ML16320A037
| ML16320A037 | |
| Person / Time | |
|---|---|
| Site: | Byron  |
| Issue date: | 11/01/2016 |
| From: | Noronha S, Riordan T AREVA |
| To: | Office of Nuclear Reactor Regulation |
| Shared Package | |
| ML16320A031 | List: |
| References | |
| 32-924434-002 | |
| Download: ML16320A037 (112) | |
Text
ATTACHMENT 6 AREVA Document #32-9244434-002, "Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis" NON-PROPRIETARY
Controlled Document 0402-01-F01 (Rev. 019, 6/25/2015)
A CALCULATION
SUMMARY
SHEET (CSS)
AREVA Document No. 32 - 9244434 - 002 Safety Related: IZ!Yes D No Title B~ron and Braidwood RVCH Nozzle As-Left J-Groove Anal~sis- Non Pro~rieta!}'.
PURPOSE AND
SUMMARY
OF RESULTS:
PURPOSE:
Due to concerns that Control Rod Drive Mechanism (CRDM), core exit thermocouple (CETC), and reactor vessel level indication system (RVLIS) nozzle penetration degradation may have occurred in the Reactor Vessel Closure Heads (RVCHs) at Byron Station, Units 1 and 2, and Braidwood Station, Units 1 and 2, Exelon Generation Company, LLC (Owner) contracted AREVA to create a modification to repair these nozzles as a contingency. In the event that a repair is necessary, an ID temper bead weld repair procedure has been developed wherein the lower portion of the nozzle is removed by a boring procedure and the remaining portion is welded to the low alloy steel reactor vessel head above the original Alloy 82/182 J-groove attachment weld. Per Reference [1 ], fracture mechanics analysis must be performed to justify the worst-case flaw(s) remaining in the original nozzle-to-RVCH weld (as-left J-groove weld) at the worst-case location(s)
The purpose of this calculation is to perform a fracture mechanics analysis of the worst-case flaws in the as-left J-groove weld at the worst-case penetration location. This analysis considers the worst-case nozzle location and utilizes material properties which bound the properties of all four units.
This document is the Non-Proprietary document for 32-9236713-003.
Proprietary information is contained within bold square brackets"[]".
SUMMARY
OF RESULTS:
A fatigue crack growth and fracture mechanics evaluation of the worst-case flaws in the as-left J-groove weld and buttering at the worst-case penetration location has been 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.
Limitation: The minimum metal temperature for performing a Hydrostatic test at any time after an IDTB repair has been made is [ ]
The following table summarizes the total oaaes contained in this document.
I Section I Main Body I AnnendixA I Aooendix B I Aooendix C I Total I I Pages I 60 I 23 I 23 I 5 I 111 I If the computer software used herein is not the latest version per the EASI list, THE DOCUMENT CONTAINS AP 0402-01 requires that justification be provided.
ASSUMPTIONS THAT SHALL BE THE FOLLOWING COMPUTER CODES HAVE BEEN USED IN THIS DOCUMENT: VERIFIED PRIOR TO USE CODENERSION/REV CODENERSION/REV DYes ANSYS 14.5.7
- IX! No
- See Section 5.1 for justification.
Page 1 of 111
Controlled Document A 0402-01-F01 (Rev. 019, 6/25/2015)
AREVA Qocument No. 32-9244434.-002 Byron ~nd Btr;iiqwood RVCH Notzle As~Left J~Groi;ive Analysis- Non Pioprief"!ry Review Method; IZ! Design Review (Detailed Check)
D Alt~miate Calciulati_on Signatur~ Block P/roA N;:tnie and Title ;:tncJ Page.s/Secfi.ons (printed or typed) Signature LP/LR Date Prepared/Reviewed/Approved Silvester Noro.t'Jha p All Prinqipal E:ngi:neer ~~ I I\ t \I~
To:n;iRiott;lan R All Engineer IV ~ OltJOV2Df'
'/{/~
Tim Wiget .AH p~~
A Engineering Manager
,/
Notes: P/R/A designates Preparer (P), Reviewer (.R), Appro.ver (A);
LP/LR d~sigoates Lc:;ad Prepll!~r (Ll'), Lead R~view~r (L~)
In .reviewing an_d approvfug the initla1 reiease (Rev. 000), 'the lead review.er/approver shall desi~ate ~All' in p!\ges/sections rev!ewed/approved.
In reviewi11g. and appi'oving revisions, the lead prepar.er and lead reviewer shall use 'All' ih the pages/sections r<)vkwed/ijpproved. 'AIP means that the changes ap_d the effect of the cbauges on 1he entire document hav.e been reviewed/appro.veci. It does *not mean that the lead reviewer/approver has reviewed/approved ail the pages of the dooumertt.
Project Manager Approval of.Customer References (NIA if not applicable)
Name Title (pririteo or typ~tf} (printed or typed) Signature Date NIA Page2
Controlled Document A 0402-01-F01 (Rev. 019, 6/25/2015)
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Signature Block (Continued)
Mentoring Information (not required per 0402-01)
Name Title Mentor to:
(printed or typed) (printed or typed) (P/R) Signature Date NIA Page3
Controlled Document A 0402-01-F01 (Rev. 019, 6/25/2015)
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprieta,ry Record of Revision Revision Pages/Sections/Paragraphs No. Changed Brief Description I Change Authorization 000 All Initial Release This is a complete Revision.
001 All Non-Proprietary document for 32-9236713-002 002 Section 4.2.1 Redacted proprietary material designations.
Redacted proprietary material designation and material Section 4.2.2 property values in the tables.
Non-Proprietary document for 32-9236713-003.
Page4
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table of Contents Page SIGNATURE BLOCK ................................................................................................................................ 2 RECORD OF REVISION .......................................................................................................................... 4 LIST OF TABLES ..................................................................................................................................... 7 LIST OF FIGURES ................................................................................................................................... 9 1.0 PURPOSE ................................................................................................................................... 10 2.0 ANALYTICAL METHODOLOGY ................................................................................................. 12 2.1 Stress Intensity Factor Solution ...................................................................................................... 12 2.1.1 Plastic Zone Correction .................................................................................................... 13 2.2 Fatigue Crack Growth ..................................................................................................................... 18 2.3 Linear Elastic Fracture Mechanics .................................................................................................. 19 2.4 Elastic-Plastic Fracture Mechanics ................................................................................................. 19 2.4.1 Screening Criteria .................................................................................... :........................ 19 2.4.2 Flaw Stability and Crack Driving Force ............................................................................. 19 2.5 Primary Stress Analysis ..................................................................................................................21 2.6 Section XI Code Year Reconciliation .............................................................................................. 21 3.0 ASSUMPTIONS .......................................................................................................................... 22 3.1 Unverified Assumptions ...................................................................................................................22 3.2 Justified Assumptions ......................................................................................................................22 3.3 Modeling Simplifications ..................................................................................................................22 4.0 DESIGN INPUTS ........................................................................................................................ 23 4.1 Geometry .........................................................................................................................................23 4.2 Materials ..........................................................................................................................................24 4.2.1 Material Specifications ......................................................................................................24 4.2.2 Mechanical Material Properties ........................................................................................24 4.2.3 Fracture Material Properties .............................................................................................26 4.3 Transients ........................................................................................................................................30 4.4 Finite Element Model .......................................................................................................................32 4.4.1 Boundary Conditions ........................................................................................................32 4.4.2 Applied Stresses ...............................................................................................................32 5.0 COMPUTER FILES ..................................................................................................................... 35 5.1 Software ..........................................................................................................................................35 5.2 Computer Files ................................................................................................................................35 Page 5
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table of Contents (continued)
Page 6.0 CALCULATIONS ......................................................................................................................... 40 6.1 Stress Intensity Factors ..........................................................................................................,....... .40 6.2 Fatigue Crack Growth .....................................................................................................................40 6.3 LEFM Evaluation .............................................................................................................................41 6.4 EPFM Evaluations ...........................................................................................................................44 6.5 Primary Stress Evaluation ...............................................................................................................47 6.5.1 Limit Load Finite Element Model ..................................................................................... .47 6.5.2 Calculation of Flaw Area Removed .................................................................................. 53
7.0 CONCLUSION
S .......................................................................................................................... 58
8.0 REFERENCES
............................................................................................................................ 59 APPENDIX A: UPHILL SIDE FLAW EVALUATIONS ......................................................................... A-1 APPENDIX B: DOWNHILL SIDE FLAW EVALUATIONS .................................................................. B-1 APPENDIX C: EVALUATION OF THE [ ] TRANSIENT ........... C-1 Page6
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary List of Tables Page Table 1-1: Safety Factors for Flaw Acceptance ..................................................................................... 11 Table 4-1: Key Dimensions .................................................................................................................... 23 Table 4-2: Component Materials ............................................................................................................ 24 Table 4-3: RVCH Material Properties .................................................................................................... 24 Table 4-4: J-Groove Weld, and Butter Material Properties .................................................................... 25 Table 4-5: Cladding Material Properties ................................................................................................ 25 Table 4-6: Fracture Material Properties .................................................................................................26 Table 4-7: CVN Test Data ......................................................................................................................27 Table 4-8: Transients ............................................................................................................................. 30 Table 4-9: Emergency and Faulted Transients ...................................................................................... 31 Table 4-10: Stress Result Files .............................................................................................................. 33 Table 5-1: Computer Files ..................................................................................................................... 35 Table 5-2: Computer Files for Rev 002 .................................................................................................. 39 Table 6-1: Uphill Position 17 LEFM Results .......................................................................................... 42 Table 6-2: Downhill Position 17 LEFM Results ..................................................................................... .43 Table 6-3: Uphill Position 17 EPFM Results ......................................................................................... .45 Table 6-4: Downhill Position 17 EPFM Results .................................................................................... .46 Table 6-5: Model Areas Removed by the Cutouts to Represent Postulated Flaws ............................... 55 Table 6-6: Flaw Area Comparison ......................................................................................................... 57 Table A-1: SIFs for Uphill Side -Welding Residual Stress ........................................ ;........................ A-1 Table A-2: SIFs for Uphill Side - Design Condition ............................................................................. A-2 Table A-3: SIFs for Uphill Side - [ ] ........................................................ A-3 Table A-4: SI Fs for Uphill Side - [ ] ....................................................... A-4 Table A-5: SIFs for Uphill Side - [ ] ............................................................. A-5 Table A-6: SIFs for Uphill Side - [ ]................................................................... A-6 Table A-7: Fatigue Crack Growth for [ ] (Uphill) ............................................ A-7 Table A-8: Fatigue Crack Growth for [ ] (Uphill) .................................. A-8 Table A-9: Fatigue Crack Growth for [ ] (Uphill) .................................. A-9 Table A-1 O: Fatigue Crack Growth for [ ] (Uphill) .............................................. A-10 Table A-11: Fatigue Crack Growth [ ] (Uphill) ................................. A-11 Table A-12: Fatigue Crack Growth for [ ] (Uphill) ..................................................... A-12 Table A-13: Fatigue Crack Growth for [ ] (Uphill) ....................................................... A-13 Table A-14: Fatigue Crack Growth for [ ] (Uphill) ........................................................ A-14 Table A-15: Fatigue Crack Growth for [ ] (Uphill) ............................................... A-15 Table A-16: Fatigue Crack Growth for [ ] (Uphill) ............................. A-16 Table A-17: Fatigue Crack Growth for [ ] (Uphill) ................... A-17 Page 7
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary List of Tables (continued)
Page Table A-18: Fatigue Crack Growth for [ ] (Uphill) ................................................ A-18 Table A-19: Fatigue Crack Growth for [ ] (Uphill) ................................ A-19 Table A-20: Fatigue Crack Growth for [ ] (Uphill) ................................................. A-20 Table A-21: Fatigue Crack Growth for [ ] (Uphill) ............................................................ A-21
- Table A-22: EPFM Evaluation for [ ] (Uphill) ............................................................ A-22 Table 8-1: SIFs for Downhill Side - Welding Residual Stress ............................................................. 8-1 Table 8-2: SIFs for Downhill Side - Design Condition ......................................................................... 8-2 Table 8-3: SIFs for Downhill Side - [ ] ................................................... 8-3 Table 8-4: SIFs for Downhill Side - [ ] .................................................. 8-4 Table 8-5: SIFs for Downhill Side - [ ] ........................................................ 8-5 Table 8-6: SIFs for Downhill Side - [ ] .............................................................. 8-6 Table 8-7: Fatigue Crack Growth for [ ] (Downhill) ........................................ 8-7 Table 8-8: Fatigue Crack Growth for [ ] (Downhill) ............................. 8-8 Table 8-9: Fatigue Crack Growth for [ ] (Downhill) .............................. 8-9 Table 8-10: Fatigue Crack Growth for [ ] (Downhill) ......................................... 8-10 Table 8-11: Fatigue Crack Growth for [ ] (Downhill) ............................ 8-11 Table 8-12: Fatigue Crack Growth for [ ] (Downhill) ................................................ 8-12 Table 8-13: Fatigue Crack Growth for [ ] (Downhill) ................................................... 8-13 Table 8-14: Fatigue Crack Growth for [ ] (Downhill) ................................................... 8-14 Table 8-15: Fatigue Crack Growth for [ ] (Downhill) ............................................ 8-15 Table 8-16: Fatigue Crack Growth for [ ] (Downhill) ......................... 8-16 .,I Table 8-17: Fatigue Crack Growth for [ ] (Downhill) .............. 8-17 Table 8-18: Fatigue Crack Growth for [ ] (Downhill) ........................................... 8-18 I Table 8-19: Fatigue Crack Growth for [ ] (Downhill) ............................ 8-19 Table 8-20: Fatigue Crack Growth for [ ] (Downhill) ............................................. 8-20 Table 8-21: Fatigue Crack Growth for [ ] (Downhill) ....................................................... 8-21 Table 8-22: EPFM Evaluation for [ ] (Downhill) ..................................................*...... 8-22 Table C-1: SIFs for Uphill Side - [ ] ............................................................................................. C-1 Table C-2: SIFs for Downhill Side - [ ] ......................................................................................... C-2 Table C-3: Uphill Position 17 [ ] LEFM Results .......................................................................... C-3 Table C-4: Downhill Position 17 [ ] LEFM Results ..................................................................... C-3 Table C-5: Uphill Position 17 [ EPFM Results .......................................................................... C-4 Table C-6: Downhill Position 17 [ ] EPFM Results ..................................................................... C-5 Page 8
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary List of Figures Page Figure 2-1: Finite Element Model Isometric View .................................................................................. 14 Figure 2-2: Uphill Crack Fronts .............................................................................................................. 15 Figure 2-3: Downhill Crack Fronts ......................................................................................................... 16 Figure 2-4: Initial Flaw Sizes .................................................................................................................. 17 Figure 4-1: J-R Curves as a Function of Temperature .......................................................................... 29 Figure 4-2: Weld Residual Stress Mapped to Down hill Crack Front 1 ................................................... 34 Figure 6-1: Limit Load Model Penetration Layout ................................................................................. .48 Figure 6-2: Limit Load Model Geometry ............................................................................................... .49 Figure 6-3: Limit Load Model Finite Element Mesh ............................................................................... 50 Figure 6-4: Equivalent Stresses at the Limit Pressure ........................................................................... 51 Figure 6-5: Finite Element Mesh for Limit Load Test Case .................................................................... 52 Figure 6-6: Limit Load Test Case Equivalent Stress at Limit Pressure .................................................. 53 Figure 6-7: Area Calculation Diagram ............................................................................. ,...................... 54 Figure 6-8: Outermost Penetration Crack Face Areas ........................................................................... 56 Figure 6-9: Crack Growth Area Calculation ........................................................................................... 57 Figure A-1: J-T Diagram for [ ] (Uphill) .................................................................... A-23 Figure B-1: J-T Diagram for [ ] (Downhill) .........................................................*...... B-23 Page 9
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 1.0 PURPOSE Due to concerns that Control Rod Drive Mechanism (CRDM), core exit thermocouple (CETC), and reactor vessel level indication system (RVLIS) nozzle penetration degradation may have occurred in the RVCHs at Byron Station, Units 1 and 2, and Braidwood Station, Units 1 and 2, Exelon Generation Company, LLC (Owner) contracted AREVA to create a modification to repair these nozzles as a contingency. In the event that a repair is necessary, an ID temper bead weld repair procedure has been developed wherein the lower portion of the nozzle is removed by a boring procedure and the remaining portion is welded to the low alloy steel reactor vessel head above the original Alloy 82/182 J-groove attachment weld. Per Reference [1], fracture mechanics analysis must be performed to justify the worst-case flaw(s) remaining in the original nozzle-to-RVCH weld (as-left J-groove weld) at the worst-case location(s). Since a potential flaw in the J-groove weld cannot be sized by currently available non-destructive examination techniques, it is considered that the worst-case as-left condition of the remaining J-groove weld includes degraded or cracked weld material extending through the entire J-groove weld and Alloy 82/182 butter material (due to PWSCC). It is further postulated that this flaw could propagate into the low alloy steel head by fatigue.
The purpose of this calculation is to perform a fracture mechanics analysis of the worst-case flaws in the as-left J-groove weld at the worst-case penetration location. This analysis considers the worst-case nozzle location and utilizes material properties which bound the properties of all four units.
Per Reference [1] the applicable code is ASME Section XI, 2001 Edition with Addenda through 2003 (Reference
[2]) for Braidwood Units 1 and 2, and 2007 Edition with Addenda through 2008 for Byron Units 1 and 2 (Reference [28)). Analysis in this document utilizes Reference [2], which is more restrictive than Reference [28)
(see Section 2.6). If the service life of the component is shown to be limited, an alternate approach of using ASME Section XI Code Case N-749 (Reference [3]) as modified by the Nuclear Regulatory Commission (see attachment to Reference [4]), which is more conservative than the most recent equation proposed by NRC in Reference [29), will be considered in the evaluation. 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.
The purpose of revision 002 is to address the [ ] (Appendix C).
Page 10
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table 1-1: Safety Factors for Flaw Acceptance LEFM*
Operating Condition Evaluation Method Fracture Toughness I K1 Normal/Upset K1a fracture toughness Y10=3.16 Emergency/Faulted K1c fracture toughness Y2 = 1.41 EPFM Based on Limited Ductile Flaw Extension**
Operating Condition Evaluation Method Primary Secondary Normal/Upset Jo. 1 limited flaw extension 2.0 1.0 Emergency/Faulted Jo. 1 limited flaw extension 1.5 1.0 EPFM Based on Limited Ductile Flaw Extension and Stability***
Operating Condition Evaluation Method Primary Secondary Normal/Upset J/T based flaw stability 2.14 1.0 Normal/Upset Jo. 1 limited flaw extension 1.5 1.0 Emergency/Faulted J/T based flaw stability 1.2 1.0 Emergency/Faulted Jo. 1 limited flaw extension 1.25 1.0
- LEFM safety factors are from IWB-3612 of ASME Section XI (Reference [2]).
- EPFM safety factors based on Section 3.1 of Code Case N-749 (Reference [3]).
- EPFM safety factors based on Section 3.2 of Code Case N-749 (Reference [3]).
Page 11
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 2.0 ANALYTICAL METHODOLOGY The basic analytical methodology is outlined below. Details are provided in the following subsections.
- 1. Postulate radial-axial flaws in the J-groove weld and butter of the worst case nozzle location. Past experience has shown that the nozzle with the largest hillside angle is the worst case location, which for the current configuration is the CETC nozzle. The radial-axial flaws are postulated since the hoop stresses are dominant.
- 2. Develop explicit three dimensional finite element crack models of the postulated flaws on the uphill and downhill side in order to calculate the stress intensity factors (SIFs). In order to determine SIFs at varying flaw sizes two uphill crack models and two downhill crack models will be generated with increasing flaw sizes.
- 3. Develop a mapping procedure to transfer stresses from an uncracked finite element stress model to the crack face of each crack model, enabling stress intensity factors to be calculated for arbitrary stress distributions over the crack face utilizing the principle of superposition. This strategy makes it possible to obtain pressure and thermal stresses from independent thermal/structural analyses and transfer these stresses to the crack model to support flaw evaluation. Mapping is used for the present assignment to apply residual stresses from weld residual stress analysis and operating stresses from Section III fatigue analysis to the three-dimensional crack models discussed above.
- 4. Obtain stress intensity factors for each loading condition at varying positions along the crack front by using the ANSYS KCALC command.
- 5. Calculate fatigue crack growth for cyclic loading conditions using operational stresses from pressure and thermal loads and crack growth rates from Article A-4300 of Section XI for ferritic material in a primary water environment. Residual stresses are included in the fatigue crack growth calculations as a mean stress, which affects the fatigue crack growth rates through the R ratio (Kmu/Kmax).
- 6. Utilize the screening criteria of ASME Code Case N-749 (Reference [3]) as modified by the NRC (Reference [4]) to determine the appropriate method of analysis (LEFM or EPFM). For LEFM flaw evaluations, compare the stress intensity factors to the available fracture toughness, with appropriate safety factors. When the material is more ductile and EPFM is the appropriate analysis method, evaluate in accordance with ASME Code Case N-749 (Reference [3]). A limit load analysis is performed to demonstrate that Items 3.l(c) or 3.2(a)(3) of Reference [3] are satisfied. Items 3.l(c) or 3.2(a)(3) requires that the primary stress limit ofNB-3000 are satisfied, considering a local reduction of the pressure boundary area equal to the area of the flawed material.
2.1 Stress Intensity Factor Solution The SIF solutions for the postulated flaws evaluated by :fracture mechanics analysis are calculated using three-dimensional finite element models with crack tip elements. The model includes the Reactor Vessel Closure Head (RVCH) with existing J-groove weld. The nozzle and IDTB weld are conservatively not included since these materials would provide additional constraint, limiting the crack opening. An isometric view of the overall finite element model developed for this analysis is shown in Figure 2-1.
Radial-axial flaws are postulated and analyzed separately on the uphill and downhill sides of the nozzle and shown in Figure 2-2 and Figure 2-3. For each postulated flaw two finite element models are generated with a flaw size increment of 0.625" in order to capture the variation of SIF with flaw size. For each postulated flaw, SIFs are calculated at a total of 17 positions along the crack front starting with position 1 at the RVCH ID and going to position 17 at the nozzle bore as shown in Figure 2-2 and Figure 2-3. Stress intensity factors are Page 12
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary calculated using the ANSYS KCALC command (Reference [23]), which determines the stress intensity factors based on displacements in the vicinity of the crack tip. For "non-classical" flaw shapes with stress intensity factor calculated by the fmite element method it is both difficult and unnecessary to prescribe an initial flaw size. In order to track the flaw size during fatigue crack growth any characteristic dimension may be used as the initial flaw size. For this calculation the initial flaw size, ao, is chosen to be the vertical distance along the penetration bore in the fmite element model from the inside surface of the cladding to the butter/head interface (see Figure 2-4).
Stress intensity factors at flaw sizes between the modeled flaw sizes are linearly interpolated. If the flaw size is larger than the largest flaw in the finite element model, the stress intensity factor is determined using the following scaling rule where K1(a1) is a known SIF at flaw size a1 and K1(a2) is the desired SIF at flaw size a2 . This approach follows from the fundamental expression for the stress intensity factor, K1 = CJ....fi[a, where for a giv'en applied stress and geometry the stress intensity factor scales with the square root of flaw size.
2.1.1 Plastic Zone Correction The Irwin plastic zone correction is used to account for a moderate amount of yielding. For plane strain conditions the correction is (Reference [5], Eq. 2.63)
= ~(K1 (a))
2 r.
Y 67r Cly where Kr( a) is the stress intensity factor at the actual crack size (a), and cry is the material's yield strength. The effective crack size, ae, is calculated as ae =a+ ry The stress intensity factor at the effective flaw size is then calculated using the scaling law derived above as Page 13
Controlled Document A
AREVA Document No . 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary AN SYS Rl 4.5 Crack Medel = uhl Figure 2-1: Finite Element Model Isometric View Page 14
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 2-2: Uphill Crack Fronts, Page 15
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 2-3: Downhill Crack Fronts Page 16
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 2-4: Initial Flaw Sizes Page 17
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 2.2 Fatigue Crack Growth Fatigue crack growth is calculated using the fatigue crack growth rate model from Article A-4300 of Reference
[2] as da _ ( )n dN - Co !J.K1 where tJ.K1 is the stress intensity factor range in ksi.Yin, and da/dN is the crack growth rate in inches/cycle. The crack growth rates for a surface flaw will be utilized since the postulated flaw(s) would result in the low alloy steel head being exposed to the primary water environment.
The detailed equations for calculating the fatigue crack growth rate are presented below.
!J.K1 = KMax - KMin R = KMinfKMax 0:::::; R:::::; 0.25, !J.K1 < 17.74 n = 5.95 5 = 1.0 Co = 1.02 x 10- 12 5 n = 1.95 5=1.0 C0 = 1.01 x 10- 7 5 0.25:::::; R:::::; 0.65, !J.K1 < 17.74[(3.75R + 0.06)/(26.9R - 5.725)] 0 *25 n = 5.95 5 = 26.9R - 5.725 C0 = 1.02 x 10- 12 5
!J.K1 ~ 17.74[(3.75R + 0.06)/(26.9R - 5.725)] 0 *25 n = 1.95 5 = 3.75R + 0.06 C0 = 1.01 x 10- 7 5 0.65 :::::; R :::::; 1.00, !J.K1 < 12.04 n = 5.95 5 = 11.76 Co= 1.02 x 10- 12 5 n = 1.95 5 = 2.5 C0 = 1.01x10-7 5 Page 18 I
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 2.3 Linear Elastic Fracture Mechanics After fatigue crack growth is calculated the flaw is evaluated using Linear Elastic Fracture Mechanics (LEFM).
Article IWB-3 612 of Section XI (Reference [2]) requires that the applied stress intensity factor be less than the available fracture toughness at the crack tip temperature, with appropriate safety factor, as outlined below.
Normal/Upset Conditions: K1 < K1a/..ff0 Emergency/Faulted Conditions: K1 < K1c/.J2.
In the above K1a is the fracture toughness based on crack arrest and K1c is the fracture toughness based on crack initiation. In the evaluation of the above limits, a plastic zone correction is incorporated using the methodology described in Section 2.1.1.
2.4 Elastic-Plastic Fracture Mechanics Elastic-plastic fracture mechanics (EPFM) will be used as an alternative acceptance criteria when the flaw related failure mechanism is unstable ductile tearing. LEFM would be used to assess the potential for non-ductile failure, while limit analysis would be used to check for plastic collapse.
2.4.1 Screening Criteria ASME Code Case N-749 states that EPFM acceptance criteria are applicable to ferritic steel components on the upper shelf of the Charpy energy curve when the metal temperature exceeds the upper shelf transition temperature, Tc. The NRC has proposed a modification to the Code Case definition of Tc, which is given below (see Reference [4 ]).
Tc= 170.4°F + 0.814 X RTNDT When the metal temperature exceeds Tc, EPFM analysis is applicable, otherwise LEFM analysis is applicable.
It is noted that more recently, the NRC has proposed a slightly different equation for Tc in Reference [29]. This more recently proposed equation is less restrictive (i.e., allows EPFM at lower temperature), and thus the equation above used in this analysis is conservative.
2.4.2 Flaw Stability and Crack Driving Force Elastic-plastic fracture mechanics analysis will be performed based on ASME Code Case N-749 (Reference [3])
to evaluate crack driving force and flaw stability (if applicable). Two possible sets of acceptance criteria for EPFM are defined in Code Case N-749:
- Section 3 .1 Acceptance Criteria Based Solely on Limited Ductile Crack Extension, or
- Section 3.2 Acceptance Criteria Based on Limited Ductile Crack Extension and Stability.
Section 3.1 states that the flaw is acceptable if the crack driving force, as measured by the applied I-integral (Japp) with appropriate safety factors applied to the loads, is less than the than the I-integral of the material Cimat) at a ductile crack extension of 0.1 inch (J0.1). If the criteria of Section 3.1 are not met, the flaw may still be acceptable if the criteria of Section 3 .2 are met. Section 3 .2 allows lower safety factors for the crack driving force check, and additionally requires that flaw stability be evaluated with appropriate safety factors. The flaw stability analysis will be performed using a I-integral/tearing modulus (J-T) diagram to evaluate flaw stability under ductile tearing, where J is either the applied (Japp) or the material Cimat) I-integral, and T is the tearing modulus, defined as (Ela/)
(oJ/oa). Flaw stability and crack driving force assessments will utilize the safety factors from Code Case N-749 as outlined in Table 1-1.
The general methodology for performing an EPFM analyses is outlined below.
Page 19
Controlled Docun1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Let E'== E/(1-112)
Final flaw depth == a Total applied Kt== Ktapp Kr due to pressure (primary) == Ktp Kr due to residual plus thermal (secondary)== Kts = Ktapp - Ktp Safety factor on primary loads == SFp Safety factor on secondary loads == SFs Total applied Kr with safety factors, Kt'== SFp *Ktp + SFs *Kts For small scale yielding at the crack tip, a plastic zone correction (see Section 2.1.1) is used to calculate an effective flaw depth based on ae =a+- 1(K*)_I 6n CJy 2
which is used to update the total applied stress intensity factor based on Kf =Kt~
The applied I-integral is then calculated using the relationship (K')2 1
fapp = /E' The applied I-integral is checked against Io.i, demonstrating that the crack driving force falls below the I-R curve at a crack extension of 0.1 inch.
For flaw stability analysis, the final parameter needed to construct the I-T diagram is the tearing modulus. The applied tearing modulus, Tapp, is calculated by numerical differentiation for small increments of crack size (da) about the crack size (a), according to
= !_ (fapp(a + da) - fapp(a - da))
Tapp cr 2 2 da f
The material I-T curve is determined as described in Section 4.2. Constructing the I-T diagram as shown below, Page 20
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary J
T flaw stability is demonstrated at an applied I-integral when the applied tearing modulus is less than the material tearing modulus. Alternately, the applied I-integral is less than the I-integral at the point of instability.
2.5 Primary Stress Analysis Items 3. l(c) and 3.2(a)(3) of Reference [3] state that the flawed component must meet the primary stress limits of NB-3000, assuming a local area reduction of the pressure retaining membrane that is equal to the area of the flaw.
To evaluate the requirement, article NB-3228.1 of Section III of the ASME Code [24] is utilized. NB-3228.1 states that the limits on General Membrane Stress Intensity (NB-3221.1 ), Local Membrane Stress Intensity (NB-3221.2), and Primary Membrane Plus Primary Bending Stress Intensity (NB-3221.3) need not be satisfied at a specific location if it can be shown by limit analysis that the specified loadings do not exceed two-thirds of the lower bound collapse load. The yield strength to be used in these calculations is 1.5Sm. Per NB-3112.l(a) the Design Pressure shall be used in showing compliance with this limit.
2.6 Section XI Code Year Reconciliation The only applicable change in Section XI between the 2001 Edition with Addenda through 2003 (Reference [2])
and the 2007 Edition with Addenda through 2008 (Reference [28]) is in the IWB-3612(a) acceptance criteria for normal and upset conditions. IWB-3612(a) of Reference [28] allows the use of the Krc measure of fracture toughness, while IWB-3612(a) of Reference [2] uses the more restrictive Kra and is conservatively bounding.
Therefore, use of Reference [2] throughout this analysis is acceptable.
Page 21
Controlled Docun1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 3.0 ASSUMPTIONS 3.1 Unverified Assumptions No unverified assumptions are used in this calculation.
3.2 Justified Assumptions The following justified assumptions are used in this calculation:
- 1. For fatigue crack growth calculations cycles are assumed to accumulate at a linear rate, i.e., in each year the number of cycles utilized is the total number of design cycles divided by the plant design life. This assumption is reasonable since experience shows that linear rates generally envelope the accumulation rates observed for transients based on plant operating experience (see Reference [6], TODI-BYR-15-008 cycle counts).
- 2. A 20 year license extension for each unit is assumed. Based on this and review of current license expiration dates for each unit fatigue crack growth for 33 years is considered.
- 3. For the limit load analysis (Section 6.5.1), an eighth symmetric model is utilized. The actual symmetry of the CRDM nozzle layout is quarter rotational symmetry. The eighth of the head modeled results in one additional CRDM penetration in each quadrant, which conservatively removes more material (i.e., there is less metal available to carry the applied loadings) and has negligible effect on the applicability of the symmetry boundary condition due to the size of the penetration compared to the size of the head.
3.3 Modeling Simplifications The following modeling simplifications are used in this calculation:
- 1. The geometry of the J-groove weld and butter is simplified to allow for a higli quality mesh in this area and insertion of the crack tip elements needed to calculate stress intensity factors. Simplifications include the "kink" in the crack fronts rather than a smooth radius and neglecting the small fillet weld. These simplifications are typical of these types of analysis and do not impact the results.
- 2. For the limit load analysis (Section 6.5 .1 ), the material removed to represent the J-groove weld, butter and crack growth has a simplified geometry to facilitate modeling. This simplification has no impact since acceptable area is removed.
Page 22
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 4.0 DESIGN INPUTS 4.1 Geometry The existing geometry of the RVCH and J-groove weld(s) for each unit are show in References [7], [8], [9], [10],
[11], [12], [13], and [14]. The proposed repair configuration is provided in References [15] and [16]. Key dimensions are listed in Table 4-1.
Table 4-1: Key Dimensions Description Value Reference/Comments Head Inside Radius to Cladding [ ] [16]
Head Thickness [ ] [16]
Cladding Thickness [ ] [16]
Bore Diameter [ ] [16]
Horizontal Radius to Outermost Penetration [ ] [16]
Page 23
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 4.2 Materials 4.2.1 Material Specifications The material designations of each component are listed in Table 4-2.
Table 4-2: Component Materials Component Material Reference/Comments RVCH Reference [ 1]
[ l Cladding Reference [6], Equip.
[ l Spec 676413 Reference [ 1]
Existing J-Groove Weld/Buttering
[ l 4.2.2 Mechanical Material Properties The material properties are taken from the original construction code, Reference [17]. The material properties for each component are provided in Table 4-3, Table 4-4, and Table 4-5. The [ ] properties are also used for the [ ] weld filler metals.
Table 4-3: RVCH Material Properties
[ ]
Temperature (°F) I a (1/°F) I E (psi) I v (-) I Ov (ksi) I Ou (ksi)
I Reference [17] Location I Table 1-5.0, Coeff. B I Table 1-6.0 I Typical I Table 1-2.1 I Table 1-1.1 I Page 24
Controlled Document A.
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table 4-4: J-Groove Weld, and Butter Material Properties Temperature {°F) a {1/°F) E (psi) v {-) Oy (ksi) Ou (ksi)
I Reference [17] Location I Table 1-5.0, Coeff. B I Table 1-6.0 I Typical I Table 1-2.2 I Table 1-1.2 I Table 4-5: Cladding Material Properties
[ ]
Temperature {°F) a (1/°F) E {psi) v {-)
I Reference [17] Location J I Table 1-5.0, Coeff. B Table 1-6.0 I Typical I Page 25
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 4.2.3 Fractur~ Material Properties Table 4-6 provides the reference temperature for nil-ductility (RTNnT), and the sulfur content for the closure head center disc for each of the four units (Reference [18]). The analysis performed in this calculation uses the bounding values of all units, which is an RTNnT of [ ]
Table 4-6: Fracture Material Properties Plant Unit Heat No. RT NOT (°F) Sulfur (wt%)
Byron 1 C3486-1 [ 1 [ 1 Byron 2 C4375-2 [ 1 [ 1 Braidwood 1 D1398-l [ 1 [ 1 Braidwood 2 B9754-1 [ 1 [ 1 Reference [18] provides .an estimate of the Charpy V-notch upper-shelf energy (USE) which is based on the average energy from CVN tests at RTNDT+60°F. Review of the Charpy data provided in the CMTRs attached to Reference [18] indicates that this is a very conservative estimate of USE, as the percent shear fractures range from 50%-60% at this level. Per Reference [20], USE is defined by ASTM El85 (Reference [19]), which provides the following definition of the USE:
Charpy upper-shelf energy level-the average energy value for all Charpy specimen tests (preferably three or more) whose test temperature is at or above the Charpy upper-shelf onset; specimens tested at temperatures greater than 83°C (150°F) above the Charpy upper-shelf onset shall not be included, unless no data are available between the onset temperature and onset +83 °C (+ 150°F).
Charpy upper-shelf onset-the test temperature above which the fracture appearance of all Charpy specimens tested is at or above 95% shear.
The CVN test data from the CMTRs is provided in Table 4-7. From Table 4-7, a lower bound USE of
[ ] is selected based on the Braidwood 1 data at [ ] where the percent shear fracture is
[ ] Note that the use of data at [ ] shear fracture is still conservative relative to the ASTM definition of 95% shear fracture.
Page 26
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table 4-7: CVN Test Data Energy (ft-lbs) Percent Shear Fracture Plant Temperature ("F)
Test 1 I Test 2 I Test 3 I Average Test 1 I Test 2 I Test 3 Byron 1 212 Byron 1 100 Byron 1 70 Byron 1 so Byron 1 40 Byron 1 10 Byron 1 -150 Byron 2 212 Byron 2 100 Byron 2 80 Byron 2 60 Byron 2 20 Byron 2 -50 Byron 2 -100 Braidwood 1 212 Braidwood 1 60
~
Braidwood 1 30 Braidwood 1 0 Braidwood 1 -30 Braidwood 1 -60 Braidwood 1 -100 Braidwood 2 212 Braidwood 2 70 Braidwood 2 60 Braidwood 2 0 Braidwood 2 -10 Braidwood 2 -20 Braidwood 2 -60 Page 27
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary From Article A-4200 of Reference [2], the lower bound fracture toughness for crack arrest, Kra, is calculated as K1a = 26.8 + 12.445exp[0.014S(T - RTNDT)]
where Tis the crack tip temperature, Kra is in units ofksi.Yin, and T and RTNDT are in units of °F. In the present calculations, Kra is limited to a maximum value of 200 ksi.Yin (upper-shelf fracture toughness). The crack arrest K1a upper shelf toughness of 200 ksi.Yin is achieved at T-RTNDT > 182 °F.
A higher measure of fracture toughness is provided by the K 1c fracture toughness for crack initiation, approximated in Article A-4200 of Section XI (Reference [2]) by K1c = 33.2 + 20.734exp[0.02(T - RTNDr)]
The crack initiation Krc upper shelf toughness of200 ksi.Yin is achieved at T-RTNDT > 105 °F.
The I-integral resistance (J-R) curve, needed for the EPFM method of analysis, is obtained from the following correlation for reactor pressure vessel plate with less than 0.018 weight percent sulfur (Reference [20], Section 3.3.1) lmat = MF{C1(Ll.a)Cz exp(C3(.1.a)C4)}
where MF is a margin factor, and ~a is the crack extension. C; are constants which depend on the crack tip temperature and the Charpy V-notch upper-shelf energy as defined below C1 = exp(-2.44 + 1.13 ln(CVN) - 0.00277T)
C2 = 0.077 + 0.116 ln C1 C3 = -0.0812 - 0.0092 ln C1 C4 = -0.409 where CVN is the Charpy V-notch upper-shelf energy in ft-lbs, and Tis the crack tip temperature in °F. In this analysis the margin factor, MF, is taken as 0.749 for all cases including faulted where it may be taken as one. The resulting material J-R curve is plotted for several temperatures in Figure 4-1.
Page 28
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 4-1: J-R Curves as a Function of Temperature The material tearing modulus is calculated using the following equation Tmat = (~) a~:at where Eis the Elastic Modulus, crr is the flow stress defined as 0.5(cry + cru), and the derivative of the J-R curve is a;at = MF{C1C2(b.a)C2-1 + C1C3C4(b.a)C2+Crl}exp(C3(b.a)C4)
Page 29
Controlled Docu1Tient A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 4.3 Transients Fatigue crack growth will be calculated for the Normal and Upset transients listed in Table 4-8, based on Table 4-6 of the Section III analysis (Reference [22]). Per Reference [6] (TODI-BYR-15-008) the design cycles specified are applicable for a [ ] life.
Table 4-8: Transients I Transient I Abbreviation Service Level I Cycles I CyclesNear I Normal Normal Normal Normal Normal Upset Upset Upset Upset Upset Upset Upset Upset Upset Test
- The ( ] transient is addressed in Appendix C.
Test Additionally, the Emergency and Faulted transient pressure temperature curves provided in Reference [6] (TODI BYR-15-009 & TODI BYR-15-012) were reviewed and the critical transients were selected for analysis based on the discussion below in Table 4-9. Emergency and Faulted transients have a small number of cycles (5 or less) and are therefore not considered for fatigue.
Page 30
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table 4-9: Emergency and Faulted Transients Page 31
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 4.4 Finite Element Model The finite element model utilized is a three-dimensional half symmetry model. The model is meshed using ANSYS element types SOLIDl86 and SOLID187. The crack tip elements are SOLID186 elements collapsed into wedges with the appropriate mid-side nodes moved to the quarter points to simulate the singularity at the crack tip. A base geometry and mesh are generated in the input file "base_model.inp", and the explicit crack models are then created by replacing the appropriate brick elements with crack tip elements using the files "gen_crack_models.inp" and "CrackFanMesh2.mac".
4.4.1 Boundary Conditions The displacements are constrained normal to the face of the symmetry plane and the additional model cutting planes. The displacements of the nodes on the crack face are not constrained.
4.4.2 Applied Stresses Applied stresses are due to residual stresses and operating stresses. Residual stresses are obtained from the 3-D weld residual stress calculation documented in Reference [21]. Stresses are mapped to the crack face from the residual stress model to the crack finite element model through arrays of nodal locations and hoop stresses documented in Appendix B of Reference [21]. Figure 4-2 shows an example of the weld residual stresses mapped onto downhill crack face 1 side by side with contour plot of the stress from Reference [21]. Operating stresses are taken from the corresponding ASME Section III calculation (Reference [22]) and mapped to the crack face using the same methodology as the residual stresses. The operating pressure is also applied to the crack face to account for the additional loading.
The files used for stress results from References [21] and [22] are listed in Table 4-10.
Page 32
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table 4-10: Stress Result Files Load Stress File Page 33
Controlled Docu1'Tient A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 4-2: Weld Residual Stress Mapped to Downhill Crack Front 1 Page 34
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 5.0 COMPUTER FILES 5.1 Software ANSYS Version 14.5.7 (Reference [23]) was used in this analysis. Error notices were reviewed and none are applicable to the features utilized in this analysis, therefore, the use of this version is acceptable. All modeling and analyses were performed on the following computer:
- DELL Precision M6600, Intel(R) Core(TM) i7-2640M CPU @2.80GHz, 8GB of RAM
- Operating System: Windows 7, Service Pack 1, 64 Bit
- Name of person running tests: Tom Riordan
- Date of Tests Before Runs: February 23, 2015
- Date of Tests After Runs: May 1, 2015
- Date of Test for Rev 002 Runs: August 24, 2016 (verification test performed at same time as runs).
The test problem vml43 was run before and after the analysis and the results were found to be acceptable as documented in output files "vml43.out" and "vml43.vrt" (see Table 5-1). The test problem vml43 was also run for revision 002 and is documented in output files "vml43.out" and "vml43.vrt" (see Table 5-2).
5.2 Computer Files The computer files for runs performed in revision 000 are listed in Table 5-1. The files for revision 002 are listed in Table 5-2. Files are stored in ColdStor at the following paths:
\cold\General-Access\32\32-9000000\32-9236713-000\official (Table 5-1)
\cold\General-Access\32\32-9000000\32-9236713-002\official (Table 5-2)
Table 5-1: Computer Files CRC Checksum File Size (bytes) Modified Date Time File Name
./Kl:
21263 1578 Mar 9 2015 20:49:48 Design_dhl.KI 60449 1578 Mar 9 2015 22:18:41 Design_dh2.KI 43257 1578 Mar 9 2015 17:40:33 Design_uhl.KI 07900 1578 Mar 9 2015 19:10:35 Design_uh2.KI 21104 3300 Feb 10 2015 12:36:22 Get_SIF.mac 03319 3386 Feb 23 2015 19:08:04 SIF_Driver.mac 14846 326 Feb 23 2015 10:06:44 SIF_calc.inp 03910 82149439 Mar 10 2015 0:04:51 SIF_ca le.out 43416 6838 Mar 9 2015 20:52:58 Tr_CD_st_dhl.KI 31139 6838 Mar 9 2015 22:22:30 Tr_CD_st_dh2.KI 24024 6838 Mar 9 2015 17:43:46 Tr_CD_st_uhl.KI 33054 6838 Mar 9 2015 19:14:07 Tr_CD_st_uh2.KI Page 35
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary CRC Checksum File Size (bytes) Modified Date Time File Name 26871 9994 Mar 9 2015 20:57:50 Tr_CRD_st_dhl.KI 49184 9994 Mar 9 2015 22:28:22 Tr_CRD_st_dh2.KI 23505 9994 Mar 9 2015 17:48:41 Tr_CRD_st_uhl.KI 60584 9994 Mar 9 2015 19:19:32 Tr_CRD_st_uh2.KI 18031 8416 Mar 9 2015 21:01:51 Tr_CREJ_st_dhl.KI 08844 8416 Mar 9 2015 22:33:12 Tr_CREJ_st_dh2.KI 52638 8416 Mar 9 2015 17:52:46 Tr_CREJ_st_uhl.KI 40552 8416 Mar 9 2015 19:24:00 Tr_CREJ_st_uh2.KI 01489 7890 Mar 9 2015 21:05:35 Tr_FWC_st_dhl.KI 05454 7890 Mar 9 2015 22:37:41 Tr_FWC_st_dh2.KI 59732 7890 Mar 9 2015 17:56:33 Tr_FWC_st_uhl.KI 41752 7890 Mar 9 2015 19:28:39 Tr_FWC_st_uh2.KI 39983 5786 Mar 9 2015 21:08:10 Tr_HU_st_dhl.KI 44194 5786 Mar 9 2015 22:40:46 Tr_HU_st_dh2.KI 00116 5786 Mar 9 2015 17:59:10 Tr_HU_st_uhl.KI 24397 5786 Mar 9 2015 19:31:30 Tr_HU_st_uh2.KI 22332 1578 Mar 9 2015 21:08:28 Tr_HYDR_st_dhl.KI 58287 1578 Mar 9 2015 22:41:07 Tr_HYDR_st_dh2.KI 33547 1578 Mar 9 2015 17:59:28 Tr_HYDR_st_uhl.KI 34672 1578 Mar 9 2015 19:31:50 Tr_HYDR_st_uh2.KI 16128 7890 Mar 9 2015 21:12:12 Tr_IDPR_st_dhl.KI 58366 7890 Mar 9 2015 22:45:34 Tr_IDPR_st_dh2.KI 37100 7890 Mar 9 2015 18:03:14 Tr_IDPR_st_uhl.KI 05728 7890 Mar 9 2015 19:35:58 Tr_IDPR_st_uh2.KI 12377 14202 Mar 9 2015 21:19:22 Tr_ISl_st_dhl.KI 60741 14202 Mar 9 2015 22:54:12 Tr_ISl_st_dh2.KI 50307 14202 Mar 9 2015 18:10:30 Tr_ISl_st_uhl.KI 45145 14202 Mar 9 2015 19:43:57 Tr_ISl_st_uh2.KI 16826 7890 Mar 9 2015 21:23:06 Tr_IST_st_dhl.KI 20455 7890 Mar 9 2015 22:58:40 Tr_IST_st_dh2.KI 47038 7890 Mar 9 2015 18:14:18 Tr_IST_st_uhl.KI 04858 7890 Mar 9 2015 19:48:05 Tr_IST_st_uh2.KI 53576 2630 Mar 9 2015 21:23:58 Tr_LEAK_st_dhl.KI 63228 2630 Mar 9 2015 22:59:43 Tr_LEAK_st_dh2.KI 18199 2630 Mar 9 2015 18:15:10 Tr_LEAK_st_uhl.KI 13851 2630 Mar 9 2015 19:49:03 Tr_LEAK_st_uh2.KI 50913 13150 Mar 9 2015 21:30:34 Tr_LOF_st_dhl.KI 01496 13150 Mar 9 2015 23:07:38 Tr_LOF_st_dh2.KI 11614 13150 Mar 9 2015 18:21:52 Tr_LOF_st_uhl.KI 48527 13150 Mar 9 2015 19:56:23 Tr_LOF_st_uh2.KI 35510 8942 Mar 9 2015 21:34:53 Tr_LOP_st_dhl.KI 15662 8942 Mar 9 2015 23:12:49 Tr_LOP_st_dh2.KI Page 36
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary CRC Checksum File Size (bytes) Modified Date Time File Name 13722 8942 Mar 9 2015 18:26:14 Tr_LOP _st_uhl.KI 56332 8942 Mar 9 2015 20:01:10 Tr_LOP _st_uh2.KI 54380 9994 Mar 9 2015 21:39:45 Tr_LSB_st_dhl.KI 37299 9994 Mar 9 2015 23:18:39 Tr_LSB_st_dh2.KI 22926 9994 Mar 9 2015 18:31:11 Tr_LSB_st_uhl.KI 07182 9994 . Mar 9 2015 20:06:37 Tr_LSB_st_uh2.KI 31946 10520 Mar 9 2015 21:44:56 Tr_LSLD_st_dhl.KI 37662 10520 Mar 9 2015 23:24:52 Tr_LSLD_st_dh2.KI 28612 10520 Mar 9 2015 18:36:27 Tr_LSLD_st_uhl.KI 53332 10520 Mar 9 2015 20:12:24 Tr_LSLD_st_uh2.KI 46341 9468 Mar 9 2015 21:49:30 Tr_PL_st_dhl.KI 16512 9468 Mar 9 2015 23:30:22 Tr_PL_st_dh2.KI 43281 9468 Mar 9 2015 18:41:07 Tr_PL_st_uhl.KI 26618 9468 Mar 9 2015 20:17:29 . Tr_PL_st_uh2.KI 41536 9994 Mar 9 2015 21:54:23 Tr_PU_st_dhl.KI 30086 9994 Mar 9 2015 23:36:14 Tr_PU_st_dh2.KI 25843 9994 Mar 9 2015 18:46:03 Tr_PU_st_uhl.KI 30445 9994 Mar 9 2015 20:22:56 Tr_PU_st_uh2.KI 57260 7364 Mar 9 2015 21:57:49 Tr_RCPB_st_dhl.KI 45070 7364 Mar 9 2015 23:40:20 Tr_RCPB_st_dh2.KI 15759 7364 Mar 9 2015 18:49:33 Tr_RCPB_st_uhl.KI 19950 7364 Mar 9 2015 20:26:46 Tr_RCPB_st_uh2.KI 39199 10520 Mar 9 2015 22:03:00 Tr_RT_st_dhl.KI 02804 10520 Mar 9 2015 23:46:34 Tr_RT_st_dh2.KI 42095 10520 Mar 9 2015 18:54:48 Tr_RT_st_uhl.KI 17981 10520 Mar 9 2015 20:32:30 Tr_RT_st_uh2.KI 00064 8416 Mar 9 2015 22:07:02 Tr_SLD_st_dhl.KI 31844 8416 Mar 9 2015 23:51:23 Tr_SLD_st_dh2.KI 42805 8416 Mar 9 2015 18:58:53 Tr_SLD_st_uhl.KI 26036 8416 Mar 9 2015 20:36:59 Tr_SLD_st_uh2.KI 05984 8942 Mar 9 2015 22:11:21 Tr_SLl_st_dhl.KI 11211 8942 Mar 9 2015 23:56:34 Tr_SLl_st_dh2.KI 36053 8942 Mar 9 2015 19:03:15 Tr_SLl_st_uhl.KI 15136 8942 Mar 9 2015 20:41:48 Tr_SLl_st_uh2.KI 29896 7890 Mar 9 2015 22:15:09 Tr_SSB_st_dhl.KI 43498 7890 Mar 10 2015 0:01:02 Tr_SSB_st_dh2.KI 11972 7890 Mar 9 2015 19:07:02 Tr_SSB_st_uhl.KI 13532 7890 Mar 9 2015 20:45:59 Tr_SSB_st_uh2.KI 32334 6838 Mar 9 2015 22:18:19 Tr_TRT_st_dhl.KI 64867 6838 Mar 10 2015 0:04:50 Tr_TRT_st_dh2.KI 16300 6838 Mar 9 2015 19:10:15 Tr_TRT_st_uhl.KI 01608 6838 Mar 9 2015 20:49:30 Tr_TRT_st_uh2.KI Page 37
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary CRC Checksum
- File Size (bytes) Modified Date Time File Name 12170 845 Feb 10 2015 12:36:04 calc_k.mac
./Kl WRS:
21104 3300 Feb 10 2015 12:36:22 Get_SIF.mac 53662 2385 Mar 26 2015 17:38:40 SIF_Driver_WRS.mac 58341 342 Mar 26 2015 17:36:31 SIF_calc.inp 40929 342533 Mar 26 2015 17:40:17 SIF _calc.out 21270 864600 Mar 26 2015 16:42:36 WRS_JG.out 14702 1578 Mar 26 2015 17:39:55 WRS_dhl.KI 19074 1578 Mar 26 2015 17:40:16 WRS_dh2.KI 45110 1578 Mar 26 2015 17:39:17 WRS_uhl.KI 02636 1578 Mar 26 2015 17:39:37 WRS_uh2.KI 12170 845 Feb 10 2015 12:36:04 calc_k.mac
./Limit_Load:
43418 14478341 May 1 2015 7:52:06 BB_Head_Eighth_Symm_geom.inp 08136 2497 May 1 2015 7:53:31 BB_Head_LL.inp 14343 388270 May 1 2015 8:28:27 BB_Head_LL.out 24444 1183 May 1 2015 9:03:30 Sphere_LL. inp 34694 111381 May 1 2015 9:22:43 Sphere_LL.out 59712 12824244 May 1 2015 8:54:56 Sphere_geom.inp 52686 10355 Apr 9 2015 16:38:20 materials_LL.inp
./Model:
46075 9664611 Feb 9 2015 11:22:02 Base_Model.inp 08317 6653 Dec 16 2013 9:41:18 CrackFanMesh2.mac 50705 8654 Feb 10 2015 12:03:02 gen_crack_models.inp 55233 669743 Feb 23 2015 16:03:11 gen_crack_models.out 31314 9917 Dec 11 2013 17:45:05 materials.inp
./Spreadsheets:
21706 144488 May 1 2015 10:02:13 BB_Weld_Removed_Area.xlsx 30682 558077 Apr 8 2015 11:39:32 EPFM-RG1161_dh.xlsm 38937 557641 Apr 8 2015 11:22:11 EPFM-RG1161_uh.xlsm 32149 397032 Apr 8 2015 11:40:41 LEFM_FCG_dh.xlsm 04536 376452 Apr 8 2015 11:22:16 LEFM_FCG_uh.xlsm
./Verification/Post:
34097 14718 Mar 16 2013 18:00:53 vm143.dat 48177 100295 May 1 2015 10:17:48 vm143.out 39033 766 May 1 2015 10:17:48 vm143.vrt Page 38
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary CRC Checksum File Size (bytes) Modified Date Time File Name
./Verification/Pre:
34097 14718 Mar 16 2013 18:00:53 vm143.dat 41169 100534 Feb 23 2015 9:23:05 vm143.out 39033 766 Feb 23 2015 9:23:05 vm143.vrt Table 5-2: Computer Files for Rev 002 CRC Checksum File Size (bytes) Modified Date Time File Name
./Kl:
21104 3300 Feb 10 2015 12:36:22 Get_SIF.mac 39664 3414 Aug 24 2016 15:09:47 SIF_Driver.mac 14846 326 Feb 23 2015 10:06:44 SIF_calc.inp 48138 5868595 Aug 24 2016 15:48:25 SIF_calc.out 33487 12624 Aug 24 2016 15:40:48 Tr_EFT_st_dhl.KI 62660 12624 Aug 24 2016 15:48:24 Tr_EFT_st_dh2.KI 13457 12624 Aug 24 2016 15:27:33 Tr_EFT_st_uhl.KI 42858 12624 Aug 24 2016 15:34:29 Tr_EFT_st_uh2.KI 12170 845 Feb 10 2015 12:36:04 calc_k.mac
./Spreadsheets:
37043 580898 Sep 15 2016 16:12:23 EPFM-RG1161_dh_EFT.xlsm 58915 580927 Sep 9 2016 11:29:58 EPFM-RG1161_uh_EFT.xlsm 40908 402698 Sep 15 2016 16:12:29 LEFM_FCG_dh_EFT.xlsm 18412 379945 Sep 9 2016 11:29:45 LEFM_FCG_uh_EFT.xlsm
./Verification:
34097 14718 Mar 16 2013 18:00:53 vm143.dat 09679 100295 Aug 24 2016 15:14:41 vm143.out 39033 766 Aug 24 2016 15:14:41 vm143.vrt Page 39
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 6.0 CALCULATIONS 6.1 Stress Intensity Factors SIFs are calculated for each postulated crack front using the WRS and Section III stress results from the files listed in Table 4-10. The calculations are run by the ANSYS input file "SIF_calc.inp". The ANSYS macros "SIP_Driver.mac" and "SIF_Driver_WRS.mac" set the crack face boundary conditions, read in data from the stress models (WRS or Section III), and set up data arrays. The file "Get_SIF.mac" is used to perform stress mapping, solve the model with mapped stresses and then calculate the SIFs (using "calc_k.mac"). The SIF calculation results are written to the"* .KI" output files (see Table 5-1 ), which contain the SIFs for each step of a transient as well as a summary of the minimum and maximum SIF for the transient.
Upon reviewing the results of the uphill stress intensity factor calculations for the Design Condition it was seen that at positions near the bore (e.g., 16 and 17) the stress intensity factor is lower at crack front 2 than crack front 1; this is a result of the fact that stress results from the Section III model include additional constraint from the IDTB weld which is near the uphill crack front 2. In cases where the hillside angle is less steep the IDTB weld may not be as near to the J-groove weld. Therefore, it was decided that for conservatism the uphill crack front 2 results would not be used in calculations; instead, the stress intensity factors at flaw sizes larger than uphill crack front 1 will be conservfitively extrapolated using the scaling rule described in Section 2.1.
The simplified geometry of the postulated flaw shapes discussed in simplification 1 of Section 3 .3 results in low SIFs at some locations along the crack front (see tabulated values in Appendix A and Appendix B) such as at the "kink" at position 9 on the uphill side (Figure 2-2), and near the head ID surface at position 1 on the downhill side (Figure 2-3). The low values in these areas result because crack tip opening at these locations is restrained by other portions of the crack front due to the postulated flaw geometry. This has no impact on the results since these are not the controlling locations.
The boundary conditions utilized (Section 4.4.1) release the nodes on the crack face; in cases where there is compressive stress the crack face may close (i.e., move across the symmetry plane) producing positive SIFs where there should not be. For example, on uphill crack face 1, closure occurs only in one of the steps of the [ ]
transient. This closure results in small positive values ( [ ] at position 17) that are near the minimum.
The positive value predicted during closure would have a minor impact on the fatigue crack growth due to larger delta K, but with a beneficial effect of smaller R ratio. Very localized closure also occurs near the surface in transients such as a [ ] transient where there is a rapid increase in the temperature causing a compressive skin stress; in this case, the majority of the crack face remains open, and therefore would only be minimally affected. The overall effect on the analysis due to the small amount of crack face closure observed is minimal.
6.2 Fatigue Crack Growth Utilizing the SIF solutions described in Section 6.1, fatigue crack growth is calculated. The fatigue crack growth rule in Section 2.2 is integrated numerically using, The impact of the cycle increment (ilN) was investigated, and it was found that utilizing the number of cycles per year was a sufficiently small increment to accurately integrate the crack growth. Therefore, crack growth presented in this report has been calculated on a per year basis.
Page 40
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Based on review of the results, the stress intensity factors at position 17 at the nozzle bore on both the uphill and downhill side are typically largest. Exceptions to this occur in transients with rapid temperature drops which create high thermal stresses near the ID of the RVCH. The subsequent EPFM analyses will apply lower safety factors to these secondary stresses. Therefore, the nozzle bore locations are considered bounding and chosen for detailed evaluation. Fatigue crack growth calculations for position 17 on the uphill side and position 17 on the downhill side are performed in the spreadsheets "LEFM_FCG_uh.xlsm" and "LEFM_FCG_dh.xlsm" (see Table 5-1 ), and the detailed results are shown in Appendix A and Appendix B, respectively.
6.3 LEFM Evaluation LEFM evaluations are performed for the final flaw size from the fatigue crack growth evaluation. The applied SIF is evaluated accounting for the plastic zone correction described in Section 2.1.1, and its acceptability is evaluated based on the rules outlined in Section 2.3. The results for uphill position 17 and downhill position 17 are shown in Table 6-1 and Table 6-2, respectively.
Page 41
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table 6-1: Uphill Position 17 LEFM Results RTNDT [ ] OF Tc [ ] OF Upper ShelfToughness 200 ksh/in Initial Flaw Size, a1 [ ] in Final Flaw Size, a1 [ ] in Crack Growth, Ila r 1 in Loading Service Level Temperature (°F)
Pressure (psi)
Sy (ksi)
K,, (kshlin)
K1,(ksil/in)
K(a) (kshlin)
- a. (in)
K(a,) (in)
Margin = K,JK(a,)
Margin = K,./K(a,)
Required Margin Acceptable By LEFM?
Meets Tc Criterion for EPFM?
Page 42
Controiled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table 6-2: Downhill Position 17 LEFM Results RTNDT r l OF Tc [ l OF Upper ShelfToughness 200 ksivin Initial Flaw Size, a; [ ] in Final Flaw Size, a1 [ 1 in Crack Growth, 8a Loading
- [ ] in Service Level Temperature (°F)
Pressure (psi)
Sy (ksi)
K,,(ksMn)
K,,(ksMn)
K(a) (kshlin) a,(in)
K(a,) (in)
Margin = K1JK(a,)
Margin = K1./K(a,)
Required Margin Acceptable By LEFM?
Meets Tc Criterion for EPFM?
Page43
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Review of the results of Table 6-1 and Table 6-2 indicates that with few exceptions the LEFM acceptance criteria are not met; however, in all cases shown except the Hydrostatic test and the [ ] the temperature exceeds [ ] and may therefore be analyzed based on EPFM. The cases of the Hydrostatic test and the RCPB are addressed below.
For the Hydrostatic test case the LEFM results are not acceptable and the temperature considered of [ ]
does not meet the criteria to be analyzed by EPFM. Since the Hydrostatic test is a controlled event and the test temperature is chosen, a temperature of [ ] will be considered and EPFM analysis will be performed.
The Hydrostatic test case will be considered acceptable subject to meeting the EPFM requirements provided that Hydrostatic tests are performed with metal temperature of [ ] of greater.
The [ ] results listed in Table 6-1 and Table 6-2 also do not meet the LEFM criteria or the Tc criteria to be analyzed by EPFM; however, Table 6-1 and Table 6-2 have conservatively used the fluid temperature used in the Section III analysis and not the metal temperatures. For the uphill side the maximum stress intensity factor occurs at step 11, which from Table 6-4 of Reference [22] is a time of [ ] (note the downhill side maximum is earlier in the transient). From the detailed output in "Tr_RT_st.out" of Reference [22] at this time point the ID surface temperature is [ ] and the OD temperature is [ ] Linearly interpolating between the ID and OD, the temperature will with reach Tc at a depth of approximately [ ]
On both the uphill and downhill side crack tip 17 is ~eeper than [ ] and the metal temperature will exceed Tc. Therefore the EPFM evaluations will be performed considering a metal temperature equal to Tc.
6.4 EPFM Evaluations As noted in the previous section, the largest applied K is at the final flaw size; therefore, the EPFM evaluations will be performed for the final flaw size in accordance with the methodology described in Section 2.4 using the spreadsheets "EPFM-RG1161_uh.xlsm" and "EPFM-RG1161_dh.xlsm" (see Table 5-1). As discussed in the previous section all cases may be evaluated using EPFM. Table 6-3 and Table 6-4 provide the results of the EPFM evaluations. Note that when the higher safety factors provided in Section 3.1 of Code Case N-749 (Reference [3]) are used for the applied I-Integral criterion the stability check is not required; however, it is included here for completeness. As shown in Table 6-3 and Table 6-4, all cases meet the EPFM acceptance criteria. In all cases except for the [ ] transient on the downhill side the higher safety factors of Section 3 .1 of Reference [3] are used; the safety factors of Section 3 .2 of Reference [3] are used for the [ ]
transient on the downhill side. Details of the calculations for the limiting [ ] transient are provided in Appendix A and Appendix B, for the uphill and downhill side, respectively.
In the EPFM evaluations, the K due to pressure (K1p) is calculated based on the Design Condition results (Table A-2 and Table B-2). The Design Condition K is interpolated or extrapolated for the desired flaw size (see Section 2.1) and multiplied by the ratio of the transient pressure to the Design Pressure.
Page 44
Controiled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary
..... Table 6-3: Uphill Position 17 EPFM Results Loadino Service Level Temperature (°F)
Pressure (psi)
Applied J- Primary Safety Factor Integral Secondary Safety Factor Check J,"" (kips/in)
J (kics/inl Maroin = Jo 1/J'""
Required Maroins Applied J-lntegral Check Accectable?
Stabilitv Check Reauired?
Stability Primarv Safety Factor Check Secondarv Safetv Factor T,""
Trnsta llitv Man::iin = T1nstab111t/Teco Required Maroins Stabilitv Check Acceotable?
Page 45
Controi!ed Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Loadina
- Table 6-4: Downhill Position 17 EPFM Results Service Level Temnerature l'Fl Pressure losil Applied J- Primarv Safetv Factor Integral Secondary Safetv Factor Check J,-- lkios/inl J0 .1 lkios/in l Mara in= Jn 1/J.__
Renuired Marains Applied J-lntegral Check Acceotable?
Stability Check Reauired?
Stability Primarv Safetv Factor Check Secondarv Safetv Factor T---
Tin"tablllhl Marnin = T1nstab111t.ffa~~
Reauired Mara ins Stabi\itv Check Accentable?
Page 46
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary 6.5 Primary Stress Evaluation 6.5.1 Limit Load Finite Element Model The acceptance criterion of items 3.l(c) and 3.2(a)(3) of Reference [3] require that the primary stress limits of NB-3000 (Reference [24]) are met assuming a local area reduction of the pressure retaining membrane that is equal to the area of the flaw. As described in Section 2.5, the primary stress limits for design conditions (NB-3221.1, NB-3221.2, and NB-3221.3) need not be satisfied if it can be shown by performing a limit analysis (NB-3228.1) that the applied loadings do not exceed two-thirds of the lower bound collapse load. This condition is equivalent showing that the structure does not collapse at a pressure equal to 150% of the Design Pressure (1.5x
[ ] ). In terms of finite element results plastic collapse of the structure is equivalent to numerical instability.
The boundaries of the one nozzle model utilized for stress intensity factor calculations extend beyond half the distance between adjacent penetrations in some cases. As a result, the model cannot be used directly since it would potentially be taking credit for material that is needed to reinforce other penetrations; therefore, a new model has been developed considering a 45° sector of the head with all penetrations modeled. Since this is an approximation of the symmetry of the head an additional penetration is included to conservatively insure that the modeled configuration bounds all sectors. The model penetration layout is shown with the drawing in Figure 6-1.
Each CRDM penetration is modeled with a diameter of [ ] (Reference [15]) and the vent line penetration is modeled with a diameter of [ ] corresponding to the OD of the [ ] (Reference
[25]).
In order to represent the material removed by the postulated J-groove flaws and the crack growth the following method is used:
- A cut through the head is made at a depth of [ ] (center penetration max J-groove depth from base metal [12]) + [ ] (rounded up crack growth)= [ ] from the ID surface. This defines the depth of the metal removed.
- A cylindrical cut is made at each CRDM penetration to slice the material up to the [ ] depth.
This volume of material is removed to represent the area of the flawed J-groove welds. A diameter of
[ ] was selected for this cut. The cross-sectional area of these slices will be compared against the areas of the postulated flaws and projected crack growth later in this calculation to verify that this removes sufficient area.
The resulting model geometry with material removed is shown in Figure 6-2.
Page 47
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 6-1: Limit Load Model Penetration Layout Page 48
Controlled Docun1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 6-2: Limit Load Model Geometry The overall model geometry and mesh are defined in the input file "BB_Head_Eighth_Symm_geom.inp" (see Table 5-1). The model is meshed with SOLID185 elements with [
] The finite element mesh utilized is shown in Figure 6-3.
Page 49
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 6-3: Limit Load Model Finite Element Mesh The material properties for the analysis are defined in the file "materials_LL.inp". Note that the cladding and weld metal are excluded from the model since structural credit cannot be taken for the cladding and the weld metal is postulated to be flawed. The properties are identical to those used in the explicit crack models with the exception that the material has been changed to be elastic-perfectly plastic. The value of yield strength used is based on Sm (Reference [17]) the Design Temperature of [ ] and is given below.
RVCH (SA-533 Grade B Class 1) Sy= l.5Sm = 1.5(26.7 ksi) = 40.05 ksi Pressure is applied to the ID surface of the head and to the nozzle bores, incrementally increasing in each load J
step. Displacements normal to the three cut faces in the model are constrained. Additionally, end cap closure loads are accounted for by distributing the total load for each nozzle over the nozzle bore. The end cap loads are calculated using the following equation[
where P is the current applied pressure and dbore is the bore diameter. When a nozzle falls on a cutting plane an appropriate fraction of the total load is utilized (i.e., half on the symmetry planes and one eighth for the center penetration).
Page 50
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary The analysis is run using the input file "BB_Head_LL.inp" with results output to "BB_Head_LL.out". The output file shows the final converged load step at a pressure of [ ] which is equal to [ ] times the Design Pressure, which exceeds the requirement of 150% of the Design Pressure. The equivalent stress at the last converged load step is shown in Figure 6-4.
Figure 6-4: Equivalent Stresses at the Limit Pressure 6.5.1.1 Limit Load Methodology Verification In order to verify that the modeling methodology utilized can accurately predict limit loads, a simplified test case of a spherical shell was run, and will be compared with the theoretical solution. The same model geometry was taken prior to cutting holes for penetrations and meshed with SOLID 185 elements using similar mesh density and the same key options as the run described in 6.5.1. The model geometry and mesh are defined in the input file "Sphere_geom.inp". The finite element mesh for the test model is shown in Figure 6-5. The analysis is run by the input file "Sphere_LL.inp" (see Table 5-1).
Page 51
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 6-5: Finite Element Mesh for Limit Load Test Case From the output file "Sphere_LL.out" the final converged solution is at a pressure of [ ] The equivalent stress at the limit pressure is shown in Figure 6-6.
The theoretical limit pressure for an elastic-perfectly plastic sphere loaded by internal pressure is given by (see e.g., Reference [26])
where PL is the limit pressure, cry is the yield strength, R0 is the outer radius, and Ri is the inner radius. For the test problem using the shell geometry described in Section 4.1this results in Page 52
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary The finite element model predicted limit load of [ ] psig is equal to 99.5% of the theoretical solution above, which shows that the methodology utilized can accurately predict limit loads.
Figure 6-6: Limit Load Test Case Equivalent Stress at Limit Pressure 6.5.2 Calculation of Flaw Area Removed The cross-sectional areas of the material removed to represent the postulated J-groove flaws plus crack growth diagr[ J (see Figure 2-2 and Figure 2-3) on the uphill side and downhill side are calculated using the following equation (see for Figure 6-7 where x is the horizontal distance from the vessel centerline, R 1 is the inside radius of the vessel, and R 2 is the radius to the depth of the metal removed. In Figure 6-7, the area removed to represent the uphill flaw is indicated by area A2 and the downhill flaw by area A3. The integral is evaluated using the following solution from a table of integrals (e.g., Reference [27])
Page 53
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 6-7: Area Calculation Diagram The area removed from the ANSYS model is calculated in the spreadsheet "BB_Weld_Removed_Area.xlsx" (see Table 5-1) for the center penetration (1) and the outermost penetrations (74-78) since these will bound the minimum (center) and maximum (outermost) areas. The resulting areas removed from the ANSYS model are shown in Table 6-5.
Page 54
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table 6-5: Model Areas Removed by the Cutouts to Represent Postulated Flaws i
__ .... _. Nozzles
-****-- -******- -*--****- ---****** ___...... ~-**** .. -~"***- --*** - _._ .... __ --..... - --***** - --**~-- ---****- --****- ---*-----***- ~-**
- -* --*--- *- ..... ---* ___ ,,., -- ---- -- ,,,_.. _____ .,__ -- ,_,_,______ - ......_ ..___ t* 74 75
- ~* .,,_----~--*--- ***~--*
i 76
- -~-..-- ------- -----. - -~*-* ._ *-*~------
- ------- ------- ......... ----*---*--*---- -~---****.
- 77 Geometry Inputs Rl (RVCH inner radius to base metal) i j
inches
-, 1 78 "l'-
R2 (Rl + J-groove depth+ crack growth) inches dbore (nozzle bore diameter) inches Cx (x distance from RVCH CL to Nozzle CL) inches Cy (y distance from RVCH CL to Nozzle CL) inches Rh= (CxA2+CyA2)A0.5 inches Ll (distance from nozzle CL to cut radius) inches L2 (distance from nozzle CL to cut radius) inches icalculate Area, A2 (Uphill Weld Area Removed) '
I xmin = Rh-Ll inches xmax = Rh-dbore/2 inches A2 square inches
- Calculate Area, A3 (Downhill Weld Area Removed) !
xmin = Rh+dbore/2 inches xmax = Rh+L2 inches A3 square inches
!Calculate total weld cross sectional area removed in model A2+A3 square inches For the outermost penetration the initial flaw areas are measured from the ANSYS workbench model to be
[ ] in2 on the uphill side and [ ] on the downhill side (see Figure 6-8). For the center penetration the initial flaw area on both the uphill and downhill side is conservatively estimated by taking rectangle bounding the J-groove and butter (Reference [12]).
[ ]
The area with crack growth is estimated by taking the square root of the area, adding a rounded up crack growth of [ ] (see Table 6-1 and Table 6-2), and squaring the result as illustrated schematically in Figure 6-9. The results of the calculation are shown in Table 6-6.
Page 55 I
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 6-8: Outermost Penetration Crack Face Areas Page 56
Controlled Docun1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 6-9: Crack Growth Area Calculation Table 6-6: Flaw Area Comparison Nozzle Center Nozzle Outermost Nozzle 2
Uphill Weld Area in 2
Downhill Weld Area in Max Crack Growth inches 2
Uphill Weld Area with Max Crack Growth in 2
Downhill Weld Area with Max Crack Growth in 2
Uphill Area Removed, A2 in 2
Downhill Area Removed, A3
- in 2
Uphill Area Removed - Uphill Area with Max CG in 2
Downhill Area Removed - Downhill Area with Max CG in As shown above in Table 6-6 the areas removed from the ANSYS model (A2 and A3) exceeds the area including crack growth in all cases; therefore, sufficient area has been removed in the Limit Load model to account for the area of the flaw and crack growth.
Since sufficient area has been removed and the limit pressure exceeded 150% of the Design Pressure, the primary stress criteria in items 3. l(c) and 3.2(a)(3) of Code Case N-749 (Reference [3]) are satisfied.
Page 57
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary
7.0 CONCLUSION
S A fatigue crack growth and fracture mechanics evaluation of the worst-case flaws in the as-left J-groove weld and buttering at the worst-case penetration location has been 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.
Limitation: The minimum metal temperature for performing a Hydrostatic test at any time after an IDTB repair has been made is [ ]
Page 58
Controlled Docun1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary
8.0 REFERENCES
- 1. AREVA Document 08-9232121-001, "Byron Units 1and2, and Braidwood Units 1and2, RVCH Nozzle Penetration Modification."
- 2. ASME Boiler and Pressure Vessel Code,Section XI, "Rules for Inservice Inspection of Nuclear Power Plant Components", 2001 Edition including Addenda through 2003.
- 3. Cases of the ASME Boiler and Pressure Vessel Code, Case N-749, "Alternative Acceptance Criteria for Flaws in Ferritic Steel Components Operating in the Upper Shelf Temperature Range,"Section XI, Division I.
- 4. Letter, Balwant K. Singal (NRC) to Randall K. Edington (APS), "Palo Verde Nuclear Generating Station, Unit 3- Request for Additional Information RE: Relief Request 52, Alternative to ASME Code,Section XI Requirements for Flaw Evaluation, Flaw Characterization, and Successive Examinations (TAC NO.
MF4169)," NRC ADAMS Accession Number ML14330A510, December 4, 2014.
- 5. T.L. Anderson, "Fracture Mechanics - Fundamentals and Applications", CRC Press, 1991.
- 6. AREVA Document 38-2201373-001, "Byron Units 1&2 and Braidwood Units 1&2 Proprietary Information."
- 7. AREVA Drawing 02-185313E-OO, "Closure Head Assembly."
- 8. AREVA Drawing 02-185314E-OO, "Closure Head Sub-Assembly Sheet 1."
- 9. AREVA Drawing 02-185344E-OO, "Closure Head Assembly."
- 10. AREVA Drawing 02- l 8~345E-OO, "Closure Head Sub-Assembly Sheet l ."
- 11. AREVA Drawing 02-184573E-04, "Closure Head Assembly."
- 12. AREVA Drawing 02-184574E-06, "Closure Head Sub-Assembly Sheet 1."
- 13. AREVA Drawing 02-185282E-OO, "Closure Head Assembly."
- 14. AREVA Drawing 02-185283E-01, "Closure Head Sub-Assembly Sheet l."
- 15. AREVA Drawing 02-9232823E-001, "Byron Units 1and2 I Braidwood Units 1and2 CRDM, SPARE &
RVLIS Penetration Modification."
- 16. AREVA Drawing 02-9232824E-001, "Byron Units 1 and 2 I Braidwood Units 1 and 2 Thermocouple Column Penetration Modification."
- 17. ASME Boiler and Pressure Vessel Code,Section III, "Nuclear Power Plant Components," Division 1, 1971 Edition including Addenda through Summer 1973
- 18. AREVA Document 51-9234885-000, "Exelon Byron and Braidwood RVCH Original Material and Fabrication Review."
- 19. ASTM E185-10, "Standard Practice for Design of Surveillance Programs for Light-Water Moderated Nuclear Power Reactor Vessels."
- 20. Regulatory Guide 1.161, "Evaluation of Reactor Pressure Vessels with Charpy Upper-Shelf Energy Less than 50 ft-lb, June 1995.
- 21. AREVA Document 32-9233779-000, "Weld Residual Stress Analysis of Byron 1 & 2, and Braidwood 1
& 2 RVCH Nozzle/Penetration Repair"
- 22. AREVA Document 32-9233803-001, "ASME Section III Analysis of Byron/Braidwood RVCH Nozzle and Penetration Modification"
- 23. ANSYS Finite Element Computer Code, Version 14.5, ANSYS Inc., Canonsburg, PA.
- 24. ASME Boiler and Pressure Vessel Code,Section III, "Rules for Construction of Nuclear Facility Components", Division 1, 2001 Edition including Addenda through 2003.
- 25. AREVA Drawing 02- l 853l8E-O1, "Closure Head Attachments."
- 26. Hill, R., "The Mathematical Theory of Plasticity," Oxford University Press, 1950.
- 27. Avalone, E.A., Baumeister, T., Sadegh, A.M., (Eds.) "Marks' Standard Handbook for Mechanical Engineers," Eleventh Edition, McGraw Hill.
Page 59
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary
- 28. ASME Boiler and Pressure Vessel Code,Section XI, "Rules for Inservice Inspection of Nuclear Power Plant Components, 2007 Edition including Addenda through 2008.
- 29. Federal Register, Volume 81, Page 10787 (81FR10787), Wednesday March 2, 2016, Proposed Rules.
Page 60
Controlled Docun1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary APPENDIX A: UPHILL SIDE FLAW EVALUATIONS This appendix presents the fatigue crack growth and flaw evaluations for the uphill side flaw.
Table A-1: SIFs for Uphill Side - Welding Residual Stress Page A-1
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-2: SIFs for Uphill Side - Design Condition Page A-2
Controlled Docurnent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-3: SIFs for Uphill Side - [ ]
Page A-3
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-4: SIFs for Uphill Side - [ ]
Page A-4
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-5: SIFs for Uphill Side - [ ]
Page A-5
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-6: SIFs for Uphill Side - [ ]
Page A-6
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-7: Fatigue Crack Growth for [ ] (Uphill)
PageA-7
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-8: Fatigue Crack Growth for [ ] (Uphill)
PageA-8
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-9: Fatigue Crack Growth for [ ] (Uphill)
Page A-9
Controlled Document A.
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-10: Fatigue Crack Growth for [ ] (Uphill)
Page A-10
Controlled Document A.
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-11: Fatigue Crack Growth [ ] (Uphill)
Page A-11
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-12: Fatigue Crack Growth for [ ] (Uphill)
Page A-12
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-13: Fatigue Crack Growth for [ ] (Uphill)
Page A-13
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-14: Fatigue Crack Growth for [ I (Uphill)
Page A-14
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-15: Fatigue Crack Growth for [ ] (Uphill)
PageA-15
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-16: Fatigue Crack Growth for [ ](Uphill)
Page A-16
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-17: Fatigue Crack Growth for [ ] (Uphill)
PageA-17
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-18: Fatigue Crack Growth for [ ] (Uphill)
PageA-18
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-19: Fatigue Crack Growth for [ ] (Uphill)
Page A-19
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-20: Fatigue Crack Growth for [ ] (Uphill)
PageA-20
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-21: Fatigue Crack Growth for [ ] (Uphill)
Page A-21
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table A-22: EPFM Evaluation for [ ] (Uphill)
Page A-22
Controlled Docun1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure A-1: J-T Diagram for [ ] (Uphill)
Page A-23
Controlled Docun1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary APPENDIX B: DOWNHILL SIDE FLAW EVALUATIONS This appendix presents the fatigue crack growth and flaw evaluations for the downhill side flaw.
Table B-1: SIFs for Downhill Side - Welding Residual Stress Page B-1
Controlled Docurr1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table 8-2: SIFs for Downhill Side - Design Condition Page B-2
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-3: SIFs for Downhill Side - [ ]
Page B-3
l Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-4: SIFs for Downhill Side - [ ]
Page B-4
Controlled Docu1T1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-5: SIFs for Downhill Side - [ ]
Page B-5
Controlled Docu1T1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-6: SIFs for Downhill Side - [ ]
Page B-6
Controlled Document A.
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-7: Fatigue Crack Growth for [ ] (Downhill)
Page B-7
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-8: Fatigue Crack Growth for [ ] (Downhill)
Page B-8
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-9: Fatigue Crack Growth for [ ] (Downhill)
Page B-9
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-10: Fatigue Crack Growth for [ ] (Downhill)
Page B-10
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-11: Fatigue Crack Growth for [ ] (Downhill)
Page B-11
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-12: Fatigue Crack Growth for [ ] (Downhill)
Page B-12
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-13: Fatigue Crack Growth for [ ] (Downhill)
Page B-13
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-14: Fatigue Crack Growth for [ ] (Downhill)
Page B-14
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-15: Fatigue Crack Growth for [ ] (Downhill)
Page B-15
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-16: Fatigue Crack Growth for [ ] (Downhill)
Page B-16
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-17: Fatigue Crack Growth for [ ] (Downhill)
Page B-17
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-18: Fatigue Crack Growth for [ ] (Downhill)
Page B-18
Controiled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-19: Fatigue Crack Growth for [ ] (Downhill)
Page B-19
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-20: Fatigue Crack Growth for [ ] (Downhill)
Page B-20
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-21: Fatigue Crack Growth for [ ] (Downhill)
Page B-21
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table B-22: EPFM Evaluation for [ ] (Downhill)
Page B-22
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Figure 8-1: J-T Diagram for [ ] (Downhill)
Page B-23
Controlled Docun1ent A
AREV,A Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary APPENDIX C: EVALUATION OF THE [ ]
TRANSIENT C.1 Purpose The purpose of this appendix is to evaluate the [ ] defined in Reference [6] (TODI BYR-16-023).
C.2 Evaluation Transient stresses for the [ ] were developed in Reference [22] (file [ ] ), and applied to the explicit flaw models as described in the main body of this report to determine stress intensity factors. The computer files for this run are documented in Table 5-2. The resulting minimum and maximum stress intensity factors for this transient from the "*.KI" files (Table 5-2) are listed in Table C-1 for the uphill side and Table C-2 for the downhill side.
Table C-1: SIFs for Uphill Side - [ ]
Page C-1
Coniro!led Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table C-2: SIFs for Downhill Side - [ ]
The [ ] has [ ] design cycles and is an [ ] condition per Reference [6] (TODI BYR-16-023).
From Table C-1 at position 17 on the uphill side [ ] , and from Table C-2 at position 17 for the downhill side [ ] . Based on these stress intensity factor ranges, and comparison with the crack growth results presented in Appendix A and Appendix B, [ ] cycles of [ ] would result in crack growth of only a few mils; this growth is negligible relative to the large postulated flaw sizes and the existing calculated crack growth. Therefore, the fatigue crack growth analysis need not consider the [ ] , and final flaw sizes calculated in the main body (see Table 6-1 and Table 6-2) remain applicable with the inclusion of the
[ ] transient.
The LEFM evaluations described in Section 6.3 are performed for the uphill position 17 and downhill position 17 in spreadsheets "LEFM_FCG_uh_EFT.xlsm" and "LEFM_FCG_dh_EFT.xlsm" (see Table 5-2). The results are summarized in Table C-3 and Table C-4. Similar to the other transient LEFM analyses in Section 6.3, the LEFM acceptance criteria are not satisfied, however the temperature is in the upper shelf range(> Tc), and therefore EPFM methodology is applicable.
Page C-2
Controlled Docun1ent A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table C-3: Uphill Position 17 [ ] LEFM Results Table C-4: Downhill Position 17 [ ] LEFM Results Page C-3
Controlled Docun1ent A
.AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary The EPFM analyses are perfomed in the spreadsheets "EPFM-RG1161_uh_EFT.xlsm" and "EPFM-RG 1161_dh_EFT.xlsm" (see Table 5-2) following the methodology described in the main body of the report.
The results are summarized in Table C-5 and Table C-6 for the uphill and downhill sides, respectively. In both cases, considering the higher safety factors provided in Section 3.1 of Reference [3], the applied J-Integral is less than the material J-Integral at a ductile crack extension of 0.1 in. Although not required with use of the safety factors from Section 3 .1 of Reference [3] for the applied J-Integral check, the stability check is performed for completeness and is also satisfied.
Table C-5: Uphill Position 17 [ ] EPFM Results Page C-4
Controlled Document A
AREVA Document No. 32-9244434-002 Byron and Braidwood RVCH Nozzle As-Left J-Groove Analysis- Non Proprietary Table C-6: Downhill Position 17 [ ] EPFM Results C.3 Conclusion Based on the evaluation above, the [ ] transient satisfies the acceptance criteria of Code Case N-749 (Reference [3]) for the remaining life of the postulated flaws.
Page C-5