ML093360326

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Calculation, 0800368.320, Rev. 1, Optimized Weld Overlay Sizing for the 28 I.D. Outlet/Discharge Reactor Coolant Pump Nozzle
ML093360326
Person / Time
Site: Davis Besse 
Issue date: 05/27/2009
From: Sowah S
FirstEnergy Nuclear Operating Co, Structural Integrity Associates
To:
Office of Nuclear Reactor Regulation
References
L-09-268, TAC ME0477, TAC ME0478 0800368.320, Rev. 1
Download: ML093360326 (42)
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{{#Wiki_filter:Structural Integrity Associates, Inc. File No.: 0800368.320 CALCULATION PACKAGE Project No.: 0800368 Quality Program: [0 Nuclear [] Commercial PROJECT NAME: Davis-Besse Phase 2 Alloy 600 CONTRACT NO.: 49151, Rev.I CLIENT: PLANT: Welding Services, Inc (WSI) Davis-Besse Nuclear Power Station, Unit I CALCULATION TITLE: Optimized Weld Overlay Sizing for the 29" I.D. Outlet/Discharge Reactor Coolant Pump Nozzle Document Affected Project Manager Preparer(s) & Revision Pages Revision Description Approval Checker(s) Signature & Date Signatures & Date 0 1 - 17 Initial Issue A-] - A-9 Tony Giannuzzi Sandra Sowah B-I -B-I 3 AMG 01/27/09 SS 01/27/09 Peihua Jing PJ 01/27/09 Haiyang Qian MQ Q1/27/09 1 - 17 Revised Component A-i - A-9 Dimensions and Loads Angah Miessi B-I - B-13 GAM ___I/27/09 SS //09 Checkers: ,,Waiyang Qian MQ 5 / '409 Nader ýadeghi NS,./2Lo9 Page 1 of 18 r0306-01 RO

V Structural Integrity Associates, Inc. Table of Contents 1.0 IN TR O D U C TIO N.................................................................................................... 3

2.0 DESCRIPTION

OF CONFIGURATION AND REPAIR PROCESS...................... 3 3.0 ASME CODE CRITERIA........................................................................................ 3 4.0 WELD OVERLAY THICKNESS SIZING............................................................. 4 4.1 L oads..................................................................................................... ..... 4 4.2 M aterial properties........................................................................................ 8 4.3 G eom etry.................................................................................................... .. 8 4.4 Z -factor C alculation...................................................................................... 9 4.5 O W O L Sizing............................................................................................. 11 5.0 WELD OVERLAY LENGTH REQUIREMENTS............................................... 13 5.1 Structural Reinforcement............................................................................. 13 5.2 Preservice Exam ination............................................................................... 15 5.3 A rea L im itation........................................................................................... 16

6.0 CONCLUSION

S AND DISCUSSIONS............................................................... 16 7.0 RE FER E N C E S...................................................................................................... 17 List of Tables Table 1: Bounding Loads at Given Weld Location............................................................. 5 Table 2: Loads at W eld Locations (1)........................................................................................ 6 Table 3: Material Properties for RCP Nozzle/Piping at 556°F............................................. 8 Table 4: Dimensions for Overlay Sizing............................................................................ 8 Table 5: Z-factors for RCP Nozzle/Piping........................................................................ 10 Table 6: Properties at each OWOL Sizing Locations.............................................................. 11 Table 7: Optimized Weld Overlay Sizing Thickness Requirements................................. 13 Table 8: Minimum Required Overlay Length................................................................... 15 Table 9: OWOL Minimum Required Overlay Dimensions............................................... 16 List of Figures Figure 1: Transformation to the Local Coordinate System................................................. 7 Figure 2: Initial Locations of OWOL Sizing (Schematic Diagram).................................. 11 Figure 3: Final Locations of OWOL Sizing (Schematic Diagram).................................... 12 Figure 4: OWOL Geometry, Minimum Dimensions (Schematic Diagram)...................... 16 File No.: 0800368.320 Page 2 of 18 Revision: 1 F0306-01'

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1.0 INTRODUCTION

A weld overlay repair is being designed for the 28" I.D. Outlet/Discharge Reactor Coolant Pump (RCP) safe end-to-elbow welds at the Davis-Besse Nuclear Power Station, Unit 1. The purpose of this calculation package is to determine the required structural sizing for an optimized weld overlay (OWOL) repair of these welds, based on plant specific geometry and loadings and the design requirements of the Relief Request [9].

2.0 DESCRIPTION

OF CONFIGURATION AND REPAIR PROCESS The pump discharge nozzles are fabricated from A-351, Grade CF8M cast stainless steel [10, (pg. 1 of 4)], the safe end is A-376, Type 316 stainless steel [10, (pg. 1 of 4)], and the attached elbow is A-516, Grade 70 carbon steel [10, (pg. 1 of 4)]. The material of the dissimilar metal weld (DMW) between the safe-end and elbow is Alloy 82/182 [10, (pg. 1 of 4)], and the stainless steel weld between the nozzle and safe-end is assumed to be Type 308 stainless steel deposited with the submerged arc welding (SAW) process as a conservative lower bound. The optimized overlay repair will be performed using primary water stress corrosion cracking (PWSCC) resistant Alloy 52M material deposited around the circumference of the configuration. The overlay material will be deposited using the gas tungsten arc welding (GTAW) process. 3.0 ASME CODE CRITERIA The basis for sizing an optimized weld overlay (OWOL) is to utilize the outer 25 percent of the existing weld thickness and to provide sufficient material over the existing weld and base metal such that the ASME Section XI Appendix C flaw acceptance criteria are met if there is a flaw beneath the weld overlay and outer 25 percent of the existing weld. The basis for design of the OWOL is provided in MRP-169 [1, 2]. The ASME Code Section XI Code of Record for Davis-Besse is the 1995 Edition with Addenda through 1996 [3]. Safety factors are provided in Appendix C of this Code for evaluation of flaws in austenitic stainless steel piping. These safety factors (2.77 for Normal/Upset (N/U) loadings (Service Level A/B) and 1.39 for Faulted (F) (Service Level D) are used for the weld overlay sizing. The flow stress is taken as 3Sn for the affected materials as defined in Section XI, Appendix C [3]. In the evaluation of flaws using net section collapse criteria, a Z-factor is employed to correct the solution for low toughness materials. These factors are provided in ASME Section XI, Appendix C, Section C-3320 for stainless steel and in Appendix H, Section H-6300 for ferritic materials. A proposed Z-factor for Alloy 600 materials is provided in Reference 4. File No.: 0800368.320 Page 3 of 18 Revision: 1 F0306-01

UStructural Integrity Associates, Inc. 4.0 WELD OVERLAY THICKNESS SIZING Appendix B provides a method and spreadsheets for evaluating the thickness for optimized weld overlays where separate material properties and geometry may be considered for the base material and the overlay. This method is utilized in this calculation for the OWOL where credit is taken for the outer 25% of the existing weld thickness (excluding consideration of the underlying cladding). Although only the weld between the safe-end and elbow is constructed of PWSCC-susceptible Alloy 82/182 material, the overlay may extend over the stainless steel weld between the safe-end and the nozzle to accommodate future inspections. Thus for conservatism, it is also assumed that a flaw with depth of 75 percent of the base material and 3600 in circumference will exist in the stainless nozzle-to-safe end weld. For the safe end-to-elbow weld, the presence of the cladding on the elbow side of the weld is neglected, consistent with ASME Section III [5] design rules. 4.1 Loads The design of the OWOL is based on the normal operating pressure of 2255 psig and a normal operating temperature of 556°F [ 10, (pg. 1 of 4)]. The following service level load combinations are used to determine the weld overlay design: Primary Loads: Service Level A/B (Normal/Upset): Service Level C (Emergency): Service Level D (Faulted) : Deadweight (DW) + Operating Basis Earthquake (OBE) DW + SSE DW + SRSS (SSE+LOCA) Given the low toughness materials, thermal forces and moments must be considered. The resulting loads are then used as inputs for the OWOL spreadsheet calculations shown in Appendix A. Thus: Total Loads: Service Level A/B (Normal/Upset): Service Level C (Emergency): Service Level D (Faulted) : Deadweight (DW) + OBE + TH DW + SSE +TH DW + SRSS (SSE+LOCA)+TH File No.: 0800368.320 Revision: 1 Page 4 of 18 F0306-01

Structural Integrity Associates, Inc. I -~I UI UI UI U U U i m m m - m m m m m m m m - m m m m m m m File No.: 0800368.320 Revision: 1 Page 5 of 18 F0306-01:

V Structural Integrity Associates, Inc. m m m m m m m - m m m m m m___ m m m m m m m m m mm~ m m m File No.: 0800368.320 Revision: 1 Page 6 of 18 F0306-01I

V Structural Integrity Associates, Inc. File No.: 0800368.320 Revision: 1 Page 7 of 18 F0306-011

V Structural Integrity Associates, Inc. 4.2 Material properties Table 3 shows the material properties for the materials considered in this analysis, including the allowable stress intensity, yield strength, ultimate tensile strength from ASME Code, Section II, Part D [7]. The properties are interpolated between 500°F and 600'F for the operating temperature of 556°F [10, (pg. 1 of 4)]. Table 3: Material Properties for RCP Nozzle/Piping at 556°F Component/Material ASME Code, Section II, Part D y (ksi) S. (ksi) S, (ksi) afIOW (ksi) Component/___ater___ Material Designation (k S sS s ok RCP Nozzle Cast Stainless Steel 19.3 17.4 67.2 52.2 A-351, Grade CF8M DM Weld Alloy 600 SB-166 (N06600) 30.1 23.3 80.0 69.9 (82/182) Overlay Alloy 690 SB 166 (N06690) 27.7 23.3 80.5 69.9 (Alloy 52M) Bar/Rod RCP Safe-End AC, Type-316 Stainless Steel 19.4 17.4 71.8 52.3 A-376, Type 316 RCP Piping Carbon Steel 29.9 19.9 70.0 59.8 A-516, Grade 70 1 Stainless Steel Weld (1) Stainless Steel Type 316 19.4 17.4 71.8 52.3 (Assumed) Note: 1. Material properties of stainless steel weld are conservatively assumed to be the same as those of the nozzle. 4.3 Geometry m_________ File No.: 0800368.320 Revision: 1 Page 8 of 18 F0306-01

V Structural Integrity Associates, Inc. 4.4 Z-factor Calculation Multiple locations along the RCP nozzle assembly are considered for the weld overlay sizing. For this calculation, the properties for the existing base material under the overlay are based on either the material at the side of the weld or the weld material itself at each of the locations considered, using associated material properties and Z-factors. The Z-factor is calculated for each material at the nozzle, the overlay, the DMW, the safe end, and the elbow. At the nozzle: The nozzle is identified as cast stainless steel. Per 1995 ASME Code Section XI Appendix C [3], Section C-3320, the Z-factors are calculated for austenitic weld materials fabricated using shielded metal arc (SMAW) or submerged arc (SAW) welding: Z = 1.15[1+0.013(D-4)] for SMAW (1) Z = 1.30[1+0.010(D-4)] for SAW (2) Where: D = outside diameter of component, in. For conservatism, the Z-factors for the SAW (Equation 2) are applied for stainless steel weld and the cast austenitic stainless steel. For the overlay: The overlay is identified as a GTAW weld, thus for Alloy 52M, the Z-factor is I per ASME Code Section XI Appendix C [3] and Reference 14. For the DMW: The DMW weld material is Alloy 82/182. Thus, the Z-factor is taken from Reference 4. Per Reference 4, the Z-factors are calculated as follows: Z = 0.00065D3 - 0.01386D2 + 0.1034D + 0.902 for D < 8" Z = 0.0000022D 3 - 0.0002D 2 + 0.0064D + 1.1355 for D > 8" where: D = outside diameter of component, in. A Z-factor of 1.21 is calculated for the DMW weld using D=34. 1" from Table 4. For the safe end: Per Reference 14 and ASME Code Section XI Appendix C [3], the safe end Z-Factor is 1, since it is identified as austenitic stainless steel base material. File No.: 0800368.320 Page 9 of 18 Revision: 1 F0306-01

V Structural Integrity Associates, Inc. For the elbow: The elbow is identified as carbon steel. The Z-factors for ferritic/carbon steel base metals and associated weld metals are calculated from the 1995 ASME Section XI Appendix H, Section H-63 10. Depending on the case, the Z-factor is calculated using Equations 3 or 4 shown below. Case 1: For Seamless/Welded Wrought Carbon Steel pipe and pipe fitting with Sy < 40 ksi and for welds made using carbon steel electrodes. Z = 1.20[1+0.021A(NPS-4)] (3) Case 2: For carbon and alloy steel (including SAW and SMAW welds) with Sy > 40 ksi and Tensile Strength < 80 ksi. Z = 1.35[1+0.0184A(NPS-4)] (4) The area (A) is calculated per value of R. A = [0.125(R/t) - 0.25]o.25 for 5 < R/t < 10 A = [0.4(R/t) - 3.0]0.25 for 10 < R/t < 20 Where: NPS R t = nominal pipe size, in. = mean radius, in. = thickness, in. Since the elbow base material is considered in this evaluation and, per Table 3, Sy < 40 ksi, the Z-factor for Case 1 (Equation 3) is applied for the carbon steel elbow. The Z-factors calculated for each component are summarized in Table 5. Table 5: Z-factors for RCP Nozzle/Piping Component/Material ASME Code, Section II, Part D Z-factor Material Designation Z-factor RCP Nozzle Cast Stainless Steel 1.69 A-351, Grade CF8M DM Weld Alloy 600 SB-166 (N06600) 1.21 (82/182) Bar Overlay Alloy 690 SB 166 (N06690) 1.00 (Alloy 52M) Bar/Rod RCP Safe-End ACP Type-316 Stainless Steel 1.00 A-376, Type 316 RCP Piping Carbon Steel 1.83 A-516, Grade 70 Stainless Steel Weld, Stainless Steel Type 316 1.69 Nozzle Side (Assumed) Stainless Steel Weld, Stainless Steel Type 316 1.68 Safe End Side (Assumed) File No.: 0800368.320 Revision: 1 Page 10 of 18 F0306-01

UStructural Integrity Associates, Inc. 4.5 OWOL Sizing As shown in Figure 2, a total of eight locations are setup for initial consideration of the sizing calculation. The geometry and material properties associated with each location are given in Table 6. Figure 2: Initial Locations of OWOL Sizing (Schematic Diagram) Table 6: Properties at each OWOL Sizing Locations 1 2 3 4 Location Nozzle Nozzle/SSW SE Weld/SSW SE/SSW Do, in 34.2 34.2 33.5 33.5 Di, in 28.166 28.166 28.166 28.166 Z 1.69 1.69 1.68 1.00 Uflow (ksi) 52.2 52.2 52.3 52.3 5 6 7 8 Location SE/DMW SE Weld/DMW Elbow/DMW Elbow Do, in 33.5 33.5 34.1 34.1 Di, in 28.000 28.000 28.000 28.625 Z 1.00 1.21 1.21 1.83 3flow (ksi) 52.3 69.9 69.9 59.8 Among these eight locations, Location (1) and Location (2) are reduced to one case, since SSW weld material (Type 316 stainless steel) properties are assumed to be the same as those of the nozzle. Location (3) is chosen between Locations (3) and (4), since the Z-factor at location (3) is higher, thus yields more conservative results. For the same reason, Location (6) is chosen over Location (5). Location (8) is considered due to possible susceptibility to fatigue crack propagation initiated from the weld butter at the interface with the cladding due to PWSCC. For Locations (7) and (8), Location (8) governs because it has a higher Z-factor and a lower flow stress. In summary, four locations are chosen to be evaluated, as shown in Figure 3. File No.: 0800368.320 Revision: 1 Page 11I of 18 F0306-01:

V Structural Integrity Associates, Inc. (1) (2)/ NOZZLE (3) (4) I I I I Il* OVERLAY SSW WELD II' SAFE END \\DMW WELD I I I I ELBOW I I I Figure 3: Final Locations of OWOL Sizing (Schematic Diagram) Weld overlay thickness sizing is performed based on the methods presented in Appendix B. The spreadsheets discussed in Appendix B were developed to allow for rapid solution of weld overlay thickness using net section collapse methodology [8]. The weld overlay sizing (thickness) is based on both evaluation of N/U (Service Level B), and Faulted (Service Level D) conditions. Thermal is included in both N/U and F conditions for overlay sizing for thermal expansion bending stresses. The loads in Emergency (Service Level C) case is bounded by Faulted case, as shown in Table 2, and is therefore not included. It is further assumed for conservatism that the flaw contained in the base material is 75% through the underlying material thickness and fully circumferential. In determining the limit load moment, it is assumed that the base material in compression is at the flow stress of 3 Sm, as per the requirements of Section XI, Appendix C [3]. In the determination of stresses due to elbow loadings, there is no explicit guidance in MRP-169 [1, 2] and the ASME Code, Section XI [3] for incorporation of axial forces due to piping loads in determining stress values. In this calculation for selected locations, the overlay thickness was determined excluding axial forces (as is standard for a full structural overlay) and reported. The detailed results for the OWOL sizing are shown in the spreadsheet files listed in Appendix A. The resulting thickness requirements are shown in Table 7 for N/U and F loadings with axial forces excluded. File No.: 0800368.320 Revision: 1 Page 12 of 18 F0306-0 1

V Structural Integrity Associates, Inc. Table 7: Optimized Weld Overlay Sizing Thickness Requirements Flaw Location Thickness N/U Loading (in) Thickness F Loading (in) Location 1, SSW, Nozzle Side 0.5287 0.5492 Location 2, SSW, Safe End Side 0.5645 0.5939 Location 3, DMW, Safe End Side 0.3251 0.3800 Location 4, DMW, Elbow Side 0.6052 0.6543 Notes: DMW = Dissimilar Metal Weld, SSW = Stainless Steel Weld For conservatism, the thicker section on either side of each weld is taken. For the DMW weld, the minimum required overlay thickness is 0.6543 inch. For the SSW weld, the required thickness is 0.5939 inch. 5.0 WELD OVERLAY LENGTH REQUIREMENTS The determination of the weld overlay length must consider three requirements: (1) length required for structural reinforcement, (2) length required for preservice examination access of the overlaid weld and (3) limitation on the area of the elbow surface that can be overlaid using ambient temperature temperbead welding. 5.1 Structural Reinforcement The structural reinforcement requirements are expected to be satisfied if the weld overlay length is 0.75 Rt on either side of the susceptible weld being overlaid [6], where R is the outside radius and t is the thickness of the original pipe. In this evaluation, the overlay length is determined from shear stress calculations to assure ASME Code, Section III [5] compliance. In this evaluation, it is conservatively assumed that all axial forces are transferred from the safe end completely into the overlay and then into the elbow. No credit is taken for load transfer through the unflawed outer 25% of the base metal. The section along the length of the overlay is evaluated for axial-radial shear due to transfer of axial load from the overlaid item to the overlay. Subparagraph NB-3227.2 [5] limits the average primary pure shear due to any loadings except Service Level D (Faulted) to 0.6Sm. This is equivalent to half the limit of 1.2Sm on general primary membrane stress intensity due to Service Level C (Emergency) loadings. Thus, the shear limit of 0.5Sm, equivalent to half of 1.0 Sm for stress intensity, is conservatively used for the N/U load combination. For Level D (faulted) conditions, the stress intensity limit is the lesser of 2.4Sm or 0.7Su [3], equivalent to the lesser of 1.2Sm and 0.35Su for shear stress, using half of the tension allowable values. File No.: 0800368.320 Page 13 of 18 Revision: 1 F0306-011

Structural Integrity Associates, Inc. Shear stress at the overlay-base material interface due to axial force through overlay equals: Axial force applied to overlay cross-section + Area of overlay-base material interface beyond fusion line Moment load due to attached piping Section modulus of area of overlay-base material interface beyond fusion line Internal pressure x (at x Ro2component) + Length of overlay-base material interface x circumference @ overlay ID Applied moment Section modulus of overlay-base material interface band = P x n x Ro2/A, + M/Ss where: Ro = outside radius of overlaid item at weld, in. L = length of overlay at outside surface of overlaid item on one side of crack, in. A, = shear area, 2mrRo L, in2 Ss = section modulus, 7rRo2L, in' P = pressure, psig M = resultant moment from piping interface loads at weld, lb-in

Thus, r = PTtRo2/(2ntRoL) + M/(ncR 0 2L)

Solving for L and equating c with the allowable shear stress (Sallow) yields: L = [PRo/2 + M/(TCRo02 )]/Sallow, where: Sallow = 0.5Smn (Normal/Upset) = 0.6Sm (Emergency) = The lesser of 1.2Sm and 0.35Su (Faulted) This equation for the required weld overlay length is implemented in Table 8 for all components. The greater value of the required overlay length will be taken. The material properties are evaluated at the normal operating temperature of 556°F [10, (pg. 1 of 4)] using Section II, Part D of the ASME Code [7]. Thermal loads are not included in determining the weld overlay length since average primary pure shear is being calculated. File No.: 0800368.320 Page 14 of 18 Revision: 1 F0306-011

Structural Integrity Associates, Inc. Table 8: Minimum Required Overlay Length Shear length Calculation SE Side DMW Elbow Side DMW Ro, in 16.75 17.03 Material A-376 Type 316 A-516 Grade 70 Sm, ksi 17.4 19.9 Normal/Upset 0.5Sm, ksi 8.7 10.0 Emergency 0.6Sm, ksi 10.5 12.0 Faulted 1.2Sm, ksi 20.9 23.9 Su, ksi 71.8 70.0 Faulted 0.35Su, ksi 25.1 24.5 Normal/Upset L, in 3.6726 3.2028 Emergency L, in 3.9932 3.4587 Faulted L, in 3.1518 2.7074 The required overlay thickness is calculated at each side of the DMW. The design drawing implements a configuration that meets all thickness and length requirements, based on the bounding minimum values. The lengths shown above ensure adequate shear stress transfer along the length of the weld overlay. Service Level C (Emergency) is the most limiting. This length is sufficient to transfer the imposed loads and maintain stresses (shear) within the appropriate ASME Code allowables. 5.2 Preservice Examination Weld overlay access for preservice examination requires that the overlay length and profile be such that the overlaid weld and any adjacent welds that are to be inspected can be examined using the required NDE techniques. This requirement could cause the overlay length to be longer than required for structural reinforcement. The specific overlay length required for preservice examination is determined by qualified NDE personnel based on the examination techniques and proximity of adjacent welds to be inspected. File No.: 0800368.320 Revision: 1 Page 15 of 18 F0306-011

V Structural Integrity Associates, Inc. 5.3 Area Limitation Per Table NB-4622.7(b)-1 [5], the elbow is limited by the temperbead requirements and an area of limitation calculation is required for the elbow. Thus, the total weld overlay surface area is limited to 600 in2 on the elbow body ferritic base material per the Relief Request [9] when using ambient temperature temperbead welding to apply the overlay. Using a diameter of 34.1 ", the maximum length is limited to 600/ (nDo) = 5.6" on the elbow. The minimum required overlay length on the elbow (3.4587"), determined above and shown in Table 8, is less than this limit.

6.0 CONCLUSION

S AND DISCUSSIONS This calculation package documents the development of an optimized weld overlay design for the RCP discharge safe end-to-elbow weld at Davis-Besse Nuclear Power Station, Unit 1. Table 9 and Figure 4 summarize the minimum required overlay dimensions for an optimized overlay. This design has been based on the Relief Request [9] requirements for an optimized weld overlay. 0.3800" ~-3.9932" - 0.6543" 3.4587" 0 V E R L A Y SAFE END ELBOW Figure 4: OWOL Geometry, Minimum Dimensions (Schematic Diagram) Table 9: OWOL Minimum Required Overlay Dimensions [ Location DMW, Elbow Side DMW, SE Side SSW, SE Side SSW, Nozzle Side Thickness, (in) 0.6543 0.3800 0.5939 0.5492 t Length (in) 3.4587 3.9932 NA NA I I File No.: 0800368.320 Revision: 1 Page 16 of 18 F0306-01i

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7.0 REFERENCES

1. Materials Reliability Program: Technical Basis for Preemptive Weld Overlays for Alloy 82/182 Butt Welds in PWRS (MRP-169), EPRI, Palo Alto, CA and Structural Integrity Associates, Inc, San Jose CA: 2005, 1012843.
2. Materials Reliability Program: Technical Basis for Preemptive Weld Overlays for Alloy 82/182 Butt Welds in PWRS (MRP-169), Revision 1, EPRI, Palo Alto, CA:

2008, Final Report, June 2008, 1016602.

3. ASME Boiler and Pressure Vessel Code, Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components, 1995 Edition with Addenda through 1996.
4. Wilkowski, G, et.al., "Determination of the Elastic-Plastic Fracture Mechanics Z-factor for Alloy 182 Weld Metal Flaws for Use in the ASME Section XI Appendix C Flaw Evaluation Procedures," PVP2007-26733, ASME PVP Conference 2007.
5. ASME Boiler and Pressure Vessel Code, Section III, Rules for Construction of Nuclear Facility Components, 2001 Edition with Addenda through 2003.
6. ASME Boiler and Pressure Vessel Code, Code Case N-740-2, "Full Structural Dissimilar Metal Weld Overlay for Repair or Mitigation of Class 1, 2, and 3 Items, Section XI, Division 1."
7. ASME Boiler and Pressure Vessel Code, Section II, Part D, Material Properties, 2001 Edition with Addenda through 2003.
8.

Deardorff,

A, et.al., "Net Section Plastic Collapse Analysis of Two-Layered Materials and Application to Weld Overlay Design," PVP2006-ICPVT 11-93454, ASME PVP Conference 2006.

9. SI Report 0800368.401, "Proposed Relief Request In Accordance with 10 CFR 50.55a(a)(3)(i) - Alternative Provides Acceptable Level of Quality and Safety," (for revision number, refer to SI Project Revision Log, latest revision).
10. FirstEnergy Nuclear Operating Company Design Input, Rev. 1, "Inputs List - Design Data," Received 9/12/08, SI File No. 0800368.241.

File No.: 0800368.320 Page 17 of 18 Revision: 1 F0306-01

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14. Westinghouse Electric Corporation, "Toughness of Austenitic Stainless Steel Pipe Welds," EPRI Report NP-4 768, Research Project 123 8-2, Topical Report, Electric Power Research Institute, October 1986.

File No.: 0800368.320 Revision: 1 Page 18 of 18 F0306-01

Structural Integrity Associates, Inc. Appendix A WELD OVERLAY SIZING SPREADSHEET FILES FOR OWOL LOCATIONS AND LOADING CONDITIONS A.1 LOCATION 4: ELBOW WITH DMW ALLOY 82/182 INTERFACE FOR NORMAL/UPSET LOADING CONDITIONS.............................................. A-2 A.2 LOCATION 4: ELBOW WITH DMW ALLOY 82/182 INTERFACE FOR FAULTED LOADING CONDITIONS........................................................... A-3 A.3 LOCATION 3: DMW AT SAFE END SIDE FOR NORMAL/UPSET LOADING CONDITIONS....................................................... A-4 A.4 LOCATION 3: DMW AT SAFE END SIDE FOR FAULTED LO AD IN G CON D ITION S....................................................................................... A -5 A.5 LOCATION 2: SSW AT SAFE END SIDE FOR NORMAL/UPSET LOADING CONDITIONS....................................................... A-6 A.6 LOCATION 2: SSW AT SAFE END SIDE FOR FAULTED LOADING CONDITIONS................................................................... A-7 A.7 LOCATION 1: NOZZLE AT sSW INTERFACE FOR NORMAL/UPSET LOADING CONDITIONS....................................................... A-8 A.8 LOCATION 1: NOZZLE AT SSW INTERFACE FOR FAULTED LOADING CONDITIONS........................................................... A-9 A.9 OUTER DIAMETER CALCULATIONS FOR THE NOZZLE........................ A-10 A.10 OUTER DIAMETER CALCULATIONS FOR THE ELBOW......................... A-1 File No.: 0800368.320 Page A-i of A-1I Revision: 1 F0306-01

V Structural Integrity Associates, Inc. A.1 LOCATION 4: ELBOW WITH DMW ALLOY 82/182 INTERFACE FOR NORMAL/UPSET LOADING CONDITIONS Spreadsheet entitled "DavisBesseDischargeNozzle.xls" Weld Overlay Sizing Based on Load Input (Version 1 - 5June08)

Pressure, 2255 psi Crack Faxial 0 kips a,OL+Lig 0 degrees - half angle M, prim.

11581.21 in-kips P3,pipe 180 degrees - half angle M, therm 16275.4 in-kips a/t, pipe 0.75 a/t Fpress 2054.375 kips INPUT is Lt. Green Crack Pressure Fraction Notes: Phi Factors are reduction factors that may be applied to flow stress in each regic Pipe Ligt 0 Crack face pressure fractions are portion of c Pipe Metal Area = 267.5193 Pipe Crk 0 Stresses Using Piping Equations (Info) Pipe Z (shell) = 2096.094 WOL Crk 0 Axial Pressure = 7.067 ksi Shell Theory Z 2096.094 Axial Load = 0.000 ksi Shell Theory A 267.5193 Primary Bending 5.525 ksi Pipe Z (Thk. Cyl.) 2096.094 Thermal Bending = 7.765 ksi Pipe A (Thk. Cyl.) 267.5193 Pipe (Matl B) OD t Sfiow Phib,t Phib,c 2.717 in 59.8 ksi 1-1- WOL(Matl A) I overlay 0.605232 in Sflow 69.9 ksi Phia,t 1 - Phia,c 1 - Case 1 Case 2 Case 3 P3 < TT - y Crack Above Neutral Axis 13 = rr - y Crack To Neutral Axis or Crack Below Takes Compression 13 > Tr - y Crack Below Neutral Axis and Takes no Compression y = half angle up to neutral axis Note that any weld overlay angle a must be above neutral axis and have a half angle < pipe crack half angle Nominal Stresses (Thin Shell Solution) Axial Pr 7.067 ksi Axial Ld 0.000 ksi Total Axial Stress 7.067 ksi Pm Prim. Bend. Stress 5.525 ksi Pb Therm Bend. Stress 7.765 ksi Pe Weld Ovrlay Z Factor Base Metal Z Factor SFm SFb 1 1.83 2.77 2.77 <cntl~shlft A <cnII>shift C Size Case 1 Overlay Size Case 2 Overlay Size Case 3 Overlay For OL Z = 1, Pb,prim = [P'b + (SFb/SFm)Pm - Z M* Pe] / [SFb(I+M* (Z-1))] - Pm For OL Z > 1, Pb,prim = [P'b + (SFb/SFm)Pm]/[SFb{ZoI(1-M*)+Zbm(M*)}] - Pm - Pe/SFb Case 1 1< rr-y 2 1=rTT-y 3 1> IT-Y y, degrees y+p3 check 32.39 INVALID 41.61 VALID 75.27 VALID Limit Mom Limit Str. in-lb P'b, ksi 112721.7 53.777 101764.4 48.550 92930.7 44.335 M* Pb,prim 0.268 9.782427 Run Case I for These Results if F26 = VALID 0.480 5.525941 Results are for Case 2 0.480 4.438217 Run Case 3 for These Results if F28 = VALID Pb' WolZ=1 WolZ>1 9.782 8.103 5.526 4.485 4.438 3.397 Current Results are for Case 2 Weld Overlay Thickness =.6052 inch File No.: 0800368.320 Revision: 1 Page A-2 of A-11 F0306-01

V Structural Integrity Associates, Inc. A.2 LOCATION 4: ELBOW WITH DMW ALLOY 82/182 INTERFACE FOR FAULTED LOADING CONDITIONS Spreadsheet entitled "DavisBesseDischargeNozzle.xls"

Pressure, Faxial M, prim.

M, therm Weld Overlay Sizing Based on Load Input (Version 1 - 5June08) 2255 psi Crack 0 kips a,OL+Lig 0 degrees - half angle 41491.95 in-kips P3,pipe 180 degrees - half angle 16275.4 in-kips a/t, pipe 0.75 a/t INPUT is Lt. Green Crack Pressure Fraction Notes: Phi Factors are reduction factors that may be applied to flow stress in each regic Pipe Ligt 0 Crack face pressure fractions are portion of c Pipe Metal Area = 267.5193 Pipe Crk 0 Stresses Using Piping Equations (Info) Pipe Z (shell) = 2096.094 WOL Crk 0 Axial Pressure = 7.067 ksi Shell Theory Z 2096.094 Axial Load = 0.000 ksi Shell Theory A 267.5193 Primary Bending = 19.795 ksi Pipe Z (Thk. Cyl.) 2096.094 Thermal Bending = 7.765 ksi Pipe A (Thk. Cyl.) 267.5193 Fpress 2054.375 kips Pipe (Matl B) OD t Sflow Phib,t Phib,c 2.717 in 59.8 ksi 1-1- WOL(Matl A) t overlay 0.654345 in Sflow 69.9 ksi Phia,t 1 - Phia,c 1 - Case 1 Case 2 Case 3 P< r - y Crack Above Neutral Axis 3 = rr - y Crack To Neutral Axis or Crack Below Takes Compression 3 > rr - y Crack Below Neutral Axis and Takes no Compression y = half angle up to neutral axis Note that any weld overlay angle a must be above neutral axis and have a half angle < pipe crack half angle Nominal Stresses (Thin Shell Solution) Axial Pr 7.067 ksi Axial Ld 0.000 ksi Total Axial Stress 7.067 ksi Pm Prim. Bend. Stress 19.795 ksi Pb Therm Bend. Stress 7.765 ksi Pe Weld Ovday Z Factor Base Metal Z Factor SFm SFb 1 1.83 1.39 1.39 <cnbtlshift B <cntl~shift C Size Case 1 Overlay Size Case 2 Overlay Size Case 3 Overlay For OL Z = 1, Pb,prim = [P'b + (SFb/SFm)Pm - Z M* Pe] / [SFb(I+M* (Z-1))] - Pm For OL Z > 1, Pb,prim = [P'b + (SFb/SFm)Pm]/[SFb{ZoI(1-M*)+Zbm(M*))] - Pm - Pe/SFb Case 1 O3<Tr-y 2 P=rr-y 3 P3>rr-y y, degrees y+p check 33.44 INVALID 42.83 VALID 75.88 VALID Limit Mom Limit Str. in-lb P'b, ksi 118304.4 56.440 107090.1 51.090 97335.6 46.437 M. 0.241 0.461 0.461 Pb,prim 28.96149 Run Case 1 for These Results if F26 = VALID 19.79489 Results are for Case 2 17.37288 Run Case 3 for These Results if F28 = VALID Pb'- WolZ=1 WolZ>1 28.961 25.427 19.795 17.615 17.373 15.193 Current Results are for Case 2 Weld Overlay Thickness =.6543 inch File No.: 0800368.320 Revision: 1 Page A-3 of A-11 F0306-01I

I Structural Integrity Associates, Inc. A.3 LOCATION 3: DMW AT SAFE END SIDE FOR NORMAL/UPSET LOADING CONDITIONS Spreadsheet entitled "DavisBesseDischargeNozzle.xts"

Pressure, Faxial M, prim.

M, therm Weld Overlay Sizing Based on Load Input (Version 1 - 5JuneO8 2255 psi Crack 0 kips a,OL+Lig 0 degrees - half angle 11581.21 in-kips 13,pipe 180 degrees-half angle 16275.4 in-kips a/t, pipe 0.75 a/t INPUT is Lt. Green Crack Pressure Fraction Notes: Phi Factors are reduction factors that may be applied to flow stress in each regic Pipe Ligt 0 Crack face pressure fractions are portion of c Pipe Metal Area = 265.6609 Pipe Crk 0 Stresses Using Piping Equations (Info) Pipe Z (shell) = 2042.268 WOL Crk 0 Axial Pressure 6.868 ksi Shell Theory Z 2042.268 Axial Load = 0.000 ksi Shell Theory A 265.6609 Primary Bending = 5.671 ksi Pipe Z (Thk. Cyl.) 2042.268 Thermal Bending = 7.969 ksi Pipe A (Thk. Cyl.) 265.6609 Fpress 1987.587 kips Pipe (Mat] B) OD t Sflow Phib,t Phib,c WOL(Matl A) 33.5 in 2.75 in 69.9 ksi 1-1- t overlay Sflow Phia,t Phia,c Case 1 Case 2 Case 3 0.325097 in 69.9 ksi 1-1- p3 < Tr - y Crack Above Neutral Axis P3= n - y Crack To Neutral Axis or Crack Below Takes Compression 3 > "rr - y Crack Below Neutral Axis and Takes no Compression y = half angle up to neutral axis Note that any weld overlay angle a must be above neutral axis and have a half angle < pipe crack half angle Nominal Stresses (Thin Shell Solution) Axial Pr 6.868 ksi Axial Ld 0.000 ksi Total Axial Stress 6.868 ksi Pm Prim. Bend. Stress 5.671 ksi Pb Therm Bend. Stress 7.969 ksi Pe Weld Ovrlay Z Factor Base Metal Z Factor SFm SFb 1 1.21 2.77 2.77 .Ccitt~shift A <cntl~shif B <cnitl~shift C Size Case 1 Overlay Size Case 2 Overlay Size Case 3 Overlay For OL Z = 1, Pb,prim = [P'b + (SFb/SFm)Pm - Z M* Pe] / [SFb(I +M* (Z-1))] - Pm For OL Z > 1, Pb,prim = [P'b + (SFb/SFm)Pm]/[SFb{Zol(1-M*)+Zbm(M*))] - Pm - Pe/SFb Case 1 3< Tr-Y 2 = TT-y 3 I3>TT-y y, degrees y+0 check 25.65 INVALID 34.16 VALID 73.04 VALID Limit Mom Limit Str. in-lb P'b, ksi 89926.8 44.033 80158.0 39.250 74359.2 36.410 M. Pb,prim 0.527 8.024824 Run Case 1 for These Results if F26 = VALID 0.672 5.67075 Results are for Case 2 0.672 4.772507 Run Case 3 for These Results if F28 = VALID Pb' WolZ=1 WolZ>1 8.025 6.800 5.671 4.845 4.773 3.946 Current Results are for Case 2 Weld Overlay Thickness =.3251 inch File No.: 0800368.320 Revision: 1 Page A-4 of A-1 F0306-01

V Structural Integrity Associates, Inc. A.4 LOCATION 3: DMW AT SAFE END SIDE FOR FAULTED LOADING CONDITIONS Spreadsheet entitled "DavisBesseDischargeNozzle.xls"

Pressure, Faxial M, prim.

M, therm Weld Overlay Sizing Based on Load Input (Version 1 - 5June08) 2255 psi Crack 0 kips a,OL+Lig 0 degrees - half angle 41491.95 in-kips P,pipe 180 degrees - half angle 16275.4 in-kips a/t, pipe 0.75 aft INPUT is Lt. Green Crack Pressure Fraction Notes: Phi Factors are reduction factors that may be applied to flow stress in each regic Pipe Ligt 0 Crack face pressure fractions are portion of c Pipe Metal Area = 265.6609 Pipe Crk 0 Stresses Using Piping Equations (Info) Pipe Z (shell) = 2042.268 WOL Crk 0 Axial Pressure = 6.868 ksi Shell Theory Z 2042.268 Axial Load = 0.000 ksi Shell Theory A 265.6609 Primary Bending = 20.317 ksi Pipe Z (Thk. Cyl.) 2042.268 Thermal Bending = 7.969 ksi Pipe A (Thk. Cyl.) 265.6609 Fpress 1987.587 kips Pipe (Matl B) OD I Sflow Phib,t Phib,c 33.5 in 2.75 in 69.9 ksi 1-1- WOL(Matl A) I overlay 0.379962 in Sflow 69.9 ksi Phia,t 1 - Phia,c 1 - Case 1 Case 2 Case 3 3 < Tr - y Crack Above Neutral Axis P = n - y Crack To Neutral Axis or Crack Below Takes Compression 3 > iT - y Crack Below Neutral Axis and Takes no Compression y = half angle up to neutral axis Note that any weld overlay angle a must be above neutral axis and have a half angle < pipe crack half angle Nominal Stresses (Thin Shell Solution) Axial Pr 6.868 ksi Axial Ld 0.000 ksi Total Axial Stress 6.868 ksi Pm Prim. Bend. Stress 20.317 ksi Pb Therm Bend. Stress 7.969 ksi Pe Weld Ovrlay Z Factor Base Metal Z Factor SFm SFb 1 1.21 1.39 1.39 "cntl-shift A <cntl>shift B <cnfl>shift C Size Case 1 Overlay Size Case 2 Overlay Size Case 3 Ovelay For OL Z = 1, Pb,prim = [P'b + (SFb/SFm)Pm - Z M* Pe] / [SFb(I+M* (Z-1))] - Pm For OL Z > 1, Pb,prim = [P'b + (SFb/SFm)Pm]/[SFb{Zol(1-M*)+Zbm(M*))] - Pm - Pe/SFb Case 1 0 < 'n-y 2 03=rr-y 3 3 >uT-y y, degrees y+0 check 26.89 INVALID 35.74 VALID 73.94 VALID Limit Mom Limit Str. in-lb P'b, ksi 95985.9 47.000 85999.6 42.110 79016.9 38.691 M* Pb,prim 0.475 25.36826 Run Case 1 for These Results if F26 = VALID 0.637 20.31659 Results are for Case 2 0.637 18.14691 Run Case 3 for These Results if F28 = VALID Pb' WolZ=1 WolZ>1 25.368 22.634 20.317 18.479 18.147 16.310 Current Results are for Case 2 Weld Overlay Thickness =.38 inch File No.: 0800368.320 Revision: 1 Page A-5 of A-1 F0306-01.

V Structural Integrity Associates, Inc. A.5 LOCATION 2: SSW AT SAFE END SIDE FOR NORMAL/UPSET LOADING CONDITIONS Spreadsheet entitled "DavisBesseDischargeNozzle.xls"

Pressure, Faxial M, prim.

M, therm Weld Overlay Sizing Based on Load Input (Version 1 - 5June08 2255 psi Crack 0 kips a,OL+Lig 0 degrees - half angle 10344.02 in-kips P,pipe 180 degrees - half angle 14519.09 in-kips a/t, pipe 0.75 a/t INPUT is Lt. Green Crack Pressure Fraction Notes: Phi Factors are reduction factors that may be applied to flow stress in each regic Pipe Ligt 0 Crack face pressure fractions are portion of c Pipe Metal Area = 258.3382 Pipe Crk 0 Stresses Using Piping Equations (Info) Pipe Z (shell) = 1991.336 WOL Crk 0 Axial Pressure = 7.081 ksi Shell Theory Z 1991.336 Axial Load = 0.000 ksi Shell Theory A 258.3382 Primary Bending = 5.195 ksi Pipe Z (Thk. Cyl.) 1991.336 Thermal Bending = 7.291 ksi Pipe A (Thk. Cyl.) 258.3382 Fpress 1987.587 kips Pipe (Mat] B) OD t Sflow Phib,t Phib,c 33.5 in 2.667 in 52.3 ksi 1-1- WOL(Matl A) t overlay 0.564475 in Sflow 69.9 ksi Phia,t 1 - Phia,c 1 - Case 1 Case 2 Case 3 3 < T - y Crack Above Neutral Axis 3 Tr - y Crack To Neutral Axis or Crack Below Takes Compression p > 17 - y Crack Below Neutral Axis and Takes no Compression y = half angle up to neutral axis Note that any weld overlay angle a must be above neutral axis and have a half angle < pipe crack half angle Nominal Stresses (Thin Shell Solution) Axial Pr 7.081 ksi Axial Ld 0.000 ksi Total Axial Stress 7.081 ksi Pm Prim. Bend. Stress 5.195 ksi Pb Therm Bend. Stress 7.291 ksi Pe Weld Ovrlay Z Factor Base Metal Z Factor SFm SFb 1 1.68 2.77 2.77 <cntl~shift A <cntl>shift B <cntl>shift C Size Case 1 Overlay Size Case 2 Overlay Size Case 3 Overlay For OL Z = 1, Pb,prim = [P'b + (SFb/SFm)Pm - Z M* Pe] / [SFb(I +M* (Z-1))] - Pm For OL Z > 1, Pb,prim = [P'b + (SFb/SFm)Pm]/[SFb{Zol(1-M*)+Zbm(M*)}] - Pm - Pe/SFb Case 1 3< Tr-y 2 =3=uT-y 3 P3>rT-y y, degrees y+p3 check 32.55 INVALID 41.08 VALID 73.83 VALID Limit Mom Limit Str. in-lb P'b, ksi 95989.5 48.204 86005.7 43.190 80077.9 40.213 M. Pb,prim 0.250 9.031501 Run Case 1 for These Results if F26 = VALID 0.460 5.19358 Results are for Case 2 0.460 4.374972 Run Case 3 for These Results if F28 = VALID Pb' WolZ=1 WolZ>1 9.032 7.344 5.194 4.111 4.375 3.292 Current Results are for Case 2 Weld Overlay Thickness =.5645 inch File No.: 0800368.320 Revision: 1 Page A-6 of A-i l F0306-01

Structural Integrity Associates, Inc. A.6 LOCATION 2: SSW AT SAFE END SIDE FOR FAULTED LOADING CONDITIONS Spreadsheet entitled "DavisBesseDischargeNozzle.xls"

Pressure, Faxial M, prim.

M, therm Weld Overlay Sizing Based on Load Input (Version 1 - 5June08) 2255 psi Crack 0 kips aOL+Lig 0 degrees - half angle 36816.33 in-kips 03,pipe 180 degrees - half angle 14519.09 in-kips a/t, pipe 0.75 a/t INPUT is Lt. Green Crack Pressure Fraction Notes: Phi Factors are reduction factors that may be applied to flow stress in each regic Pipe Ligt 0 Crack face pressure fractions are portion of c Pipe Metal Area = 258.3382 Pipe Crk 0 Stresses Using Piping Equations (Info) Pipe Z (shell) = 1991.336 WOL Crk 0 Axial Pressure = 7.081 ksi Shell Theory Z 1991.336 Axial Load = 0.000 ksi Shell Theory A 258.3382 Primary Bending = 18.488 ksi Pipe Z (Thk. Cyl.) 1991.336 Thermal Bending 7.291 ksi Pipe A (Thk. Cyl.) 258.3382 Fpress 1987.587 kips Pipe (Mat] B) OD t Sflow Phib,t Phib,c WOL(Matl A) 33.5 in 2.667 in 52.3 ksi 1-1- t overlay Sflow Phia,t Phia,c Case 1 Case 2 Case 3 0.593945 in 69.9 ksi 1-1- [3 < T - y Crack Above Neutral Axis 3= Tr - y Crack To Neutral Axis or Crack Below Takes Compression P >,-r - y Crack Below Neutral Axis and Takes no Compression y = half angle up to neutral axis Note that any weld overlay angle a must be above neutral axis and have a half angle < pipe crack half angle Nominal Stresses (Thin Shell Solution) Axial Pr 7.081 ksi Axial Ld 0.000 ksi Total Axial Stress 7.081 ksi Pm Prim. Bend. Stress 18.488 ksi Pb Therm Bend. Stress 7.291 ksi Pe Weld Ovday Z Factor Base Metal Z Factor SFm SFb 1 1.68 1.39 1.39 'ccnbtshift A <cntl~shift B <cjitl>shift C Size Case 1 Overlay Size Case 2 Overlay Size Case 3 Overlay For OL Z = 1, Pb,prim = [P'b + (SFb/SFm)Pm - Z M* Pe] / [SFb(I+M* (Z-1))] - Pm For OL Z > 1, Pb,pdm = [P'b + (SFb/SFm)Pm]/[SFb{Zol(1-M*)+Zbm(M*)}] - Pm - Pe/SFb Case 1 1< Tr-Y 2 =TT -y 3 I> 1T-Y y, degrees y+[3 check 33.27 INVALID 41.92 VALID 74.28 VALID Limit Mom Limit Str. in-lb P'b, ksi 99222.0 49,827 89102.4 44.745 82639.4 41.499 M. Pb,prim 0.233 26.49526 Run Case 1 for These Results if F26 = VALID 0.447 18.48826 Results are for Case 2 0.447 16.69775 Run Case 3 for These Results if F28 = VALID Pb'-- WolZ=1 WolZ>1 26.495 23.021 18.488 16,265 16.698 14.474 Current Results are for Case 2 Weld Overlay Thickness =.5939 inch File No.: 0800368.320 Revision: 1 Page A-7 of A-1 F0306-01

V Structural Integrity Associates, Inc. A.7 LOCATION 1: NOZZLE AT SSW INTERFACE FOR NORMAL/UPSET LOADING CONDITIONS Spreadsheet entitled "DavisBesseDischargeNozzle.xls"

Pressure, Faxial M, prim.

M, therm Weld Overlay Sizing Based on Load Input (Version 1 - 5June08 2255 psi Crack 0 kips a,OL+Lig 0 degrees - half angle 10344.02 in-kips P,pipe 180 degrees - half angle 14519.09 in-kips aft, pipe 0.75 alt INPUT is Lt. Green Crack Pressure Fraction Notes: Phi Factors are reduction factors that may be applied to flow stress in each regic Pipe Ligt 0 Crack face pressure fractions are portion of c Pipe Metal Area 295.0272 Pipe Crk 0 Stresses Using Piping Equations (Info) Pipe Z (shell) = 2300.401 WOL Crk 0 Axial Pressure = 6.403 ksi Shell Theory Z 2300.401 Axial Load = 0.000 ksi Shell Theory A 295.0272 Primary Bending = 4.497 ksi Pipe Z (Thk. Cyl.) 2300.401 Thermal Bending = 6.312 ksi Pipe A (Thk. Cyl.) 295.0272 Fpress 2071.518 kips Pipe (Matl B) OD t Sflow Phib,t Phib,c WOL(Matl A) 3.011 in 52.2 ksi 1-1- Case 1 Case 2 Case 3 t overlay Sflow Phia,t Phia,c 0.52869 in 69.9 ksi 1-1- < 7T - y Crack Above Neutral Axis p = Tr - y Crack To Neutral Axis or Crack Below Takes Compression p > rr - y Crack Below Neutral Axis and Takes no Compression y = half angle up to neutral axis Note that any weld overlay angle a must be above neutral axis and have a half angle < pipe crack half angle Nominal Stresses (Thin Shell Solution) Axial Pr 6.403 ksi Axial Ld 0.000 ksi Total Axial Stress 6.403 ksi Pm Prim. Bend. Stress 4.497 ksi Pb Therm Bend. Stress 6.312 ksi Pe Weld Ovrlay Z Factor Base Metal Z Factor SFm SFb 1 1.69 2.77 2.77 <cntI>slhift A <cntI~shift C Size Case 1 Overlay Size Case 2 Overlay Size Case 3 Overlay For OL Z = 1, Pb,prim = [P'b + (SFb/SFm)Pm - Z M* Pe] / [SFb(I+M* (Z-1))] - Pm For OL Z > 1, Pb,prim = [P'b + (SFb/SFm)Pm]/[SFb{Zol(1-M*)+Zbm(M*)}] - Pm - Pe/SFb Case 1 3<rrT-y 2 3=rr-y 3 P >TT-y y, degrees y+13 check 31.28 INVALID 39.72 VALID 74.49 VALID Limit Mom Limit Str. in-lb P'b, ksi 102537.4 44.574 91385.0 39.726 85306.5 37.083 M* Pb,prim 0.304 7.845831 Run Case 1 for These Results if F26 = VALID 0.506 4.496487 Results are for Case 2 0.506 3.789394 Run Case 3 for These Results if F28 = VALID Pb' WolZ=1 WolZ>1 7.846 6.534 4.496 3.662 3.789 2.955 Current Results are for Case 2 Weld Overlay Thickness =.5287 inch File No.: 0800368.320 Page A-8 of A-Il Revision: 1 F0306-01I

V Structural Integrity Associates, Inc. A.8 LOCATION 1: NOZZLE AT SSW INTERFACE FOR FAULTED LOADING CONDITIONS Spreadsheet entitled "DavisBesseDischargeNozzle.xls" Weld Overlay Sizing Based on Load Input (Version 1 - 5June08)

Pressure, 2255 psi Crack Faxial 0 kips a,OL+Lig 0 degrees - half angle M, prim.

36816.33 in-kips P3,pipe 180 degrees - half angle M, therm 14519.09 in-kips a/t, pipe 0.75 a/t Fpress 2071.518 kips INPUT is Lt. Green Crack Pressure Fraction Notes: Phi Factors are reduction factors that may be applied to flow stress in each regic Pipe Ligt 0 Crack face pressure fractions are portion of c Pipe Metal Area = 295.0272 Pipe Crk 0 Stresses Using Piping Equations (Info) Pipe Z (shell) = 2300.401 WOL Crk 0 Axial Pressure = 6.403 ksi Shell Theory Z 2300.401 Axial Load = 0.000 ksi Shell Theory A 295.0272 Primary Bending = 16.004 ksi Pipe Z (Thk. Cyl.) 2300.401 Thermal Bending = 6.312 ksi Pipe A (Thk. Cyl.) 295.0272 Pipe (Matl B) OD t Sflow Phib,t Phib,c 3.011 in 52.2 ksi 1-1- WOL(Matl A) t overlay 0.549181 in Sflow 69.9 ksi Phia,t 1 - Phia,c 1 - Case 1 Case 2 Case 3 3 < Tr - y Crack Above Neutral Axis 3 = Tr - y Crack To Neutral Axis or Crack Below Takes Compression > Tn - y Crack Below Neutral Axis and Takes no Compression y = half angle up to neutral axis Note that any weld overlay angle a must be above neutral axis and have a half angle < pipe crack half angle Nominal Stresses (Thin Shell Solution) Axial Pr 6.403 ksi Axial Ld 0.000 ksi Total Axial Stress 6.403 ksi Pm Prim. Bend. Stress 16.004 ksi Pb Therm Bend. Stress 6.312 ksi Pe Weld Ovrlay Z Factor Base Metal Z Factor SFm SFb 1 1.69 1.39 1.39 'cntIrshift A <cnt~sift C Size Case 1 Overlay Size Case 2 Overlay Size Case 3Overlay For OL Z = 1, Pb,prim = [P'b + (SFb/SFm)Pm - Z M* Pe] / [SFb(I+M* (Z-1))] - Pm For OL Z > 1, Pb,prim = [P'b + (SFb/SFm)Pm]/[SFb{Zol(1-M*)+Zbm(M*))] - Pm - Pe/SFb Case 1 13<Tr-y 2 13= r-y 3 P>rr-y y, degrees y+l3 check 31.76 INVALID 40.29 VALID 74.79 VALID Limit Mom Limit Str. in-lb P'b, ksi 104873.2 45.589 93630.9 40.702 87147.3 37.884 M* Pb,prim 0.290 22.90374 Run Case 1 for These Results if F26 = VALID 0.496 16.00399 Results are for Case 2 0.496 14.49355 Run Case 3 for These Results if F28 = VALID Pb'-- WolZ=1 WolZ>1 22.904 20.219 16.004 14.300 14.494 12.790 Current Results are for Case 2 Weld Overlay Thickness =.5492 inch File No.: 0800368.320 Revision: 1 Page A-9 of A-1 F0306-01I

V Structural Integrity Associates, Inc. A.9 OUTER DIAMETER CALCULATIONS FOR THE NOZZLE 0 006 Diameter =28.166 in g File No.: 0800368.320 Revision: 1 Page A-10 of A-1 1 F0306-01

V Structural Integrity Associates, Inc. A.10 OUTER DIAMETER CALCULATIONS FOR THE ELBOW 1.0.50 CV') '7.50' Diameter = 28 in T File No.: 0800368.320 Revision: 1 Page A-1I of A-I F0306-01'

V Structural Integrity Associates, Inc. Appendix B WELD OVERLAY SIZING METHODOLOGY (13 PAGES) Table of Contents B.1 INTRODUCTION/OBJECTIVE................................... B-2 B.2 TECH N ICA L APPROA CH...................................................................................... B-3 B2.3.1 Case 1 - Cracking Above Neutral Axis.......................................................... B-6 B2.3.2 Case 2 - Cracking Below Neutral Axis - Crack in Compression.................. B-8 B2.3.3 Case 3 - Crack Below Neutral Axis - No Crack Compression..................... B-9 B.3 ASSUMPTIONS / DESIGN INPUTS..................................................................... B-12 B.4 SPREADSHEET DEVELOPMENT....................................................................... B-12 B.5 CONCLUSIONS AND DISCUSSIONS................................................................. B-12 B.6 R E FE R E N C E S........................................................................................................ B -13 List of Figures BI DEFINITION OF CRACKED SECTION................................................................. B-2 File No.: 0800368.320 Revision: 1 Page B-1 of B-13 F0306-O1RO

V Structural Integrity Associates, Inc. B.1 INTRODUCTION/OBJECTIVE For a weld overlaid piping geometry, the weld overlay material and the base metal material may have different material strength and toughness. Since the weld overlay is installed at a slightly larger diameter than the base metal, it has more area per unit circumference and thickness than the base metal. The concept of the two-material overlay was described in a 2006 Pressure Vessel and Piping Conference paper [B 1]. Figure B I shows the geometry to be evaluated. The objective of this calculation is to develop a spreadsheet that may be used to size weld overlays using the two-material concept. The spreadsheet can then be used for plant-specific weld overlay design applications. Tension W b1 abase 0601 ORO Figure B1 Definition of Cracked Section File No.: 0800368.320 Revision: 1 Page B-2 of B-13 F0306-O1RO

V Structural Integrity Associates, Inc. B.2 TECHNICAL APPROACH Appendix C of Section XI of the ASME Code [B2] has a method for evaluating flawed piping using net section collapse limit load methods. The methodology is based on a single material thin cylinder and can be used to determine the critical through-wall flaw size for an overlaid pipe. A modified approach is developed herein based on similar limit load methods, but has some additional considerations:

1. The effect of having two separate materials is considered. Whereas the piping forces/moments in the original piping analysis are based on the un-overlaid pipe geometry, the weld overlay material, at a slightly larger radius, provides more material per unit circumference and thickness for resisting applied loads.
2. The model is developed for a partial thickness (to full thickness) crack in the base (pipe or weld) material, and will also consider a through-wall crack in the weld overlay and underlying pipe ligament to facilitate evaluation of through-wall flaws. The latter feature for considering a through-wall flaw is an extension from previous work that considered critical flaw sizing for a leak-before-break analysis.
3.

The evaluation method allows a reduction in the strength of the base material to be considered, since this material may not have the toughness as the overlay material. The strength reduction factor may be separately applied to the material in tension and that in compression, with the idea that ductile tearing might not be possible for the material in compression.

4. Pressure may be applied on the crack face. The pressure produces an additional axial force and bending moment at the section. An applied pressure reduction factor is defined separately for both the base material crack and the overlay crack, allowing consideration of pressure drop across the crack for through-wall flaws. The consideration of the crack face pressure allows the pressure force membrane stresses for evaluation to be based on the insider diameter of the piping, not using the standard ASME Section III Code equation based on the section outside diameter.
5. The model allows for the arbitrary definition of the crack length for the weld overlay and for the base material. The length of the base metal crack can be any length. The region below the neutral axis can be evaluated with or without the ability to take crack face compression.

(If compression is not assumed, then applied crack pressure will also act on the crack face. If the crack can take compression, then pressure is not assumed to act coincidentally.)

6. The safety factors of ASME Section XI may be included in determining the relationship between the actual applied loads and the limit load state.
7. The low toughness for the weld overlay material and the base material may be incorporated considering the inclusion of thermal stresses in the allowable stress equations by inputting Z factors for the weld overlay and base material that are greater than 1.0.

File No.: 0800368.320 Page B-3 of B-13 Revision: 1 F0306-O1RO

V Structural Integrity Associates, Inc. B2.1 Definitions For purposes of defining parameters, the weld overlay is considered to be material A and the base material (original pipe or weld - also the material remote from the overlay) is considered to be material B. The following nomenclature is used in the equations for net section collapse: a = half through-wall (TW) crack angle in weld overlay and underlying base material ligament S= half part-wall crack angle in original pipe or weld (can be different than weld overlay) (like 0 in ASME Section XI, Appendix C evaluation methods) - must be greater than or equal to the angle a 7 angle to neutral compression/tension axis from opposite side of the pipe (like P3 in ASME Section XI, Appendix C) = angle to neutral compression/tension axis from top of the pipe at crack center = r-7 ra = mean radius of weld overlay rb = mean radius of original pipe rbc = mean radius of crack in original pipe rbm = mean radius of base material remaining over crack ri inside radius of original pipe r = radius in a general sense ta = thickness of weld overlay tb = thickness of original pipe a = crack depth in original pipe tbm = thickness of base material remaining over crack = tb - a t = thickness in a general sense Ufa = flow stress of weld overlay Gfb = flow stress of original pipe o stress in a general sense Ota, (Dtb = factor to be applied to flow stress of weld overlay or original piping material for the tensile region to account for reduced toughness and consideration of thermal stresses Oca, (cDb = factor to be applied to flow stress of weld overlay or original piping material for the compressive region Xa = factor to multiply the pressure on the crack face for the weld overlay Xb factor to multiply the pressure on the crack face for the base material crack XH = factor to multiply the pressure on ligament crack adjacent to overlay crack Pm axial stress in original pipe remote from weld due to pressure and axial load = [P x 7t ri2 + F]/(2a rb t) P = pipe pressure (with same units as stress) F = axial pipe load P'b = limit bending moment stress for the unflawed original pipe (corresponding moment is M' = P'b x (7t rb2 tb) Pb = piping primary bending stress Pe = piping thermal expansion stress Z = Z-factor defined by ASME Section XI Appendix C File No.: 0800368.320 Page B-4 of B-13 Revision: 1 F0306-O1RO

V Structural Integrity Associates, Inc. SFm = Safety factor defined by ASME Section XI Appendix C for membrane stresses SFb = Safety factor defined by ASME Section XI Appendix C for bending stresses Note that some additional terms are defined where used. B2.2 Force and Moment Integration For any section of the piping, the axial force integration is: Faxial = f2 dO =crt -01) The moment integration is: M = fIarg 2 tcos0d0 = arr2 t(sinO0 - sin 0,) Although stress is used in the above equations, the stress term may be either the stress acting in the material or the pressure acting on a crack face. B2.3 Evaluation of Forces, Moments and Neutral Axis The most simple case is that of crack angles in the original pipe/base material/weld (P3) and WOL (c) that are less than the angle to the neutral axis (y from bottom of pipe). Note that in the following equations, all forces and moments are computed for 2 of the pipe section for an angle between 0 and 7r, where the angles are measured from the top of the pipe as shown in Figure B 1. Due to symmetry, the total forces and moments would be twice those computed for the 1/2 pipe used in the analysis for a symmetrically cracked section. R = remote force = Fp + Fa Fp = remote force due to pressure (divided by 2) Fa = remote axial force (divided by 2) P = pressure Fp , based on the original pipe remote from the weld overlay 2 There are also axial forces on the cracks due to crack face pressure. FCFP = fa (X + fb f3 where fa = q, rata q'a = crack face pressure = Xa P File No.: 0800368.320 Page B-5 of B-13 Revision: 1 F0306-O1RO

Structural Integrity Associates, Inc. Xa = crack face pressure knockdown factor for WOL fb =q, rbCa qb = Xb P Xb = crack face pressure knockdown factor for base material Similar equations can be derived for the moment due to crack face pressure. For limit load conditions, the axial force equations are used with the stresses at tensile flow stress above the neutral (tension/compression transition) axis and with stresses at compressive yield below the neutral axis. B2.3.1 Case 1 - Cracking Above Neutral Axis First, the problem will be solved for the case where the region below the neutral axis is uncracked. The following breaks the pipe up into a number of different areas. In each region, there will be a force equal to the area times the stress (or applied pressure). The forces due to tensile stress at the crack location will be taken as positive and equated to the remotely applied forces. The location of the neutral axis can be found such that sum of the forces on the half pipe section is equal to the sum of the remote forces (divided by two) as determined above. The angle from the top of the pipe to the neutral axis will be defined as xy (= nt - y). Specific regions can be defined and evaluated as follows: o Region A: Weld overlay above the neutral axis o Force = GA (V -a), where GA = cfa Ot, ra t, o Moment = G'A (sin V' -sin a) where G'A = afa cDta ra2 ta 0 Region B: Pipe above the neutral axis beyond the crack angle o Force = GB (x' -13), where GB = afb.*tb rb tb o Moment = G'B (sin V -sin 13) where G'B = Y Dtb rb2 tb o Region C: Ligament over the crack in pipe o Force = Gc (13-a), where Gc = cfb Ftb rbm tbm o Moment = G'c (sin 13-sin a) where G'C = am (Dtb rbm tbm o Region D: Area of pipe that is cracked o Force = GD (13), where GD = - P Xb rbc a 2 o Moment = G'D (sinp3) where G'D = - P Xb rbc a File No.: 0800368.320 Page B-6 of B-13 Revision: 1 F0306-01RO

V Structural Integrity Associates, Inc. Region E: Weld overlay below the neutral axis o Force = GE(it - W), where GE = - Ufa Lca rata o Moment = G'E (-sin y) where G'E =- Ofa Ozca ra2 ta Region F: Uncracked pipe below the neutral axis o Force = GF(7r - i), where GF = - Gfb (Icb rb tb o Moment = G'F (-sin y) where G'F = - cYfb (Dcb rb tb o Region G: Cracked region in the weld overlay above the neutral axis (assumed through-wall) o Force = GG (a), where Ga = -P Xa ra ta o Moment = G'G (sin a) where G'A = -P Xa ra2 ta

  • Region H: Through-wall crack in ligament over the larger crack in the base material o

Force = GH (13-a), where GH = -P XH rbm tbm o Moment = G'H (sin 13-sin a) where G'H = -P XH rbm2 tbm R = GA (W -a) + GB ( -13) + Gc (13-a) + GD (13) + GE (7r -W) + GF (7 )- + GG (a) + GH(a) = (GA +GB-GE-GF)'+{-GAa-GB13+Gc(3-a) +GD 13+ GE 7r + GF 71 + GG a +GH a} or w = [R -{-GA a - GB 13+ Gc (13 - a) +GD 13+ GE t + GF 7r + GG a + GH a}] / (GA+GB-GE-GF) The limit bending moment can be determined by integrating the force distribution with compression below the neutral axis and tension above it by summing the above equations. Mr-case 1 = remote applied moment (on 1/2 of pipe) at limit load = G'A (sin y -sin a) + G'B (sin pV -sin 13) + G'c (sin 13 - sin a) + G'D (sin 13) + G'E (-sin V) + G'F (-sin V) + G'G (sin a) +G'H (sin a) File No.: 0800368.320 Revision: 1 Page B-7 of B-13 F0306-O1RO

Structural Integrity Associates, Inc. B2.3.2 Case 2 - Cracking Below Neutral Axis - Crack in Compression This solution is for the case where the crack extends either to or into the region below the neutral axis, and applies to the case where a crack extending below the neutral axis can take compression. In this case, the crack effectively stops at the neutral axis and pressure is not considered to be additive to the compression acting at the crack below the neutral axis. This case can be used for design of full structural overlays where the original pipe/weld is assumed to be cracked completely around the circumference. Specific regions can be defined and evaluated as follows: Region A: Weld overlay above the neutral axis (same as above) o Force = GA (xV -a), where GA = Ofa (Dta ra ta o Moment = G'A (sin v -sin a) where G'A = ofa (Dta ra2 ta o Region B: Pipe above the neutral axis beyond the crack angle (does not exist so force and moment are zero o Force = 0 o Moment = 0

  • Region C: Ligament over the crack in pipe o Force = Gc (xV - a), where Gc = Gfb I)tb rbm tbm o Moment = G'c (sin xV - sin a) where G'c = Yfb cItb rbm2 tbm Region D: Area of pipe that is cracked o Force = GD (V), where GD = - P Xb rbc a o Moment = G'D (sinp) where G'D = - P Xb rbc2 a Region E: Weld overlay below the neutral axis (same as above) o Force = GE (E -W), where GE = - afa (Dca ra ta o Moment = G'E ( -sin xV) where G'E = - *fa (Ica ra2 ta o

Region F: Uncracked pipe (or crack taking compression) below the neutral axis (same as above) o Force = GF (7 -W), where GF = - Gfb (cb rb tb o Moment = G'F (-sin V) where G'B = - Fb (Dcb rb2 tb o Region G: Cracked region in the weld overlay always assumed to be above the neutral axis (assumed through-wall - same as the previous case) o Force = GG (a), where Ga = -P Xa ra ta o Moment = G'G (sin a) where G'A = -P Xa ra2 ta Region H: Through-wall crack in ligament over the larger crack in the base material o Force = G1- (P3-a), where GH = -P XH rbm tUrn o Moment = G'H (sin P3-sin a) where G'H = -P XH rIbm2 tbm R = GA (W -a) + GB (0) + Gc (V -a)+ GD (V) + GE (r -) + GF (,K -x) + GG (a) + GH(a) File No.: 0800368.320 Page B-8 of B-13 Revision: 1 F0306-OIRO

V Structural Integrity Associates, Inc. = (GA+Gc+GD-GE-GF)WV+(-GAa -Gca+GE E+GF7t+GGa+GH l) or xV = [R -(-GAa-Gca+GE r+GF r+GGa+GHcL)]/(GA+Gc+GD-GE-GF) The limit bending moment can be determined by integrating the force distribution with compression below the neutral axis and tension above it by summing the above equations. Mr-case 2 = remote applied moment (on whole pipe) at limit load G'A (sin pV -sin a) + G'c (sin p - sin a) + G'D sin pV + G'E (-sin xV) + G'F (-sin p) + G'G (sin a) + G'H (sin a) B2.3.3 Case 3 - Crack Below Neutral Axis - No Crack Compression This solution applies to the case where the crack extends below the neutral axis and the crack face is not capable of taking compression. This is not the approach taken in ASME Section XI Appendix C, where the equations were derived assuming that the material below the neutral axis would close such that the crack face could take compression. In this case, the crack is assumed to be loaded with pressure since crack closure is not assumed. Specific regions can be defined and evaluated as follows: o Region A: Weld overlay above the neutral axis (identical to above) o Force = GA (pV -a), where GA =fa (YFta ra ta o Moment = G'A (sin N' -sin a) where G'A = c(fa (Dta ra2 ta " Redefined Region B: Pipe ligament below the neutral axis to the crack angle o Force = GB (P3 - yj), where GB = - fib 4)cb rbm tbm o Moment = G'B (sin N' -sin P3) where G'B = -(jib 4)cb rbm2 tbm o Region C: Ligament over the crack in pipe above the neutral axis o Force = Gc (y - a), where Gc = (ib (IDtb rbm tbm o Moment = G'c (sin p - sin a) where G'c = cfb (IDtb rbm2 tbm " Region D: Area of pipe that is cracked o Force = GD (P3), where GD = - P Xb rbc a o Moment = G'D (sinp3) where G'D = - P Xb rbc2 a " Redefined Region E: Weld overlay below the neutral axis o Force = GE (7t - k), where GE= (af, (Dca rata o Moment = G'E ( -sin W) where G'E =- fa (Da ra ta File No.: 0800368.320 Page B-9 of B-13 Revision: 1 F0306-OIRO

V Structural Integrity Associates, Inc.

  • Redefined Region F: Uncracked pipe beyond crack tip o Force = GF (7 - P3), where GF = -

Ifb (cb rb tb o Moment = G'F (-sin P3 ) where G'B = - Yfb ccb rb2 tb o Region G: Cracked region in the weld overlay above the neutral axis (assumed through-wall) o Force = GG (a), where Ga = -P Xa ra ta o Moment = G'G (sin a) where G'A = -P Xa ra2 ta o Region H: Through-wall crack in ligament over the larger crack in the base material o Force = GH (j3-a), where Gn = -P XH rbrn tbm o Moment = G'H (sin P3-sin a) where G'H = -P XH rbm2 tbm R = GA(W-a)+GB(P-p)+Gc(i-a)+GD(f3)+GE(ir-W)+GF(Ir-t3)+GG(a)+GH(a) = (GA-GB+Gc-GE)XJ + {- GA a - Gc (a) + GB f3 + GD f3 + GE 7 + GF (7r - f3) + GG a + GH a} or = [R - - GA a - Gc a + GB P + GD P + GE 7L + GF (I - f3) + GG a + GH a } ] / (GA - GB + Gc - GE) The limit bending moment can be determined by integrating the force distribution with compression below the neutral axis and tension above it by summing the above equations. Mr-case 3 = remote applied moment (on whole pipe) at limit load = G'A (sin xV - sin a) + G'B (sin p - sin P3) + G'c (sin p - sin a) + G'D sin P3 + G'E (-sin p) + G'F (-sin P3) + G'G (sin a) + G'H (sin a) B2.4 Determination of Limit Stresses The limit stress, representing the thin-shell approximation stress in the uncracked pipe, can be computed from Mr Pb 2 P 7rr b tb The remote limit bending stress based on piping equations could be calculated using the ASME Code formula for bending stress in a pipe. This would represent the extreme fiber stress in the pipe section: pMr File No.: 0800368.320 Page B-10 of B-13 Revision: 1 F0306-OIRO

V Structural Integrity Associates, Inc. where: Mr = remote applied load on the pipe (entire cross section) at limit load Z = section modulus of the piping. If the input to a problem is the stresses based on piping equations, then this same equation can be re-written to compute the applied moment given the stress. The overlay material is generally a very high toughness material such that the thermal expansion stresses would not have to be considered in determining critical flaw size. The underlying material may have low toughness. The PVP paper [1] describes how net section plastic collapse analysis may be conducted for a two layer configuration with both low toughness and high toughness materials. Pb = [P'b + (SFb/SFm) Pm - ZM*Pe] /{SFb[l + M*(Z-1)]} - Pm where: Pb = primary bending stress Pm = primary membrane stress Pe = thermal expansion bending stress Z = Z-factor for correcting for low toughness material M* = ratio of tension region material moment due to base material divided by the total moment for tensile material (See discussion below for redefinition.) SFb = Bending Safety Factor for Service Level SFm= Membrane Safety Factor for Service Level With this approach, if it is assumed that the entire base material is cracked above the neutral axis (such as one would do with a full structural overlay), then M* = 0 and the equation collapses back to the form for high toughness material. If it is assumed that there is no overlay material, then M* = 1.0, and the equation becomes that for a low-toughness material where the complete effects of the thermal expansion moment must be included in the evaluation. This is a convenient method for "interpolating" to determine the contribution of thermal expansion stress that should be considered of the overlaid section. Experience with applying the approach defined herein showed that determination of the M* ratio using the moment contributions was somewhat unstable for some configurations. The portion of the tensile region that is below the pipe centerline contributes a moment with a negative sign. If the moment contribution below the pipe centerline becomes larger than that from above, the sign of the moment is negative. In this case, the ratio for M* above becomes highly unstable when the moment nears zero. As an alternative, M* is re-defined based on the ratio of the tensile loads. Tensile load due to base material in tensile region (above neutral axis) M* (modified) =........... Total tensile load for tensile region (above neutral axis) Application of this modified ratio showed that it was not much different than the ratio based on the tensile moment, when there was a net positive moment in both the base material and weld overlay material. Thus, File No.: 0800368.320 Page B-1I of B-13 Revision: 1 F0306-O1RO

V Structural Integrity Associates, Inc. this modified definition will be use for combining the solutions for high-toughness and low-toughness materials. A similar equation can be derived if one must assume that the weld overlay is not a high toughness material and must have a Z-factor applied. In this case, the complete unfactored thermal expansion moment must be considered in determining the allowable bending stress. The resulting equation is Pb = [P'b + (SFb/SFm) Pm] /{SFb[Za (1 - M*) + Zb M*]} - Pm - Pe/SFb where: Za = Z-factor for the weld overlay Zb = Z-factor for the original pipe/weld material These equations also yield the correct solutions for the no-overlay and no-base material cases described above. B.3 ASSUMPTIONS / DESIGN INPUTS There are none. This methodology is a methods development evaluation only. Typical properties are used. B.4 SPREADSHEET DEVELOPMENT Two spreadsheets are developed. One allows input of the basic loads as pressure, axial force, and moments. The second allows input of stresses calculated using the standard equations for piping analysis [B3]. B.5 CONCLUSIONS AND DISCUSSIONS The spreadsheets developed allow for rapid solution of weld overlay thickness using shell equations for net section collapse. The spreadsheets allow for a technique of analysis that is really not needed, namely the application of separate stress reduction factors for the tensile and compressive regions. The thought behind these stress reduction factors was that low toughness materials could not tear in compression. Thus, instead of using Z-factors that apply a common knockdown factor to both the tensile and compressive regions, a separate factor could be applied to just the tensile region such the results of EPFM J-T analysis could be calibrated with a stress reduction factor instead of a Z-factor. Since this technique has not received ASME Code Committee or regulatory review, it is recommended that these factors be kept as 1.0 and the Z-factor approach be used. File No.: 0800368.320 Revision: 1 Page B-12 ofB-13 F0306-01RO

C Structural Integrity Associates, Inc. B.6 REFERENCES B 1.

Deardorff,

A, et.al., "Net Section Plastic Collapse Analysis of Two-Layered Materials and Application to Weld Overlay Design," PVP2006-ICPVT1 1-93454, ASME PVP Conference 2006, SI File No. MILL-i IQ-207. B2. ASME Boiler and Pressure Vessel Code, Section XI, Rules for Inservice Inspection of Nuclear Power Plant Components (various Editions and Addenda). B3. ASME Boiler and Pressure Vessel Code, Section III, Subsection NB - Class 1 Components (various Editions and Addenda). File No.: 0800368.320 Revision: 1 Page B-13 of B-13 F0306-O1RO}}

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