ML071620388
| ML071620388 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek  |
| Issue date: | 06/01/2007 |
| From: | Broussard J, Collin J, White G Dominion Engineering |
| To: | Office of Nuclear Reactor Regulation |
| References | |
| Download: ML071620388 (163) | |
Text
Advanced FEA Crack Growth Calculations for Evaluation of PWR Pressurizer Nozzle Dissimilar Metal Weld Circumferential PWSCC Sponsored by: EPRI Materials Reliability Program Presented To:
Expert Review Panel for Advanced FEA Crack Growth Calculations Presented By:
Glenn White John Broussard Jean Collin Dominion Engineering, Inc.
Thursday, May 31 and Friday, June 1, 2007 11730 Plaza America Dr. #310 Meeting on Implications of Wolf Creek Dissimilar Metal Weld Inspections Reston, VA 20190 703.437.1155 DEI Offices www.domeng.com Reston, Virginia
Thursday Morning Agenda Introductions - Industry and NRC Status of Industry Work (Industry)
- Update on Weld Fabrication/Repair Information
- WRS Modeling
- EPFM vs. Limit Load Issue Update
- Primary and Secondary Stress Inclusion Issue Update
- K Validation
- Model Convergence
- Update on Timeline of Activities
- WRS Modeling
- Validation Studies
- Leak-Rate Studies Status of NRC Confirmatory Research (NRC)
- K Validation
- Model Convergence
- Update on Timeline of Activities
- WRS
- Phase II Sensitivity Studies
- Validation Studies
- Leak-Rate Studies 2 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Thursday Afternoon Agenda Presentation & Discussion of Proposed Sensitivity Matrix (Industry)
- List of Sensitivity Matrix Cases that Industry will Evaluate
- Loads/Geometries/WRS/CGR/Multiple Crack Growth 3 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Friday Agenda Discussion of Proposed Sensitivity Matrix (Industry & NRC)
Proposed Acceptance Criteria and Safety Factors (Industry)
Plans for next meeting(s) (Industry & NRC)
Meeting Summary and Conclusions (Industry & NRC) 4 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Thursday Morning Agenda Introductions - Industry and NRC Status of Industry Work (Industry)
Status of NRC Confirmatory Research (NRC) 5 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Principal Meeting Participants EPRI Project Management / Support NRC Participants
- Craig Harrington, EPRI - Al Csontos, NRC Research
- Tim Gilman, Structural Integrity Associates - Mauricio Gutierrez, NRC NRR Project Team - Tim Lupold, NRC NRR
- Glenn White, DEI - Dave Rudland, EMC2
- John Broussard, DEI - Simon Sheng, NRC NRR
- Jean Collin, DEI - Ted Sullivan, NRC NRR Expert Review Panel
- Ted Anderson, Quest Reliability, LLC (via phone)
- Warren Bamford, Westinghouse
- Doug Killian, AREVA
- Cameron Martin, Westinghouse
- Pete Riccardella, Structural Integrity Associates 6 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Status of Industry Work Topics Update on Weld Fabrication/Repair Information WRS Modeling EPFM vs. Limit Load Issue Update Primary and Secondary Stress Inclusion Issue Update K Validation Model Convergence Update on Timeline of Activities
- WRS Modeling
- Validation Studies
- Leak-Rate Studies 7 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Update on Weld Fab/Repair Information Summary A summary of the previously compiled weld repair information is shown on the next two slides Warren Bamford and Cameron Martin of Westinghouse to present the update
- Weld fabrication
- Weld repair 8 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Weld Fab/Repair Information PRELIMINARY Weld Repair Summary Table
- Defect Defect/Repair Defect/Repair Defect/Repair Defect/Repair Defect/Repair Defect/Repair ID/OD Alloy PWHT or Area #1 Area #2 Area #3 Area #4 Area #5 Area #6 Table Plant Nozzle Nozzle Design Buttering (% 82 or after Repair Length Depth Length Depth Length Depth Length Depth Length Depth Length Depth Line Code Type Count # or Weld circ.) 182 Repair? Areas (in.) (in.) (in.) (in.) (in.) (in.) (in.) (in.) (in.) (in.) (in.) (in.)
1 A Safety A 1 1a weld OD N/A N/A 4 N/A ~1/2 N/A ~1/2 N/A ~1/2 N/A ~1/2 2 A Safety B 2 1a weld ID N/A N/A 1 1/2 5/8 3 E Relief 3 1a weld OD N/A N N/A N/A N/A 4 E Safety C 4 1a weld ID<22% N/A N N/A N/A N/A 5 ID 82 Y N/A N/A N/A H Safety A 5 1a weld 6 OD 82 Y N/A N/A N/A 7 F Safety A 6 1b NR NR NR NR NR NR NR 8 B Relief 7 2a weld OD 182 N/A 1 0.5 0.375 9 C Safety A 8 2b NR NR NR NR NR NR NR 10 C Safety B 9 2b NR NR NR NR NR NR NR 11 C Safety C 10 2b NR NR NR NR NR NR NR 12 D Safety A 11 3 butter N/A N/A Y N/A N/A N/A 13 butter ID 82 Y N/A N/A ~0.3 E Spray 12 4 14 weld OD N/A N N/A N/A N/A 15 C Spray 13 5 NR NR NR NR NR NR NR 16 ID N/A N/A 5 1.5 5/16 3.75 0.5 2 3/16 2.5 5/16 2 5/16 A Surge 14 8 weld 17 OD N/A N/A 3 2.5 0.5 2 0.5 1 3/16 18 E Surge 15 8 weld ID<10% 82 N 3 N/A N/A N/A N/A N/A N/A 19 butter N/A 82 Y 1 N/A N/A 20 OD 182 N/A 2 1.75 0.875 1.5 1 B Surge 16 8 21 weld ID 182 N/A 1 1.0 0.625 22 ID 182 N/A 1 4 0.75 Notes:
- 1. For Designs #2a, #2b, and #5, liner directly covers DM weld.
- 2. For Design #4, liner does not extend to most of DM weld.
- 5. NR = Information not yet reported (or may not be available)
- 6. N/A = Information not available
- 7. Weld repair entries for Plants C and F are preliminary.
9 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Weld Fab/Repair Information PRELIMINARY Weld Repair Summary Table (contd)
- Defect Defect/Repair Defect/Repair Defect/Repair Defect/Repair Defect/Repair Defect/Repair ID/OD Alloy PWHT or Area #1 Area #2 Area #3 Area #4 Area #5 Area #6 Table Plant Nozzle Nozzle Design Buttering (% 82 or after Repair Length Depth Length Depth Length Depth Length Depth Length Depth Length Depth Line Code Type Count # or Weld circ.) 182 Repair? Areas (in.) (in.) (in.) (in.) (in.) (in.) (in.) (in.) (in.) (in.) (in.) (in.)
WC1 N/A 82/182 Y N/A N/A N/A WC2 ID+OD 82 Y 2 1/2 7/16ID 1 7/16OD WC3 butter OD 182 Y 1 1 3/4 WC4 J Relief WC1 1a ID 82 Y 3 3/4 3/4 2-1/4 3/4 1/2 3/4 WC5 OD 182 Y 3 1 3/4 2-1/4 3/4 1/2 3/4 WC6 OD 82 N/A 1 1-1/4 1/2 weld WC7 ID 82 N/A 1 1/2 1/2 WC8 butter N/A 182 Y N/A N/A 1/8 J Safety A WC2 1a WC9 weld ID 82 N/A 2 1-1/4 11/32 7/8 11/32 WC10 82 N/A 6 2-1/2 3/4 1 1/2 1-1/2 1/2 1 1/2 2-1/2 3/4 2-1/2 3/4 J Safety B WC3 1a weld ID WC11 82 N/A 6 1-1/2 1/2 1-1/4 1 3/4 7/8 1-1/2 3/8 1 1-1/16 1/2 1/2 WC12 J Spray WC4 4 butter lip/bondline 82 Y N/A N/A N/A WC13 butter OD 182 Y 2 7/8 9/16 1-1/8 1 J Surge WC5 8 WC14 weld ID 82 Y 1 1 7/16 Notes:
- 1. For Designs #2a, #2b, and #5, liner directly covers DM weld.
- 2. For Design #4, liner does not extend to most of DM weld.
- 5. NR = Information not yet reported (or may not be available)
- 6. N/A = Information not available
- 7. Weld repair entries for Plants C and F are preliminary.
10 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Modeling Introduction DEI is currently running the WRS cases discussed at the May 1 and May 8 meetings
- See slides that follow We also have examined the MRP-106 WRS results in greater detail:
- Generic MRP-106 surge nozzle case
- Generic MRP-106 safety and relief nozzle case
- New figures to be presented separate from this presentation package 11 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Welding Residual Stress (WRS) Analysis Case Matrix May 1 and May 8 meetings identified key geometry cases for consideration Surge Nozzle
- No repairs with fill-in weld
- 0.5 (or 5/16) repair followed by fill-in weld
- CE nozzle case with no fill-in weld Safety/Relief Nozzle
- No repairs with safe end ID weld buildup
- No repairs with liner fillet weld
- 3/4" deep ID repair followed by liner fillet weld Spray Nozzle
- Cases deferred until further information available 12 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Analysis Cases Completed Surge Nozzle
- Type 8 (Westinghouse) base case, includes fill-in weld
- Type 8 with 5/16" ID repair (fill-in weld follows repair)
Safety/Relief Nozzle
- Type 1a (clad, no liner) base case
- Type 2b (liner with fillet weld) base case
- Type 1a with safe end ID weld buildup All cases analyzed with safe end to pipe butt weld
- Initial cases indicated noticeable effect of butt weld, therefore included in all cases for completeness 13 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 8 Surge Nozzle - Model Dimensions 18.28" 17.85" 17.40" 17.02" 16.43" 16.14" 15.99" 13.81" 13.34" 12.66" 11.25" 8.00" 0.94" 13.00" 0.31" 12.81" 13.34" 9.50" 0.75" 7.50" 0.62" 7.00" 6.22" 0.25" 5.99" 5.92" 5.60" 5.75" 5.60" 14 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 8 Surge Nozzle - Weld Region Detail Alloy 182 DMW Butter Safe Nozzle End SS Weld Pipe Clad Fill-in Repair Weld 15 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 8 Surge Nozzle (Base Case)
Starting Model DMW (11 +1 layers) Followed by Fill-in Weld (4 layers)
Model Complete 16 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 8 Surge Nozzle Weld Sequence DMW: 11 layers built on initial land of material DMW: Initial land removed then welded as 12th pass Fill-in Weld: 4 layers built out Safe end to pipe: 7 layers built on initial land of material
- Initial land not removed and welded ID repair performed in 4 layers prior to Fill-in Weld step 17 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 8 Surge Nozzle Model - Element Mesh and Weld Layers 18 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 1a Safety/Relief Nozzle - Model Dimensions 11.37" 11.11" 10.61" 10.21" 10.02" 9.47" 8.79" 8.54" 8.16" 7.86" 7.53" 6.60" 4.00" 5.50" 4.00" 3.75" 3.31" 2.78" 2.59" 2.46" 19 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 1a Safety/Relief Nozzle - Weld Region Detail Alloy 182 DMW Nozzle Butter Safe SS Weld End Pipe Clad Safe End ID Buildup 20 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 1a Safety/Relief Nozzle Model Safe End ID Weld 21 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 1a Safety/Relief Nozzle Weld Sequence DMW: 11 layers built on initial land of material DMW: Initial land removed then welded as 12th pass Safe end to pipe: 9 layers built on initial land of material
- Initial land not removed and welded Safe end ID weld buildup performed in 2 layers prior to safe end to pipe weld step 22 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 2b Safety/Relief Nozzle - Weld Region Detail Alloy 182 DMW Nozzle Butter Safe End SS Weld Pipe Liner Liner Fillet Weld Liner Fillet Weld performed after DMW complete, prior to SS weld 23 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 2b Safety/Relief Nozzle Model Liner Fillet Weld 24 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 1a Safety/Relief Results - Base Case - Axial Stresses Weld C/L After Weld Out After Back Weld After SS Weld After Hydro Operating 80,000 60,000 40,000 20,000 Axial Stress (psi) 0
-20,000
-40,000
-60,000
-80,000 0.000 0.100 0.200 0.300 0.400 0.500 0.600 0.700 0.800 0.900 1.000 a/t 25 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 1a S/R Results - Safe End ID Weld - Axial Stresses Weld C/L After Back Weld After Safe End ID After SS Weld After Hydro Operating 80,000 60,000 40,000 20,000 Axial Stress (psi) 0
-20,000
-40,000
-60,000
-80,000 0.000 0.100 0.200 0.300 0.400 0.500 0.600 0.700 0.800 0.900 1.000 a/t 26 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 2b Safety/Relief Results - Base Case - Axial Stresses Weld C/L After Back Weld After Fillet Weld After SS Weld After Hydro Operating 80,000 60,000 40,000 20,000 Axial Stress (psi) 0
-20,000
-40,000
-60,000
-80,000 0.000 0.100 0.200 0.300 0.400 0.500 0.600 0.700 0.800 0.900 1.000 a/t 27 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 8 Surge Nozzle Results - Base Case - Axial Stresses Weld C/L After Weld Out + Fill-in After SS Weld After Hydro Operating 80,000 60,000 40,000 20,000 Axial Stress (psi) 0
-20,000
-40,000
-60,000
-80,000 0.000 0.100 0.200 0.300 0.400 0.500 0.600 0.700 0.800 0.900 1.000 a/t 28 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Type 8 Surge Nozzle Results - ID Repair - Axial Stresses Weld C/L After Weld Out + Fill-in After SS Weld After Hydro Operating 80,000 60,000 40,000 20,000 Axial Stress (psi) 0
-20,000
-40,000
-60,000
-80,000 0.000 0.100 0.200 0.300 0.400 0.500 0.600 0.700 0.800 0.900 1.000 a/t 29 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
WRS Analysis Overall Operating Condition Summary - Axial Stresses Weld C/L Type 1a (S/R) base Type 1a (S/R) Safe End ID Type 2b (S/R) base Type 8 (Surge) base Type 8 (Surge) ID repair 80,000 60,000 40,000 20,000 Axial Stress (psi) 0
-20,000
-40,000
-60,000
-80,000 0.000 0.100 0.200 0.300 0.400 0.500 0.600 0.700 0.800 0.900 1.000 a/t 30 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
EPFM vs. Limit Load Issue Update Summary Experimental data for failure of complex cracks in pipes have been evaluated to investigate limit load prediction vs.
maximum experimental load DPZP proposed for complex cracks has been used to plot the results of the comparison Approach covered in May 8 presentation by Pete Riccardella of Structural Integrity Associates Work to evaluate apparent toughness data for complex crack tests using enhanced reference stress (ERS) approach by Kim still in progress
- Challenge is to calculate elastic J-integral for test complex crack geometry 31 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
EPFM vs. Limit Load Issue Update Max Experimental Moment Divided by NSC Predicted Moment 1.4 1.3 1.2 1.1 Max Experimental Moment / NSC Predicted Moment GAM-400 (SS TIG) 4113-2 (304SS) 1.0 4113-1 (304SS) 4114-3 (304SS) 0.9 12IRS (304SS) 4114-4 (304SS)
GAM-600 (SS TIG) 4113-3 (Alloy 600) 0.8 4114-2 (304SS) 4113-6 (A106B CS) 4113-4 (Alloy 600) 4113-5 (A106B CS) 0.7 4114-1 (A106B CS) 0.6 0.5 0.4 0.3 Crack Not Take Compression Crack Take Compression 0.2 Complex crack test data 0.1 0.0 0 1 2 3 4 5 6 7 8 9 10 11 12 DPZP 32 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
EPFM vs. Limit Load Issue Update NSC Predicted Moment Divided by Max Experimental Moment 1.5 4114-1 (A106B CS) 1.4 4113-5 (A106B CS) 4113-6 (A106B CS) 1.3 4114-2 (304SS) 4113-4 (Alloy 600) 1.2 GAM-600 (SS TIG) 4113-3 (Alloy 600)
NSC Predicted Moment / Max Experimental Moment 4114-4 (304SS) 1.1 12IRS (304SS) 4114-3 (304SS) 4113-1 (304SS) 1.0 GAM-400 (SS TIG) 4113-2 (304SS) 0.9 0.8 0.7 0.6 GAM-1100 (SS TIG) 0.5 0.4 Crack Not Take Compression 0.3 Crack Take Compression 0.2 Complex crack test data 0.1 0.0 0 1 2 3 4 5 6 7 8 9 10 11 12 DPZP 33 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Secondary Stress Inclusion Issue Update Introduction See presentations on this topic by
- Ted Anderson of Quest Reliability, LLC on elastic-plastic FEA calculations of response of pipe with through-wall crack to fixed end rotation
- Pete Riccardella of Structural Integrity Associates on surge line rotation study 34 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
K Validation Introduction FEACrack has been applied to generate K solutions for the three custom crack profiles suggested by EMC2 Results not yet available for the fourth profile, which was suggested by DEI 35 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
5 K Validation alpha=5, a/t=0.25, c=1.5 alpha=8, a/t=0.5, c=5 Proposed Crack Profiles alpha=2, a/t=0.8, c=7 4
Extra Case 3
2 1
0.9 0.8 alpha=8, a/t=5, c=5 alpha=2, a/t=0.8, c=7 0
0.7 alpha=5, a/t=0.25, c=1.5 Extra Case 0.6
-1 0.5 a/t 0.4
-2 0.3 0.2
-3 0.1 0
-4 0 1 2 3 4 5 6 7 8 Surface Crack length (inch)
-5 0 1 2 3 4 5 36 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
K Validation Corner Node Positions Along Crack Front 1.20 kver00-1: 2c/a=15.5, a/t=0.500 kver01-1: 2c/a=13.6, a/t=0.800 kver02-1: 2c/a=9.3, a/t=0.250 1.00 0.80 Crack Depth (in) 0.60 0.40 0.20 0.00 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Circumferential Distance Along ID (in) 37 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
K Validation K Result as Function of Relative Crack Front Position 35,000 kver00-1: 2c/a=15.5, a/t=0.500 30,000 kver01-1: 2c/a=13.6, a/t=0.800 kver02-1: 2c/a=9.3, a/t=0.250 FEA Stress Intensity Factor, K (psi-in )
0.5 25,000 20,000 15,000 10,000 5,000 0
1.0 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 0.0 Relative Distance Along Crack Front from Deepest Point to Surface Point (--)
38 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
K Validation K Result as Function of Circumferential Position on ID 35,000 kver00-1: 2c/a=15.5, a/t=0.500 kver01-1: 2c/a=13.6, a/t=0.800 kver02-1: 2c/a=9.3, a/t=0.250 30,000 FEA Stress Intensity Factor, K (psi-in )
0.5 25,000 20,000 15,000 10,000 5,000 0
0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Circumferential Distance Along ID (in) 39 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Model Convergence Summary Previous results presented by DEI on May 8 showed about 7.5 years to through-wall penetration for Phase 1 calculation geometry and loads
- Subsequent work shows increase in time from earlier results (~5.1 years) due mostly to slight change in WRS profile assumed Most recent comparisons between DEI and EMC2 results for Phase 1 calculation geometry and loads (including WRS) show close agreement in time to through-wall penetration
- DEI time to through-wall: 5.36 years
- EMC2 time to through-wall: 5.35 years Close agreement in independent models gives confidence that results are mathematically correct 40 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Model Convergence Summary (contd)
Time to through-wall observed to be sensitive to WRS assumption, but time from detectable leakage to rupture expected to be much less sensitive to WRS assumption
- Sensitivity of time to through-wall penetration with WRS due to importance of minimum in dependence of stress intensity factor at deepest point vs. crack depth
- Profile at time of through-wall penetration observed to be less sensitive to WRS Case to explicitly demonstrate convergence using refined growth steps still to be completed Additional work has been completed investigating effect of spatial mesh refinement on temperature strain simulation of WRS 41 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Update on Timeline of Activities WRS Modeling Validation Studies Leak-Rate Studies 42 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Leak Rate Calculations Approach PICEP and SQUIRT software models are being applied using crack morphology parameters appropriate to intergranular nature of PWSCC
- Wilkowski presentation at 2003 NRC Conference on Alloy 600 PWSCC in Gaithersburg, Maryland As a scoping tool, PICEP is being applied to calculate COD and leak rate as a function of assumed piping load
- See example on next slide For each FEA crack growth progression case, the leak rate as a function of time will be calculated on the basis of the COD directly from the through-wall portion of the complex crack FEA model
- The COD dependence through the wall thickness in the through-wall crack region will be examined to determine the controlling COD parameters 43 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Leak Rate Calculations Example Scoping Results for WC Relief Nozzle DM Weld 100.000 Full Moment (275 in-kips)
EPRI PICEP, Rev. 1 Half Moment Quarter Moment 10.000 Zero Moment SQUIRT (PWSCC) - Full Moment Leak Rate (gpm at 70°F) 1.000 0.100 PRELIMINARY 0.010 0.001 0 20 40 60 80 100 120 140 160 180 200 Total Crack Arc Length (deg) 44 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Status of NRC Confirmatory Research To be presented by NRC
- K Validation
- Model Convergence
- Update on Timeline of Activities
- WRS
- Phase II Sensitivity Studies
- Validation Studies
- Leak-Rate Studies 45 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Thursday Afternoon Agenda Presentation & Discussion of Proposed Sensitivity Matrix (Industry)
- List of Sensitivity Matrix Cases that Industry will Evaluate
- Loads/Geometries/WRS/CGR/Multiple Crack Growth 46 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Items Covered Item 1. Plant Specific Geometries Item 2. Plant Specific Loads Item 3. Proposed Weld Residual Stresses
- Cracks growing in an axisymmetric WRS field
- Cracks growing in an axisymmetric + repair WRS field Item 4. Crack Growth Rate Equation Item 5. Multiple Crack Growth Calculations Other Items
- Initial flaw geometry
- Redistribution of load given high WRS at ID surface
- Crack inserted directly into the 3-dimensional DEI WRS FEA model 47 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Specific Matrix Parameters Case #
- 1. Model type: Cylindrical model or crack inserted into nozzle-to-safe-end WRS FEA Model
- 2. Dimensions case: Config 1a, 1b, 2a, 2b, 3, 4, 5, 6, 7, 8, 9
- 3. Load assumption: Pm = x; Pb = y
- 4. Welding residual stress assumption (WRS): for example axisymmetric 1, 2, 3 or repair case 1, 2, 3 or elastic-plastic redistribution simulation
- 5. Crack growth rate equation exponent on K: n = 1.6, or for example 1.3, 2.0
- 6. Initial flaw aspect ratio assumption: 6:1 part-arc, 21:1 part arc, 360° full-arc
- 7. Initial flaw shape factor: semi-ellipse, near uniform depth (high shape factor),
low shape factor, or "natural" shape
- 8. Initial flaw depth: 26% or for example 10%, 40%
48 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Example Case Case YY:
- Cylindrical model;
- Config 1a dimensions;
- Pm = 3.5 ksi, Pb = 7.5 ksi;
- axisymmetric WRS1;
- CGR n = 1.6;
- 21:1 initial flaw;
- natural shape;
- 26% initial depth 49 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Selectively Vary Parameters
- 1. Model type: Cylindrical model in most cases; crack inserted into nozzle-to-safe-end WRS FEA Model as a check in a few cases
- 2. Dimensions case: cover all cases but may combine some cases within nozzle type (S&R, spray, and surge) if justified by runs showing small sensitivity
- 3. Load assumption: Cover full range of Pb for each dimension case; expect small sensitivity to range of Pm for each dimension case
- 4. Welding residual stress assumption (WRS): must check sensitivity to various cases
- 5. Crack growth rate equation exponent on K: use n = 1.6 for most cases; for cases showing smallest margin also use statistical lower and upper bounds for n from MRP-115 database
- 6. Initial flaw aspect ratio assumption: concentrate on 21:1 part-arc flaw and 360° full-arc flaws
- 7. Initial flaw shape factor: only a few cases to confirm insensitivity to this
- 8. Initial flaw depth: only a few cases to confirm insensitivity to this 50 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Final Case Matrix Exact combinations of parameters depends on
- Results from initial case runs
- FEA WRS results Applying the simplified axisymmetric growth model presented on May 8 to eliminate those combinations that result in arrest at a relatively shallow depth from consideration Input from May 31 and June 1 meeting discussions 51 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Outputs Time from detectable leakage to rupture
- Key parameter
- Assuming normal loads
- Assuming faulted loads for select cases Time from through-wall penetration to rupture
- Can be compared to time of most recent bare metal visual examination Total time from initial flaw to rupture
- Can be compared to operating age of each subject plant For some key cases, complete output parameters will be displayed in the report, as in the Phase 1 calculation 52 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Geometry and Load Combinations Loads Pm Pb Pb/(Pm+Pb)
Note: Pm in this table (ksi) (ksi) -
- of based on pressure Type Design nozzles Min Max Min Max Min Max stress pDo/4t. Pressure 1a 12 3.17 3.45 0.07 5.71 0.02 0.64 stress pDi2/(Do2-Di2) Safety 1b 4 3.20 3.71 0.78 5.74 0.20 0.63 plus deadweight and and Relief 2a 8 3.93 4.29 1.04 7.63 0.21 0.64 secondary piping axial Nozzles 2b 4 3.57 3.90 2.35 4.78 0.38 0.57 force and pressure on 3 7 3.16 3.24 0.00 6.70 0.00 0.67 crack face to be used 4 2 3.45 3.58 1.38 4.89 0.28 0.59 for crack growth. Spray 5 3 4.00 4.20 1.12 4.75 0.21 0.54 Nozzles 6 1 3.84 3.84 0.75 0.75 0.16 0.16 7 2 2.76 3.05 1.16 4.80 0.30 0.61 8 6 5.24 5.43 4.04 13.58 0.43 0.72 Surge Nozzles 9 2 4.92 5.06 6.65 14.55 0.57 0.74 53 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Initial Planned Matrix (slide 1/3)
Load Case CGR Initial Flaw Prelim Model Nozzle Expon. Shape Depth Case # Type Type Geometry Pm (ksi) Pb (ksi) Pb/(Pm+Pb) WRS Case n 2c/a Factor (%tw) 1 cylinder S&R Config 1a typical high high S&R no liner 1.6 21 or 360° natural 26% or 10%
2 cylinder S&R Config 1a typical above arrest above arrest S&R no liner 1.6 21 or 360° natural 26% or 10%
3 cylinder S&R Config 1b typical high high S&R no liner 1.6 21 or 360° natural 26% or 10%
4 cylinder S&R Config 1b typical above arrest above arrest S&R no liner 1.6 21 or 360° natural 26% or 10%
5 cylinder S&R Config 2a typical high high S&R with liner 1.6 21 or 360° natural 26% or 10%
6 cylinder S&R Config 2a typical above arrest above arrest S&R with liner 1.6 21 or 360° natural 26% or 10%
7 cylinder S&R Config 2b typical high high S&R with liner 1.6 21 or 360° natural 26% or 10%
8 cylinder S&R Config 2b typical above arrest above arrest S&R with liner 1.6 21 or 360° natural 26% or 10%
9 cylinder S&R Config 3 typical high high S&R no liner 1.6 21 or 360° natural 26% or 10%
10 cylinder S&R Config 3 typical above arrest above arrest S&R no liner 1.6 21 or 360° natural 26% or 10%
11 cylinder spray Config 4 typical high high generic spray 1.6 21 or 360° natural 26% or 10%
12 cylinder spray Config 4 typical above arrest above arrest generic spray 1.6 21 or 360° natural 26% or 10%
13 cylinder spray Config 5 typical high high generic spray 1.6 21 or 360° natural 26% or 10%
14 cylinder spray Config 5 typical above arrest above arrest generic spray 1.6 21 or 360° natural 26% or 10%
15 cylinder spray Config 6 typical high high generic spray 1.6 21 or 360° natural 26% or 10%
16 cylinder spray Config 6 typical above arrest above arrest generic spray 1.6 21 or 360° natural 26% or 10%
17 cylinder spray Config 7 typical high high generic spray 1.6 21 or 360° natural 26% or 10%
18 cylinder spray Config 7 typical above arrest above arrest generic spray 1.6 21 or 360° natural 26% or 10%
19 cylinder surge Config 8 typical high high surge with fill-in weld 1.6 21 or 360° natural 26% or 10%
20 cylinder surge Config 8 typical above arrest above arrest surge with fill-in weld 1.6 21 or 360° natural 26% or 10%
21 cylinder surge Config 9 typical high high surge no fill-in weld 1.6 21 or 360° natural 26% or 10%
22 cylinder surge Config 9 typical above arrest above arrest surge no fill-in weld 1.6 21 or 360° natural 26% or 10%
54 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Initial Planned Matrix (slide 2/3)
Load Case CGR Initial Flaw Prelim Model Nozzle Expon. Shape Depth Case # Type Type Geometry Pm (ksi) Pb (ksi) Pb/(Pm+Pb) WRS Case n 2c/a Factor (%tw) 23 cylinder S&R Config 1a typical high high S&R ID repair no liner 1.6 21 or 360° natural 26% or 10%
24 cylinder S&R Config 1a typical above arrest above arrest S&R ID repair no liner 1.6 21 or 360° natural 26% or 10%
25 cylinder S&R Config 2b typical high high S&R ID repair with liner 1.6 21 or 360° natural 26% or 10%
26 cylinder S&R Config 2b typical above arrest above arrest S&R ID repair with liner 1.6 21 or 360° natural 26% or 10%
27 cylinder surge Config 8 typical high high surge ID repair with fill-in 1.6 21 or 360° natural 26% or 10%
28 cylinder surge Config 8 typical above arrest above arrest surge ID repair with fill-in 1.6 21 or 360° natural 26% or 10%
29 cylinder bound bounding typical sens 1 sens 1 bounding 1.6 21 or 360° natural 26% or 10%
30 cylinder bound bounding typical sens 2 sens 2 bounding 1.6 21 or 360° natural 26% or 10%
31 cylinder bound bounding typical sens 3 sens 3 bounding 1.6 21 or 360° natural 26% or 10%
32 cylinder bound bounding typical sens 4 sens 4 bounding 1.6 21 or 360° natural 26% or 10%
33 cylinder S&R as-built 1 typical bounding bounding bounding 1.6 21 or 360° natural 26% or 10%
34 cylinder S&R as-built 2 typical bounding bounding bounding 1.6 21 or 360° natural 26% or 10%
35 cylinder S&R bounding S&R low bounding bounding bounding 1.6 21 or 360° natural 26% or 10%
36 cylinder S&R bounding S&R high bounding bounding bounding 1.6 21 or 360° natural 26% or 10%
37 cylinder TBD TBD typical bounding bounding effect of SS weld 1.6 21 or 360° natural 26% or 10%
38 cylinder S&R bounding S&R typical bounding bounding safe end ID buildup 1.6 21 or 360° natural 26% or 10%
39 cylinder S&R bounding S&R typical bounding bounding tweaked axisymmetric 1.6 21 or 360° natural 26% or 10%
40 cylinder S&R bounding S&R typical bounding bounding tweaked ID repair 1.6 21 or 360° natural 26% or 10%
41 cylinder spray bounding spray typical bounding bounding tweaked axisymmetric 1.6 21 or 360° natural 26% or 10%
42 cylinder surge bounding surge typical bounding bounding tweaked axisymmetric 1.6 21 or 360° natural 26% or 10%
43 cylinder surge bounding surge typical bounding bounding tweaked ID repair 1.6 21 or 360° natural 26% or 10%
55 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Initial Planned Matrix (slide 3/3)
Load Case CGR Initial Flaw Prelim Model Nozzle Expon. Shape Depth Case # Type Type Geometry Pm (ksi) Pb (ksi) Pb/(Pm+Pb) WRS Case n 2c/a Factor (%tw) 44 cylinder S&R bounding S&R typical bounding bounding shortened "weld" 1.6 21 or 360° natural 26% or 10%
45 cylinder S&R bounding S&R typical bounding bounding simulate e-p redistrib. 1.6 21 or 360° natural 26% or 10%
46 cylinder S&R bounding S&R typical bounding bounding bounding 1.6 2 natural 26%
47 cylinder S&R bounding S&R typical bounding bounding bounding 1.6 6 natural 26%
48 cylinder S&R bounding S&R typical bounding bounding bounding 1.6 21 low 26%
49 cylinder S&R bounding S&R typical bounding bounding bounding 1.6 21 semi-ellipse 26%
50 cylinder S&R bounding S&R typical bounding bounding bounding 1.6 21 high 26%
51 cylinder S&R bounding S&R typical bounding bounding bounding 1.6 21 natural 15%
52 cylinder S&R bounding S&R typical bounding bounding bounding 1.6 21 natural 40%
53 cylinder S&R bounding S&R typical bounding bounding bounding low 21 or 360° natural 26% or 10%
54 cylinder S&R bounding S&R typical bounding bounding bounding high 21 or 360° natural 26% or 10%
55 cylinder spray bounding spray typical bounding bounding bounding low 21 or 360° natural 26% or 10%
56 cylinder spray bounding spray typical bounding bounding bounding high 21 or 360° natural 26% or 10%
57 cylinder surge bounding surge typical bounding bounding bounding low 21 or 360° natural 26% or 10%
58 cylinder surge bounding surge typical bounding bounding bounding high 21 or 360° natural 26% or 10%
59 nozzle S&R bounding S&R typical bounding bounding axsymmetric 1.6 21 or 360° natural 26% or 10%
60 nozzle S&R bounding S&R typical bounding bounding ID repair case 1.6 21 or 360° natural 26% or 10%
61 nozzle surge bounding surge typical bounding bounding axsymmetric 1.6 21 or 360° natural 26% or 10%
62 nozzle surge bounding surge typical bounding bounding ID repair case 1.6 21 or 360° natural 26% or 10%
56 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Proposed Sensitivity Matrix Geometry and Load Inputs The following slides repeat the geometry and piping load information previously presented in order to support the sensitivity matrix discussions 57 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Nozzle Geometry for Subject Plants Summary There are a total of 51 pressurizer DM welds of concern in the group of nine plants:
- 35 safety and relief (S&R) nozzles (1 plant has only three S&R nozzles)
- 8 surge nozzles (+1 already overlayed)
- 8 spray nozzles (+1 examined by PDI process in 2005)
Using design drawings, basic weld dimensions have been tabulated for the 51 subject welds:
- Weld thickness
- For welds with taper from LAS nozzle to safe end, thickness is based on average of design diameters at toe on nozzle and at toe on safe end
- Liner or sleeve thickness not included in weld thickness for cases in which liner or sleeve is in direct contact with DM weld
- Radius to thickness ratio (Ri/t) based on design inside diameter at weld and weld thickness per previous bullet
- Approximate weld separation axial distance between root of DM weld and root of SS weld to piping 58 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Nozzle Geometry for Subject Plants Geometry Cases A review of design drawings for the nine plants indicates the following nozzle geometry cases:
- S&R nozzles
- Types 1a and 1b: W design without liner, connected to 6 pipe
- Types 2a and 2b: W design with liner directly covering DM weld, connected to 6 pipe
- Type 3: CE design (no liner), connected to 6 pipe
- Spray nozzles
- Type 4: W design with liner (does not extend to most of DM weld), connected to 4 pipe
- Type 5: W design with liner directly covering DM weld, connected to 4 pipe
- Type 6: W design without liner, connected to 6 pipe
- Surge nozzles
connected to 14 pipe
- Type 9: CE design (sleeve not extending to DM weld), connected to 12 pipe 59 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Nozzle Geometry and Repair History PRELIMINARY Summary Table Relief Safety A DM Weld Ri/t DM Weld Ri/t Butter Weld Butter Weld Piping NPS Piping NPS DM Weld t Weld Sep. OD Weld DM Weld t Weld Sep. OD Weld Design # Design #
Plant Code (in.) (in.) Repairs Repairs Repairs (in.) (in.) Repairs Repairs Repairs Plant A 1a 6" N 1.29 2.0 2.2 NR NR NR 1a 6" N 1.29 2.0 2.2 NR NR R4 Plant E 1a 6" N 1.29 2.0 2.2 NR NR R 1a 6" N 1.29 2.0 2.2 NR NR NR Plant H 1a 6" N 1.29 2.0 2.2 NR NR NR 1a 6" N 1.29 2.0 2.2 NR R R Plant B 2a 6" Y 1.07 2.6 2.6 NR NR R1 2a 6" Y 1.07 2.6 2.6 NR NR NR Plant G 2a 6" Y 1.07 2.6 2.6 NR NR NR 2a 6" Y 1.07 2.6 2.6 NR NR NR Plant C 2b 6" Y 1.07 2.6 2.3 NR NR NR 2b 6" Y 1.07 2.6 2.3 R Plant F 1b 6" N 1.41 1.8 3.3 NR NR NR 1b 6" N 1.41 1.8 3.3 R Plant D 3 6" N 1.41 1.8 6.8 NR NR NR 3 6" N 1.41 1.8 6.8 R NR NR Plant I 3 6" N 1.41 1.8 6.8 N/A N/A N/A 3 6" N 1.41 1.8 6.8 N/A N/A N/A Plant J 1a 6" N 1.29 2.0 2.2 Rx5 R1 R1 1a 6" N 1.29 2.0 2.2 R R2 NR Notes:
- 1. For Designs #2a, #2b, and #5, liner directly covers DM weld.
- 2. For Design #4, liner does not extend to most of DM weld.
- 6. NR = No weld repairs reported
- 7. Rn = Repairs reported (n indicates number of defect or repaired areas if reported; "x" indicates repeat weld repair operations)
- 8. N/A = Results for fabrication records review not available
- 9. Weld repair entries for Plants C and F are preliminary.
- 10. All pressurizer nozzle DM welds in Plant H are reported to be Alloy 82, not Alloy 82/182.
60 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Nozzle Geometry and Repair History PRELIMINARY Summary Table (contd)
Safety B Safety C DM Weld Ri/t DM Weld Ri/t Butter Weld Butter Weld Piping NPS Piping NPS DM Weld t Weld Sep. OD Weld DM Weld t Weld Sep. OD Weld Design # Design #
Plant Code (in.) (in.) Repairs Repairs Repairs (in.) (in.) Repairs Repairs Repairs Plant A 1a 6" N 1.29 2.0 2.2 NR R1 NR 1a 6" N 1.29 2.0 2.2 NR NR NR Plant E 1a 6" N 1.29 2.0 2.2 NR NR NR 1a 6" N 1.29 2.0 2.2 NR R NR Plant H 1a 6" N 1.29 2.0 2.2 NR NR NR 1a 6" N 1.29 2.0 2.2 NR NR NR Plant B 2a 6" Y 1.07 2.6 2.6 NR NR NR 2a 6" Y 1.07 2.6 2.6 NR NR NR Plant G 2a 6" Y 1.07 2.6 2.6 NR NR NR 2a 6" Y 1.07 2.6 2.6 NR NR NR Plant C 2b 6" Y 1.07 2.6 2.3 R 2b 6" Y 1.07 2.6 2.3 R Plant F 1b 6" N 1.41 1.8 3.3 NR NR NR 1b 6" N 1.41 1.8 3.3 NR NR NR Plant D 3 6" N 1.41 1.8 6.8 NR NR NR 3 6" N 1.41 1.8 6.8 NR NR NR Plant I 3 6" N 1.41 1.8 6.8 N/A N/A N/A No Safety C Plant J 1a 6" N 1.29 2.0 2.2 NR R6x2 NR 1a 6" N 1.29 2.0 2.2 NR NR NR Notes:
- 1. For Designs #2a, #2b, and #5, liner directly covers DM weld.
- 2. For Design #4, liner does not extend to most of DM weld.
- 6. NR = No weld repairs reported
- 7. Rn = Repairs reported (n indicates number of defect or repaired areas if reported; "x" indicates repeat weld repair operations)
- 8. N/A = Results for fabrication records review not available
- 9. Weld repair entries for Plants C and F are preliminary.
- 10. All pressurizer nozzle DM welds in Plant H are reported to be Alloy 82, not Alloy 82/182.
61 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Nozzle Geometry and Repair History PRELIMINARY Summary Table (contd)
Spray (all have thermal sleeve) Surge (all have thermal sleeve)
DM Weld Ri/t DM Weld Ri/t Butter Weld Butter Weld Piping NPS Piping NPS DM Weld t Weld Sep. OD Weld DM Weld t Weld Sep. OD Weld Design # Design #
Plant Code (in.) (in.) Repairs Repairs Repairs (in.) (in.) Repairs Repairs Repairs Plant A 4 4" Y 0.90 2.2 ~2.3 NR NR NR 8 14" N 1.58 3.8 3.4 NR R5 R3 Plant E 4 4" Y 0.90 2.2 ~2.3 R NR R 8 14" N 1.58 3.8 3.4 NR R3 NR Plant H Already PDI examined 8 14" N 1.58 3.8 3.4 NR NR NR Plant B 5 4" Y 0.78 2.7 2.2 NR NR NR 8 14" N 1.58 3.8 3.4 R1 R1x2 R2 Plant G 5 4" Y 0.78 2.7 2.2 NR NR NR 8 14" N 1.58 3.8 3.4 NR NR NR Plant C 5 4" Y 0.78 2.7 ~2.2 R 8 14" N 1.56 3.8 3.5 NR NR NR Plant F 6 6" N 1.15 2.5 3.6 NR NR NR Already structural overlayed Plant D 7 4" N 1.06 1.4 3.3 NR NR NR 9 12" N 1.47 3.4 3.0 NR NR NR Plant I 7 4" N 1.06 1.4 3.3 N/A N/A N/A 9 12" N 1.47 3.4 3.0 N/A N/A N/A Plant J 4 4" Y 0.90 2.2 ~2.3 R NR NR 8 14" N 1.58 3.8 3.4 R2 R1 NR Notes:
- 1. For Designs #2a, #2b, and #5, liner directly covers DM weld.
- 2. For Design #4, liner does not extend to most of DM weld.
- 6. NR = No weld repairs reported
- 7. Rn = Repairs reported (n indicates number of defect or repaired areas if reported; "x" indicates repeat weld repair operations)
- 8. N/A = Results for fabrication records review not available
- 9. Weld repair entries for Plants C and F are preliminary.
- 10. All pressurizer nozzle DM welds in Plant H are reported to be Alloy 82, not Alloy 82/182.
62 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
63 0 2 4 6 8 10 12 14 0.
01 A - Re (7.75x5.17) 00 0.
75 02 A - SA (7.75x5.17) 1.
50 03 A - SB (7.75x5.17) 2.
25 3.
00 04 A - SC (7.75x5.17) 3.
75 05 E - Re (7.75x5.17) 4.
50 5.
06 E - SA (7.75x5.17) 25 6.
00 07 E - SB (7.75x5.17) 6.
ID (in) 75 08 E - SC (7.75x5.17) 7.
OD (in) 50 8.
t (in) 25 09 H - Re (7.75x5.17) 9.
00 10 H - SA (7.75x5.17)
ID/t 9.
75 10 11 H - SB (7.75x5.17) .5 0
11
.2 12 H - SC (7.75x5.17) 5 12
.0 0
WC1 J - Re (7.75x5.17) 12
.7 5
13 WC1a J - Re/Sa (7.75x5.17) .5 0
14
.2 5
WC2 J - SA (7.75x5.17) 15
.0 0
WC3 J - SB (7.75x5.17) 15
.7 5
16
.5 WC4 J - SC (7.75x5.17) 0 17
.2 5
13 F - Re (8x5.19) 18
.0 0
18 14 F - SA (8x5.19) .7 5
19
.5 15 F - SB (8x5.19) 0 20
.2 5
16 F - SC (8x5.19) 21
.0 0
21
.7 17 B - Re (7.75x5.62) 5 Basic Weld Dimensions 22
.5 0
18 B - SA (7.75x5.62) 23
.2 5
24 19 B - SB (7.75x5.62) .0 0
24
.7 20 B - SC (7.75x5.62) 5 25
.5 0
21 G - Re (7.75x5.62) 26
.2 5
27 22 G - SA (7.75x5.62) .0 0
Project Review Meeting: Advanced FEA Crack Growth Evaluations 27
.7 5
23 G - SB (7.75x5.62) 28
.5 0
24 G - SC (7.75x5.62) 29
.2 5
30
.0 25 C - Re (7.75x5.62) 0 30
.7 5
26 C - SA (7.75x5.62) 31
.5 0
32 27 C - SB (7.75x5.62) .2 5
33
.0 0
28 C - SC (7.75x5.62) 33
.7 5
29 D - Re (8x5.19) 34
.5 0
35
.2 30 D - SA (8x5.19) 5 36
.0 0
31 D - SB (8x5.19) 36
.7 5
37 32 D - SC (8x5.19) .5 0
38
.2 33 I - Re (8x5.188) 5 39
.0 0
34 I - SA (8x5.188) 39
.7 5
40 35 I - SB (8x5.188) .5 0
41
.2 5
36 A - Sp (5.81x4.01) 42
.0 0
37 E - Sp (5.81x4.01) 42
.7 5
43
.5 WC5 J - Sp (5.81x4.01) 0 44
.2 5
38 B - Sp (5.81x4.25) 45
.0 0
45 39 G - Sp (5.81x4.25) .7 5
46
.5 0
40 C - Sp (5.81x4.25) 47
.2 5
41 F - Sp (8x5.695) 48
.0 0
48
.7 42 D - Sp (5.188x3.062) 5 49
.5 0
43 I - Sp (5.188x3.25) 50 Nozzle Geometry for Subject Plants
.2 5
May 31 and June 1, 2007, Reston, Virginia 51 44 A - Su (15x11.844) .0 0
51
.7 45 E - Su (15x11.844) 5 52
.5 0
46 H - Su (15x11.844) 53
.2 5
54 WC6 J - Su (15x11.844) .0 0
54
.7 5
47 B - Su (15x11.844) 55
.5 0
56 48 G - Su (15x11.844) .2 5
57
.0 49 C - Su (15x11.875) 0 57
.7 5
50 D - Su (13.063x10.125) 58
.5 0
59 51 I - Su (13.063x10.125) .2 5
60 0 50 .0 100 150 200 250 300 350 400 0
Plant-Specific Piping Loads Approach Design pipe loads have now been collected for each of the 51 subject welds Differences in pipe axial force and moment loads have multiple effects on the relative crack growth rate in the radial and circumferential directions, as well as an effect on critical crack size Therefore, cover full range of piping loads for 51 subject welds:
- All plants 2235 psig pressure
- Range of axial membrane stress loading, Pm
- Range of bending stress loading, Pb
- Range of ratio of bending to total stress loading, Pb/(Pm+Pb)
- Crack growth loads include dead weight and normal thermal pipe expansion loads (and normal thermal stratification loads in case of surge nozzles)
- Length of thermal strain applied to simulate WRS will be varied 64 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
65 Faxial (kips)
-15 -10 -5 0 5 10 15 20 25 30 35 40 0.
01 A - Re (7.75x5.17) 00 0.
75 02 A - SA (7.75x5.17) 1.
50 03 A - SB (7.75x5.17) 2.
25 3.
00 04 A - SC (7.75x5.17) 3.
75 05 E - Re (7.75x5.17) 4.
50 5.
06 E - SA (7.75x5.17) 25 6.
00 07 E - SB (7.75x5.17) 6.
75 08 E - SC (7.75x5.17) 7.
50 09 H - Re (7.75x5.17)
DW 8.
25 9.
00 10 H - SA (7.75x5.17) DW+SSE 9.
75 10 11 H - SB (7.75x5.17) .5 0
DW+T 11
.2 12 H - SC (7.75x5.17) 5 12
.0 DW+T+SSE 0 WC1 J - Re (7.75x5.17) 12
.7 5
13 WC1a J - Re/Sa (7.75x5.17) .5 DW+T+Strat 0 14
.2 5
WC2 J - SA (7.75x5.17) 15 DW+T+Strat+SSE .0 0
WC3 J - SB (7.75x5.17) 15
.7 5
16
.5 WC4 J - SC (7.75x5.17) 0 17
.2 5
13 F - Re (8x5.19) 18
.0 0
18 14 F - SA (8x5.19) .7 5
19
.5 15 F - SB (8x5.19) 0 20
.2 5
16 F - SC (8x5.19) 21
.0 0
21
.7 17 B - Re (7.75x5.62) 5 22
.5 0
18 B - SA (7.75x5.62) 23
.2 5
24 19 B - SB (7.75x5.62) .0 0
24
.7 20 B - SC (7.75x5.62) 5 25
.5 0
21 G - Re (7.75x5.62) 26
.2 Project Review Meeting: Advanced FEA Crack Growth Evaluations 5
27 22 G - SA (7.75x5.62) .0 0
27
.7 5
23 G - SB (7.75x5.62) 28
.5 0
24 G - SC (7.75x5.62) 29
.2 5
30
.0 25 C - Re (7.75x5.62) 0 30
.7 5
26 C - SA (7.75x5.62) 31
.5 0
32 27 C - SB (7.75x5.62) .2 5
33
.0 28 C - SC (7.75x5.62) 0 33
.7 5
29 D - Re (8x5.19) 34
.5 0
35
.2 30 D - SA (8x5.19) 5 36
.0 0
31 D - SB (8x5.19) 36
.7 5
Plant-Specific Piping Loads 37 32 D - SC (8x5.19) .5 0
38
.2 33 I - Re (8x5.188) 5 39
.0 0
34 I - SA (8x5.188) 39
.7 5
40 35 I - SB (8x5.188) .5 0
41
.2 5
36 A - Sp (5.81x4.01) 42
.0 0
37 E - Sp (5.81x4.01) 42
.7 5
43
.5 WC5 J - Sp (5.81x4.01) 0 44
.2 5
38 B - Sp (5.81x4.25) 45
.0 0
45 39 G - Sp (5.81x4.25) .7 5
46
.5 40 C - Sp (5.81x4.25) 0 47
.2 5
41 F - Sp (8x5.695) 48
.0 0
48
.7 42 D - Sp (5.188x3.062) 5 49
.5 0
43 I - Sp (5.188x3.25) 50
.2 May 31 and June 1, 2007, Reston, Virginia 5
51 44 A - Su (15x11.844) .0 0
51
.7 45 E - Su (15x11.844) 5 52
.5 0
46 H - Su (15x11.844) 53
.2 5
54 WC6 J - Su (15x11.844) .0 0
54
.7 5
47 B - Su (15x11.844) 55
.5 0
48 G - Su (15x11.844) 56
.2 5
57
.0 49 C - Su (15x11.875) 0 57
.7 5
50 D - Su (13.063x10.125) 58
.5 0
Nominal Axial Piping Loads (Not Including Endcap Pressure Load) 59 51 I - Su (13.063x10.125) .2 5
60 0 1 .0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0
66 Meff (in-kips) 0 1000 2000 3000 4000 5000 6000 0.
01 A - Re (7.75x5.17) 00 0.
75 02 A - SA (7.75x5.17) 1.
50 03 A - SB (7.75x5.17) 2.
25 3.
00 04 A - SC (7.75x5.17) 3.
75 05 E - Re (7.75x5.17) 4.
50 5.
06 E - SA (7.75x5.17) 25 P+DW 6.
00 07 E - SB (7.75x5.17) 6.
75 08 E - SC (7.75x5.17) P+DW+SSE 7.
50 8.
25 09 H - Re (7.75x5.17) 9.
P+DW+T 00 10 H - SA (7.75x5.17) 9.
75 10 11 H - SB (7.75x5.17) P+DW+T+SSE .5 0
11
.2 12 H - SC (7.75x5.17) 5 12
.0 P+DW+T+Strat 0 WC1 J - Re (7.75x5.17) 12
.7 5
13 WC1a J - Re/Sa (7.75x5.17) .5 0
P+DW+T+Strat+SSE 14
.2 5
WC2 J - SA (7.75x5.17) 15
.0 0
WC3 J - SB (7.75x5.17) 15
.7 5
16
.5 WC4 J - SC (7.75x5.17) 0 17
.2 5
13 F - Re (8x5.19) 18
.0 0
18 14 F - SA (8x5.19) .7 5
19
.5 15 F - SB (8x5.19) 0 20
.2 5
16 F - SC (8x5.19) 21
.0 0
21
.7 17 B - Re (7.75x5.62) 5 22
.5 0
18 B - SA (7.75x5.62) 23
.2 5
24 19 B - SB (7.75x5.62) .0 0
24
.7 20 B - SC (7.75x5.62) 5 25
.5 0
Project Review Meeting: Advanced FEA Crack Growth Evaluations 21 G - Re (7.75x5.62) 26
.2 5
27 22 G - SA (7.75x5.62) .0 0
27
.7 5
23 G - SB (7.75x5.62) 28
.5 0
24 G - SC (7.75x5.62) 29
.2 5
30
.0 25 C - Re (7.75x5.62) 0 30
.7 5
26 C - SA (7.75x5.62) 31
.5 0
32 27 C - SB (7.75x5.62) .2 5
33
.0 28 C - SC (7.75x5.62) 0 33
.7 5
29 D - Re (8x5.19) 34
.5 0
35 30 D - SA (8x5.19) .2 5
36
.0 0
31 D - SB (8x5.19) 36
.7 5
Plant-Specific Piping Loads 37 32 D - SC (8x5.19) .5 0
38
.2 33 I - Re (8x5.188) 5 39
.0 0
34 I - SA (8x5.188) 39
.7 5
40 35 I - SB (8x5.188) .5 0
41
.2 5
36 A - Sp (5.81x4.01) 42
.0 0
37 E - Sp (5.81x4.01) 42
.7 5
43
.5 WC5 J - Sp (5.81x4.01) 0 44
.2 5
38 B - Sp (5.81x4.25) 45
.0 0
45 39 G - Sp (5.81x4.25) .7 5
46
.5 40 C - Sp (5.81x4.25) 0 47
.2 5
41 F - Sp (8x5.695) 48
.0 0
48
.7 42 D - Sp (5.188x3.062) 5 49
.5 0
43 I - Sp (5.188x3.25) 50
.2 5
May 31 and June 1, 2007, Reston, Virginia 51 44 A - Su (15x11.844) .0 0
51
.7 45 E - Su (15x11.844) 5 52
.5 0
46 H - Su (15x11.844) 53
.2 5
54 WC6 J - Su (15x11.844) .0 0
54
.7 5
47 B - Su (15x11.844)
Nominal Effective Bending Moment Load (Full Scale) 55
.5 0
48 G - Su (15x11.844) 56
.2 5
57
.0 49 C - Su (15x11.875) 0 57
.7 5
50 D - Su (13.063x10.125) 58
.5 0
59 51 I - Su (13.063x10.125) .2 5
60 0 1 .0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0
67 Meff (in-kips) 0 100 200 300 400 500 600 700 800 0.
01 A - Re (7.75x5.17) 00 0.
75 02 A - SA (7.75x5.17) 1.
50 03 A - SB (7.75x5.17) 2.
25 3.
00 04 A - SC (7.75x5.17) 3.
75 05 E - Re (7.75x5.17) 4.
50 5.
06 E - SA (7.75x5.17) 25 P+DW 6.
00 07 E - SB (7.75x5.17) 6.
75 08 E - SC (7.75x5.17) P+DW+SSE 7.
50 8.
25 09 H - Re (7.75x5.17)
P+DW+T 9.
00 10 H - SA (7.75x5.17) 9.
75 10 11 H - SB (7.75x5.17) P+DW+T+SSE .5 0
11
.2 12 H - SC (7.75x5.17) 5 12
.0 P+DW+T+Strat 0 WC1 J - Re (7.75x5.17) 12
.7 5
13 WC1a J - Re/Sa (7.75x5.17) .5 P+DW+T+Strat+SSE 0 14
.2 5
WC2 J - SA (7.75x5.17) 15
.0 0
WC3 J - SB (7.75x5.17) 15
.7 5
16
.5 WC4 J - SC (7.75x5.17) 0 17
.2 5
13 F - Re (8x5.19) 18
.0 0
18 14 F - SA (8x5.19) .7 5
19
.5 15 F - SB (8x5.19) 0 20
.2 5
16 F - SC (8x5.19) 21
.0 0
21 17 B - Re (7.75x5.62) .7 5
22
.5 0
18 B - SA (7.75x5.62) 23
.2 5
24 19 B - SB (7.75x5.62) .0 0
24
.7 20 B - SC (7.75x5.62) 5 25
.5 0
21 G - Re (7.75x5.62)
Project Review Meeting: Advanced FEA Crack Growth Evaluations 26
.2 5
27 22 G - SA (7.75x5.62) .0 0
27
.7 5
23 G - SB (7.75x5.62) 28
.5 0
24 G - SC (7.75x5.62) 29
.2 5
30
.0 25 C - Re (7.75x5.62) 0 30
.7 5
26 C - SA (7.75x5.62) 31
.5 0
32 27 C - SB (7.75x5.62) .2 5
33
.0 28 C - SC (7.75x5.62) 0 33
.7 5
29 D - Re (8x5.19) 34
.5 0
35
.2 30 D - SA (8x5.19) 5 36
.0 0
31 D - SB (8x5.19) 36
.7 5
Plant-Specific Piping Loads 37 32 D - SC (8x5.19) .5 0
38
.2 33 I - Re (8x5.188) 5 39
.0 0
34 I - SA (8x5.188) 39
.7 5
40 35 I - SB (8x5.188) .5 0
41
.2 5
36 A - Sp (5.81x4.01) 42
.0 0
37 E - Sp (5.81x4.01) 42
.7 5
43
.5 WC5 J - Sp (5.81x4.01) 0 44
.2 5
38 B - Sp (5.81x4.25) 45
.0 0
45 39 G - Sp (5.81x4.25) .7 5
46
.5 40 C - Sp (5.81x4.25) 0 47
.2 5
41 F - Sp (8x5.695) 48
.0 0
48
.7 42 D - Sp (5.188x3.062) 5 49
.5 0
43 I - Sp (5.188x3.25) 50
.2 May 31 and June 1, 2007, Reston, Virginia 5
51 44 A - Su (15x11.844) .0 0
51
.7 45 E - Su (15x11.844) 5 52
.5 0
46 H - Su (15x11.844) 53
.2 5
54 WC6 J - Su (15x11.844) .0 0
54
.7 5
47 B - Su (15x11.844) 55
.5 0
56 48 G - Su (15x11.844) .2 5
57
.0 49 C - Su (15x11.875) 0 57
.7 5
50 D - Su (13.063x10.125) 58 Nominal Effective Bending Moment Load (Partial Scale)
.5 0
59 51 I - Su (13.063x10.125) .2 5
60 0 1 .0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0
68 Pm , Pb , Pm +Pb Stress Loading (ksi) 0 4 8 12 16 0.0 01 A - Re (7.75x5.17) 0 0.7 5
02 A - SA (7.75x5.17) 1.5 0
2.2 03 A - SB (7.75x5.17) 5 3.0 0
04 A - SC (7.75x5.17) 3.7 5
05 E - Re (7.75x5.17) 4.5 0
5.2 06 E - SA (7.75x5.17) 5 6.0 0
07 E - SB (7.75x5.17) Pm 6.7 5
08 E - SC (7.75x5.17) 7.5 0
Pm with SSE 8.2 09 H - Re (7.75x5.17) 5 9.0 Pb 0 10 H - SA (7.75x5.17) 9.7 5
Pb with SSE 10 11 H - SB (7.75x5.17) .5 0
11
.2 5
12 H - SC (7.75x5.17) Pm+Pb 12
.0 0
WC1 J - Re (7.75x5.17) 12
.7 Pm+Pb with SSE 5 13
.5 WC1a J - Re/Sa (7.75x5.17) 0 14
.2 5
WC2 J - SA (7.75x5.17) 15
.0 0
15 WC3 J - SB (7.75x5.17) .7 5
16
.5 WC4 J - SC (7.75x5.17) 0 17
.2 5
13 F - Re (8x5.19) 18
.0 0
18 14 F - SA (8x5.19) .7 5
19
.5 0
15 F - SB (8x5.19) 20
.2 5
16 F - SC (8x5.19) 21
.0 0
21
.7 17 B - Re (7.75x5.62) 5 22
.5 0
18 B - SA (7.75x5.62) 23
.2 5
24 19 B - SB (7.75x5.62) .0 0
24
.7 5
20 B - SC (7.75x5.62) 25
.5 0
21 G - Re (7.75x5.62) 26
.2 5
Project Review Meeting: Advanced FEA Crack Growth Evaluations 27
.0 22 G - SA (7.75x5.62) 0 ASME Code Nominal Stress Loading for Pressure and 27
.7 5
23 G - SB (7.75x5.62) 28
.5 0
29 24 G - SC (7.75x5.62) .2 5
30
.0 25 C - Re (7.75x5.62) 0 30
.7 5
26 C - SA (7.75x5.62) 31
.5 0
32
.2 27 C - SB (7.75x5.62) 5 33
.0 0
28 C - SC (7.75x5.62) 33
.7 5
29 D - Re (8x5.19) 34
.5 0
35
.2 30 D - SA (8x5.19) 5 36
.0 0
31 D - SB (8x5.19) 36
.7 5
37 32 D - SC (8x5.19) .5 0
Plant-Specific Piping Loads 38
.2 5
33 I - Re (8x5.188) 39
.0 0
34 I - SA (8x5.188) 39
.7 5
40
.5 35 I - SB (8x5.188) 0 41
.2 5
36 A - Sp (5.81x4.01) 42
.0 0
42 37 E - Sp (5.81x4.01) .7 5
43
.5 WC5 J - Sp (5.81x4.01) 0 44
.2 5
38 B - Sp (5.81x4.25) 45
.0 0
45
.7 39 G - Sp (5.81x4.25) 5 46
.5 0
40 C - Sp (5.81x4.25) 47
.2 5
41 F - Sp (8x5.695) 48
.0 0
48
.7 42 D - Sp (5.188x3.062) 5 49
.5 0
43 I - Sp (5.188x3.25) 50
.2 5
May 31 and June 1, 2007, Reston, Virginia 51 44 A - Su (15x11.844) .0 0
51
.7 5
45 E - Su (15x11.844) 52
.5 0
46 H - Su (15x11.844) 53
.2 5
54
.0 WC6 J - Su (15x11.844) 0 54
.7 5
47 B - Su (15x11.844) 55
.5 0
56 48 G - Su (15x11.844) .2 5
57
.0 0
Dead Weight Loading 49 C - Su (15x11.875) 57
.7 5
50 D - Su (13.063x10.125) 58
.5 0
59
.2 51 I - Su (13.063x10.125) 5 60 0 1 .0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0
69 Pm , Pb , Pm +Pb Stress Loading (ksi) 0 5 10 15 20 0.0 01 A - Re (7.75x5.17) 0 0.7 5
02 A - SA (7.75x5.17) 1.5 0
2.2 03 A - SB (7.75x5.17) 5 3.0 0
04 A - SC (7.75x5.17) 3.7 5
05 E - Re (7.75x5.17) 4.5 0
5.2 06 E - SA (7.75x5.17) 5 6.0 Pm 0 07 E - SB (7.75x5.17) 6.7 5
08 E - SC (7.75x5.17) 7.5 Pm with SSE 0 8.2 09 H - Re (7.75x5.17) 5 Pb 9.0 0
10 H - SA (7.75x5.17) 9.7 5
11 H - SB (7.75x5.17)
Pb with SSE 10
.5 0
11
.2 Pm+Pb 5 12 H - SC (7.75x5.17) 12
.0 0
WC1 J - Re (7.75x5.17) 12 Pm+Pb with SSE .7 5
13
.5 WC1a J - Re/Sa (7.75x5.17) 0 14
.2 5
WC2 J - SA (7.75x5.17) 15
.0 0
15 WC3 J - SB (7.75x5.17) .7 5
16
.5 WC4 J - SC (7.75x5.17) 0 17
.2 5
13 F - Re (8x5.19) 18
.0 0
18 14 F - SA (8x5.19) .7 5
19
.5 0
15 F - SB (8x5.19) 20
.2 5
16 F - SC (8x5.19) 21
.0 0
21
.7 17 B - Re (7.75x5.62) 5 22
.5 0
18 B - SA (7.75x5.62) 23
.2 5
24 19 B - SB (7.75x5.62) .0 0
24
.7 5
20 B - SC (7.75x5.62) 25
.5 0
21 G - Re (7.75x5.62) 26
.2 5
Project Review Meeting: Advanced FEA Crack Growth Evaluations 27
.0 22 G - SA (7.75x5.62) 0 27
.7 5
23 G - SB (7.75x5.62) 28
.5 ASME Code Nominal Stress Loading for Pressure, Dead 0
29 24 G - SC (7.75x5.62) .2 5
30
.0 25 C - Re (7.75x5.62) 0 30
.7 5
26 C - SA (7.75x5.62) 31
.5 0
32
.2 27 C - SB (7.75x5.62) 5 33
.0 0
28 C - SC (7.75x5.62) 33
.7 5
29 D - Re (8x5.19) 34
.5 0
35
.2 30 D - SA (8x5.19) 5 36
.0 0
31 D - SB (8x5.19) 36
.7 5
37 32 D - SC (8x5.19) .5 0
Plant-Specific Piping Loads 38
.2 5
33 I - Re (8x5.188) 39
.0 0
34 I - SA (8x5.188) 39
.7 5
40
.5 35 I - SB (8x5.188) 0 41
.2 5
36 A - Sp (5.81x4.01) 42
.0 0
42 37 E - Sp (5.81x4.01) .7 5
43
.5 WC5 J - Sp (5.81x4.01) 0 44
.2 5
38 B - Sp (5.81x4.25) 45
.0 0
45
.7 39 G - Sp (5.81x4.25) 5 46
.5 0
40 C - Sp (5.81x4.25) 47
.2 5
41 F - Sp (8x5.695) 48
.0 0
48
.7 42 D - Sp (5.188x3.062) 5 49
.5 0
43 I - Sp (5.188x3.25) 50
.2 5
May 31 and June 1, 2007, Reston, Virginia 51 44 A - Su (15x11.844) .0 0
51
.7 5
45 E - Su (15x11.844) 52
.5 0
46 H - Su (15x11.844) 53
.2 5
54
.0 WC6 J - Su (15x11.844) 0 54
.7 5
47 B - Su (15x11.844) 55
.5 0
56 48 G - Su (15x11.844) .2 5
57
.0 49 C - Su (15x11.875) 0 57
.7 5
50 D - Su (13.063x10.125) 58
.5 0
59
.2 51 I - Su (13.063x10.125) 5 Weight, and Normal Thermal Loading 60 0 1 .0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0
70 Pm , Pb , Pm +Pb Stress Loading (ksi) 0 5 10 15 20 25 30 35 40 0.
01 A - Re (7.75x5.17) 00 0.
75 02 A - SA (7.75x5.17) 1.
50 03 A - SB (7.75x5.17) 2.
25 3.
00 04 A - SC (7.75x5.17) 3.
75 05 E - Re (7.75x5.17) 4.
50 5.
06 E - SA (7.75x5.17) 25 Pm 6.
00 07 E - SB (7.75x5.17) 6.
75 08 E - SC (7.75x5.17)
Pm with SSE 7.
50 8.
Pb 25 09 H - Re (7.75x5.17) 9.
00 10 H - SA (7.75x5.17) Pb with SSE 9.
75 10 11 H - SB (7.75x5.17) .5 0
Pm+Pb 11
.2 5
12 H - SC (7.75x5.17) 12
.0 Pm+Pb with SSE 0 WC1 J - Re (7.75x5.17) 12
.7 5
13 WC1a J - Re/Sa (7.75x5.17) .5 0
14
.2 5
WC2 J - SA (7.75x5.17) 15
.0 0
WC3 J - SB (7.75x5.17) 15
.7 5
16
.5 WC4 J - SC (7.75x5.17) 0 17
.2 5
13 F - Re (8x5.19) 18
.0 0
18 14 F - SA (8x5.19) .7 5
19
.5 15 F - SB (8x5.19) 0 20
.2 5
16 F - SC (8x5.19) 21
.0 0
21
.7 17 B - Re (7.75x5.62) 5 22
.5 0
18 B - SA (7.75x5.62) 23
.2 5
24 19 B - SB (7.75x5.62) .0 0
24
.7 20 B - SC (7.75x5.62) 5 25
.5 0
21 G - Re (7.75x5.62) 26
.2 5
Project Review Meeting: Advanced FEA Crack Growth Evaluations 27 22 G - SA (7.75x5.62) .0 0
27
.7 5
23 G - SB (7.75x5.62) 28
.5 0
24 G - SC (7.75x5.62) 29
.2 5
30
.0 25 C - Re (7.75x5.62) 0 30
.7 ASME Nominal Stress Loading for Pressure, Dead Weight, 5
26 C - SA (7.75x5.62) 31
.5 0
32 27 C - SB (7.75x5.62) .2 5
33
.0 28 C - SC (7.75x5.62) 0 33
.7 5
29 D - Re (8x5.19) 34
.5 0
35
.2 30 D - SA (8x5.19) 5 36
.0 0
31 D - SB (8x5.19) 36
.7 5
37 32 D - SC (8x5.19) .5 0
Plant-Specific Piping Loads 38
.2 33 I - Re (8x5.188) 5 39
.0 0
34 I - SA (8x5.188) 39
.7 5
40 35 I - SB (8x5.188) .5 0
41
.2 5
36 A - Sp (5.81x4.01) 42
.0 0
37 E - Sp (5.81x4.01) 42
.7 5
43
.5 WC5 J - Sp (5.81x4.01) 0 44
.2 5
38 B - Sp (5.81x4.25) 45
.0 0
45 39 G - Sp (5.81x4.25) .7 5
46
.5 40 C - Sp (5.81x4.25) 0 47
.2 5
41 F - Sp (8x5.695) 48
.0 0
48
.7 42 D - Sp (5.188x3.062) 5 49
.5 0
43 I - Sp (5.188x3.25) 50
.2 5
51 44 A - Su (15x11.844) .0 0
May 31 and June 1, 2007, Reston, Virginia 51
.7 45 E - Su (15x11.844) 5 52
.5 0
46 H - Su (15x11.844) 53
.2 5
54 WC6 J - Su (15x11.844) .0 0
54
.7 5
47 B - Su (15x11.844) 55
.5 0
48 G - Su (15x11.844) 56
.2 5
57
.0 49 C - Su (15x11.875) 0 57
.7 5
50 D - Su (13.063x10.125) 58
.5 0
59 51 I - Su (13.063x10.125) .2 5
60 0 1 .0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 0 Normal Thermal, and Normal Thermal Stratification Loading
Friday Agenda Discussion of Proposed Sensitivity Matrix (Industry & NRC)
Proposed Acceptance Criteria and Safety Factors (Industry)
Plans for next meeting(s) (Industry & NRC)
Meeting Summary and Conclusions (Industry & NRC) 71 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Discussion of Proposed Sensitivity Matrix Review of Thursday Discussions 72 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors Topics
Background
- NRC comment in March 5 letter
- LBB assessments (NUREG-0800 SRP 3.6.3, etc.)
SF considerations for subject evaluations
- Short-term implementation issues
- Efforts addressing uncertainties
- Modeling conservatisms
- Operating ages of subject plants Conclusions
- Summary
- Acceptance criteria under development 73 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors NRC Comment in March 5 Letter Safety Factor. The prior industry and NRC staff fracture mechanics analyses did not consider safety factors in their crack stability analyses. The American Society of Mechanical Engineers Boiler and Pressure Vessel Code requires the use of a safety factor of 3 to the applied stress intensity factor to determine crack stability under normal load conditions for a deterministic analysis. The safety factor is required even for a bounding analysis because there are uncertainties with all the input variables, and there are some things that are not accounted for in the deterministic analyses. Industry should consider the use of a safety factor to cover uncertainties in these analyses including the estimation of leakage.
74 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors ASME Section XI ASME Section XI uses a safety factor on load for crack stability in evaluations for continued service of actual detected cracks
- Recent code versions use factor of 2.7 for normal loads (Service Level A)
- Previous code versions use factor of 3.0 for normal loads
- Reduced factors are listed for infrequent loads (Service Levels B, C, and D)
Such Section XI evaluations do not customarily include extensive sensitivity studies of calculation input parameters 75 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors LBB Evaluations (NUREG-0800 SRP 3.6.3, etc.)
For regulatory LBB assessments, SFs are traditionally applied to the detection leak rate and through-wall critical crack length
- SF of 10 on detection leak rate
- SF of 2.0 on through-wall critical crack length
- SF of 1.4 on load for crack stability Such LBB assessments do not customarily include extensive sensitivity studies of calculation input parameters Such LBB assessments are intended to cover operation through end of licensing period 76 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors Short-term Implementation Issue The question at hand is whether detailed crack growth, leak rate, and crack stability calculations demonstrate sufficiently high assurance of detection of leakage prior to rupture to support orderly timing of mitigation or first PDI examination at soonest refueling outage opportunity
- 2 to 5 months after preferred implementation date of 12/31/2007 This type of short-term implementation issue is different than
- long-term assessments such as regulatory LBB
- evaluations of actual detected flaws for continued operation 77 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors Efforts Addressing Uncertainties The current effort is explicitly addressing various modeling uncertainties in a robust manner in order to reduce analysis uncertainties:
- Explicit consideration of dimensions and loads for each subject weld
- Inclusion of piping torsion load as part of crack growth driver
- Effect of as-built dimensions vs. design dimensions
- Sensitivity to various assumed welding residual stress profiles
- Welding residual stress distributions based on weld repair data collected for subject welds
- Potential effect of SS weld on stresses in DM weld
- Effect of adjacent minor welds such as sleeve fill-in weld and liner fillet weld
- Effect of uncertainty in crack growth rate equation K exponent
- Effect of uncertainty in crack growth rate power-law constant
- Consideration of initial cracks with high length-to-depth aspect ratios and initial 360° full-arc cracks 78 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors Efforts Addressing Uncertainties (contd)
- Effect of uncertainty in initial flaw shape
- Sensitivity cases including detailed geometry and Q-stress load not usually considered
- Explicit consideration of non-leaking (i.e., surface) portion of crack in crack stability calculations
- Use of crack stability model for arbitrary crack shape rather than for idealized crack geometries
- NSC calculations based on flow strength of safe end material (assumes crack located near safe end, unlike apparent locations of WC indications and expected plane of maximum welding residual stress)
- Flow stress based on average of yield and ultimate strengths
- Detailed consideration of applicability of EPFM failure mode
- Detailed consideration of appropriate treatment of secondary stresses
- Consideration of potential effect of local ligament collapse
- Leak rate calculations using two standard industry codes
- Leak rate calculations based on COD from FEA rather than standard COD expressions for simplified loading assumption
- Verification and validation activities 79 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors Modeling Conservatisms Other modeling simplifications have been made, so no credit is conservatively taken for:
- Tendency for finger-like crack growth in weld metal materials in through-wall direction
- Tendency for crack initiation to be associated with weld repairs, which tend to drive cracks through-wall
- Likely beneficial effect of weld start-stops on WRS field
- 15 of 51 subject welds having liners (which are intended to keep material under the liner sealed from primary fluid) that cover the DM weld
- Cracking through thickness of the liner fillet weld may be required prior to initiation of cracking in main DM weld
- Likely temperature of spray nozzle DM welds significantly below pressurizer saturation temperature due to cooling from normal continuous flow in spray line
- Possible nonzero stress intensity factor threshold for growth
- Lower crack growth rate for growth perpendicular to dendrite solidification direction (best-estimate factor of 2.0 from MRP-115) 80 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors Operating Ages of Subject Plants Operating age is a measure of effective degradation time
- All subject pressurizers and Wolf Creek operate at the same nominal pressure and temperature Wolf Creek accumulated 150,000 operating hours to February 1, 2006 Eight of nine subject plants have lower operating age to 2/1/2006 compared to Wolf Creek:
- 95,000 hrs
- 96,000 hrs
- 118,000 hrs
- 119,000 hrs
- 129,000 hrs
- 140,000 hrs
- 142,000 hrs
- 147,000 hrs
- 154,000 hrs 81 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors Conclusions - Summary It is appropriate that analyses demonstrate a high and sufficient level of assurance given possibility of circumferential flaws This short-term implementation issue is different than long-term safety evaluations or disposition of actual detected growing flaws Extensive consideration of analysis uncertainties and modeling conservatisms reduce the effect of analysis uncertainties Operating ages of subject plants are generally less than that for Wolf Creek
- This effect tends to lower probability of crack initiation in subject plants
- However, time for crack initiation not explicitly credited in the type of leakage prior to rupture calculation being performed 82 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Acceptance Criteria and Safety Factors Conclusions - Acceptance Criteria Under Development Acceptance criteria are currently under development for this project:
- Calculated time between leak detection and critical crack is main assessment parameter
- There is a high confidence of leak detection and plant shutdown within 7 days after the leak rate reaches 0.25 gpm
- A margin factor >1 on the calculated leak rate is under consideration to address the uncertainty in the best-estimate leak rate predicted by the leak rate codes
- Given extensive consideration of analysis uncertainties and modeling conservatisms, a margin factor of 1 on critical crack size may be appropriate
- A secondary assessment parameter is the time between the initial crack and the critical crack, which can be compared to the operating age of each subject weld 83 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Plans for Next Meeting(s)
Previously tentatively scheduled meeting:
- June 19 meeting: Present Phase II results Evening of Monday, June 11 is a potential opportunity for meeting around the EPRI Alloy 600 conference in Atlanta 84 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Meeting Summary and Conclusions Industry NRC 85 Project Review Meeting: Advanced FEA Crack Growth Evaluations May 31 and June 1, 2007, Reston, Virginia
Westinghouse and CE Pressurizer Nozzle Fabrication Detail Warren Bamford & Cameron Martin Wolf Creek Task Group Meeting May 31 - June 1, 2007 1
Westinghouse Design Pressurizer 2
Welding Process for Pressurizer Nozzles All welds are U-groove design; land is 0.060 thick minimum Weld preps on buttering and safe end are abutted, and clamped in place Three initial passes are made: TIG PT of the initial pass Remainder of weld is completed, OD welding, MIG 3
Welding Process for Pressurizer Nozzles (contd.)
Weld ID is ground until any boundary between the two sides disappears (max. depth ~0.7 inches)
PT applied to verify sound weld ID is then re-welded, then PT of ID and OD No further welding performed, unless repairs are required as a result of RT ID welding is small compared to the overall thickness Finite element modeling reflects this process 4
Westinghouse Design: Weld Detail (Example: Safe End to Surge Nozzle) 5
Westinghouse Design: Nozzle Buttering Detail (Surge Nozzle Example) 6
Westinghouse Design: Weld Detail (Example: Upper Head Safe End to Nozzle)
Weld and Back Chip 7
Westinghouse Design: Buttering Detail (Example: Upper Head Nozzle) 8
Westinghouse Design: Fabrication Time Line (Example: Surge Nozzle)
Example Surge Nozzle Fabrication Time Line Weld Weld Area Order Description Weld Material NDE 2 PT (All Nozzle 4 Alloy 82/182 1 Nozzle Cladding Stainless Steel Clad) Buttering Alloy 82/182 7 PT (B/PWHT) Weld Stainless Steel Stainless Steel RT (B/PWHT and 1 Weld Pipe 2 Nozzle Buttering Alloy 82 A/PWHT) Stainless Steel PT surface prior Clad Buttering to to Weld 3 Cladding Tie-in Alloy 182 PT- After Weld 1st 3 passes - Alloy 82 Safe-End to Fill in - Alloy 182 PT and RT Thermal Stainless Steel 4 Nozzle (Included Back Chip) Sleeve Butter to Safe End Thermal Sleeve Clad Tie-In 5 Fill-in Weld Alloy 82 PT Fill-in Thermal 3
Weld Sleeve Weld Thermal Sleeve to 6 Safe-End Alloy 82 PT 5 6 7 Pipe to Safe End Field Weld 9
Combustion Engineering Pressurizer 10
Welding Process for CE Pressurizer Nozzles All welds are U-groove design; land is 0.090 thick minimum Weld preps on buttering and safe end are abutted, and clamped in place Welding process similar to the W process, but ID is purposely undersized on the diameter 11
Welding Process for Pressurizer Nozzles (contd.)
Pipe ID is machined to the proper diameter, thus cleaning up the root pass of the weld PT of ID applied to verify sound weld PT of OD, and RT performed No further welding performed, unless repairs are required No ID welding 12
Machining Requirements for CE Designs (Surge Nozzle Example) 13
CE Design: Nozzle Buttering Detail (Example: Surge Nozzle) 14
Progress Report on Secondary Stress Study Ted L. Anderson, Ph.D., P.E.
May 31, 2007
Overview
Elastic and elastic-plastic finite element analysis to determine the effect of an imposed end rotation on bending moment and crack driving force.
- Total pipe length (2L) = 60 in & 60 ft (L corresponds to the length of the model due to symmetry conditions).
- Initial (uncracked) bending stress = 30 ksi (analyses for 10 & 20 ksi currently in progress).
- Through-wall cracks of various lengths.
Moment knock-down factor (M/Mo) for a fixed rotation ():
- Ratio of the bending moment of the cracked pipe to that of the uncracked pipe.
Modified R-O to Avoid Yielding below 30 ksi 90 80 70 60 True Stress, ksi 50 Ramberg-Osgood 40 Assumed for FEA 30 20 10 0
0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 True Plastic Strain
Unexpected Results
For an imposed rotation and very long circumferential through-wall cracks, partial closure was observed.
Closure was not observed when a moment was imposed.
The 3D cracked pipe does not behave according to simple beam theory.
posed Moment on Cracked Pipe M
posed Rotation on Cracked Pipe closure Center of Rotaton
Imposed Rotation mpressive resses on rack Plane Crack Tip
Imposed Moment Crack Tip
Elastic Analysis Elastic Analysis, Imposed Rotation 1.00 0.95
- Crack Closure 0.90 0.85 0.80 M/Mo L = 30 in 0.75 L = 30 ft 0.70 0.65 0.60 0.55 0.50 0 0.2 0.4 0.6 0.8 1 Normalized Crack Length (c/Ro)
Elastic & Elastic-Plastic Comparison L = 30 ft, Imposed Rotation 1.00 0.95
- Crack Closure 0.90 0.85 0.80 M/Mo Elastic 0.75 EP - Initial Bending Stress = 30 ksi 0.70 0.65 0.60 0.55 0.50 0 0.2 0.4 0.6 0.8 1 Normalized Crack Length (c/Ro)
astic-Plastic Crack Driving Force Elastic-Plastic Analysis, L = 30 ft Initial Bending Stress = 30 ksi 4.50 Average Through-Thickness J, ksi-in 4.00 3.50 3.00 2.50 2.00 1.50 1.00 0.50 0.00 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Normalized Crack Length (c/Ro)
Secondary Stress Evaluation Surge Line Rotation Study Pete Riccardella May 31, 2007
Rotations in Pipe Fracture Experiments
- Test data reviewed to determine rotations due to presence of crack (at max load and fracture)
- Complex cracks vs, thru and surface cracks
- Complex cracks with various pipe/crack sizes
- All except surface crack sustained >2° at max load and >5° at fracture
- Surface crack sustained 1.7° rotation, but max load corresponded to ligament rupture, not fracture
Rotation Due to Crack - Complex vs.
Thru and Surface Cracks Crack Rotation Comparison (All Pipes 6" NPS; Different Crack Types) 40.0 35.0 30.0 4113-1 Complex; CF= 56.6%
Applied Stress (Pb; ksi) 25.0 4113-2 Complex; CF=76.7%
4131-5 Thru; CF=38.9%
20.0 4131-6 Surface; CF=36.9%
15.0 10.0 5.0 0.0 0.00 5.00 10.00 15.00 Rotation due to Crack (Deg.)
Rotation Due to Crack - Complex Cracks w/ Different Pipe/Crack Sizes Crack Rotation Comparison (All Complex Cracks; Different Pipe Sizes) 18.0 16.0 14.0 4113-1 NPS-6; CF= 56.6%
12.0 Applied Stress (Pb; ksi) 4113-2 NPS-6; CF=76.7%
4114-3 NPS-16; CF=58.5%
10.0 4114-4; NPS-16; CF=58.5%
8.0 6.0 4.0 2.0 0.0 0.00 5.00 10.00 15.00 Rotation due to Crack (Deg.)
Surge Line Piping Models
- Surge Line Piping Models developed for one CE and one Westinghouse plant in Group of Nine
- Models run with Thermal Expansion, Anchor Movements and Max Thermal Stratification Loads. Bending stresses at surge nozzle:
- 19.5 ksi in CE Plant
- 25 ksi in Westinghouse Plant
- Rotational Degrees of Freedom at surge nozzle node then released under same loading conditions to determine max rotation at surge nozzle that these loads could produce
CE Plant Surge Line Piping Model Hot Leg Surge Nozzle
W Plant Surge Line Piping Model Hot Leg Surge Nozzle
Nodal Release Results Summary of Results - Pressurizer Surge Nozzle Moment vs. Rotation Fixed-Fixed Bending Moments Fixed-Pinned Rotations (Deg.) Notes Mx, ft-kip My Mz Stress, ksi Rx, deg. Ry Rz SRSS CE Plant 176.303 43.701 5.771 19.485 1.38 0.66 0.97 1.81 1, 2, 3 Westinghouse Plant 138.881 103.841 3.809 24.854 1.13 1.08 0.84 1.77 1, 2, 4 Notes:
- 1. My is torsion direction.
- 2. Loads include thermal expnasion, anchor movement, and stratification
- 3. Stratification delta T is 320 F.
- 4. Stratification delta T is 270 F.
Conclusions
- Large Complex Cracks can sustain >2° rotation at crack
- even greater if additional flaw tolerance, beyond max load is credited
- Maximum rotation that could be produced at surge nozzle for two representative surge lines, under worst case secondary loads (thermal +
stratification) is <2°
- Therefore, these loads would be completely relieved prior to fracture
Implication of Wolf Creek Indications Verification and Confirmatory Analyses David Rudland, Heqin Xu, Do-Jun Shim, and Gery Wilkowski Engineering Mechanics Corporation of Columbus May 31, 2007 Innovative Structural Integrity Solutions 1
Outline K Verification Critical Crack Size Welding Residual Stress Convergence study - and other Relief Nozzle Calculations Leakage calculations Plans Innovative Structural Integrity Solutions 2
Continuous Arbitrary Surface Cracks Modified Bessel of the first kind 0.9 alpha=8, a/t=5, c=5 0.8 alpha=2, a/t=0.8, c=7 0.7 alpha=5, a/t=0.25, c=1.5 Developed 0.6 Extra Case by DEI 0.5 a/t 0.4 0.3 0.2 0.1 0
0 1 2 3 4 5 6 7 8 Surface Crack length (inch)
I (x ) = i J (ix )
2 J (x ) = cos( x sin )d 1
2 0 Innovative Structural Integrity Solutions 3
Continuous Arbitrary Surface Crack 1.0 0.9 0.8 Emc2 fit DEI 0.7 0.6 a/t 0.5 0.4 0.3 0.2 0.1 0.0 0.0 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 Surface crack length (in)
Innovative Structural Integrity Solutions 4
Continuous Arbitrary Surface Cracks 5
alpha=5, a/t=0.25, c=1.5 alpha=8, a/t=0.5, c=5 Applied loads - Tension 4 alpha=2, a/t=0.8, c=7 Extra Case and Bending only - No WRS 3
2 Used Wolf Creek relief 1
nozzle geometry 0
Wolf Creek relief nozzle
-1 loads - Phase 1
-2
-3
-4
-5 Innovative Structural Integrity Solutions 0 1 2 3 4 5 5
K-Verification 35 Case1 30 Seems unusual -
Case2 further QA required Case3 25 Case4 K, ksi*in0.5 20 15 10 5
0 0 1 2 3 4 5 6 7 8 Inner surface crack length, inch Innovative Structural Integrity Solutions 6
Degraded Piping Program TP304 Pipe Data Past complex cracked-pipe fracture test observations Lowers maximum loads (due to thickness reduction even for limit-load) and Lowers rotation due to the crack (from toughness reduction due to constraint) even for limit-load failures -
If reduction high enough, then may become EPFM failure for maximum load Innovative Structural Integrity Solutions 7
Past Complex-Cracked-Pipe Fracture Test Observations Most tests in past on nominal 6 diameter pipes TP304, Alloy 600, A106B One Alloy 600 pipe test with shim in compressive machined notch region to obtain full compression on crack closure side from start of initial loading Two tests on 16 diameter TP304 pipe Experimentally observed after the test that there was crack closure even in machined notch region on bottom of pipe (NUREG/CR-4082 V7, pg 2-7)
Change in calculated J-R curve proportional to measured decrease in CTOA with complex cracks Innovative Structural Integrity Solutions 8
Original EPRI Complex-Cracked Pipe Test Results Past complex cracked-pipe fracture test observations Used fit through Battelle data Innovative Structural Integrity Solutions 9
Change in Calculated J-R curve Proportional to Measured Decrease in CTOA with Complex Cracks Innovative Structural Integrity Solutions 10
Comparison of SIA and Emc2 Analysis of Complex-Cracked Pipe Tests - (Assumptions of no crack closure)
Innovative Structural Integrity Solutions 11
Emc2 Analysis With and Without Crack Closure, and With Complex-Crack Constraint Correction Innovative Structural Integrity Solutions 12
Summary for Complex-Cracked Pipe Maximum Moment Predictions Use one of following options - depending on QA of equations with data to be similar to Emc2 trends
- 1. Use no crack closure for limit-load analysis, with TWC Z-factor, or
- 2. Use NSC crack closure with 85% of DPZP equation with complex crack constraint correction on C(T) specimen Ji values (green curve fit previous slide)
Reasonable lower bound to experimental data, so negligible uncertainty Gives about the same results as 1.) for pressurizer nozzle sizes Innovative Structural Integrity Solutions 13
Welding Residual Stress From May 1st meeting Surge Nozzle
- Typical Type 8 geometry with no repairs. Includes the A182 filler weld for the thermal sleeve
- Same as Type 8 expect with a 0.5 (or maybe 5/16) deep weld repair - Geometry shows 5/16 from bottom of bevel
- CE nozzle (Type 9). This could be similar to Type 8 except without the filler weld.
- One of these cases with the stainless steel safe end weld.
Would suggest Type 8.
Innovative Structural Integrity Solutions 14
Welding Residual Stress Relief/Safety Nozzle
- Typical unrepaired geometry without a liner - Type 1a (like Wolf Creek)
- Typical unrepaired geometry with liner - Type 2b
- Typical geometry without a liner with deep (40-70%) ID repair - Not on DEI list. They plan a repair on liner geometry
- Typical geometry without a liner with stainless steel safe end repair
- Combination of 3.) and 4.)
For confirmatory calculations, want to start with exact same geometry - DEI sent Surge nozzle geometry on 5/17, Relief nozzle geometry on 5/29 With new information about ID last pass weld, should we consider spray nozzle WRS?
Innovative Structural Integrity Solutions 15
Surge Nozzle Geometry from DEI Innovative Structural Integrity Solutions 16
Surge-line Welding Residual Stress Innovative Structural Integrity Solutions 17
Surge-line Welding Residual Stress Surge WRS status:
Mesh complete As of 5/30/07 - Thermal analyses underway Anticipated completion date: 6/7/07 Relief WRS status:
Received geometry: 5/29/07 Anticipated completion: 6/15/07 Innovative Structural Integrity Solutions 18
Surge Nozzle Welding Results - original results 60 Surge FE results 15% 360deg last pass 50 Surge Nozzle 15% 360deg last pass Surge Nozzle 40 Weld residual stress, ksi 30 20 10 0
-10
-20
-30 0 0.2 0.4 0.6 0.8 1 Nomalized Distance from ID Surface 2D Axi-symmetric analyses conducted -
Innovative Structural Integrity Solutions Results used in scoping analyses 19
Welding Repair Work - Battelle through MERIT Battelle (Bud Brust) conducted a surge nozzle WRS 3D solution to compliment 2D axi-symmetric solution generated earlier.
First conducted un-repaired (but still contains 15% -
360 last pass weld)
Then conducted 26% deep - 90degree weld repair Results are welding stresses only Innovative Structural Integrity Solutions 20
Welding Repair Work - Battelle through MERIT Preliminary Butter Pass Weld Pass V1 5 9 10 11 4 9 8
8 7
6 3 7 5
4 3
X 2 6 2 Y Z 1 1 Innovative Structural Integrity Solutions Geometry slightly different than analyzed in this effort 21
Axial Stresses - last pass 15%-360-Deg. weld Preliminary Axis-symmetric 250. 150. 50. -50. -150. -250.
3D Solution 180-Degree Location Y
X Z Innovative Structural Integrity Solutions 22
Welding repair Preliminary 90-Degree Repair 225-Degree Repair Cross Section Station 135-Degree (26% Through Thickness)
Station Y
X Z 135-degree 135-degree Grind/Repair Grind/Repair Y
Z End Location Start Location X
Innovative Structural Integrity Solutions 23
Comparison of Stresses Along Circumference 90-Degree Repair Preliminary 270-Degree 90-Degree Station Station (Normalized (Normalized Distance = 1.0) Distance = 0.0)
At a depth of 15%t Surge - with and without 90-repair weld Alloy 182 Axial Stress - No Stresses at Weld Centerline repair 350 300 Axial Stress (Mpa)
Axial Stress (90-250 degree Repair) 200 End Weld 150 Start Weld Repair Repair Station 225-degrees 100 Station 135-degrees 50 0
0 0.5 1 1.5 Normalized Distance along circumference Innovative Structural Integrity Solutions 24
Comparison With and Without Weld Repair Preliminary Butter (max-Surge - with repair weld mean) - Axis-Alloy 182 Sym Butter (max-400 mean) 3D 300 Axial Stress (Mpa)
Butter (max-200 mean) 3D 90-degree Repair 100 (180 pos.)
0 0 10 20 30 40 50
-100
-200 Distance from ID (mm)
Innovative Structural Integrity Solutions 25
Convergence Study Conducted additional Wolf Creek relief nozzle cases to investigate convergence 1 month, 0.5 month and 0.25 month time steps Looked at fit to original relief WRS Looked at 65% bending moment 0.25 month time step still running, but appears converged at 0.5 month Solution for time to leakage very sensitive to WRS 65% bending moment leaked at ~29 years Innovative Structural Integrity Solutions 26
Comparison of Time-to-Leak - DEI WRS Dashed line - 0.25 mo 1.2 Symbols - 0.5mo Time = 0.333 yr by EMC2 Solid lines - 1mo Time = 1.000 yr by EMC2 Time = 2.000 yr by EMC2 1 Time = 3.000 yr by EMC2 Time = 4.000yr by EMC2 Time = 5.00 yr by EMC2 Tme = 5.47 yr by EMC2 0.8 Crack Depth (in)
Using DEI March 20 WRS 0.6 0.4 0.2 1 mo - 5.65 year at leak 0.5 mo - 5.40 year at leak 0.25 mo - still running 0
0 1 2 3 4 5 6 7 8 Circumferential Distance along ID (in)
Using DEI March 20 WRS Innovative Structural Integrity Solutions 27
Comparison of Time-to-Leak - Emc2 WRS 1.2 Time, years First leakage 6.6 years 0 0.25 1
1 2
3 Crack Depth (in) 0.8 4 5
6 0.6 6.7129 6.5 0.4 0.2 0
0 1 2 3 4 5 6 7 8 Circumferential Distance along ID (in)
Using Emc2 fit to relief nozzle scoping WRS Innovative Structural Integrity Solutions 28
Comparison of WRS Estimation 70 original 60 DEI - March 20 - 5.36 years 50 Emc2 - Final - 6.5 years DEI - May 8 - 7.5 years Axial Welding Residual Stress (ksi) 40 30 20 10 0
-10
-20
-30 0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 Normalized Distance from ID Surface, (r-ri)/t Innovative Structural Integrity Solutions 29
Wolf Creek Relief with 65% Bending Stress Time, years Conducted 1.2 28.5625 same analyses 6.1667 but with 65%
1 100% Moment bending stress Time to leakage Crack Depth (in) 0.8
= 29 years 0.6 As surface crack 0.4 65% Moment penetrates wall, profiles similar 0.2 0
0 1 2 3 4 5 6 7 8 Circumferential Distance along ID (in)
Innovative Structural Integrity Solutions 30
Leak and Critical Crack Size Calculations Used Wolf Creek relief nozzle case - Emc2 fit to WRS Calculated leakage using SQUIRT, PWSCC crack morphology parameters, COD dependence Assumed elliptical opening COD from FEA 100% quality steam Used arbitrary NSC analyses with SS flow stress - with crack closure Applied correction for limit load 1/0.85 - Per earlier slides -
DPZP>1 Included all displacement controlled loads - conservative Innovative Structural Integrity Solutions 31
Leak Rate Results 5
4 12 Wolf Creek Relief Nozzle 3 10 2
8 Leak rate, gpm 1
6 0
0 1 2 3 4 5 4
-1 100% bending 2 65% bending -2 0 -3 0 2 4 6 8 10 12 OD crack length, inch -4 Critical Crack
-5 Margin = 1 on N+SSE Preliminary Innovative Structural Integrity Solutions 32
Wolf Creek Relief Nozzle Leak Rates 12 100% bending 10 65% bending Critical Crack Margin 1.4- N 8 Critical Crack Margin 1.0 - N+SSE Leak rate, gpm 2.7 - N 1.9 - N+SSE 6
Critical Crack Margin 4 3.8- N Critical Crack Margin 2.7 - N+SSE 3.9 - N 2.8 - N+SSE 2
0 0 2 4 6 8 10 12 Time from first leakage, months Preliminary Innovative Structural Integrity Solutions 33
Plans + Tentative Schedule to Complete Review and verify secondary stress knock down factor -
6/8/2007 Finalize K verification - 6/8/2007 Continue WRS analyses - 6/15/2007 Confirmatory calculations for sensitivity matrix - 6/29/2007 WRS validation effort (Scope still need further refinement) -
7/31/2007 Innovative Structural Integrity Solutions 34
Preliminary NRC Comments on the Industry Proposed Sensitivity Matrix E. Sullivan, S. Sheng, D. Rudland, & Al Csontos June 1, 2007
Comments on the Industry Proposed Sensitivity Matrix
- Industrys proposed sensitivity matrix was well conceived, developed, and organized
- Proposed sensitivity matrix is a solid start
- A few more cases need to be evaluated:
- Surge line with/without thermal expansion stresses
- Cases 9 & 10 may need to use a revised WRS profile since the DMW/SS safe-end separation is large (6.8)
- Evaluate an intermediate case between the above arrest and high Pb and Pb/(Pm+Pb) for one or two configurations
- Varying axisymmetric WRS profiles (next slide)
- Other cases as results develop U.S. Nuclear Regulatory Commission 2
Comments on the Industry Proposed Sensitivity Matrix
- Industrys April 9th presentation:
- 26 axisymmetric, self-balancing WRS profiles
- ID stress = 54 ksi U.S. Nuclear Regulatory Commission 3
Comments on the Industry Proposed Sensitivity Matrix - Outputs
- PICEP and SQUIRT leak rate models provide mean values and may need to be evaluated either through sensitivity or safety factors for:
- Detectable leakage
- Maximum leakage prior to rupture
- NRC staff does not understand why the time from initial flaw to rupture should be compared to the operating age of each subject plant?
- NRC staff does not understand why varying the 8 sensitivity parameters can be related to the operating age of each subject plant?
U.S. Nuclear Regulatory Commission 4
Pressurizer Nozzle Fabrication History (DRAFT)
Plants C and F Cameron Martin Wolf Creek Task Group Meeting May 31 - June 1, 2007 1
DRAFT: Plant C Pressurizer Nozzle Repair History Repair Part Description Defect Description Repair Description Number 1 Surge nozzle weld buildup Porosity in weld; rejected by RT Removed defect, PT, then repaired weld (twice) with Alloy 182 2 Safe end to surge nozzle weld Welded safe end to nozzle with wrong weld See repair #5 procedure 3* Surge nozzle cladding PT of cladding; one indication after PWHT Repaired by temper-bead with 309 and 308 stainless steel.
4* Safe end to surge nozzle weld Rejected for weld defects per RT Removed defects, repaired weld with Alloy182.
5* Safe end to surge nozzle weld In Repair #2 the incorrect weld procedure Removed and replaced safe end. Reattached was used to weld the safe end to the surge safe end to nozzle with Alloy 82/182.
nozzle.
6 Spray, safety & relief nozzles Bores of upper head nozzles are too large to Weld build-up the oversized bores using 308L (A, B. C, D and E) permit proper gaps and seating of liners. Stainless Steel. Then bores machined to size.
7 Spray, safety & relief nozzles After #6 repairs and machining, bores Accept size as-is; liners rolled into place.
(A, B. C, D and E) remain slightly oversized with respect to the liner outside diameter.
- - Repair number's 2 and 4 are irrelevant because the safe end to surge nozzle weld was completely replaced in repair number #5.
2
DRAFT: Plant C (continued)
Pressurizer Nozzle Repair History Repair Number Part Description Defect Description Repair Description 8 Spray, safety & relief nozzles Lengths of liners are greater than the Cut and re-installed liners to ensure best (A, B. C, D and E) design dimensions. Cant get proper possible seating; rolled using standard seating; gap too large. procedures.
9 Safety/relief Safe end was mis-machined; incorrect Accepted as-is; main deviation on outside nozzle C angle angle.
10 Safe end to Safety/relief RT located defect in the safe-end Ground out defect repaired by temper bead nozzle A weld attachment weld; occurred at interface of using Alloy 182.
weld and buttering 11 Safety/relief nozzle C PT indications on cladding of the nozzle Removed safe-end and repaired build up cladding and weld and at safe-end attachment weld with Alloy 182. The build up was then PWHT. The safe end was then reattached to the nozzle using Alloy 82/182.
3
DRAFT: Plant F Pressurizer Nozzle Repair History Repair Part Description / Test Defect Description Repair Description Number No.
Grinding of R.T. defects in nozzle to safe-end weld SS safe end cut off. Butter machined off to original 1 Spray Nozzle E caused base metal 1/8"W x 1/2"D x 6"L to be base metal. Etched surface. Re-build up butter with exposed after PWHT. Alloy 182. See Repair #2.
- 1. Defects in machining of build-up (butter) 1. Lightly blended out step defect in build-up while including 1/32" step in bore ID located 1 5/16" maintaining wall above minimum. R.T. accepted.
down from lip & blending on OD at bond line. See Repair #3.
2* Spray Nozzle E
after PWHT). 3. Weld build-up end of short safe end with 308L
- 3. Safe end length = 4.61" is out of tolerance. stainless steel.
Nozzle Build-up (butter) P.T. indications due to Bead temper repaired part of the exposed base metal 3* Spray Nozzle E porosity. Grinding of indications after PWHT cavity with Alloy 182. Then completed the weld exposed base metal. Wall was not reduced. repair with Alloy 82. See Repair #4.
Nozzle Build-up (butter) R.T. rejected areas.
Defect was removed. X-ray showed linear indications 4* Spray Nozzle E Indications run 360o around nozzle for a depth of remained, depth of 1/2". R.T. rejected. See Repair #5.
9/16" from I.D.
Ground additional 1/8" at upper wall only. X-ray Nozzle Build-up (butter) R.T. rejected areas.
5* Spray Nozzle E showed traces of original indications in some areas.
Indications remained.
R.T. rejected. See Repair #6
- - Repair number's 2, 3, 4, 5, 6, 7, 9, and 10 are irrelevant because the spray nozzle weld build up underwent repair and PWHT in repair number 11.
4
DRAFT: Plant F (continued)
Pressurizer Nozzle Repair History Repair Part Description / Test Defect Description Repair Description Number No.
Nozzle Build-up (butter) R.T. rejected areas. Some Ground additional 3/16". R.T. of cavity accepted.
6* Spray Nozzle E indications remained. See Repair #7.
Nozzle Build-up (butter) P.T. rejected. Base metal Machined off Inconel build-up, etched surface and 7* Spray Nozzle E exposed 360o x 0.5" W x 0.375" D at bond line. recorded dimensions.
Sketch with size and location. See supplement 1.
Nozzle dimensions out of tolerance after removal of Weld repaired nozzle to restore nozzle length with 8 Spray Nozzle E Build-up (butter). Alloy 182. See Repair #9.
Nozzle Build-up dimensions out of tolerance after Weld Build-up restored to drawing dimensions 9* Spray Nozzle E machining. including tie-in weld with Alloy 182. See Repair #10 Nozzle Build-up needs repair of P.T. indications Areas ground and weld repaired with Alloy 82. See 10* Spray Nozzle E before PWHT. No base metal exposed. Repair #11.
Areas ground and weld repaired with Alloy 82.
Nozzle Build-up needs repair of remaining P.T.
11* Spray Nozzle E Local PWHT. Welded safe end to nozzle with Alloy indications before PWHT. No base metal exposed.
82/182.
- - Repair number's 2, 3, 4, 5, 6, 7, 9, and 10 are irrelevant because the spray nozzle weld build up underwent repair and PWHT in repair number 11.
5
Conclusions Plant C
- No I.D. DM weld repairs Plant F
- Spray Nozzle
- Final repair to nozzle buttering included local PWHT 6