ML082490573

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July 2008 Evidentiary Hearing - Applicant Exhibit E2-25-VY, Calculation VY-19Q-301r0
ML082490573
Person / Time
Site: Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date: 01/29/2008
From: Chintapalli A, Weitze W
Structural Integrity Associates
To:
NRC/SECY/RAS
SECY RAS
References
06-849-03-LR, 10163217, 50-271-LR, Entergy-Applicant-E2-25-VY, RAS M-288 VY-19Q-301
Download: ML082490573 (18)
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4 UcýS Structural Integrity Associates, Inc.

FHe No.: VY-19Q-301 CALCULATION PACKAGE Project No.: VY-19Q PROJECT NAME:

Provide VY Support for Questions Related to Environmental Fatigue Analyses CONTRACT NO.:

10163217 CLIENT:

PLANT-Entergy Nuclear Operations, Inc.

Vermont Yankee CALCULATION TITLE:

Design Inputs and Methodology for ASME Code Confirmatory Fatigue Usage Analysis of Reactor Feedwater Nozzle Document Affected Project Manager Preparer(s) &

Revision Pages Revision Description Approval Checker(s)

Signature & Date Signatures & Date 0

1-18 Original Issue F-,

Computer Files

._.i WF Weitze S

1//2008 WFW 01/29/2008 A. Chintapalli AC 01/2Y2008 U-.6 NUMC REGI ILATORY COMMISSION DocketNo. SO-v)J OfficialExhibitNo. E'z-z.S-V OFFERED by" lcant/ce e tervenor_............

(DENTM NRC Staff Other ___________

IA,IIZaw 0'7 it 13 ness/Pane ijl ACjO~mTaIO ITE REJECTED WITHDRAWN potv/i i

I t_

DOCKETED USNRC August 12, 2008 (11:00am)

OFFICE OF SECRETARY RULEMAKINGS AND ADJUDICATIONS STAFF Page 1 of 18 F0306-0IRO

&Aw 6

W--03

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Table of Contents 1.0 O B JE C T IV E.................................................................................................................................

3 2.0 METHODOLOGY....................................................................................................

3 3.0 ASSUMPTIONS/DESIGN INPUTS.......................................................................................

4 4.0 C A L C U L A T IO N S......................................................................................................................

13 5.0 RESULTS OF ANALYSIS..................................................................................................

17 6.0 R E F E R E N C E S...........................................................................................................................

18 List of Tables T ab le 1: T ran sien ts....................................................................................................................

........... 5 T able 2: Properties of L iquid W ater.....................................................................................................

8 Table 3: Properties of Saturated Steam...........................................................................................

8 Table 4: Forced Flow and Natural Circulation Heat Transfer Coefficients; Btu/hr-ft2 -°F.............. 8 Table 5: Temperature-Dependent Material Properties................................................................

10 Table 6: Condensation Heat Transfer Coefficients, Btu/hr-ft2 -°F...............................................

13 Table 7: Membrane Plus Bending Stresses Due to Piping Loads................................................

14 List of Figures Figure 1: Nozzle and Vessel Wall Thermal and Heat Transfer Boundaries....................................

9 Figure 2: Safe End Linearization Path..........................................................

11 Figure 3: Nozzle Comer Linearization Path..........................

............................................................ 11 Figure 4: Coordinate System for Forces and Moments................................................................. 14 Figure 5: Reducer Geometry Parameters.......................................

15 Figure 6: FW Nozzle Safe End Geometry...................................................................................

16 File No.: VY-19Q-301 Page 2 of 18 Revision: 0 F0306-O1RO

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1.0 OBJECTIVE The objective of this calculation package is to establish the design inputs and methodology to be used for an ASME Code,Section III fatigue usage calculation of the reactor pressure vessel (RPV) feedwater (FW) nozzle at Vermont Yankee Nuclear Power Station (VYNPS).

2.0 METHODOLOGY A detailed fatigue usage analysis of the FW nozzle will be performed using the methodology of Subarticle NB-3200 of Section III of the ASME' Code [1]. The analysis will be used as a confirmatory, analysis for comparison with a previous fatigue usage analysis that was done using simplified methods. Therefore, only the fatigue portion of the ASME Code methodology will be used, and the analysis will be a fatigue assessment only, and not a complete ASME Code analysis.

Finite element analysis will be performed using a previously-developed axisymmetric finite element model (FEM) of the FW nozzle. Thermal transient analysis will be performed using the FEM for each defined transient. Concurrent with the thermal transients are pressure and piping interface loads; for these loads, unit load analyses (finite element analysis for pressure, and manual calculations for piping loads) will be performed. The stresses from these analyses will be scaled appropriately based on the magnitude of the pressure and piping loads during each thermal transient, and combined with stresses from the thermal transients. Additional scaling of pressure stresses will be performed to account for nozzle comer contour effects (i.e., the effects of approximating the nozzle-to-RPV intersection of two cylinders with an axisymmetric model). Other stress concentration factors (SCFs) will be applied as appropriate..

All six components of the stress tensor will be used for stress calculations. The stress components for the non-axisymmetric loads (shear and moment piping loads) can have opposite signs depending upon which' side of the nozzle is being examined. Therefore, when combining stress components from these loads with stress components from thermal transients and other loads, the signs of the stress components will be adjusted to maximize the magnitude of the stress component ranges.

The fatigue analysis will be performed at previously-examined locations for direct comparison of results. Stresses will be linearized at these locations. The linearized primary plus secondary membrane plus bending stress will be used to determine the value of K, to be Used in the simplified elastic-plastic analysis in accordance with ASME Code NB-3200"methodology. Environmental fatigue multipliers will be applied in accordance with NUREG/CR-6583 [15].

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3.0 ASSUMPTIONS/DESIGN INPUTS 3.1 Assumptions 3.1.1 Power uprate effects are considered as being applied to the entire period of operation. The higher pressures, flows, and temperatures at uprate conditions are used in determining and applying heat transfer coefficients [3, Section 3.2] [2, Section 3.1].

3.1.2 The Boltup transient [2, Tables 1 and 2] analysis does not affect the FW nozzle and is therefore excluded from the transients analyzed.

3.1.3 Where the flow rates in the thermal cycle diagram are at a value not calculated in Table 2, the next highest flow rate heat transfer coefficient will be used. This results in a higher heat transfer coefficient and is therefore conservative.

3.1.4 The effect of non-uniform geometries is judged to be insignificantforflow inside the safe end, because of the smooth transition and small geometry changes as shown in Figure 6. The smaller inner diameter (9.669") at the safe end was used to calculate heat transfer coefficients, resulting in a higher flow velocity and therefore conservative values.

3.1.5 The annulus leakage flow rate used is 31 GPMfor EPU conditions [3, Section 3.2].

3.1.6 Density and Poisson's ratio used in the FEMare assumed typical values of p = 0.283 lb/in3 and 0.3, respectively.

3.1.7 For purposes of linearizing stress at the nozzle corner, the effect of the cladding is conservatively neglected.

3.1.8 Stress components due to piping loads are scaled assuming no stress occurs at an ambient temperature of 70'F and the full values are reached at reactor design temperature, 5757F, as was done in the previous analysis [2, Section 3.4].

3.2 ASME Code Edition The analysis will be performed in a manner consistent with the fatigue usage rules in NB-3200 of Section III of the ASME Code; the 1998 Edition with Addenda through 2000 [1] will be used, for consistency with the previous analysis [2].

3.3 Transients Previously developed thermal and pressure transients [2, Section 3.1 and Tables 1 and 2] are used for this analysis. The transients to be evaluated are shown in Table 1. For each transient, the time, nozzle fluid temperature (Tnoz), RPV pressure, percent FW flow rate, and number of cycles are included. In some cases, flow rates and Tnoz values from the nozzle thermal cycle diagram [10,, p. 3] are used to reduce excess conservatism. Note that the only difference between the nozzle corner and the safe end transients in the referenced document is the length of the steady state time increment used at the end of the transients. These steady state periods are not included in Table 1; the analyst will use a value greater than or equal to the largest steady time increment from the referenced document.

At the inside surface of the RPV, the Region A temperature from the reactor thermal cycle diagram

[10, Attachment 1, p. 2] shall be applied. Table 1 also includes these values as TRPV.

File No.: VY-19Q-301 Page 4 of 18 Revision: 0 F0306-O1RO

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Table 1: Transients

Time, FW Transient sec Tn... OF TRPV, OF P, psig Flow, %

Cycles

1. Boltup 0

70 70 0

0%

123

2. Design Hydrotest 0

70 70 0

0%

120 1080 100 100 0

0%

1680 100 100 1100 0%

5280 100 100 1100 0%

5880 100 100 50 0%

3. Startup 0

100 100 50 0%

300 16164 549 549 1010 0%

4. Turbine Roll and 0

549 549 1010 0%

300 Increased to Rated 1

100 549 1010 25%*

Power 1801 100 549 1010 25%*

1802 260 549 1010 25%*

3602 392 549 1010 100%

5. Daily Reduction 0

392 549 1010 100%

10,000 75% Power 900 310 549 1010 100%*

2700 310 549 1010 100%*

3600 392 549 1010 100%

6. Weekly Reduction 0

392 549 1010 100%

2,000 50% Power 1800 280 549 1010 100%*

3600 280 549 1010 100%*

5400 392 549 1010 100%

9. Turbine Trip at 0

392 549 1010 100%

10 25% Power 1800 265 549 1010 100%

1980 265 549 101'0 25%*

2340 90 549 1010 25%*

2520 90 549 10o0 25%*

3420 265 549 1010 25%*

3600 265 549 1010 100%

5400 392 549 1010 100%

10. FW Heater 0

392 549 1010 100%

70 Bypass 90 265 549 1010 100%

1890 265 549 1010 100%

2070 392 549 1010 100%

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Transient

11. Loss of FW Pumps
Time, sec 0

1 3.5 4.5 13.5 184.5 1564.5 1565.5 2165.5 2166.5 2346.5 5406.5 5407.5 6727.5 6728.5 7148.5 7448.5 11048.5 16411.5 16412.5 18212.5 18213.5 20013.5 20014.5 21814.5 Tnoz, OF 392 565 565 50 50 50 440 565 565 50 50 440 549 565 50 50 300 400 549 549 549 100 100 260 392 TRPV, OF 549 565 565 565 565 565.

565 565 565 565 532 549 549 565 565 502 502 400 549 549 549 549 549 549 549 P, psig 1010 1010 1190 1184.5 1135 1135 1135 1135 1135 1135 885 1055 1055 1135 1135 675 675 232 885 1010 1010 1010 1010 1010 1010 FW Flow, %

100%

0%

0%

40%

40%

40%

0%

.0%

0%

40%*

40%*

0%

0%

0%

25%*

25%*

0%

0%

0%

0%

0%

25%*

25%*

25%*

100%

Cycles 10 12/13/15. Turbine

0.

392 549 1010 100%

289 Generator Trip, 10 392 565/600**

1135/1375**

100%

Reactor Overpressure, 15 392 565/600**

1135/1375**

100%

Other SCRAMs 30 392 539 940 100%

90 275 539 940 25%*

990 100 539 940 25%*

2790 100 539 940 25%*

2791 260 539 940 100%

3210 291 549 1010 100%

4591 392 549 1010 100%

14. SRV Blowdown 0

392 549 1010 100%

1 60 275 531.6 885 100%

960 100 365 50 25%*

19. Reduction to 0%.

0 392 549 1010 1000%

300 Power 1800 265 549

1010, 25%*
20. Hot Standby 0

265 549 1010 25%*

300 (Heatup Portion) 1 440 549 1010 0%

3925 549 549 1010 0%

20A. Hot Standby 0

549 549 1010 0%

300 (FW Injection Portion) 1 100 549 1010 25%

181 100 549 1010 25%

241 290 549 1010 0%

451 549 549 1010 25%

21-23. Shutdown 0

549 549 1010.

25%*

300 6264 375 375 50 25%*

6864 330 330 50 25%*

15144 100 100 50 0%

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Time, FW Transient sec T... OF TRPV, OF P, psig Flow, %

Cycles

24. Hydrostatic Test 0

100 100 50 0%

1 600 100 100 1563 0%

1200 100 100 1563 0%

1800 100 100 50 0%

25. Unbolt 0

100 100 0

0%

123 1080 70 70 0

0%

  • Flow rate is conservatively rounded up to one of the three flow rates considered (25%, 40%, 100%).
    • The second value applies for one cycle; the first value applies for the rest of the cycles.

3.4 Heat Transfer Coefficients, Condensation When steam floods a relatively cold component, the steam condenses on the component surface.

Holman [5, p. 413] gives the following equation for average heat transfer coefficient:

h = 0.555 {p(p - pv)gk3h'fg/[ýtD(Tg - Tw)]} "'

, where p = mass density of liquid, Pv = mass density of vapor, g = acceleration of gravity, k = conductivity of liquid at average temperature, h'fg hfg + 0.68c(Tg - Tw),

hfg = heat of condensation at vapor temperature, c = specific heat of liquid at average temperature, Tg = saturated vapor temperature = Tfinal, Tw =pipe inner wall temperature = Tinitial,

.= viscosity of liquid at average temperature D = inner diameter of pipe The portion of the equation inside the brackets, p(p - pv)gk 3h'fg/[ptD(Tg - Tw)], has the following units:

(ft )2 (seC2)

(Btu)3 (Btu)

(hr-ft-°F)3," (-bm (ft-hr) 1bf)fi

) 4 (OF)

(BtU4)

(ft 6) see2 )

(hti-ft--OF3)

(ft-hf)

(OF)

(36002 seel)

(hr) 12960000 Btu4 hr4_ft'_OF 4

After taking the fourth root, this becomes 60 Btu/hr-ft2-°F. Steam properties are interpolated at Tg, and water properties are interpolated at Tf, which is taken as the average of Tg and T,. Then, h'fg and heat transfer coefficient h are calculated for each set of steam properties, water properties, Tg and Tw.

Tables 2 and 3 list selected properties of liquid water [ 12, Table 1-8] and saturated steam [13],

respectively.

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Table 2: Properties of Liquid Water T, OF 300 400 500 600 P,

Ibm/fte 57.3 53.6 49.0 42.4 C,

Btu/Ibm-OF 1.03 1.08 1.19 1.51 119 Ibm/ft-hr 0.468 0.335 0.252 0.208 v, ft/sec 2.27E-06 1.74E-06 1.43E-06 1.37E-06 k,

Btu/hr-ft-OF 0.395 0.382 0.349 0.293 Table 3: Properties of Saturated Steam T1, -F v,, ft3/lbm, hf2, Btu/lbm 545 0.4449

.649.6 550 0.4249 641.6 565 0.3703 616.4 3.5 Heat Transfer Coefficients, Forced Flow and Natural Circulation' Table 4 summarizes the force flow and natural circulation heat transfer coefficients to be used in the analysis [3, Section 3.2.1]. For each flow rate, values are takenat 300'F as in the previous analysis.

These values are within 11% of the maximum values for a given flow rate, and are more than 30%

greater than the minimum values for a given flow rate [3, Table 4] [4, Tables 4 and 5]. Therefore, the use of heat transfer coefficients at 300'F is bounding for the most severe transients, which occur at a wide range of temperatures. Figure 1 illustrates the heat transfer coefficient regions [4, Figure 6].

Table 4: Forced Flow and Natural Circulation Heat Transfer Coefficients, Btu/hr!ft 2-°F 0% flow, Region 100% flow 40% flow 25% flow water 1

3705 1780 1222 144 2

3 1489 743 504 109 4

5 177 89 60 12 6

7 864 864 864 864 8

0.2 0.2 0.2 0.2

  • Linearly transition between the values for the adjacent regions.

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R!gi0n 7 Region 8

-F Region I C=

Region 4 Region 5 A B8C 0E Region 6 Notes: Point A:

Point B:

Point C:

Point D:

Point E:

Point F:

End of thermal sleeve = Node 204 - 0.25" from feedwater inlet side of thermal sleeve flat.

Beginning of annulus = Node 252.

Beginning of thermal sleeve transition = approximately 4.0" from Point A = Node 294.

End of thermal sleeve transition = approximately 9.5" from Point A = Node 387.

End of inner nozzle corner (nozzle side) = Node 553.

End of inner nozzle corner (vessel wall side) = Node 779.

Figure 1: Nozzle and Vessel Wall Thermal and Heat Transfer Boundaries 3.6 Finite Element Model The ANSYS program [6] will be used to perform the finite element analysis. A previously-developed axisymmetric model will be used [4, file FW.INP], except that temperature-dependent material properties will be used. Table 5 shows the applicable material properties [14].

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Table 5: Temperature-Dependent Material Properties Mean Young's Coefficient of Conductivity, Diffusivity, Specific Heat, Material Tempera-

Modulus, Thermal k

Cp No.

ture, IF E x 106 Expansion, (BTU/hr-ft-°F) d (BTU/Ibm-°F)

(psi) a x 10-(see Note 1)

(r, (see Note 5)

(in/in-°F)

SA533 Grade B, 70 27.8 6.4 23.5 0.458 0.105 A508 Class II 200 27.1 6.7 23.6 0.425 0.114 (see Note 2) 300 26.7 6.9 23.4 0.401 0.119 400 26.1 7.1 23.1 0.378 0.125 500 25.7 7.3 22.7 0.356 0.130 600 25.2 7.4 22.2 0.336 0.135 2

SS Clad 70 28.3 8.5 8.6 0.151 0.116 (see Note 3) 200 27.6 8.9 9.3 0.156 0.122 300 27.0 9.2 9.8 0.160 0.125 400 26.5 9.5 10.4 0.165 0.129 500 25.8 9.7 10.9 0.170 0.131 600 25.3 9.8 11.3 0.174 0.133 3

A508 Class I 70 29.3 6.4 35.1 0.695 0.103 (see Note 4) 200 28.6 6.7 33.6 0.613 0.112 300 28.1 6.9 32.3 0.561 0.118 400 27.5 7.1 30.9 0.512 0.123 500 27.1 7.3, 29.5 0.472 0.128 600 26.5 7.4 28.0 0.433 0.132 4

A106 Grade B 70 29.3 6.4 35.1 0.695 0.103 (see Note 4) 200 28.6 6.7 33.6 0.613 0.112 300 28.1 6.9 32.3 0.561 0.118 400 27.5 7.1 30.9 0.512 0.123 500 27.1 7.3 29.5 0.472 0.128 600 26.5 7.4 28.0 0.433 0.132 Notes:

I.

Convert to BTU/sec-in-0 F for input to ANSYS.

2.

3.

4.

5.

Properties of A508 Class II are used (3/4Ni-1/2Mo-1/3Cr-V).

Properties of 18Cr - 8Ni austenitic stainless steel are used.

Composition = C-Si; k and d for plain carbon steel are used [11].

Calculated as [k/(pd)]/1 23.

Stresses will be extracted and linearized at two locations, both on the inside surface. The critical safe end location is Node 192, which has the higheststress intensity due to thermal loading under high flow conditions [3, Section 4.0 and Figures 6 and 7]. The corresponding linearization path is from Node 192 to Node 187 (Figure 2 [3, Figure 7]).

The critical nozzle comer location is Node 657 at the base metal of the nozzle, chosen based upon the highest pressure stress [3, Section 4.0 and Figures 8 and 9]. The corresponding linearization path is from Node 657 to Node 645 (Figure 3 [3, Figure 9]).

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ELEAENT, S MNAT; 'NUM; ANS X:j~A1 MAP, 19 2 00 7 13i251:09 Node 187

(

Fee'dwater Nozzle,Finitp&: Ef~ementý M~del Figure 2: Safe End Linearization Path AN" AAR 19 27007 Feedwater Nozzle Finite Element: Model Figure 3: Nozzle Corner Linearization Path File No.: VY-19Q-301 Revision: 0.

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3.7 Nozzle Corner Effects The axisymmetric model has the effect of modeling the cylindrical RPV as spherical. To partially counter the resulting reduction in stress in the RPV wall, the radius in the model was increased by a factor of 1.5 [3, p. 8]. This yields a general membrane stress that equals the average of the hoop and axial stress for the cylinder.

Stresses from the axisymmetric analysis will need to be increased to account for the three-dimensional (3-D) geometry. A factor of 1.333 has been established in a previous calculation package that modeled the nozzle [3, p. 9], to achieve an overall pressure multiplication of 2.0. This is consistent with the maximum value used in prior VYNPS analyses [7, Appendix A, p. 4-10].

No other SCF is required at the nozzle comer inside surface, since this location has no stress riser.

3.8 Piping Interface Loads The previous analysis of the FW nozzle calculated membrane axial and shear stresses due to the piping interface loads by closed form solution, then combined them into stress intensities for the two locations of interest [2, Section 3.4]. All shear stresses were treated as existing in the same plane.

In this analysis, the stress components are recalculated in Section 4.3 taking into account through-wall distribution. Forces and moments are taken from the same reference as before [8, Table 3].

3.9 SCFs, Safe End In the previous analysis, an SCF of 1.34 was used for the safe end location for all load conditions

[2]. That value was obtained from the original design basis evaluation for the FW nozzle. For the current analysis, the SCF is updated to reflect modern-day ASME Code fatigue usage analysis methodology for consistency with the rest of the evaluation.

At the safe end inside surface, guidance is taken from the piping analysis rules in Subarticle NB-3600 of Section III of the ASME Code [1]. These rules specify stress indices C1, C2, and C3, which are applied to nominal stress to yield primary plus secondary membrane plus bending stress (P+Q);

and K1, K2, and K 3, which are applied to nominal stress along with the C factors to yield total stress (P+Q+F). The subscripts indicate the type of loading: 1 for pressure, 2 for moments, and 3 for thermal transients. Stress indices for a reducer are used.

Section 4.3 contains calculations of the safe end SCFs. For stresses due to piping loads, the moment stress indices C2 and K2 are applied to the nominal stress components at the safe end. For pressure stresses, the ANSYS model is sufficient to account for the effects of gross structural discontinuity such that C1 is not needed. To account for the effects of local structural discontinuity, K, is applied to the linearized P+Q stress to yield P+Q+F. These factors are conservatively applied to all, six components of the stress tensor.

For thermal stresses, C3 and K 3 are given as 1.0 [1, Table NB-3681(a)-l]; therefore, no SCF is required.

File No.: VY-19Q-301 Page 12 of 18 Revision: 0 F0306-O1 RO

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3.10 Environmental Fatigue Multipliers The environmental fatigue multipliers for the safe end and nozzle corner will be calculated in accordance with NUREG/CR-6583 methodology [15].

4.0 CALCULATIONS 4.1 Heat Transfer Coefficients, Condensation Condensation heat transfer coefficients are calculated with the formula shown in Section 3.4 for times during which the nozzle is filled with steam at Region.A temperature [10, Attachment 1, p. 3].

This is done in the sheet labeled "Condensation" in Excel workbook VY-19Q-301.xls in the project computer files. The highest heat transfer coefficient values for the transient temperature range are used. These are provided in Table 6.

Table 6: Condensation Heat Transfer Coefficients, Btu/hr-ft2-OF 0% flow, Region steam 1

598 2

3 1515 4

5 874 6

7 8

  • Linearly transition between the values for the adjacent regions.
    • Use values from Table 4, since these are bounding and there is no change in temperature.

4.2 Piping Interface Loads From general structural mechanics, the membrane plus bending stresses at the inside surface of a thick-walled cylinder are:

cz1 = axial stress due to axial force = Fz/A aTz2 = axial stress due to bending moment = Mxy(ID/2)/I Cyz = CYzl + az2 rro = shear stress due to torsion = Mz(ID/2)/J

,r, = shear stress due to shear force = 2Fxy/A, where F,, Fy, Fz, M., My, and M, are forces and moments at the pipe-to-safe end weld MxL = moment about x axis translated by length z = -L = Mx - Fy L MyL = moment about y axis translated by length z = -L = My + Fx L Mxy = resultant bending moment = (MxL2 + MyL2)0 5 Fxy = resultant shear force = (Fx2 + Fy2)0.5 ID, OD = inside and outside diameters A = area of cross section = (n/4)(OD 2 - ID 2)

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I = moment of inertia = (7r/64)(OD 4 - ID 4)

J = polar moment of inertia = (Tc/32)(OD 4 - ID 4)

Figure 4 shows the coordinate system for the forces and moments [8, Figure 1]. The shear stresses are expressed in a local coordinate system with r radial (X in ANSYS coordinates), 0 circumferential (Z in ANSYS coordinates), and Z axial (Y in ANSYS coordinates). Table 7 shows the calculation of stresses; ID, OD, and L are taken from the previous piping load stress calculations [2, Section 3.4].

Forces and moments are taken from the same reference as before, except that signs are chosen to maximize stress [8, Table 3].

Y t

t

?f lrz*

y"*. z' 7M1 rZ Figure 4: Coordinate System for Forces and Moments Table 7: Membrane Plus Bending Stresses Due to Piping Loads Fx, kip Fy, kip Fz, kip M., kip-in MY, kip-in M,, kip-in L, in MxL, kip-in MyL, kip-in MxY kip-in Fx,, kip-in OD, in ID, in A, inr I, in 4

J, in 4

czh ksi Gz2, ksi oa, ksi TrO, ksi T,. ksi Safe End 3.00

-15.00 3.20 336.00 156.00 480.00 12.09 517.31 192.26 551.88 15.30 11 "86 10.409 25.28 393.28 786.55 0.127 7.304 7.430 3.176 1.210 Nozzle Corner 3.00

-15.00 3.20 336.00 156.00 480.00 27.57 749.58 238.72 786.67 15.30 22.67 10.750 312.73 12300.41 24600.82 0.010 0.344 0.354 0.105 0.098 File No.: VY-19Q-301 Revision:- 0 Page 14 of 18 F0306-O1RO

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4.3 SCFs, Safe End Figure 5 shows the geometry parameters used in calculating stress indices for reducers [1, Figure NB-3683.6-1], and Figure 6 shows the feedwater nozzle safe end geometry [9]. Comparing the two figures gives the following values:

L= 0", r, = 0.75", D1 = 12.000", ti = (12 - 10.515)/2 = 0.7425" L 2 =0", r2 = 0.75", D2 = 10.840", t2 = (10.840 - 9.669)/2 = 0.5855" 10=

100 (L1 and L2 are taken as zero because the location of interest is on the radius of curvature.)

Figure 5: Reducer Geometry Parameters File No.: VY-19Q-301 Revision: 0 Page 15 of 18 F0306-O1 RO

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-4 0

I Figure 6: FW Nozzle Safe End Geometry bie No.: VY-19Q-301 Revision: 0 Page 16 of 18 F0306-O1RO

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Equations for stress indices are taken from the ASME Code [1, NB-3683.6]. For K1 and K2, since the location of interest is not on a weld, the equation for flush welds is used:

K1 = K2 = 1.1 - 0.1 Lm/(Dm tm) 0 5, where Lm/(Dm tm)0.5 = the lesser of L 1/(D1 t1)°5 and L 2/(D 2 t 2)0"5 Since L1 =

0, one finds:

K, = K 2 = 1.1 -0.1 (0)= 1.1 Since r, and r2 are less than 0.1D 1, C2 is given as:

C2 = 1.0 + 0.0185 a (Dn/tn) 0 5, where D,/tn = the larger of D1/t1 and D2/t2 The bounding D/t value is D2/t2 = 10.840/0.5855 = 18.514, so that:

C2 = 1.0 + 0.0185 (10) (18.514)05 = 1.796 C2 K 2 = 1.796 (1. 1) = 1.976 5.0 RESULTS OF ANALYSIS This calculation package specifies the ASME Code edition, finite element model, thermal and pressure transients (Table 1), and heat transfer coefficients (Tables 4 and 6) to be used in a fatigue usage analysis of the FW nozzle at VYNPS. Thermal transient and pressure stress components will be calculated using ANSYS, and piping load stress components are calculated herein, using closed form solutions (Table 7).

Linearized stress components at Nodes 192 (safe end inside surface) and 657 (nozzle comer inside surface) will be used for the fatigue usage analysis. At the nozzle comer, P+Q and P+Q+F pressure stress components will be increased by a factor of 1.333. For the nozzle comer location, the stresses used in the evaluation shall be for the base metal only; that is, the cladding material should be unselected prior to stress extraction. At the safe end, linearized P+Q pressure stress components will be multiplied by 1.1 to yield P+Q+F pressure stress components, and nominal stress components due to piping loads are multiplied by 1.796 to yield P+Q stress components and 1.976 to yield P+Q+F stress components.

The fatigue usage analysis will consider all six stress components, and will be performed using the NB-3200 rules of Section III of the ASME Code [1]. Calculated fatigue usage factors will be multiplied by the overall Fen of 1.74 for the safe end [2, Section 5.0] and values to be developed in a subsequent calculation package, to be assigned file number VY-19Q-303, for the nozzle comer.

File No.: VY-19Q-301 Page 17 of 18 Revision: 0 F0306-O1RO

CStructural Integrity Associates, Inc.

6.0 REFERENCES

1. American Society of Mechanical Engineers, Boiler and Pressure Vessel Code,Section III, Subsection NB, 1998 Edition with Addenda through year 2000.
2. SI Calculation Package, Fatigue Analysis of Feedwater Nozzle, Revision 0, SI File No. VY-16Q-302.
3. SI Calculation Package, Feedwater Nozzle Stress History Development for Greens Functions, Revision 0, SI File No. VY-16Q-301.
4. SI Calculation Package, Feedwater Nozzle Finite Element Model and Heat Transfer Coefficients, Revision 0, SI File No. VY-10Q-301.
5. Holman, J.P., Heat Transfer, Fifth Edition, McGraw-Hill, 1981.
6. ANSYS, Release 8.1 (w/Service Pack 1), ANSYS, Inc., June 2004. (Listed for reference only; this program is not used in this calculation package.)
7. Entergy Document VYC-378, Revision 0, Vermont Yankee Reactor Cyclic Limits for Transient Events, SI File No. VY-05Q-211.
8. GE Drawing No. 919D294, Revision 11, Sheet 7, Reactor Vessel, Spec. Control, SI File No. VY-05Q-241.
9. Ebasco Drawing 5920-234R1, 08/03/67, Safe End Detailfor Nozzles MK. N4A THRUN4D, (CB&I Contract 9-6201, Drawing #M14, Revision 0, 05/02/67), SI File No. VY-05Q-215.
10. Entergy Document EC No. 1773, Revision 0 (Design Input Revision 1), Environmental Fatigue Analysis for Vermont Yankee Nuclear Power Station, SI File No. VY-16Q-209.
11. Letter MLH-08-001 from M.L. Herrera (SI) to N. Lobo (ASME), ASME Code, Section 11, Part D, 1998 Edition and Later, Subpart 2, Table TCD, January 10, 2008.
12. Cheremisinoff, N., Heat Transfer Pocket Handbook, Gulf Publishing Co., Houston, 1984.
13. Keenan, J.H., Keyes, F.G., Hill, P.G., Moore, J.G, Steam Tables, Thermodynamic Properties of Water Including Vapor, Liquid, and Solid Phases (English Units), John Wiley & Sons, 1969.
14. American Society of Mechanical Engineeis, Boiler and Pressure Vessel Code,Section II, Part D, 1998 Edition with Addenda through year 2000.
15. NUREG/CR-65 83 (ANL-97/18), Effects of L WR Coolant Environments on Fatigue Design Curves of Carbon and Low-Alloy Steels, March 1998.

File No.: VY-19Q-301 Page 18 of 18 Revision: 0 F0306-O1RO

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