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Calculation 32-9222042-000, Enclosure Relief Request 52 Proposed Alternative in Accordance with 10 CFR 50.55a(a)(3)(i) ATTACHMENT 1 ASME Section Xl End of Life Analysis of PVNGS Unit 3 RV BMI Nozzle Repair 0402-01-FOl (Rev. 018, 01/30/2014) A CALCULATION SUMMARY SHEET (CSS) AREVA Document No. 32 - 9222042 - 000 Safety Related: MYes El No Title ASME Section Xl End of Life Analysis of PVNGS3 RV BMI Nozzle Repair (Non-Proprietary) PURPOSE AND SUMMARY OF RESULTS: AREVA Inc. proprietary information in the document is indicated by pairs of braces "[I". PURPOSE: Visual inspection of the reactor vessel Bottom Mounted Instrument (BMI) nozzles at Palo Verde Nuclear Generation Station, Unit 3 (PVNGS3), in October of 2013 revealed the presence of boric acid crystals on the outside of the lower head at BMI nozzle #3. Boric acid deposits at the gap between the nozzle and head indicate leakage of primary water through cracks in the J-groove weld and the nozzle wall. AREVA performed a half nozzle repair of nozzle #3 that maintained the full incore instrumentation functionality of the nozzle. This repair, described in References [1] and [2], moves the primary pressure boundary nozzle weld from the inside of the vessel to a weld pad on the outside surface. This calculation evaluates fatigue crack growth of postulated radial-axial flaws in the existing J-Groove weld and buttering of PVNGS BMI nozzle #3 until the plant license expiration in 2047 (Reference [15]). Acceptance of each postulated flaw is determined based on available fracture toughness or ductile tearing resistance using the safety factors outlined in Table 1-1. SUMMARY OF RESULTS: A fatigue crack growth and fracture mechanics evaluation of postulated radial-axial flaws in the existing J-Groove weld and buttering of PVNGS BMI nozzle #3 was performed. Based on a combination of linear elastic and elastic- plastic fracture mechanics the postulated flaws are shown to be acceptable for the remaining life utilizing the safety factors in Table 1-1, and the lower bound J-R Curve from Regulatory Guide 1.161. This is the Non-Proprietary version of 32-9215090-001. The following table summarizes the total pages contained in this document. IPagesSection 142IMain Bod 124Aendix A Apendix24 B 190Total THE DOCUMENT CONTAINS ASSUMPTIONS THAT SHALL BE THE FOLLOWING COMPUTER CODES HAVE BEEN USED IN THIS DOCUMENT: VERIFIED PRIOR TO USE CODENERSION/REV CODENERSION/REV E]Yes ANSYS 14.5.7 / Windows 7 0No Enclosure Attachment 1 Page 1 of 90 A 0402-01-FO1 (Rev. 018, 01/30/2014) AREVA Document No. 32-9222042-000 ASME Section XI End of Life Analysis of PVNGS3 RV BMI Nozzle Repair (Non-Proprietary) Review Method: IV Design Review (Detailed Check) E Alternate Calculation Signature Block PIR/A Name and Title and Pages/Sections (printed or typed) Signature LP/LR Date Prepared/RevlewedlApproved All Tom Riordan P All Engineer Ill Doug Killian R All Technical Consultant *--4 Tim Wiger A _ / All Engineering . .q' Manager L Note: P/R/A designates Preparer (P), Reviewer (R), Approver (A); LP/LR designates Lead Preparer (LP), Lead Reviewer (LR) Project Manager Approval of Customer References (N/A if not applicable) Name Title (printed or typed) (printed or typed) Signature Date Maya Chandrasheklhar Project Manager 4t/1 '/,i' j Mentoring Information (not required per 0402-01) Name Title Mentor to: (printed or typed) (printed or typed) (PIR) Signature Date N/A Enclosure Attachment 1 Page 2 A AREVA Document No. 32-9222042-000 ASME Section XI End of Life Analysis of PVNGS3 RV BMI Nozzle Repair (Non-Proprietary) Record of Revision Revision Pages/Sections/Paragraphs No. Changed Brief Description / Change Authorization 000 All Original Release Enclosure Attachment 1 Page 3 A AR EVA Document No. 32-9222042-000 ASME Section XI End of Life Analysis of PVNGS3 RV BMI Nozzle Repair (Non-Proprietary) Table of Contents Page SIG NATURE BLOCK ................................................................................................................................ 2 RECO RD O F REVISIO N .......................................................................................................................... 3 LIST O F TABLES ..................................................................................................................................... 6 LIST O F FIG URES ................................................................................................................................... 8 1.0 PURPOSE ..................................................................................................................................... 9 2.0 ANALYTICAL M ETHODOLO GY ............................................................................................ 10 2.1 Stress Intensity Factor Solution .................................................................................................. 10 2.1.1 Plastic Zone Correction ............................................................................................... 11 2.2 Fatigue Crack Growth ..................................................................................................................... 15 2.3 Linear Elastic Fracture Mechanics ............................................................................................. 16 2.4 Elastic-Plastic Fracture Mechanics ........................................................................................... 16 2.4.1 Screening Criteria ....................................................................................................... 16 2.4.2 Flaw Stability and Crack Driving Force ........................................................................ 16 3.0 ASSUM PTIONS .......................................................................................................................... 19 3.1 Unverified Assumptions ................................................................................................................... 19 3.2 Justified Assumptions ...................................................................................................................... 19 3.3 Modeling Simplifications ............................................................................................................ 19 4.0 DESIG N INPUTS ........................................................................................................................ 20 4 .1 G e o m e try ......................................................................................................................................... 2 0 4 .2 Ma te ria ls .......................................................................................................................................... 2 1 4.3 Transients ........................................................................................................................................ 25 4.4 Finite Element Model ....................................................................................................................... 26 4.4.1 Boundary Conditions .................................................................................................. 26 4.4.2 Applied Stresses ......................................................................................................... 26 5.0 CO M PUTER FILES ..................................................................................................................... 28 5.1 Software .......................................................................................................................................... 28 5.2 Computer Files ................................................................................................................................ 28 6.0 CALCULATIO NS ........................................................................................................................ 34 6.1 Stress Intensity Factors ................................................................................................................... 34 6.2 Fatigue Crack Growth .................. ........................................ ................................................. 34 6.3 LEFM Evaluation ............................................................................................................................. 36 6.4 EPFM Evaluations ........................................................................................................................... 37 Enclosure Attachment 1 Page 4 A AREVA Document No. 32-9222042-000 ASME Section Xl End of Life Analysis of PVNGS3 RV BMI Nozzle Repair (Non-Proprietary) List of Tables (continued) Page 6.5 Primary Stress Evaluation ......................................................................................................... 39 7 .0 C O N C LU S IO NS .......................................................................................................................... 4 1 8 .0 R E F E R E NC E S ............................................................................................................................ 42 APPENDIX A : UPHILL SIDE FLAW EVALUATIONS ................................................................... A-1 APPENDIX B: DOW NHILL SIDE FLAW EVALUATIONS .............................................................. B-1 Page 5 Enclosure Attachment 1 Page 5 A AREVA Document No. 32-9222042-000 ASME Section XI End of Life Analysis of PVNGS3 RV BMI Nozzle Repair (Non-Proprietary) List of Tables Page Table 1-1: Safety Factors for Flaw Acceptance ................................................................................
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