB conditions conditions for the Model Model D505 SGs than for the Model F SGs. To properly properly represent the tube in tubesheet condition,condition, this model considered considered a tubesheet tubesheet equivalent cell (the local TS material material around a tubesheet tubesheet bore) and a tube. To address the question address question if if continued contact would exist betweenbetween the tube and tubesheet after the the tubesheet bore becomes eccentric, the tube expansion was analytically simulated simulated to provide a condition of tube to tubesheet contact in a non-eccentric non-eccentric tubesheet bore. This condition was the the reference reference condition condition for the subsequent loading loading of the model by pressure loads (thermal loads loads included) and by applying displacement were not included) displacement boundary boundary conditions conditions (e-bar) to simulate simulate the the expected expected range of tubesheet tubesheet bore eccentricity. The unloaded, post-tube expansion simulation expansion simulation conditions of the model was the reference condition for the displacements conditions displacements provided provided in in Tables 6-18 and 6-19 of the H* References 8 and 9.

H* reports, References 9

LLTR-SGMP-09-109 TR-SGMP-09-1 09 NP-Attachment NP-Attachment While eccentricity eccentricity was the specific focus of this study because because of the question raised about about continued tube to tubesheet continued tubesheet contact in an eccentric eccentric condition, the analytical model model naturally also also provided information on tubesheet bore dilation, provided information dilation, the diametral diametral growth growth of the tubesheet bore represented by the average of the maximum and minimum diameters represented diameters of the eccentric tubesheet eccentric tubesheet bore. Examination Examination of the results from this model,model, as is discussed discussed further below, resulted in two significant conclusions:

1. eccentricities and dilation due to the applied loading For the tubesheet bore eccentricities loading in thethe limiting plants in the models of SG considered, considered, the tube remains remains in contact with the the tubesheet bore.
2. While tubesheet bore eccentricity eccentricity contributes to the reduction in contact contact pressure between between the tube and the tubesheet, tubesheet bore dilation appears to be the the principal principal cause of reduction reduction of contact pressure between the tube and the tubesheet.

pressure between Discussion of 3D FEA Model 1.1 Discussion Model for H*H* Analysis Analysis Provide Provide table showing maximum delta delta diameters diameters (total (total diameter diameter distortion) distortion) and maximum eccentricities eccentricities (maximum diameter diameter minusminus minimum diameter) from the 3 diameter) dimensional dimensional (3-D) finite finite element analysis analysis for normal operating and steam normal operating steam line break (SLB), forfor model F F and and 05.

D5.

Response

The 3D FEA Model Model and its application for determining displacements are determining the tubesheet displacements extensively described in extensively in Section 6 of the H*

H* WCAP reports (References (References 88 and 9). It It is important important to note that the 3D FEA model includes the entire entire tubesheet tubesheet complex (i.e.,

(Le., tubesheet, stub stub

barrel, barrel, channelhead and dividerdivider plate) but excludes the tubes. The model utilizes an equivalentequivalent material material approach approach from Reference Reference 6-5 in the WCAP reports to represent represent the deformation of the the tubesheet under under the applied loading conditions (NOP, SLB/FLB). Displacements Displacements in Cartesian calculated for these conditions at any location coordinates are calculated location on the tubesheet. The The displacements calculated are the changes from an unstressed, room temperature displacements temperature condition after all thermal thermal and pressure loads appropriate to the operatingoperating conditions conditions are applied.

applied. Application Application of a uniform temperature increase temperature increase causes uniform dilation at each tubesheet tubesheet bore. Application Application of pressure pressure loads causes causes distortions distortions in the structure structure due to bending. The 3D FEA model provides provides integrated displacements of each tubesheet integrated total displacements location.

tubesheet bore location.

Table RAI4-1 RA14-1 is a summary summary of the maximum maximum eccentricities eccentricities and <1DsADs for the Model F and Model D5 limiting plants as calculated calculated based on the U displacement) results from URR (tubesheet radial displacement) the 3-D lower SG complex model. model.

10 10

L TR-SGMP-09-1 09 NP-Altachment LTR-SGMP-09-109 NP-Attachment T a bIe RAI41 Table -

RAI4-1:: S Summary M0 d e I 05 ummary 0off Model an d M D5 and 0 de I F Model F NOP NOP and SL BE an d SLB Eccentricity Resu ts ccentrlcity Results SG SG Model Model Elev. Avg. Eccentricity Eccentricity Data Max. Eccentricity Data Max. Eccentricity Data Avg. Ll A 0D Max. Ll Max. AD 0

111

- BTS Above BTS(ll NOP SLB NOP SLB NOP SLB NOP SLB c,e

- _ in in/in in/in in/in in/in in in in in F

in in/in in/in in/in in/in in in in in F

F F

F D5 05 D5 05 D5 05 F I________

F F

D5 05 Eccentricity, e Eccentricity, A C, Ll D, 0o O. A Ll D, 902 D, 90.

Notes:

1. BTS is Bottom of the Tubesheet Plant Plant Condition Condition Value inch/inch inch/inch inch inch inch inch a, c,e a,c,e Byron SLB SLB MAX Byron Byron SLB SLB MIN Byron Byron SLB SLB AVG AVG The The original Table Table RAI4-4 RA14-4 is Millstone Millstone SLB SLB MAX provided here convenience here for convenience Millstone Millstone SLB SLB MIN MIN Millstone Millstone SLB SLB AVG AVG Byron NOP NOP MAX Byron Byron NOP NOP MIN MIN Byron Byron NOP NOP AVG AVG Millstone Millstone NOP NOP MAX Millstone Millstone NOP NOP MIN Millstone Millstone NOP NOP AVG AVG 11 11

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment Discussion of the "Slice" 1.2 Discussion "Slice" Model Clarify the nature Clarify nature of the finite element model ("slice" model versus versus axisymmetric axisymmetric SG SG assembly model) assembly model) used used to generate generate the specific information information in in Tables Tables 6-1,2, 6-1, 2, and and 3 (and (and accompanyinggraph accompanying graph entitled "EllipticalHole Factors")

entitled "Elliptical Factors")of Reference 6-15. What loads loads applied? How was the eccentricity were applied? eccentricity produced produced in the model?model? (By modelingmodeling the eccentricity as eccentricity as part part of the geometry?

geometry? By applyingapplying an axisymmetric axisymmetric pressure pressurethe inside of inside of the bore?)

bore?) Explain Explain why this this model is not scalable scalable to lower temperatures.

temperatures.

I difference between initial The difference explained. In particular, explained.

and final initial and final eccentricity eccentricity included particular, the exclusive use of the relationship included in in Table Table RA14-2 needs to be relationship between initial initial eccentricity eccentricity and scale and scale factor factor in calculating calculatingcontact contactpressure pressureneeds to be justified.justified.

Resolve the apparent apparentinconsistency inconsistencybetween Item 4 on page page 25 and the statement statement below Figure regarding how RA14-1 regarding FigureRA14-1 how the model in the model Figure RA14-1 in Figure is loaded.I RA14-1 is loaded.

Response

The "slice model" is shown in Figure 6-9 of Reference Reference 6-15 in WCAP-17071-P, WCAP-17071-P, WCAP-17072-P, WCAP-17091-P, and WCAP-17092-P.

WCAP-17092-P.

The data in in Tables 6-1,6-1, 6-2, and 6-3 of Reference Reference 6-15 of the H* H* WCAP reports, are derived from this plane stress model ("slice model") developed developed in WECAN/PLUS WECAN/PLUS and the contact pressure equation identified identified on page 6-87 of WCAP-17071-P, page page 6-95 of WCAP-17072-P, WCAP-17072-P, page 6-91 of WCAP-17091-P and page 6-84 ofWCAP-17092-P ofWCAP-17091-P of WCAP-17092-P as described described below.

convenience Tables 6-1,6-2, For convenience 6-1, 6-2, and 6-3 of Reference Reference 6-15 are replicated below and re-named as follows:.

follows:. Table 6-1 is renamed renamed as Table Table RAI4-2, Table 6-2 is renamed as Table RAI4-2, Table RAI 4-3, and RAI4-3, Table 6-3 is renamed as Table RAI4-4.

The "initial" eccentricities eccentricities (defined as DMAX DMAX - DMIN)

D M1N ) applied in in the "slice" "slice" model in in Table RA14-3 RAI4-3 and Table RAI4-4 RA14-4 are directly incorporated incorporated into the model geometry. That is, the initial eccentricity eccentricity is built into the model model geometry. The eccentricity eccentricity values in the model were assumed values for tubesheet tubesheet tube bore deformation based deformation based on engineering engineering judgment and prior prior experience.

experience.

In the "slice" In "slice" model model analysis, the tubesheet is assumed to have a thermal expansion coefficient expansion coefficient of zero (0) in/infOF in/in/°F and the tube materialmaterial is assumed to have the appropriate appropriate ASME Code Code thermal expansion expansion coefficient coefficient values. (The TS coefficient coefficient of thermal expansion expansion is set to zero to provide a loading loading mechanism mechanism for the model. When a temperature temperature is applied, the tube "grows" "grows" into the tubesheet tubesheet collar. The temperature temperature difference difference applied applied to the tube in the "slice" model was was 500°F, for a total tube temperature temperature of 570°F. [Applied 500°F + 70°F assumed assumed room temperature]). The sole purpose of the development temperature)).* development of the "slice" "slice" model model was to provide a sensitivity study to relate the effects of assumed eccentricity eccentricity (DMAX D M1N ) conditions to contact (DMAx - DMIN) pressures from which the contact pressure ratios ratios were developed. No attempt was made to developed.

12

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment reproduce the contact pressurespressures that would be calculated by the 2-D axisymmetric model that was previously used to develop develop the tubesheet displacements.

The "final" eccentricity eccentricity (DMAX (DMAX - D M1N ) values in Table RA14-3 DMIN) RAI4-3 and Table RAI4-4 were also Table RA14-4 determined using the "slice model": The final eccentricity eccentricity values are the (DMAx- (DMAX - D M1N ) results of DMIN) applying the loading conditions on the slice model: The loads applied to the "slice" "slice" model were thermal loads only as follows:

thermal o

0 psig - Primary Side Pressure Pressure o

0 psig - Secondary Side Pressure Pressure 500°F-Tubesheet~T 500 'F- Tubesheet AT 500 OF- Channel Head ~

°F_ Channel ATT 500 OF- ~T

°F_ Shell AT As discussed Reference 6-15, Table RA14-3 discussed in Reference constructed using the displacement RAI4-3 was constructed displacement results results from the plane stress model analysis analysis for the elliptical holes along with the contact pressure pressure equations. The effective change diameter was calculated as follows using a series of change in hole diameter assumed scale factors:

assumed a,c,e a,c,e I1 The ~DMAX

[ a ADMIN were taken from the radial and circumferential ADMAx and ilDMIN

] (RAI4-1)

(RAI4-1) circumferential changechange in tube bore "slice" model.

diameter in the "slice" model.

corresponding contact pressure for each The corresponding factor was then determined each scale factor determined as follows:

K

[ I"

]

a,c,e a,c,'

(RAI4-2)

(RAI4-2)

RA14-2 is a generic Equation RAI4-2 Equation representation of how tube to tubesheet contact pressure is generic representation is calculated in the H*

calculated H* integrator spreadsheet analysis. The equation integrator spreadsheet equivalent to the equation equation is equivalent equation for P2 shown on page 6-87 in WCAP-17071-P, page 6-95 in WCAP-17072-P, in WCAP-17071-P, WCAP-17072-P, page 6-91 in in WCAP-10791-P and page 6-84 in WCAP-17092-P.

WCAP-10791-P WCAP-17092-P.

eccentricity in Table RAI 4-3 result in contact pressure ratios The scale factors for a given input eccentricity ratios using the thick shell equations that are equal to the contact pressure pressure ratios calculated using the the "slice" model for initial eccentricities (defined as DMAX - DMIN)

"slice" model for initial eccentricities (defined as DMAX - DM1N ) equivalent equivalent to 0.0002, 0.0002, 0.0004, 0.0006 and 0.0008 inches, respectively, compared compared to the contact pressurespressures for a circular holehole (DMAx (DMAX - DMIN =0). These These scale factors are identified in bold print in Table RAI4-3. The data for eccentricity was fit by a third order polynomial equation the scale factors as a function of "initial" eccentricity equation provided on page 6-85 of WCAP-17071-P WCAP-17071-P and page 6-86 of WCAP-17072-P.

13

LTR-SGMP-09-109 L NP-Attachment TR-SGMP-09-1 09 NP-Attachment Based on a review of Table RA14-3 RAI4-3 and Table RA14-4, RAI4-4, the scale factor [ ]a,c,e is the the appropriate scale appropriate scale factor for calculating calculating a reduction factor for contact reduction factor for contact pressure of [ pressure of [ I ace

] a,c,e associated associated with an initial eccentricity eccentricity of [ ((DMAX - DMIN)/

] a,c,e ((DMx DMIN)/ [ inch) from the

]a,c,e inch) the "slice" "slice" model. The scale scale factorfactor of [ ]a,c,e relates to a contact pressure reduction factor of

[ ]a.c.e and corresponds

]5.c.e corresponds to an initial eccentricity eccentricity of [ ,c,e inch, and so forth.

))a,c,e The "final eccentricity" values corresponding to the same scale scale factors highlighted in bold in Table RAI 4-3 (and Table Table Table RAI4-4) are not used in determining determining the reduction reduction in contact pressure because because the resulting third order polynomial polynomial relationship relationship between scale scale factor and and eccentricity is bounded by the relationship eccentricity relationship for "initial eccentricity", eccentricity", i.e., the resultant resultant scale scale factors, and hence the reduction reduction in contact pressure due to eccentricity, would would be less using the the third order fit resulting from the "final" eccentricity eccentricity values from Table RAI 4-3. For example, example, for an eccentricity eccentricity of 1E-3 in/in, in/in, the scale scale factor is [ I] a,c,e as compared to [ ]ace for the trend

]a,c,e line associated associated with the "initial" eccentricity eccentricity results. Figure Figure RAI 4-1 illustrates this. This figure shows a comparison comparison of the trend line analysis for "initial" eccentricity eccentricity and "final" eccentricity.eccentricity.

Referring Referring to Equation RAI 4-1, 4-1, larger scale factors result in a greater greater reduction in contact pressure due to eccentricity.

pressure eccentricity.

Table Table RAI4-2 Reproduced Table Reproduced Table 6-1 of ReferenceReference 6-15 6-15 Sleeve Sleeve O.D. 0.0. 0.0.

Tube O.D.

Eccentricity Eccentricity Oelta(1) lL)

Delta"'T(

- I Average(1) fin( 3 ) ( 1) (2) 1 Sinm'h (inch) Awnrnr p( ) i Ratio(3) rn3it Oelta(1) (2) A, Average(1) (1) iD ý (3)

Ratio(3) a,c,e a,c,e 0.0000 0.0002 0.0004 0.0004 0.0006 0.0006 0.0008 L _____

Notes: This table-ts table IS developed from the model shown in Figure RAI4-1, RA14-1, below.

1. The units of these columns columns are stress stress in in psi.
2. The "delta" "delta" in in this table refers to the maximum deviation deviation from aa constant value of the mean linearized linearized radial stress around the tube bore.
3. The ratio is calculated by dividingdividing the contact contact pressure pressure between between the tube and the tubesheet at aa given eccentricity eccentricity by the contact pressure between the tube and the tubesheet tubesheet in in a round tube bore (e=O.O).

(e=0.0). ForFor example, the ratio of (( 1] 8.C ** calculated

".c.e calculated in in Table 6-1 is a ratio of the average contact pressure at an eccentricity of 0.0002 in eccentricity of [

in of[ ]",c.* psi divided by the average contact pressure at an eccentricity

]Oa,c, eccentricity of

[L ] ..... psi.

[ J8.C ** psi.

14

LLTR-SGMP-09-109 NP-Attachment TR-SGMP-09-1 09 NP-Attachment Table Table RAI4-3 Reproduction of of Table 6-2 of Reference 6-] 6-155 Primary Pressure Primary 0 psig psig Secondary Pressure Secondary 0 psig psig Tubesheet Delta T Tubesheet 500 500 0F of Delta T Shell Delta 500 OFF Channel Head Delta T 500 500 oF OF Sleeve OD DeltaDelta D D ]a,c,e irI in Tube ID ID Delta DD [ ] a,c,s ir in Tube OD Delta D (Thermal) [c. ] a,c,e i

in Sleeve/Tube Interaction SleevelTube Coefficients Interaction Coefficients [ ]-,c

] a,c,a,e Tube/Tubesheet Interaction Coefficients Tube/Tubesheet Interaction [ ] 'll"

] a,c,a Eccentricity (1))

(1 (2) (3) (4) (5 (5) 6 76)

Final Hole Delta Hole Delta Hole Delta S/T SIT T/TS TITS Initial Initial (inch) Max/Min Max/Min D (0 D (0 Deg)

Deg) D (90 Contract Contact Ratio (inch) (inch) Combination DDg(90 rsuePesr Contact Contract Ratio (inch) ~,Combination a,c,e

,c,e Deg) Pressure Pressure Pressure

~

- ~

a,c,e 0.0000 Minimum Minimum -

Average Average Maximum Maximum 0.0002 Minimum Minimum Averae Avera e a, a,e ,9 Maximum Maximum 0.0004 0.0004 Minimum Minimum

~era e a, Avera a, ,e Maximum Maximum L-

- L-15

LTR-SGMP-09-1 09 NP-Attachment LTR-SGMP-09-109 NP-Attachment Table RAI4-3 (Cont'd.)

a,c,e a,c,e a,c,e Eccentricity a,c,e Eccentricity (1) (2)

(2) (3)

(3) (4)

(4) (5) (6) _

r- - r-0.0006 F Minimum Minimum F Averagea,c,e A_.vveragea'c'e Maximum

--Maximunm 0.0008 Minimum Average a,c Maximum Note: The values in Bol-d Bciid identify the source data for Table source data Table RA14-3 RAI4-3 Table RAI4-4 RAI4-4 Reproduction Reproduction of Table 6-3 6-3 of Reference Reference 6-15 6-15 Nominal HoleHole Diameter I 1a,c,e a,c,e F- 1 Eccentricitv( )

Eccentricity(1)

Initial Initial Pressure Delta (in/in)

(in/in) Ratio Dia Final Max/Min Max/Min (in)

(in) (in/in)

(in/in) Factor Factor a,c,e 0.0000 I

0.0002 0.0004 0.0004 0.0006 0.0008 (1)) These kI I Isb values are the values are the values ir Initial Vaalues for Inial and anid final final eccentricity RAI4-2 are divided eccentricity from Table RA14-2 divided by the the tubesheet hole nominal tubesheet nominal diameter ((

hole diameter ]a,c,e t,c,e a,c,e 16

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment a,c,e.

a,c,e RAI4;..2: Scale Factor Comparison (Initial versus Final Eccentricity)

Figure RAI4-2:

The method for calculating "old" method for the Model FF SGs calculating the contact pressure for using the "old" SGs (all plant conditions) conditions) and the Model D5 SGs (NOP and FLB conditions) and the "new" "new" method for calculating the contact pressure the ModelModel D5 SGs only (SLB conditions) are described below:

Old Method (Reference 6-15):

1. The U circumferential and radial .1D URR used in the calculation of the circumferential AD is based on the linearly scaled 2D axisymmetric FEA model (3-D model for the current H* H* analysis) of the lower SG complex circumferential and radial .1D's
2. The circumferential determine AD's are used in the scale factor (SF) equation to determine ADhole the .1D RAI4-1) that is used to determine the reduction in contact pressure (see equation RAI4-1) ho1e (see (e), equation RAI4-2.

as a function of eccentricity (e),

between 11 relationship between

3. The relationship 11D on the 2-D plane model shown in Figure 6-9 D and e is based on Rev.1.

of SM-94-58, Rev.1.

17

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment

4. The model model in Figure Figure 6-9 of SM-94-58, Rev.1 includes the initial applied eccentricities eccentricities (OMAX (DMAX --

OMIN) geometry DMIN) geometry definition definition of the model.

5. The "slice" "slice" model provides provides the input for using the SF relationship (Eqn. RAI4-1). The SF is determined determined by comparing the "slice" "slice" model results to the axisymmetric axisymmetric model results for aa TS collar and tube model at a given radius in the TS over the full thickness thickness of the TS.
6. The result is then used to calculate calculate the reduction in contact contact pressure pressure as a function of TS TS elevation and radius due to TS displacement elevation displacement and tube bore eccentricity.

eccentricity. This is appropriate appropriate because the conditions for the Model because Model F SG and Model 05 D5 SG (NOP and FLB conditions) conditions) are within the range of datadata for which the scale scale factor relationship is applicable.

Method (WCAP-17071-P, New Method WCAP-17072-P):

(WCAP-17071-P, WCAP-17072-P):

1. The U circumferential and radial ~O URR used in the calculation of the circumferential AD comes from a 3-D 3-D FEA model model of the lower SG complex with condition-specific condition-specific inputs inputs applied.

circumferential and radial ~O's

2. The circumferential AD's are are compared determine the maximum ~O compared to determine AD that will give the maximum reduction in contact maximum reduction contact pressure pressure as a function of eccentricity eccentricity (e).

(e).

between ~O

3. The relationship between AD and e is based on the 2-D [ la,c,e model shown lace WCAP-17071-P and WCAP-17072-P, section 6.2.5. The model in WCAP-17071-P model is shown in Figure 6-49 of the WCAP reports. The range of eccentricityeccentricity used in this study conservatively exceeds the values of tube bore eccentricity conservatively exceeds eccentricity calculated from the the perforated perforated TS model in Section 6.2.4.
4. The model in Figure 6-49 of the H* WCAP reports applies boundary boundary conditions to the the outer outer edge edge of the tube pitch material material and does not directly directly affect the material material that is deforming in the tube and tubesheet cell.

deforming

5. The TS deformations deformations and tube to tubesheet contact pressure pressure results that produce the the maximum reduction maximum reduction in contact pressure at the minimum value of TS tube bore bore eccentricity are then fit with a linear relationship.

eccentricity

6. The result of the linear relationship is used to determine determine the reduction in contact pressure between the tube and the tubesheettubesheet directly.

directly. There are no intermediate intermediate equations equations or results.

A correct prediction of contact pressure pressure loss requires the knowledge of both the proper proper values of OMAX DMAX and associated OMIN associated DMIN with the different pressure different pressure and temperature conditions at a given given tubesheet elevation as well as the value of eccentricity.

tubesheet radius and elevation eccentricity. The values of OMAX DMAX and DMIN are a OMIN deflection of the tubesheet, URI a function of the radial deflection UR, as determined determined by the finite finite element element analysis model model (which previously previously was a 2-D axisymmetric model model of the SG lower lower 18

LTR-SGMP-09-109 LTR-SGMP-09-109 NP-Attachment NP-Attachment assembly assembly and at present, is aa 3-D model model of the SG lower lower assembly). The results from the the "slice" model cannot be linearly linearly scaled temperatures because the method of super-scaled to lower temperatures position has been been shown during the development development of the current H* H* analysis to not apply to the the non-linear non-linear combination combination of materials and loading in the lower SG complex. This conclusion led to the development development of the 3D FEA model that is the reference reference model for the H* H* analysis. A A discussion discussion of this is provided in Section Section 6.1.2 ofWCAP-17071-P of WCAP-17071-P and WCAP-17072-P.

WCAP-17072-P.

1.3 Discussion Discussion of the Unit Cell Model Model to Calculate Calculate Contact Pressures Pressures The "Unit Cell" model is extensively extensively discussed in Section 6.2.5 of the H* H*WCAPs (References (References 8 and 9). The specific goal of this model was to determine determine ifif tube to tube contact contact would remain when the tubesheet is deformed due to operating operating loads. An equivalent tubesheet tubesheet cell is modeled, that is, a tubesheet bore with surrounding modeled, surrounding tubesheet tubesheet material, and a tube in in the the tubesheet tubesheet bore (see Figure 6-48 of the H* H* WCAPs). For the primary primary purpose of this model - to study ifif tube-to-tubesheet tube-to-tubesheet contact is present present during the limiting tubesheet deformations - the tubesheet deformations the model was initialized by simulating simulating the tube expansion process. The expansion expansion process was was conservatively simulated conservatively simulated by applying a low value of expansion expansion pressure [ 1ac,e inside

]8.c.e inside the tube, resulting in initial tube to tubesheet tubesheet contact, and then removing removing the tube expansion internal pressure. The calculated calculated dilation of the tubesheet bore due to the simulation simulation of the tube tube expansion is (( ] 8,C,e a,c,e inch for all models of SG considered.

As discussed in Section 6.2.5 of the H* H* WCAP reports, the operating pressure loads, were were applied applied to the initialized initialized model in a sequential manner, and the resulting contact pressures pressures were calculated when a range of displacements calculated displacements (termed "E-bar") OlE-bar") were applied applied as boundary conditions to the model. Figure RA14-2 RAI4-2 shows the updated updated sequential loading (includes loading (includes application application of thermal thermal loads) of the model and relates it it to the steps discussed in Section 6.2.5 Section 6.2.5 and Tables 6-18 and 6-19 of the H* H* WCAPs. The "E-bar"OlE-bar" values shown as the displacement displacement inputs on Tables Tables 6-18 and 6-19 in the H* displacements (in H* WCAP reports are uni-directional displacements (in inches) inches) that are NOT the same as eccentricity eccentricity and also not the same as AD. (Eccentricity

~D. (Eccentricity is defined defined as the difference difference between the maximum maximum and minimum diameters of a bore divided by by the nominal diameter of the bore. The units of eccentricity eccentricity are inch/inch.)

inch/inch.) The displacement displacement inputs inputs applied applied to the unit cell model are assumed values that based on prior analyses that envelope the expected tubesheet envelope displacement for all of the applicable tubesheet displacement applicable operating operating conditions. ItIt is is important important to note that the unit cell model as described described in Section 6.2.5 of the H* H* WCAP reportsreports utilizes boundary conditions chosen to minimize minimize the tube-to-tubesheet tube-to-tubesheet contact pressures pressures for the the applied relative relative displacements.

displacements.

To interpret the results from the unit cell model model properly, the following must be observed:

observed:

    • To address if tube to tubesheet contact continues for all the assumed tubesheet displacements, displacements, the appropriate reference reference condition is the initialized condition (after Step 4) of the model that simulatessimulates a tube expanded in the tubesheet bore.

19

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment

  • To compare the results of the unit cell model with the 3D FEA model, the appropriate appropriate reference condition of the unit cell model is the initial model reference model (Step 0) without the tube tube expansion simulated and thermal loads must be included.

Figures RAI4-3 and RA14-4 Figures RA14-3 RAI4-4 show the average average tubesheet tubesheet bore dilation (AD) (L10) as a function of tubesheet relative displacement displacement (E-bar) for the Model F and Model Model D5.05. The average average tube bore dilation at zero E-bar input is the result of the temperature temperature and pressure loadingloading of the unit cell model. Initially, application application of the displacement displacement input "E-bar" "E-bar" results in more significant hole hole dilation, but rapidly takes on a shallower slope as the applied applied displacement displacement increases. The The curves are characteristically characteristically the same for the Model Model F and Model 05 D5 steam generators generators and also for the different different operating operating conditions, NOP and SLB, for the different models of SGs.

Similarly, Figures RA14-5 RAI4-5 and RAI4-6 RA14-6 show the tubesheet tubesheet bore eccentricity eccentricity "e" "e" as a function of tubesheet relative displacement tubesheet displacement (E-bar) for the Model Model F and Model D5. Eccentricity initially

05. Eccentricity initially increases increases with application application of the displacement displacement boundary condition (E-bar) simulating the load due to pressure pressure differential across across the tubesheet, but the rate of increase decays with increasing increasing E-bar. A significant difference is noted between significant difference between NOP and SLB conditions conditions at large values of E-bar. This difference reflects the fact that the uniform growth of the tube bore hole due to to increased temperature overwhelms increased temperature overwhelms the effect of application application of the displacement displacement boundary condition (E-bar) on tubesheet bore eccentricity. eccentricity. During the SLB event, the temperaturetemperature is decreased decreased and the differences differences in DMAX OMAX and DMIN OMIN remain more significant significant as the displacement displacement boundary condition is increased, although although the rate of increase difference between DMAX increase in the difference OMAX and OM IN is reduced DMIN reduced at some point. point.. . Eventually, at NOP conditions, the difference difference between between DMAX OMAX and DMIN OMIN tends to become decrease even though a greater decrease greater displacement displacement (E-bar) is applied, applied, leading to a reduction reduction of eccentricity eccentricity "e.""e."

RAI4-7 and RA14-8 Figures RA14-7 RAI4-8 show the contact pressure as aa function of tubesheet relative relative displacement displacement (E-bar) for the Model Model F and Model D5 05 for both NOP and SLB conditions conditions based based on the unit cell model. As expected, both NOP and SLB contact pressure pressure decrease decrease with increasing increasing displacement inputs, ultimately going to zero at a very large value of applied displacements.

displacement displacements. It It is to be noted that the maximum displacement displacement assumed assumed is significantly greater than would be be predicted predicted by the 3D FEA model. Over the entire range of assumed displacement displacement conditions, the the SLB contact pressure pressure exceeds that for NOP conditions.

RAI4-5 summarizes Table RA14-5 summarizes the eccentricity, eccentricity, L10 AD and predicted contact pressure using the unit cell model for various values of applied displacement (E-bar) for both the model F and Model applied displacement Model D5 05 SGs. The true true eccentricity eccentricity ([Omax-Omin]/Onom)

([Dmax-Dmin]/Dnom) is shown for the appliedapplied displacement, E-bar.

Table RAI4-5 RA14-5 also provides aa comparisoncomparison of the L10 AD predicted by the unit cell model for the two reference reference conditions conditions notednoted above, that is, for the total L10 AD from the model withoutwithout the simulated simulated tube expansion (reference(reference step 0 in Table 6-18) and for the initialized initialized case with the tube expansion simulated simulated (reference (reference step 4 in Table 6-18).

20

LTR-SGMP-09-1 L TR-SGMP-09-1 09 NP-Attachment NP-Attachment Further, Table RAI4-5 RA14-5 provides aa summarysummary of contact pressures pressures between the tube and the the tubesheet for various applied tubesheet applied values of E-bar for the Model F and Model Model D505 SGs. The "Modified "Modified Contact Contact Pressure" is the "Raw Contact Pressure" from the unit cell model adjusted for the actual tube expansion expansion process ([ ([ compared to the simulation at [

]a,c,e psi compared

]a,c,e I] a,c,e a,c,e psi) real Model F and Model D5 geometry and more realistic operating 05 geometry pressures and operating conditions of pressures temperatures.

temperatures. For all cases of applied displacement, displacement, positive contact pressure between pressure remains between the tube and tubesheet. It It should be noted that the largest value of applied displacement (E-applied displacement (E-bar) is well in excess excess of the displacement displacement predicted by the 30 3D FEA model.

Table Table RAI4-6 RA14-6 provides similar data to that in in Table RAI4-5, except that the data is based on the the 3D FEA model.

30 Comparison of Tables RA14-5 RAI4-5 and RA14-6 RAI4-6 leads to the following observations:

1.The 1.The ADs

~Os from the 30 3D FEA model are significantly significantly less than the corresponding corresponding ~Os ADs from the the unit cell model from the unloaded unloaded to the fully loaded (i.e., from step 0 to step 9) for loaded condition (Le., for both NOP and SLB conditions. This leads to the conclusion that the unit cell model displacement results and contact pressure displacement predictions conservatively pressure predictions conservatively represent the referencereference 3D FEA model results.

30

2. The eccentricities eccentricities from the unit cell model are generally comparable to those from the 3D 30 FEA model. A more exact comparison is difficult difficult based on the available data; however, itit is clear that the actual range of eccentricities eccentricities from the 30 3D FEA model was adequately adequately addressed by the unit cell model.
3. The method of Reference Reference 6-15 of the H* H* WCAP report for adjusting contact pressure provides provides acceptable acceptable results for all conditions conditions except the SLB condition for the Model Model 05 D5 SGs The The Reference 6-15 significantly method of Reference significantly under-predicts under-predicts contact pressure for the ModelModel D5 05 SLB conditions.

conditions. Referring to Figure RAI4-6, the method for calculating calculating the reduction in contactcontact pressure defined by the White Paper, when adjusted adjusted for temperature temperature effects, shows that SLB contact contact pressure is increased increased relative to normal operating operating conditions.

conditions.

21

LTR-SGMP-09-1 09 NP-Attachment LTR-SGMP-09-109 NP-Altachment RAI4-5 Table RA14-5 Eccentricity, Contact Contact Pressure Pressure and ~D AD Results Results from Unit Unit Cell Model Square Cell Results Square Cell Results Square Square Cell Results Square Square Cell - Average Delta D Raw Contact Raw Contact Modified Modified Contact Rt*n N[2)- Rt*n cl(3)

Frc.e.*nt rinitv Pressure(1) Preslure(1)

Pressure(1) Step Step 9(3) Step 4(4) - Step 9(3)

Eccentricity 1 0(2) -

Ecrenricit Sn 5tep 0(2) - Stp9' Step 4(4) - Sten 903)

SG SG "E bar" NOP SLB NOP SLB NOP SLB NOP SLB NOP SLB "E bar" NOP SLB NOP SLB NOP SLB NOP SLB NOP SLB a,c,e a,c,e Model

- in in in/in in/in in/in in/in si psi psi psi psi psi psi psi in in in in in in in F

F F

F F

D5 D5

_D5 D5

_D5 D5 D5 D5

~

Notes:

1. Accounts for expansion pressure and geometry.
1. Accounts for expansion pressure and geometry.
2. See
2. See Section 6.2.5 H' Section 6.2.5 H*WCAP. Step 0 is the condition of the unit-cell model prior to any modifications for tube expansion, loading, etc.

WCAP. Step 0 is the condition of the unit-cell model prior to any modifications for tube expansion, loading, etc.

3. See
3. See Section 6.2.5 H*

Section 6.2.5 WCAP. Step H' WCAP. Step 99 is the condition is the of the condition of unit cell model after all loading conditions have been applied.

the unit cell model after all loading conditions have been applied.

4. Section 6.2.5 See Section
4. See H' WCAP.

6.2.5 H*

Step 4 is the initialized condition of the Unit Cell model after tube expansion has been simulated.

WCAP. Step 4 is the initialized condition of the Unit Cell model after tube expansion has been simulated.

22

L TR-SGMP-09-1 09 NP-Atlachment LTR-SGMP-09-109 NP-Attachment Table RAI4-6 RA14*6 Eccentricity, Eccentricity, Bore Dilation and Contact Contact Pressure from 3D FEA Model II Hstar Analysis

_OP Ec.ce.ntricitv Eccentricity SLB Ava Hstar Analysis Avg. Cnntne.t NOP Analysis Contact Pr*.*ure.

Pressure tPs Hstar Analysis Hstar No No Analysis - Avg.

Nn ILoad had tn On*r*tinn to OperatinQ SLB SLB SLB A 0D AVQ. l!.

NOP NOP SLB SLB NOP NOP SLB SLB NOP Model and Contact Pressure SG Model a,C,e a,c,e Reduction Model Reduction ,- in/in inlin in/in in/in psi psi in in -

F - Ref. 6-15 F 6-15 Limiting Radius Radius - F - Ref. 6-15 6-15 D5 - Ref. 6-15 05 6-15 05 D5 - White White Paper Limiting Radius - D5 Limiting 05 - Ref. 6-15 6-15 Limiting Limiting Radius - D5 05 - White Paper Paper I FF - Updated Model (1)(1) 05 D5 - Updated Updated Model (1)(1)

(1):

(1): Updated Model Results Updated MOdel based on Iesults based on eSIimates etimates from trom approximate values in approximate values element anal in finite element y sis and analysis and do not reflect do not reflect the result of a regression the result analysis.

23 23

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment RAI4-2 Figure RA14-2 Unit Cell Model Model and loading Loading Sequence Sequence (1)

(1 ) (2) (3)

(3)

Loading Steps:

O.

0. Initial Model
1. Initial Tube to TS gap gap
2. Pressurize Pressurize tube to 16ksi
3. Pressurize tube to 28ksi
4. Release Pressure on Tube Tube
5. Apply ATV1 )

Apply ,n(l)

6. Apply "E-bar" "E-bar"

~P=[

7. Apply AP=[ la.c

]apcse.* psii

~P=[

8. Apply AP=[ la.c

]a.....* psi psi

~P=[

9. Apply AP=[ la.c

]ace.* psi psi Step 0 Step 5 Step 6-9 6-9 Notes: (1) The application of the unitunit AP =

boP = 0 boP =

Ap= 0 AP>

boP> 0 cell model model in support support of Tables 6-186-18 AT = 0 boT = 0 AT= 0 6.T= 6.T>

AT>00 and 6-19 does not include application of AT.

oft.T.

application Unexpanded Unexpanded Tube Tube Expanded Expanded Tube Expanded Expanded Tube e=O e=0 e=O e=0 e>O e> 0 e bar =

e = 0 e bar =0 ebar=0 e bar > 0 ebar>0 24

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-1 09 NP-Attachment a,c,e RAI4-3 Figure RA14-3 Relationship between Relationship between "E-bar" "E-bar" and AD; Model Model F a,c,e a,c,e RAI4-4 Figure RA14-4 Model D5 Relationship between "E-bar" and AD; Model 05 25 25

LLTR-SGMP-09-109 NP-Attachment TR-SGMP-09-1 09 NP-Attachment a,c,e a,c,e Figure RA14-5 Figure RAI4-5 Relationship between between liE-bar" "E-bar" and Eccentricity Eccentricity "e"; Model F a,c,e Figure Figure RAI4-6 RA14-6 Relationship Relationship between between "E-bar" liE-bar" and and Eccentricity Eccentricity "e"; Model D5 "e"; Model 05 26 26

LLTR-SGMP-09-109 TR-SGMP-09-1 09 NP-Attachment NP-Attachment a,c,e RAI4-7 Figure RA14-7 Relationship between Relationship between "E-bar" liE-bar" and Contact Pressure; Pressure; Model Model F a,c,e a,c,e Figure RA14-8 Figure RAI4-8 "E-bar" and Contact Relationship between liE-bar" Contact Pressure; Model 05 D5 27 27

LTR-SGMP-09-109 LTR-SGMP-09-109 NP-Attachment NP-Attachment 2.0 Comparison Comparison of Slice Model and Unit Cell Model Results Model Results The basis basis for applying applying the correlation correlationfor for scale factor factor outside outside an "eccentricity" "eccentricity"range range of of between 1 1E-3 E-3 to IE-4 inch 1E-4 inch in the calculation calculation of contact contact pressure pressure needs to be further explained. Values for displacements explained. Values displacements included included in Table 6-18 (of WCAP-17071)

WCAP-17071) suggest that contact that contact pressure pressuremay be lost at at displacement displacement ranging ranging between 1 1E-3 E-3 in to 1 1E-4 in.

E-4 in.

Response

Interpretation of the displacements Interpretation displacements noted in in Table 6-18 of the WeAPWCAP reports was clarified in the the prior response, Section 1.3. 1.3. The values noted in in the column titled "Displacement Total" refer to to the condition of the unit cell model after Step 4 <;>f of the loading sequence sequence (See Figure RAI4-2).

When the true reference reference condition (Step 0) for total displacement displacement is considered, the values of total displacement displacement are significantly largerlarger as noted previously.

Westinghouse agrees that the derivation of the fit in Westinghouse in Reference Reference 6-15 is non-intuitive non-intuitive and limited limited in its application.

application. However, the results of applying the fit described reference 6-15 are described in reference acceptable acceptable relative to a best case finite elementelement model (unit cell with thermal and ~P AP loading) for the reasons reasons described below.

Westinghouse Westinghouse also agrees that the fit that describes describes the reduction in contact pressure for the the steam steam line break condition in the Model D5 05 White Paper does not account account for the reduction in reduction contact contact pressure due to tube bore dilation in the same same manner as the fit described described in Reference Reference 6-15. The results of using the fit described described in Reference Reference 6-15 also match match the expected expected trend from aa best case finite element model.

model. See the response to b.4 below for more details.

A series of tubesheet tube bore eccentricities eccentricities were applied to the tubesheet cell model model and combined combined with different pressure and temperature temperature loads. The average, maximum maximum and minimum minimum values of the tube-to-tubesheet tube-to-tubesheet (TITS)

(TITS) contact pressures pressures around the circumference circumference of the tubetube were reported. The valuesvalues of tubesheet tubesheet relative relative displacement, temperature that displacement, pressure and temperature were used in the analysis are summarized summarized in the table below.

Input Conditions for Unit Cell Model Input (no correlation implied)

Internal Internal Temperature Temperature e Pressure Difference Difference in in AP,

~P, psi AT,OF

~T, OF ace a,c,e 0.00 -

2.0E-04 2.0E-04 4.OE-04 4.0E-04 28

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment Normal operating operating (Nap)(NOP) conditions in the Model Model 05 D5 and Model F steam generators are represented by a AP of ((

represented ]a,c,e psi and a AT of (( ] a,c,e of.

OF. Main steam line break (SLB) .

conditions in the Model D5 05 are represented represented by a AP of (( " psi and a AT of [ )) a,c,e of.

)) a,c,e OF.

The value of AP in in the tubesheet cell can change change as a function of elevation in the tubesheet due due to the distribution of crevice pressure. The results of the study include include the data for a depth ratio ratio of 0.9 which is an elevation elevation roughly 2 inches below the top of the tubesheet. The values of AP AP represented represented in this study account account for the region of interest near the top of the tubesheet tubesheet where where the maximum maximum eccentricity eccentricity in in the tubesheet tubesheet is expected expected and where the crevice crevice fluid is transitioning from the crevice crevice conditions to the secondary secondary side fluid conditions. The region roughly 2 inches inches below the top of the tubesheet tubesheet is also where a significant portion of the TITS T/TS contact pressure develops develops so itit is a good indicator indicator of trends in the effect that different operating operating conditions conditions have on the contact pressure.

The original original results in section WCAP-1 7071-P were used to verify that the reduction in section 6.2.5 of WCAP-17071-P in T/TS contact pressure TITS pressure as a function of tubesheet tubesheet tube bore eccentricity eccentricity was appropriate appropriate for thethe Model Model F SG. The original relationship that is used to define the reduction reduction in TITST/TS contact pressure as'a function of eccentricity eccentricity is described described in section 6.3 of WCAP 17071-P 17071-P and and WCAP 17072-P. However, the result of applying the fit described described in section 6.3 to the Model D5 05 SG during during SLB was shown to be inconsistent with the expected trend from the more detailed analysis described described in in section section 6.2.5. The results of section 6.2.5 were then used to define a new relationship between relationship between the reduction in TITS T/TS contact pressure and tube bore eccentricity. eccentricity. This This

\

new relationship is described described in the Model D5 05 White Paper (Reference (Reference 12). Figure RA14-8 RAI4-8 shows the result of applying the new new relationship to the Model D5 05 SLB conditions (i.e., White conditions (i.e., White rd Paper Paper results, Reference Reference 12) in comparison comparison with the results from the old 3 3 rd order polynomial relationship.

relationship. Because Because the tubesheet tubesheet temperature induced hole dilation, potentially the most dilation, potentially significant significant factor in in contact pressure reduction, was not considered in the Model Model D5 05 condition condition results, a third curve curve was added to the figure titled "Model D5 05 FEA trend." This curve represents represents the most accurate accurate calculation of the contact pressure pressure ratio.

Figure Figure RAI4-9 RA14-9 shows the contact pressure pressure ratio (PCSLB/PCNoP)

(PCsLB/PCNoP) as a function of tubesheet relative displacement, displacement, E-bar. ItIt is clear from Figure RA14-9 RAI4-9 that the results of using the old fit for the Model 05 D5 SLB are inconsistent inconsistent with the more detailed detailed analysis. At SLB conditions, the the tubesheet bore dilation is relatively relatively larger than at Nap NOP conditions conditions due to the increased increased bending of the TS and decreased decreased thermal expansion. Therefore, Therefore, it it is expected that the T/TS TITS contact pressure pressure ratio should increaseincrease by aa factor of at least [ ]a,c,e ]a,c,e (see Figure RAI4-9)

RAI4-9) when going from NOP Nap to SLB. It It is also expected expected that the tube to tubesheet contact pressure pressure should decrease with increasing decrease increasing tube bore eccentricity.

eccentricity. The H* H* results using the old fit for the Model D5 05 clearly do not follow either expectation expectation from the detailed analysis. However, when the new fit fit results are applied applied to the H* H* calculation calculation process the relationship relationship between between TITS contact pressure pressure in the Model Model 05D5 is much more reasonable and follows the expected expected trend from the more detailed analysis.

detailed The Model F H* H* contact pressure results, using the old fit, are well within the range predicted predicted by by the more detailed detailed analysis in in section 6.2.5 and the additional work described described in this RAI response. See Figure RAI 4-10 below. This means that the old fit is appropriate Figure RA14-10 appropriate to use for the the 29

LLTR-SGMP-09-109 TR-SGMP-09-1 09 NP-Attachment NP-Attachment NOP and SLB conditions and the NOP condition in the Model Model F NOP Model 05 SG. The results of Model D5 of described in Reference using the fit described finite Reference 6-15 match the expected trend from a best case finite element model for the NOP and SLB conditions for the Model F SGs and NOP conditions for the the Model D5 SG.

Model 05 To further address the concern pressure may be lost at displacements concern that contact pressure displacements ranging between 1E-3 in and 1E-4 in, between in, the "Unit Cell" model is extensively Section 1.3 of this extensively discussed in Section this above..

response above 30 30

LTR-SGMP-09-109 LTR-SGMP-09-109 NP-Attachment NP-Attachment a.c,e a,c,e Figure RAI 4-9

- a,c,e a,c,e Figure RAI Figure 4-10 RAI 4-10 31 31

LTR-SGMP-09-109 LTR-SGMP-09-1 09 NP-Attachment NP-Attachment Calculation Basis for Contact Pressure 2.1 Calculation Pressure Reduction Reduction Factors Factors II Provide Provide the calculation calculationbasis basis for the upper upper and and lower lower curves provided provided in in Figure Figure RA14-2 RAI 4-2 I

Response

The original figure RAI4-2, referred to in the question, is reproduced reproduced here as RAI4-10 RA14-10 to provide provide the foundation for the question and the response. Note that the scale of the y-axis has been corrected corrected as discussed in the meeting on August 17, 2009.

a,c,e Figure RA14-10 RAI4-10 (original Figure RAI4-2)

The upper upper curve in the figure above is based based on the data from the following table:

32 32

LLTR-SGMP-09-109 NP-Attachment TR-SGMP-09-1 09 NP-Attachment Eccentricity (ADmax-Eccentricity (L1Dmax- Reduction in Contact Normalization Normalization Contact Pressure ADmin) (in)

L1Dmin) (in) Pressure (psi)(1)

Pressure (psi)(1) Basis Reduction Reduction (psi)

(psi) Factor(psi/psi) 0 0 0 2E-4 [ )) a,c,e aT,c,e psi 1200 1200 [ ] a,c,e a,c,e

] a,c,e psi a,c,e 4E-4 5E-4 r[ ]a~ce psi 1[ Ja,c,e

]a,c,e 5E-4 r ] a,c,e psi ] a,c,e 6E-4 ] a,c,e I a,c,e I

Notes: (1) 6E-4 [ 1[ Ja,c,e a,c,e:

(1) Contact Contact stress reductions reductions are based on the values on Table RAI4-3 RA14-3 Referring to Table RAI 4-3, the contact pressure for a round tube bore hole is calculated to be Referring to Table RAI 4-3, the contact pressure for a round tube bore hole is calculated to be I

[

I a,c,e psi (Ratio = 1.0). The contact pressure for a tube bore hole that results in a

] a,c,e psi (Ratio = 1.0). The contact pressure for a tube bore hole that results in a contact pressure pressure ratio reduction of (( ]a,c,e (Ratio =

t,c,e = [ ]a,c,e), which corresponds to an

]8,ce),

eccentricity of 2E-4 inch, eccentricity inch, is [ ]a,c,e psi. The absolute reduction

]a,c,e reduction in in contact pressure is is I[ )) a,c,e psi.

psi.

The total reduction in contact pressure pressure using the new model is approximately [ a,c,e psi (see

] a,c,e Figure Figure 6-69 of WCAP-17072-P).

WCAP-17072-P). To plot the absolute reduction in in contact pressure of I I] a,c,e psi for an eccentricity of 2E-4 on Figure RAI4-1 0, the value is normalized by the total a,c,e psi for an eccentricity of 2E-4 on Figure RAI4-10, the value is normalized by the total reduction reduction in contact pressure pressure of [ )) a,c,e a,c,e psi from the new method. This value represents a reduction reduction in in contact pressure of [ ]a,c,e.

]a,c,e.

Again, referring to Table RAI 4-3, the contact pressure for a round tube hole is calculated to be Again, referring to Table RAI 4-3, the contact pressure for a round tube hole is calculated to be I I a,c,e psi. The contact pressure for a tube bore hole that results in a contact pressure

[ ] a,c,e psi. The contact pressure for a tube bore hole that results in a contact pressure ratio reduction reduction of (( ]a,c,e (Ratio = ((

]a,c,e ] a,c,e),

ace), which corresponds corresponds to be eccentricity eccentricity of 4E-4 inch, inch, is [ ] ac,e a,c,e psi. The absolute absolute reduction reduction in contact pressure is [ I] a,c,e psi.

Again, the total reduction in contact pressure in contact pressure using using the new model the new model is approximately ((

is approximately a,c,e I] a,c,e psi (see Figure 6-69 of WCAP-17072-P).WCAP-17072-P). To plot the absolute absolute reduction in contact pressure of I[ I] a,c,e psi for an eccentricity of 4E-4 on Figure RAI4-10, the value is normalized by the a,c,e psi for an eccentricity of 4E-4 on Figure RAI4-10, the value is normalized by the total reduction in contact pressure of (( ] a,c,,

a,c,e psi from the new method. This value represents represents a reduction in contact pressure pressure of (( ] ac,e a,c,e.

The same calculation was completed completed for an eccentricity of 6E-4 in. The value for 5E-4 in is an interpolated value between interpolated between 4 E-4 in and 6E-4 in.

The bottom curve in the figure above is generated generated using the 33rd rd order polynomial polynomial fit. The results results are summarized in the following table:

33 33

L TR-SGMP-09-1 09 NP-Attachment LTR-SGMP-09-109 NP-Attachment eccentricity (in)

E, eccentricity (in) TITS Contact Contact Normalized Normalized Contact Pressure Reduction Reduction Pressure Pressure Reduction Reduction (psi) 6.36E-07 [ ))a~ce a,c,e

[ lace

] a,c,e 5.53E-05 J ] a,c,e lace [ J]a~ce a,c,e 3.16E-04 ] a,c,e

]a~c~e ))a,c,e a,c,e

[ [

5.69E-04 [ .))a~c~e a,c,e [ J]aa,c,e ce 9.07E-04 ] a,c,e

]a.c~e ))a.c.e a,c,e

[ [

rd 2.2 Conservatism Conservatism of 3 3 rd Order Polynomial Polynomial Fit from WCAP Reference 6-15 WCAP Reference 6-15 Provide Provide the basis model remains basis for why the I1D conservative.

remains conservative.

ho/e adjustment ADhole adjustment for contact pressure made contact pressure made usingusing the old I

Response

The key conclusions conclusions from the comparison of the Reference Reference 6-15 analysis, the WCAP results and the results of the square cell tubesheet model model are:

1.) The fit described 1.) Reference 6-15 of the H*

described in Reference conservative when applied H* WCAP reports is conservative applied to the NOP Nap condition in both the Model D5 05 and Model Model F SG. The fit tends to under-estimate the contact pressure during Nap NOP by by as much as as much as (( ]a,c,e psi

]a,c,e to ((

psi to Ia,c,e

]a,c,s psi) for the Model F SG and as much as [ ]a,c,e D5 SG ([([

]a,c,s % for the Model 05 ]a,c,e psi to

]a,c,s to

[I psi) (see Table RAI4-6).

]a,c,s psi)

]a,c,e RAI4-6).

2.) The fit described in Reference 2.) Reference 6-15 of the H* H* WCAP reports is comparable comparable when applied applied to the SLB condition in the Model F SG. The fit described described in the Model D5 05 White PaperPaper tends to over-estimate the contact pressure, by as much as [ ]a,c,s  %, during SLB

]a,c,e %,

([

([ ]a,c,e psi to ((

]a,c,s ]a,c,e psi) because

]a,c,s because the White Paper does not fully account account for the the change in tube bore diameter during the transient.

3.)

3.) The fit described Reference 6-15 of the H*

described in Reference H* WCAP reports significantly under-estimates under-estimates contact pressure, by as much as (( ]a,c,s the contact ]aC.6 %,%, during the D505 SLB condition (from

[.

]a,c,e psi

]a,c,s to ((

psi to ]a,c,e psi).

]a,c,s psi).

4.) The square cell tubesheet finite element element model model shows an increase increase in contact contact pressure when going from Nap NOP to SLB conditions in in both the 05 D5 and F SGs.

34

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-1 09 NP-Attachment 5.) Using the results from the square cell model to estimate the magnitude of the contact pressure reduction reduction from the change in in tube bore diameter diameter calculated using the 3D 30 finite finite element results from the lower lower SG tubesheet complex complex model show that the contact pressure pressure still increases increases when going from NOP to SLB conditions conditions inin both the Model F andand Model D5 SG.

Model 05 The results of this analysis show that NOP contact pressures pressures that define H* in the Model F and define H*

Model D5 Model 05 SG are conservative conservative and that a more realistic model of contact pressure pressure reduction reduction as a function of tube bore bore deformation deformation (including both dilation and eccentricity) eccentricity) would predict an increase in tube to tubesheet contact increase contact pressure at SLB conditions compared to NOP NOP conditions.

(See also Section 2.3) 2.3 SLB vs. NOP NOP Contact Contact Pressures Pressures Provide Provide an appropriate appropriatebasisbasis for demonstrating demonstratingthat thatjoints tighten during jOints tighten during a postulated postulated SLB event.

SLB event. WhyWhy is it acceptable acceptable to compare compare the contact pressures calculated contact pressures calculated using the original original model for NOP NOP to the contact contact pressures pressurescalculated calculatedusing using the new model for SLB SLB for the Model D5 SGs?

Response

RAI4-5 provides a summary of contact pressures Table RA14-5 pressures between the tube and the tubesheet for for various applied values of E-bar for the Model FF and Model D5 Model 05 SGs. Comparison of the the eccentricity values calculated using the unit cell model (see Table RAI4-5) with the eccentricity eccentricity eccentricity values values calculated from the 30 3D FEA model (see TableTable RAI4-1)

RAI4-1) shows that the eccentricities eccentricities from from both models models are comparable. ItIt is not reasonable reasonable to expect exact matches between matches of numbers between the two models, however, the order of magnitude of the calculated eccentricities eccentricities is the same.

structural models provide similar eccentricities, Given that the two structural eccentricities, the unit cell model model shows that for these eccentricities, eccentricities, positive positive contact pressure pressure exists between the tubes and the tubesheet for the entire range of displacements displacements considered. Further, the results show that the contact pressures at SLB conditions exceed those at NOP conditions (See Table RAI4-6). See also the the discussion in Section Section 2.4 below.

35 35

LLTR-SGMP-09-109 NP-Attachment TR-SGMP-09-109 NP-Attachment Conservatism of "Old" and "New" 2.4 Relative Conservatism "New" FitFit I lf both old and new models are I conservatism of the methods?

relative conservatism relative are conservative, conservative,is there methods?

an appropriate there an appropriate basis basis to show the

Response

As noted above in in Section 1.3 of this response, tube bore dilation is a more significant factor in in determining tube-to-tubesheet determining tube-to-tubesheet contact pressure at higher temperatures temperatures and the effect of eccentricity on contact pressure eccentricity pressure is reduced at higher temperatures. The methodology for addressing the effect of eccentricity addressing eccentricity on contact contact pressure pressure discussed discussed in in Reference Reference 6-15 and utilized in WCAP-17071-P, utilized in WCAP-17071-P, WCAP-17072-P, WCAP-17091-P WCAP-17091-P and WCAP-17092-P WCAP-17092-P reflects thisthis fact and it, it, therefore, provides acceptably acceptably accurate accurate contact pressure results at higher temperatures (Le.,

temperatures (i.e., for all conditions except the "colder" "colder" SLB condition).

condition). This includes NOP, SLB (higher (higher temperature, > 4000 F, and FLB, where appropriate).

> 400°F, appropriate).

Also, as noted in in Section Section 1.3 of this report, the effect of eccentricity eccentricity on contact pressure pressure loss is a more significant factor at the lower SLB temperatures for the Model D5 SG, but tube bore dilation due to temperature temperature and pressure needs to be considered (which was not addressed in in "new" method, a.k.a the White Paper method discussed in the "new" WCAP-17072-P or 17091-P).

in WCAP-17072-P 17091-P).

Moreover, the original 3rd order polynomial fit significantly over-predicts over-predicts contact pressure loss pressure loss during the "colder" "colder" Model Model D5 SLB transient (and Model 44F two loop plant SLB).

Therefore, a more more detailed detailed model for contact pressure pressure during a postulated SLB was developed.

developed.

Referring to Table RAI4-6, itit shows that contact pressure increases Referring increases during a SLB event

([

([

]a,c,e psi) relative to NOP ([

]a,c,e psi) relative to NOP ([

] ac,e psi) with primary and secondary side temperatures as

] a.c,e psi) with primary and secondary side temperatures as low as 212OF 212°F when comparingcomparing contact pressures for NOP conditions conditions for the unit cell to contact pressures pressures for SLB for the unit cell.

Again, referring to Table RAI4-6, RAI4-6, itit has has been shown when comparingcomparing contact pressures pressures for NOP NOP conditions for the unit cell to contact pressures conditions pressures for SLB for the unit cell for the Model F SG (higher temperature temperature SLB conditions), that contact pressure increases increases during aa postulated postulated SLB (from (( a,c,e psi at NOP to ((

] a,c,e ] a,c,e psi at SLB).

36

LLTR-SGMP-09-109 TR-SGMP-09-1 09 NP-Attachment NP-Attachment 3.0 Comparison of 3D FEA and Unit Cell Model Model Results Results The eccentricities eccentricitiesincluded included in Table Table RAI 4-4 appear appearlarger larger than anticipated.

anticipated. Need to confirm that positive positive contact contact pressure pressure exists around around the entire circumference entire circumference of the tube and state and state this this clearly clearly inin the response.

response.

Response

Comparison Comparison of the eccentricity eccentricity values calculated using the unit cell model model (see Table RAI4-5) eccentricity values calculated with the eccentricity calculated from the 3D FEA model (see Table RAI4-1) RAI4-1) shows that the eccentricities eccentricities from both models are comparable. ItIt is not reasonable reasonable to expectexpect exact matches of numbers between the two models, however, the order of magnitude of the the eccentricities eccentricities calculated calculated is the same. Given that the two structural models provide similar similar eccentricities, eccentricities, the unit cell model shows that for these eccentricities, positive contact pressure pressure exists between between the tubes and the tubesheet for the entire range of displacements displacements considered.

Further, the results show that the contact pressures pressures at SLB conditions exceed those at NOP NOP conditions.

4.0 Additional Background Information For Key Questions Background Information Questions and Issues Issues RAI#4 RAI#4 evolved evolved inin several stages, each stage building on the prior stage. ReferenceReference 10 provided additional questions additional questions to augment those that were provided by Reference Reference 5. Responses Responses were prepared prepared and were discussed discussed in in a telephone conference telephone conference on August 11, 11, 2009., During 2009. During this this telephone conference, additional questions questions were raised as identified identified in in the introduction introduction of this this document. The following are responses that were provided in Reference 10 that in response to Reference were discussed in in the August 11, 11, 2009 telephone conference.

conference. They are historical in nature and historical in are provided to complete the record of information provided in in response to the NRC request for additional information.

information.

Comparison of "Old and New" 4.1 Comparison New" Relationship Relationship for Reduction in Contact Pressure and and Eccentricity Eccentricity In Figure Figure 2 of the White Paper,Paper, add a plot for original originalrelationship relationshipbetween reductionsreductions in contact pressure contact pressure and and eccentricity eccentricity as given in Reference 6-15 in in the graph accompanying graph accompanying Table 6-3. Explain Table Explain why this original original relationship relationship remains conservative in light remains conservative light of the new relationship. Explain relationship. Explain the reasons reasonsfor the differences between the curves. curves.

In order to superimpose In superimpose the results of the "old" and "new" analyses analyses for reduction reduction in in contact pressure related to eccentricity, the data for the "old" method mList must be normalized normalized in in the same fashion that Figure 2 has been normalized. The plot of contact contact pressure reduction included in in 37

LLTR-SGMP-09-109 TR-SGMP-09-109 NP-Attachment NP-Attachment Figure 22 of the White Paper Figure represents the total reduction in contact pressure associated Paper represents associated with a eccentricity. The information given eccentricity. information from Table 6-3 represents represents the ratio of the contact pressure calculated at aa given eccentricity calculated eccentricity divided divided by the contact pressure calculated for a tubesheet tubesheet bore with no eccentricity. For the new analysis, the total reduction reduction in contact pressure for the the eccentricities eccentricities (OMAX OMIN) for (DMAx - DMIN) a range of up to [ inch is determined

]a,c,e inch is determined to be [

]a,c,e to be [ ]a,c,e

]a,c,e psi. For the old analysis, the total reduction in contact pressure for eccentricities eccentricities in the same range is calculated calculated to be [ ]a,c,e psi. The normalization

]a,c,e normalization basis is the same for both curves curves on the figure.

Figure RAI4-11, RAI4-11, showing showing the normalized normalized results as discussed discussed during the August 17, 2009 meeting, is provided below. (Figure RA14-11 RAI4-11 is the same as Figure RA14-10 RAI4-10 in Section 2.1 of this document, except that the values of the "Old Polynomial Results" have been corrected corrected on Figure Figure RA14-10 RAI4-10 by a factor factor of 2 as discussed in the August 17, 2009 meeting.) The curve curve labeled labeled "Old" Model Results Results is based on the data from Table RAI4-3 RA14-3 (Table 6-2 of Reference 15 of the WCAP report). The curve labeled "New" Model reproduces Figure 22 in the White Model reproduces White Paper (Reference 12). The curve labeled "D5 (Reference "05 SLB Polynomial Polynomial Fit" are the results when when thethe eccentricity data and ADhole eccentricity ,10hole for the Model D5 05 SLB condition are applied applied directly to the the polynomial fit, equation 6-8 in WCAP-17072-P and similar equation equation on page 6-85 in WCAP-17071-P.

WCAP-17071-P. The latter curve is based based on the maximum displacement displacement conditions at the top of the tubesheet for the Model D5. 05.

The curve labeled "Old Model Results" (top curve on Figure RAI4-1 1) is misleading relative to Figure RAI4-11) making an assessment assessment of the conservatism of the new new analysis method compared compared to the old old analysis method.

analysis method. UnlikeUnlike the new analysis method, which is only applied to the SLB case for the the Model D5 05 SGs, the old analysis method has not been applied as a linear function function asas represented represented in the figure as the uppermost curve (solid squares). In reality, the old data fit (top curve on Figure Figure RAI4-11),

RAI4-1 1), which is a 3rd order polynomial polynomial fit, when extrapolated extrapolated significantly significantly outside its supported outside supported data range (Le., (i.e., at temperatures temperatures either significantly significantly above or below 5000 F), provides 500°F), provides physically unrealistic unrealistic results as shown on Figure Figure RA14-11 RAI4-11 (bottom curve, A-symbols). The Model 05 D5 SLB condition puts the tubesheet at a nearly uniform temperature temperature of 3000 F, which is far outside of the range for which the eccentricity less than 300°F, relationship was eccentricity relationship was developed in Reference developed Reference 6-15 in the WCAP reports.

The original relationship remains conservative because itit predicts greater reduction conservative because reduction of tube to to tubesheet tubesheet contact pressure pressure than the new method method for all operating conditions. However, the the original relationship relationship is only valid when ADmi, ,10min and ,10max AlDmax are within [ ]a,c,a]a,c,e % and eccentricity eccentricity is within [ ]a,c,e inch to [ ]a,c,e inch range, (i.e.,

]a,c,e (Le., the basis of the original fit).

The maximum tube bore distortions occur at the top of the tubesheet. The results from applying distortions occur applying the old fit for the relationship relationship versus the new fit for the relationship relationship for the Model 05 D5 SLB tubesheet tubesheet displacements displacements and contact contact pressures pressures are shown in Table RAI4-7. The tube-to-tubesheet (TITS)

(T/TS) contact pressure pressure result due due to thermal expansion expansion of the tube and the pressure expansion of the tube including expansion including the effect of the crevice pressure distribution, distribution, is the same in the the both the "old" and "new""new" cases in the Table RA14-7 RAI4-7. .

38 38

LTR-SGMP-09-109 L TR-SGMP-09-1 09 NP-Attachment NP-Attaehment RAI4-7 Table RA14-7 Summary of Model D5 Summary 05 SLB Contact Pressure Results for for Different Eccentricity Eccentricity Fit Relationships Relationships Model 05D5 T/TS PCON Reduction TITS PeoN TITS PeoN T/TS PCON Condition Value Eccentricity Eccentricity Old New Old New New 1a,c,e SLB Avg Avg SLB Max Max SLB Min Min The results in Section 6.2.4 of WCAP-17071-P WCAP-17071-P and WCAP-17072-P WCAP-17072-P show that the average average expected tubesheet-tube-bore eccentricity is on the order of [

tubesheet-tube-bore eccentricity ]a,c,e inch. The results Ia,c,e in Table RAI4-7 show that the old method Table RA14-7 method of calculating the reduction reduction in contact pressure due due tubesheet-tube-bore eccentricity to tubesheet-tube-bore eccentricity and change change in diameter is conservative conservative for larger larger values of eccentricity and b.0 eccentricity AD (predicts greater greater decrease decrease in contact pressure) than the new fit. However, it is inappropriate inappropriate to use the old method at smaller values of eccentricity eccentricity and AD b.0 because it provides physically impossible results (see Table RAI4-7). For example, the "old" method predicts a larger larger decrease decrease in contact contact pressure for a smaller eccentricity eccentricity on the order of 10- 10-77 inch than for aa larger eccentricity eccentricity on the order 10-3 inch. The "new" order of 10-3 "new" method, method, by comparison, comparison, predicts aa slightly positive increase increase in contact eccentricity of 10-7 inch and a pressure for an eccentricity contact pressure large reduction reduction in contact pressure for an eccentricity of 10- 10-44 inch or greater, a a physically physically realistic result. The reason that the "old" method predicts such a different reduction in contact pressure for small values of eccentricity eccentricity is that these small eccentricity eccentricity values values are well outside outside the range of the data upon which the "old" relationship relationship was developed.

developed. However, when used within its intended range of eccentricities eccentricities and tubesheet bore displacement, displacement, the "old" methodmethod provides valid and conservative conservative results. The "new" methodmethod of calculating calculating the reduction in T/TS TITS contact contact pressure is linear and directly accommodates directly accommodates small calculated calculated values of eccentricity.

eccentricity. It is also clear from the results in Table RA14-7RAI4-7 that the results from the old method method when used in eccentricity range are highly conservative its supported eccentricity conservative compared compared to the "new" "new" method.

39 39

LTR-SGMP-09-109 NP-Attachment LTR-SGMP-09-109 NP-Attachment a,c,e RAI4-11 Figure RA14-11 Original RAI4-2 Discussed Original Figure RA14-2 Discussed at the August 17, 2009 Meeting Meeting 40 40

LLTR-SGMP-09-109 NP-Attachment TR-SGMP-09-1 09 NP-Attachment 4.2 Use of Both "Old" and "New" "New" Fit Fit When establishing establishing whether whether contact contact pressure pressure increases increases when going going from normal normal operating to steam operating steam line break conditions, line break conditions, how can can a valid and and conservative conservative comparison comparison be made if if the normal operating case normal operating case is based on the original is based original delta delta contact pressure contact pressure versus eccentricity eccentricity curve andand the SLB case case isis based based on the new curve?

Response

Response:

It is important to note than the new analysis method method is only used for the SLB condition condition for thethe Model D5 05 steam Comparison of contact steam generators. Comparison contact pressures between normal operating between the normal operating condition condition and the SLB condition is made made for the Model F steam generators generators in the H* fleet in in WCAP-17071-P WCAP-1 7071-P on a consistentconsistent basis.

ItIt is Westinghouse's engineering judgment Westinghouse's engineering judgment that the old methodology provides an accurate accurate determination of contact pressures during determination during normal operating operating conditions conditions and postulated accident accident conditions (FLB and SLB) when peak temperatures conditions temperatures range between between [ of and

]a,c,e OF

]a.c.e eccentricities eccentricities are betweenbetween (( ]a.c.e inch and ((

]a,c,e ]a.c.e inch and Dmax

]a,c,e Omax and Omin within Dmin are within

]a.c.e % of each

[I]a,c,e each other.

Application of the new method Application method to calculate eccentricities eccentricities and values of Dmax Omax and Omin Dmin that fall outside outside the above noted conservative results because the plane noted range provides conservative plane strain model upon upon which it based based over-estimates over-estimates the stiffness stiffness of the tube and tubesheet tubesheet structure structure leading leading toto lower contact pressure results as a function of eccentricity. The new method method also excluded excluded the the effect effect of temperature conservatively bounds the lower temperatures of the Model temperature and therefore, conservatively D5 SLB transient. The TITS 05 T/TS contact contact pressure pressure results during during SLB are still expected expected to bound bound thethe T/TS contact TITS contact pressure results during NOP because, even though the tube bore eccentricity eccentricity during SLB is generally greater during greater than that during NOP, the overall growth growth of the tube bore during NOP NOP is greatergreater than that during SLB. Larger magnitudes magnitudes of tube bore growth growth are directly directly related decreasing tube-tubesheet to decreasing tube-tubesheet contact contact pressure pressure regardless of the value of calculated calculated tube borebore eccentricity.

It is appropriate appropriate to compare the Model 05 D5 SLB contact pressure pressure results from the "new""new" method to the Model Model D5 05 NOP results from the "old" method because each condition method because condition uses the the appropriate fit to conservatively appropriate determine the reduction in T/TS conservatively determine TITS contact pressure due to tube tube bore eccentricity bore eccentricity and tube bore growth.

The sole purpose of the new methodologymethodology was to develop a more accurate accurate way of calculating calculating contact pressures during during a postulated postulated SLB for the Model 05 D5 steam steam generators.

generators. The The comparison comparison provided in Figure 6-83 of WCAP-17072-P WCAP-17072-P remains a valid comparison.

41

LLTR-SGMP-09-109 NP-Attachment TR-SGMP-09-1 09 NP-Attachment 5.0 Part A (Original RAI#4)

Reference 1, Page concluded that the tube Page 6-69: In Section 6.2.5.3, it is concluded diameter tube outside diameter and the tubesheet and tubesheet tube bore bore inside inside diameter maintaincontact diameter always maintain contact in the predicted predicted range of tubesheet range tubesheet displacements.

displacements. However, However, for tubes with through-wall cracks at through-wallcracks at the H*

H*

distance, distance, there there may be little or no net pressure pressureacting acting on the tube for some distance distance above H*. In Tables 6-18 6-18 and 6-19, the fourth fourth increment increment in the step that occurs two steps prior last step suggests prior to the last suggests thatthat there there may be no contact contact between the tube and tubesheet, over a portion tubesheet, circumference, for a distance portion of the circumference, distance above above H*. Is the conclusion conclusion in 6.2.5.3 6.2.5.3 valid valid for for the entire entire H*H* distance, distance,given the possibility possibility that that the tubes may contain contain through-wall through-wall cracks cracks at at that location?

location?

The following response to RAI#4 was included Reference 11.

included in Reference 11. The same response is included included here here to complete complete the record information provided record of information provided in regard to RAI#4 of References References 5, 6 and 7.

Response

The conclusions conclusions reached reached inin Section Section 6.2.5.3 of WCAP-17071-P are valid for the entire H* H*

distance because distance because of the following considerations:

1. The primary source of contact pressure pressure between between the tube and the tubesheet is differential thermal expansion expansion between between the tubes and the tubesheet. The analysis in specifically excludes the effect of thermal expansion Section 6.2.5.3 specifically expansion of the tube from the the analysis. The tubesheet is assumed to deform deform due to the combination of pressure and and thermal loads which produces produces the tube bore ovalization ovalization and leads to the displacements displacements applied in this model. Only the residual effects from installation are considered for the the tube in steps 1 through through 5. The tube internal pressure applied in these steps only simulates the hydraulic expansion pressure simUlates pressure to establish the initial conditions for thethe following step. The conditions conditions assumed for this study are not possible during during any operating operating condition in the steam generator but are conservative steam generator conservative relative to actual SG conditions. (Note: Residual Residual contact pressure pressure is not used used in the calculation of H* values H* values in Section 6. The residual effects of installation are included included in the results of Section Section 6.2.5.3 so that the sensitivity of aa strain hardened hardened tube to tubesheet tubesheet tube bore deformation deformation can be studied.)
2. Step 5 on Tables 6-18 and 6-19 is not representative of any condition in the steam generator because generator because itit assumes assumes that the tubesheet is at operating operating temperature with an applied applied primary-to-secondary primary-to-secondary pressure differential while the tubes remain at room temperature and are not pressurized.

temperature pressurized. That is why Steps 1 through 5 are described described asas "initializing" steps in the process. ItIt is physically impossible for these conditions conditions to occur simultaneously simultaneously in the same steam generator.

42

LTR-SGMP-09-109 LTR-SGMP-09-1 09 NP-Attachment NP-Attachment Because no pressure

3. Because pressure loading loading is applied to the tube in Step 5 of the analysis analysis discussed discussed inin section 6.2.5, the results presented in Tables 6-18 and 6-19 are applicable applicable regardless of whether, or not, aa through-wall crack exists at the H* H* location. representative location. The more representative case is Step 6 shown on Tables 6-18 and 6-19 in which tube internal pressure is internal pressure included. For that case, the potential point of zero contact pressure included. pressure is at an applied applied displacement a factor of 5 greater displacement greater than for Step 5, and far in excess excess of what is predicted for the actual tubesheet deformation. The factor of 5 difference in reasonably predicted in displacement to cause the contact pressure to reduce to zero more than required displacement adequately covers the postulated adequately reduction in crevice pressure due to a postulated potential local reduction circumferential separation circumferential separation at the location of H*. Recall also, that no thermal expansion expansion of the tube is considered in in this analysis.

ItIt is also noted noted that tables 6-18 and 6-19 are the resultsresultsofof a sensitivity study that is not intended to represent integrated calculation for H*.

represent the integrated H*. The integrated integrated H*

H* analysis is a complex process complex process that combines combines the effects of several types of loading and deformation deformation into an integrated estimate of the tube-to-tubesheet estimate appropriate to consider aa tube-to-tubesheet contact pressure. Therefore, it is not appropriate context of the greater analysis.

sensitivity study out of the context sensitivity integrated analysis analysis. The integrated presented in analysis presented in the complete complete Section 6 shows shows that for the combined case of the thermal effects, pressure effects, and tubesheet displacement tube-to-tubesheet contact pressure throughout the displacement there is tube-to-tubesheet the tubesheet.

It acknowledged that the cut end of a tube is radially less stiff than a tube that is radially It is acknowledged radially loaded at a point away from the tube end, and that the presumption loaded presumption of a tube sever at the H* H*

distance may represent the case of a tube end. The decreased distance decreased tube-end stiffness is referred to as "compliance." In In other other words, a tube that is loaded at the cut end provides less resistance to the load than a tube with equal load applied a distance removed from the tube-end. Thus, conceptually, a local "end effect" could be expected conceptually, expected to occur due to the increased compliance of increased compliance the tube-end.

tube-end.

calculation process for H*

The calculation H* shown shown in Figure 1-1 1-1 of the H* WCAP reports and discussed in H* WeAP several places in the report notes that an adjustment adjustment is made to the initial prediction of H* H* to account for the distributed account distributed crevice pressure referenced predicted H*

referenced to the predicted H* position. Thus, thethe greatest crevice crevice pressure is always located at the final value of H*. Increased tube compliance compliance cannot result in a higher higher local crevice pressure than is already included in the analysis because, crevice pressure because, at the point of sever, the primary side pressure pressure is the crevice crevice pressure.

increased tube compliance postulated that the increased It may be postulated compliance results in reduced reduced contact pressure because differential pressure across because the net differential tube-end, the current across the tube wall is zero. At the tube-end, current analysis already includes includes aa zero differential differential pressure due to the adjustment process for adjustment process distributed crevice pressure. Therefore, the net reduction in contact pressure pressure would be limited length of the local effect and would further depend to the axial length depend on the slope of the decrease decrease in in crevice pressure.

Model F and Model D5 For the Model 05 SGs, the bounding distance above the tube bounding value of isolation distance tube end is 0.6 inch based on classical solutions for the design of pressure vessels (Timoshenko).

43

LLTR-SGMP-09-109 NP-Attachment TR-SGMP-09-1 09 NP-Attachment isolation distance The isolation generically applicable distance is the generically separation distance from an applicable minimum separation applied load to a point of interest in order to safely safely assume that the load is in in the far field relative Specific structures and load cases may have different to the point of interest. Specific distances different isolation distances but the classical result by Timoshenko Timoshenko for a pressure vessel will conservatively conservatively bound any specific cases. For this length, the slope of the contact pressure pressure curve would decrease would have to decrease by aa factor factor of at least (( ]a,c,e

]a.c.e before the value of H* H* is affected affected by more more than [ ]ace inch.

]a.c.e inch. IfIf conservatively modeled as a center-loaded the tube is conservatively foundation compared center-loaded beam on an elastic foundation compared end-loaded beam on an elastic to an end-loaded elastic foundation, the resulting worst case change change in structural compliance compliance and the resulting contact pressure slope could be a factor of up to 2. Alternatively, similar analyses for the cross sections of curved curved beams suggest that the change change in compliance compliance of the structure structure could be as high as a factor factor of 6. Neither case approaches approaches the factor of (( 1]a.c.e ",c,e based on classical required based analysis to impact the value of H*; therefore, no classical pressure vessel analysis no adjustments to H*

additional adjustments H* are necessary address the potential end effects.

necessary to address 6,0 Response to RAI #4 6.0 Summary of the Response A summary of the response to the original RAI# RAI# 4 and additional questions related to RAI 4 are additional questions provided provided below:

adjustment to the value for H*

1. No additional adjustment
1. necessary to address the potential H* is necessary for end effects. This is because the greatest crevice crevice pressure pressure is always located at the final value of H*. At the H* H* distance, the current analysis already includes already includes aa zero pressure differential due to the adjustment process for the distributed crevice pressure. Therefore, the net reduction in in contact pressure pressure would be be limited to the axial length of the local effect and would further depend on the the slope of the decrease decrease in judged that the slope of the in crevice pressure. ItIt is judged the contact pressure curve would not decrease at aa rate such that the value of H* H*

would be affected.

affected.

dilation is a more significant factor in determining

2. Tube bore dilation tube-to-tubesheet determining tube-to-tubesheet pressure at higher contact pressure contact temperatures and the effect higher temperatures effect of eccentricity eccentricity on contact pressure pressure is reduced reduced at higher temperatures. The methodology methodology for addressing the the effect of eccentricity on contact pressure discussed Reference 6-15 and discussed in Reference utilized utilized in WCAP-17071-P, WCAP-17072-P, in WCAP-17071-P, WCAP-17091-P and WCAP-WCAP-17072-P, WCAP-17091-P 17092-P reflects this fact and, therefore, itit provides acceptably 17092-P accurate contact acceptably accurate pressure pressure results at higher temperatures (i.e., for all conditions temperatures (i.e., conditions except the "colder""colder" 0 F, SLB condition). This includes NOP, SLB (higher temperature, temperature, > 400 400°F, and FLB, where appropriate).

described in Reference 6-15 match

3. The results of using the fit described match the expected expected trend from a best case finite element model for the NOP and SLB conditions for the the Model F SGs and NOP conditions for the Model Model D5 05 SG.
4. The ~Os ADs from the 3D 30 FEA model are significantly less than the corresponding corresponding ADs from the unit cell model from the unloaded to the fully loaded

~Os loaded condition (i.e.,(i.e.,

44

LTR-SGMP-09-109 L TR-SGMP-09-1 09 NP-Attachment NP-Attachment from step 0 to step 9) for both NOP and SLB conditions. This leads to the the conclusion that the unit cell model displacement displacement results and contact pressure conservatively represent the reference 3D FEA model predictions conservatively model results.

5. The eccentricities eccentricities from the unit cell model are generally comparable to those from the 3D FEA model.model. A more exact comparison is difficult based based on the the available data; data; however, itit is clear that the actual range of eccentricities eccentricities from thethe 3D FEA model was adequately adequately addressed addressed by the unit cell model.

model.

6. Based on items 4) and 5) which demonstrate demonstrate the acceptability acceptability of the use of thethe unit cell model model for benchmarking benchmarking the 3-D FEA model, the method for calculating calculating the reduction in contact pressure pressure defined model, when adjusted defined by the unit cell model, for temperature temperature effects, shows that SLB contact contact pressure is increased increased relative to operating conditions for the Model 05 normal operating D5 steam generators.
7. ItIt has also been shown when comparing pressures for NOP conditions comparing contact pressures conditions for the unit cell to contact pressures for SLB for the unit cell for the Model F SG (higher temperature temperature SLB conditions), that contact pressurepressure increases increases during a postulated SLB.

postulated

8. Given that the two structural models provide similar eccentricities, eccentricities, the unit cell model model shows that for these eccentricities, positive contact pressure exists between between the tubes and the tubesheet tubesheet for the entire entire range of displacements displacements considered.

considered.

Based on the above, itit is concluded concluded that the NOP NOP contact pressures that define define H*H* in the Model F and Model 05 D5 SG are conservative conservative and that a more realistic model of contact pressure reduction reduction as a function of tube bore deformation (including both dilation and eccentricity) eccentricity) would predict predict positive contact pressure around the entire circumference contact pressure circumference of the tube and an increase increase inin tube to tubesheet tubesheet contact pressure compared to NOP conditions.

pressure at SLB conditions compared The conclusions conclusions reached in the response response to RAI#4 apply equally for the Model 44F and Model 51IF 51F SGs.

45

Vogtle Electric Generating Generating Plant Units 1 and 2 Response to Request Response Request for Additional Information Related Related to License License Amendment Amendment Request Request to Revise Technical Specification Specification (TS)

Sections Sections 5.5.9, "Steam Generator Program" and TS 5.6.10, "Steam Generator (SG) Program" "Steam Generator Inspection Report" for Permanent Generator Tube Inspection Criteria Permanent Alternate Repair Criteria Enclosure 3 Enclosure Westinghouse Westinghouse Electric Company Company LLC, CAW-09-2661, CAW-09-2661, "Application for Withholding Proprietary Information "Application Information from Public Public Disclosure" Disclosure"

e)

  • Westinghouse Westinghouse Westinghouse Electric Company Westinghouse Nuclear Services Services P.O. Box 355 355 Pittsburgh.

Pittsburgh, Pennsylvania 15230-0355 15230-0355 USA U.S. Nuclear Nuclear Regulatory Commission Directtel: (412)

(412)374-4643 374-4643 Document Control Desk Directfax:

Direct fax: (412) 374-3846 374-3846 Washington, DC 20555-0001 e-mail: greshaja@westinghouse.com greshaja@westinghouse.com Our ref.

ref: CAW CAW-09-2661 2661 August 27, 20092009 APPLICATION APPLICA nON FOR WITHHOLDING WITHHOLDING PROPRIETARY PROPRIETARY INFORMATION INFORMATION FROM DISCLOSURE FROM PUBLIC DISCLOSURE LTR-SGMP-09-109 P-Attachment, "Response

Subject:

LTR-SGMP-09-109 "Response to NRC Request for Additional Additional Information Information on H*; RAI # 4; Model Model F and Model Model D5 Steam Generators,"

Generators," dated August 2009 (Proprietary)

(Proprietary)

The proprietary proprietary information information for which withholding is being requested in the above-referenced above-referenced report is further identified in Affidavit CA CAW-09-2661 W 2661 signed by the owner of the proprietary information, proprietary information, Westinghouse Westinghouse Electric Company Company LLC. The affidavit, which accompanies accompanies this letter, sets forth the basis on which the information may be withheld from public disclosure disclosure by the Commission and addresses with specificity specificity the considerations considerations listed in paragraph paragraph (b)(4) of 10 CFR Section 2.390 of the Commission's Commission's regulations.

Accordingly, Accordingly, this letter authorizes authorizes the utilization of the accompanying affidavit by Southern Southern Nuclear Company.

Correspondence with respect to the proprietary Correspondence proprietary aspects of the application application for withholding withholding or the Westinghouse affidavit should reference reference this letter, CAW-09-2661, CAW-09-266 1, and should be addressed addressed to J. A. Gresham, Manager, Regulatory Regulatory Compliance Compliance and Plant Licensing, Westinghouse Electric Company Company LLC, P.O. Box 355, 355, Pittsburgh, Pennsylvania 15230-0355.

Pennsylvania 15230-0355.

Very truly y urs, J.A. Gresham, Manager J.A. Gresham, Manager Regulatory Regulatory Compliance Compliance and and Plant Plant Licensing Licensing Enclosures cc: G. Bacuta, Bacuta, (NRC OWFN 12E-1)

OWFN 12E-l)

CAW-09-2661 CA W-09-2661 bcc: Gresham(ECE A.Gresham bee: J.1.A. 4-7A) IL (ECE4-7A) IL R.R.Bastien, (NiveItes,Belgium) lL(Nivelles, Bastien, IL Belgium)

Brinkman,IL C.C.Brinkman, lL(Westinghouse ElectricCo.,

(WestinghouseElectric TwinbrookParkway, 12300Twinbrook Co.,12300 Suite330, Parkway,Suite MD 20852)

Rockville,MD 330,Rockville, 20852)

RCPL Administrative Aide (ECE 4-7A) IL (letter and affidavit RCPL Administrative Aide (ECE 4-7 A) 1L (letter and affidavit only) only)

G.G.W. Whiteman,Waltz W. Whiteman, WaltzMill Mill H.H. O. Lagally, WaltzMill

0. Lagally, Waltz Mill C.C.D.D.Cassino, WaltzMill Cassino,Waltz Mill Kandra, WaltzMill J.J.T.T.Kandra, Waltz Mill Robinson,ECE M.Robinson, J.J.M. ECE557A 557A

CAW-09-2661 CAW 2661 AFFIDAVIT COMMONWEALTH OF PENNSYLVANIA:

COMMONWEALTH PENNSYLVANIA:

ss ss COUNTY OF ALLEGHENY:

Before me, the undersigned undersigned authority, personally appeared J. A. Gresham, who, being by me duly personally appeared sworn according to law, deposes and says that he is authorized to execute execute this Affidavit on behalf of of Westinghouse Westinghouse Electric Company LLC (Westinghouse), (Westinghouse), and that the averments averments offact of fact set forth in this Affidavit are true and correct to the best of his knowledge, knowledge, information, and belief:

I J. A. AGresham, resham, Manager Manager Regulatory Compliance Regulatory Compliance and Plant Licensing Licensing Sworn to and subscribed before me 27hth day of August, 2009 this 27 Notary Public COMMONWEALTH COMMONWEALTH OF OF PENNSYLVANIA PENNSYLVANIA Notailsew NoIarJaJ Seal Sha.ml L Marle, Sharon Madde, Notary pubi Notary Public Monroeville Bora, Allegheny County MmnMnsylei Boro, Allsocony CouNtyaI Cori1mIssIOA Expires My Coormmslson Jan. 29, Boras Jan. 2011 29,2011 Member, Pennsylvania Association Member, Pennsylvania of NotarIes AssocIation of Notariles

CAW-09-2661 CAW-09-2661 (1)

(I) I am Manager, Regulatory Regulatory Compliance Compliance and Plant Licensing, in Nuclear Nuclear Services, Westinghouse Westinghouse (Westinghouse), and as such, I have been specifically Electric Company LLC (Westinghouse), specifically delegated delegated the function of reviewing the proprietary proprietary information sought to be withheld from public disclosure disclosure in connection connection with nuclear power plant licensing licensing and rule making proceedings, and am authorized to apply for its withholding on behalf of Westinghouse.

Westinghouse.

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(2) 1I am making this Affidavit in conformance conformance with the provisions of 10 CFR Section 2.390 of the Commission's regulations Commission's regulations and in conjunction "Application for conjunction with the Westinghouse "Application Withholding" accompanying this Affidavit.

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(3) I have personal knowledge knowledge of the criteria and procedures procedures utilized by Westinghouse Westinghouse in designating information information as a trade secret, privileged or as confidential commercial information, commercial or financial information.

(4)

(4) Pursuant to the provisions of paragraph (b)(4)(b)(4) of Section Section 2.390 of the Commission's Commission's regulations, the following is furnished for consideration consideration by the Commission in determining whether whether the information information sought to be withheld from public disclosure disclosure should be withheld.

(i) The information information sought to be withheld from public disclosure is owned and has been held in confidence confidence by Westinghouse.

(ii) The information information is ofa of a type customarily held in confidence confidence by Westinghouse Westinghouse and not customarily customarily disclosed to the public. Westinghouse Westinghouse has a rational basis for determining determining the types of information information customarily customarily held in confidence confidence by it and, in that connection, utilizes a system to determine when and whether to hold certain certain types of information in confidence.

confidence. The application of that system and the substance substance of that system constitute Westinghouse Westinghouse policy and provide provide the rational rational basis required.

Under that system, information is held in confidence confidence if it falls in one or more of several types, the release of which might result in the loss of an existing or potential potential competitive competitive advantage, as follows:

(a) The information reveals the distinguishing distinguishing aspects of a process process (or component, structure, tool, method, etc.)

etc.) where prevention of its use by any of of

CAW-09-2661 CAW 2661 Westinghouse's competitors without license from Westinghouse constitutes a Westinghouse's competitive economic economic advantage over other companies.

(b) It consists of supporting data, including test data, relative relative to a process (or (or component, structure, tool, method, etc.), the application of which data secures compQnent, secures a optimization or improved competitive economic advantage, e.g., by optimization improved marketability.

marketability .

(c) Its use by a competitor would reduce his expenditure of resources resources or improve his competitive competitive position in the design, manufacture, shipment, installation, assurance of quality, or licensing a similar product.

(d) It reveals cost or price information, information, production production capacities, budget levels, oror commercial strategies of Westinghouse, its customers or suppliers.

commercial (e)

(e) It reveals aspects aspects of past, present, or future Westinghouse Westinghouse or customer funded development plans and programs of potential development commercial value to Westinghouse.

potential commercial (f) It contains patentable patentable ideas, for which patent protection may be desirable.

There are sound policy reasons behind the Westinghouse Westinghouse system which include the following:

(a) The use of such information by Westinghouse Westinghouse gives Westinghouse Westinghouse a competitive competitive advantage over its competitors. It is, therefore, advantage therefore, withheld from disclosure disclosure to protect the Westinghouse competitive competitive position.

(b) It is information information that is marketable marketable in many ways. The extent to which such information information is available available to competitors diminishes the Westinghouse ability to sell products products and services services involving the use of the information.

(c) Use by our competitor would put Westinghouse Westinghouse at a competitive competitive disadvantage disadvantage by reducing his expenditure of resources resources at our expense.

expense.

CAW-09-2661 CA W-09-2661 (d)

(d) information pertinent Each component of proprietary information pertinent to a particular particular competitive competitive advantage is potentially as valuable as the total competitive advantage competitive advantage.

advantage. IfIf competitors acquire acquire components of proprietary proprietary information, any one component information, anyone component may be the key to the entire puzzle, puzzle, thereby depriving Westinghouse Westinghouse of a competitive advantage.

competitive advantage.

(e)

(e) Unrestricted Unrestricted disclosure disclosure would jeopardize jeopardize the position of prominence prominence of of Westinghouse in the world market, and thereby thereby give a market advantage to the competition of those countries.

(f) The Westinghouse capacity capacity to invest corporate assets in research and development development depends depends upon the success in obtaining and maintaining maintaining a competitive advantage.

competitive (iii)

(iii) information is being transmitted to the Commission in confidence The information confidence and, under the provisions of 10 CFR Section 2.390, it is to be received in confidence confidence by the Commission.

(iv)

(iv) The information sought to be protected is not available in public sources or available available information has not been been previously employed in the samesame original manner or method to the best of our knowledge and belief.

belief.

(v) The proprietary proprietary information information sought to be withheld in this submittal is that which is is appropriately marked in LTR-SGMP-09-109 LTR-SGMP-09-1 09 P-Attachment, "Response to NRC Request P-Attachment, "Response Request for Additional Additional Information Information on H*; RAI # 4; Model F and Model D5 Steam Generators,"

Generators,"

dated August 2009 (Proprietary), for submittal submittal to the Commission, Commission, being transmitted by Company letter and Application for Withholding Proprietary Southern Nuclear Company Proprietary Information from Public Information Public Disclosure to the Document Control Desk. The proprietary proprietary information as submitted submitted for use by Westinghouse for Vogtle Units 1 and 2 is expected to be applicable to other licensee licensee submittals in support support of implementing an alternate repair repair criterion, called called H*, that does not require an eddy current inspection inspection and plugging of of steam steam generator generator tubes below a certain certain distance from the top of the tubesheet.

This information information is part of that which will enable enable Westinghouse to: to:

CAW 2661 CAW-09-2661 (a) Provide documentation documentation of the analyses, methods, and testing which support the implementation implementation of an alternate repair criterion, criterion, designated as H*, for a portion ofof the tubes within the tubesheet of the.Vogtle Units 11 and 2 steam oftheVogtle steam generators.

generators.

(b)

(b) Assist the customer customer in obtaining NRC approval of the Technical Specification Specification changes associated with the alternate repair repair criterion.

Further this information has substantial commercial value as follows:

substantial commercial (a) Westinghouse plans plans to sell the use of similar information information to its customers customers for the purposes of meeting NRC requirements requirements for licensing licensing documentation.

(b) Westinghouse can sell support and defense of the technology to its customers in the licensing process.

Public disclosure of this proprietary proprietary information information is likely to cause cause substantial harm to the competitive competitive position of Westinghouse because it would enhance enhance the ability of ability of competitors to provide competitors provide similar calculation, calculation, evaluation evaluation and licensing defense services for commercial power reactors commercial reactors without commensurate commensurate expenses. Also, public disclosure of of the information would enable others to use the information to meet NRC requirements for documentation without purchasing licensing documentation purchasing the right to use the information.

The development of the technology described in part by the information is the result of of applying the results of many years of experience experience in an intensive Westinghouse effort and the expenditure expenditure of a considerable considerable sum of money.

In order for competitors Westinghouse to duplicate competitors of Westinghouse duplicate this information, similar technical programs would have to be performed performed and a significant manpower effort, having the requisite requisite talent and experience, experience, would have to be expended.

Further the deponent deponent sayeth not.

CAW-09-2661 CA W-09-2661 PROPRIETARY INFORMATION PROPRIETARY INFORMATION NOTICE Transmitted Transmitted herewith are proprietary proprietary and/or non-proprietary non-proprietary versions versions of documents furnished to the NRC in connection with requests for generic and/or plant-specific plant-specific review and approval.

In order to conform conform to the requirements requirements of 10 CFR 2.390 ofthe of the Commission's regulations concerning the protection of proprietary concerning proprietary information so submitted to the NRC, the information information which is proprietary proprietary in the proprietary proprietary versions is contained within brackets, and where the proprietary information information has been deleted in the non-proprietary non-proprietary versions, only the brackets brackets remain remain (the information information that was contained within the brackets brackets in the proprietary versions having been deleted). The justification justification for claiming the information so designated as proprietary proprietary is indicated in both versions by means of lower case letters (a) through (f) located as a superscript oflower superscript immediately following the brackets enclosing each item of information being identified identified as proprietary proprietary or in the margin opposite such information. These lower case letters refer to the types of information information Westinghouse customarily holds in confidence confidence identified identified in Sections Sections (4)(ii)(a) through (4)(ii)(f) of the affidavit accompanying this transmittal pursuant to 10 CFR 2.390(b)(1).

affidavit accompanying 2.390(b)(1).

COPYRIGHT COPYRIGHT NOTICE The reports transmitted herewith each bear a Westinghouse Westinghouse copyright copyright notice. The NRC is permitted to make the number of copies of the information information contained in these reports which are contained necessary for its internal internal use in connection connection with generic and plant-specific plant-specific reviews and approvals as well as the issuance, denial, amendment, transfer, renewal, modification, modification, suspension, revocation, revocation, or violation of a license, permit, pennit, order, or regulation regulation subject subject to the requirements requirements of 1010 CFR 2.390 regarding restrictions regarding restrictions on public disclosure to the extent such information infonnation has been identified as proprietary proprietary by Westinghouse, copyright copyright protection notwithstanding. With respect to the non-proprietary the non-proprietary versions versions of these reports, the NRC is permitted to make the number of copies beyond those necessary necessary for its internal use which are necessary necessary in order order to have one copy available for public viewing in the appropriate docket files in the public document document room in Washington, Washington, DC and in local public document rooms as may be required by NRC regulations if the number of copies submitted is insufficient insufficient for this purpose. Copies made by the NRC must include the copyright copyright notice in all instances and the proprietary proprietary notice if the original was identified identified as proprietary.

proprietary.

CAW-09-2661 CA W-09-2661 Southern Southern Nuclear Nuclear Company Letter for Transmittal to the NRC paragraphs should be included in your letter to the NRC:

The following paragraphs Enclosed Enclosed are:

of LTR-SGMP-09-109

1. 11 copy ofLTR-SGMP-09-1
1. 09 P-Attachment, "Response to NRC Request for Additional P-Attachment, "Response Information on H*; RAI # 4; Model F and Model D5 Information Generators," dated August 2009 05 Steam Generators,"

(proprietary).

(proprietary).

2. 11 copy of LTR-SGMP-09-109 LTR-SGMP-09-1 09 NP-Attachment, "Response to NRC Request for Additional NP-Attachment, "Response Model F and Model 05 Information on H*; RAI # 4; Model Information Generators," dated August 2009 D5 Steam Generators,"

(non-proprietary).

(non-proprietary).

CAW-09-2661 with accompanying authorization letter CAW-09-2661 Also enclosed is Westinghouse authorization accompanying affidavit, Information Notice, and Copyright Notice.

Proprietary Information As Item I1 contains information proprietary to Westinghouse Electric Company information proprietary Company LLC, it is supported by an affidavit signed by Westinghouse, the owner of the information. The affidavitaffidavit disclosure by the sets forth the basis on which the information may be withheld from public disclosure Commission and addresses with specificity considerations listed in paragraph (b)(4) of specificity the considerations of Section 2.390 of the Commission's ofthe Commission's regulations.

information which is proprietary Accordingly, it is respectfully requested that the information to proprietary to disclosure in accordance Westinghouse be withheld from public disclosure Westinghouse accordance with 10 CFR Section 2.390 of of Commission's regulations.

the Commission's regulations.

Correspondence with respect to the copyright Correspondence aspects of the items listed above or copyright or proprietary aspects Westinghouse affidavit should reference CAW-09-2661 the supporting Westinghouse addressed CAW-09-2661 and should be addressed Gresham, Manager, to J. A. Gresham, Manager, Regulatory Compliance and Plant Licensing, Westinghouse Regulatory Compliance Electric Westinghouse Electric Company LLC, P.O. Box 355, 355, Pittsburgh, Pennsylvania 15230-0355.

Pittsburgh, Pennsylvania 15230-0355.

!i