ML16078A411
| ML16078A411 | |
| Person / Time | |
|---|---|
| Site: | Indian Point  |
| Issue date: | 01/16/2014 |
| From: | NRC/OGC |
| To: | Atomic Safety and Licensing Board Panel |
| SECY RAS | |
| References | |
| RAS 51011, ASLBP 07-858-03-LR-BD01, 50-286-LR, 50-247-LR | |
| Download: ML16078A411 (3) | |
Text
NRC000235 Submitted: March 18, 2016 IELECTRIC POWER RESEARCH INSTITUTE MRP Materials Reliability Program MRP 2014-002 (via e-mail)
January 16, 2014 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001
Subject:
Proposed Edits to WCAP-17096-A Draft As discussed at a public meeting with NRC staff in May 2013, this letter provides proposed text revisions for draft WCAP-17096-NP Revision 2. Changes were made based on the NRC RAIs, draft Safety Evaluation, and lessons learned from recent plant-specific work performed by AREVA and Westinghouse. The updated text has been reviewed by the PWR Owner's Group Materials Subcommittee (MSC) and comments have been incorporated.
Subsequent letters from EPRI-MRP will provide additional proposed text revisions from Westinghouse.
Sincerely, Tim Wells Anne Demma Chairman, Integration Committee Program Manager EPRI-Materials Reliability Program EPRI- Materials Reliability Program Cc: Joe Holonich, NRC James Molkenthin, PWROG Program Manager Docket No. 669 Together ... Shoping the Future of Electricity PALO ALTO OFFICE 3420 Hillview Avenue, Palo Alto, CA 94304-1338 USA o 650.855.2000
- Customer Service 800.313.3774
- www.epri.com Section ,or %.RCRAT Rema rks:
page of
~WZAýP- - . ,N::
1,709 6- 'Rev.2 required in MRP-227. required in IRP-227.
The top portion of the uppermost former plate is partially The former plates are partially accessible through accessible from above the core barrel assembly and openings in the core barrel assembly and could portions of the remaining former plates are partially potentially be VT-3 examined. accessible through openings in the core barrel assembly that could potentially be VT-3 examined if techniques were required to be developed, but substantial Nothing is required for examination at this time.
development efforts would be needed, which is why they are not currently required to be examined.
Nothing is required for examination at this time.
4 4 I. L Page A-47 N/A Methodoloyv and Data Reouirements: Methodology and Data Requirements: Methodology revision The general analytical methodology to be used for The general analytical methodology to be used for acceptance criteria for the former plates involves the acceptance criteria for the former plates involves the following steps and inputs:
following steps and inputs:
" Perform an evaluation to assess the potential of Confirmation of required loading and degradation with respect to the baffle plates
" This wvill include comparison of similarity of combination requirements materials, accumulated irradiation fluence and stresses in the former plates versus the baffle Perforn a linear-elastic fracture mechanics plates (LEFM) evaluation to determine the critical Excluding the stresses in the formner plates at the crack size using the MRP-21 1 fracture toughness threaded holes it is expected that the former plates will be shown to be less susceptible to embrittlement than the values baffle plates.
A flaw handbook could also be If the above effort is inconclusive then the possibility of developed limited examnination of the former plate will be assessed, wvith the objective of confirming that the former plates had not cracked through to the surface around the Or, justify the existing calculations in threaded connections.
Page 40 of 59 Section or NRC RAI Current Wording: Proposed:ReV.ision Remarks:
page of 17096 Rev. 2 ____________________..____"__"_____...__...__
MRP-210 Analytical efforts could be performed on a generic basis.
0 An operability evaluation to operate at least one cycle based on possible degradation of the former plates should be performed
- An evaluation of the consequences of leaving cracked former plates in place should be performed Analytical efforts could be performed on a generic basis.
Page A-50 N/A Methodology and Data Requirements: Methodology and Data Requirements: Methodology revision The general analytical methodology to be used for The general analytical methodology to be used foracetnerirafothBBblsnvvste acceptance criteria for the BB bolts involves the acceptance criteria for the BB bolts involves the following steps and inputs:
following steps and inputs:
A global FEM model is developed to evaluate A global FEM model is developed to evaluate failures for use in developing the frequency for the failures for use in developing the frequency for I&E guidelines, acceptable failure pattern or the I&E guidelines, acceptable failure pattern or numbers, and for use in preparing possible JCOs numbers, and for use in preparing possible JCOs for the BF and CF bolts for the BF and CF bolts o Evaluations for these bolt locations will consider BB bolts to be failed and Evaluations for these bolt locations structurally inactive will consider BB bolts to be failed o No specific pattern will need to be and structurally inactive evaluated as the BB bolts do not perform any core support function, nor are they required to maintain the geometry of the No specific pattern will need to be core cavity evaluated as the BB bolts do not o In addition, no specific acceptance criteria Page 41 of 59 NRC000235 Submitted: March 18, 2016 IELECTRIC POWER RESEARCH INSTITUTE MRP Materials Reliability Program MRP 2014-002 (via e-mail)
January 16, 2014 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001
Subject:
Proposed Edits to WCAP-17096-A Draft As discussed at a public meeting with NRC staff in May 2013, this letter provides proposed text revisions for draft WCAP-17096-NP Revision 2. Changes were made based on the NRC RAIs, draft Safety Evaluation, and lessons learned from recent plant-specific work performed by AREVA and Westinghouse. The updated text has been reviewed by the PWR Owner's Group Materials Subcommittee (MSC) and comments have been incorporated.
Subsequent letters from EPRI-MRP will provide additional proposed text revisions from Westinghouse.
Sincerely, Tim Wells Anne Demma Chairman, Integration Committee Program Manager EPRI-Materials Reliability Program EPRI- Materials Reliability Program Cc: Joe Holonich, NRC James Molkenthin, PWROG Program Manager Docket No. 669 Together ... Shoping the Future of Electricity PALO ALTO OFFICE 3420 Hillview Avenue, Palo Alto, CA 94304-1338 USA o 650.855.2000
- Customer Service 800.313.3774
- www.epri.com Section ,or %.RCRAT Rema rks:
page of
~WZAýP- - . ,N::
1,709 6- 'Rev.2 required in MRP-227. required in IRP-227.
The top portion of the uppermost former plate is partially The former plates are partially accessible through accessible from above the core barrel assembly and openings in the core barrel assembly and could portions of the remaining former plates are partially potentially be VT-3 examined. accessible through openings in the core barrel assembly that could potentially be VT-3 examined if techniques were required to be developed, but substantial Nothing is required for examination at this time.
development efforts would be needed, which is why they are not currently required to be examined.
Nothing is required for examination at this time.
4 4 I. L Page A-47 N/A Methodoloyv and Data Reouirements: Methodology and Data Requirements: Methodology revision The general analytical methodology to be used for The general analytical methodology to be used for acceptance criteria for the former plates involves the acceptance criteria for the former plates involves the following steps and inputs:
following steps and inputs:
" Perform an evaluation to assess the potential of Confirmation of required loading and degradation with respect to the baffle plates
" This wvill include comparison of similarity of combination requirements materials, accumulated irradiation fluence and stresses in the former plates versus the baffle Perforn a linear-elastic fracture mechanics plates (LEFM) evaluation to determine the critical Excluding the stresses in the formner plates at the crack size using the MRP-21 1 fracture toughness threaded holes it is expected that the former plates will be shown to be less susceptible to embrittlement than the values baffle plates.
A flaw handbook could also be If the above effort is inconclusive then the possibility of developed limited examnination of the former plate will be assessed, wvith the objective of confirming that the former plates had not cracked through to the surface around the Or, justify the existing calculations in threaded connections.
Page 40 of 59 Section or NRC RAI Current Wording: Proposed:ReV.ision Remarks:
page of 17096 Rev. 2 ____________________..____"__"_____...__...__
MRP-210 Analytical efforts could be performed on a generic basis.
0 An operability evaluation to operate at least one cycle based on possible degradation of the former plates should be performed
- An evaluation of the consequences of leaving cracked former plates in place should be performed Analytical efforts could be performed on a generic basis.
Page A-50 N/A Methodology and Data Requirements: Methodology and Data Requirements: Methodology revision The general analytical methodology to be used for The general analytical methodology to be used foracetnerirafothBBblsnvvste acceptance criteria for the BB bolts involves the acceptance criteria for the BB bolts involves the following steps and inputs:
following steps and inputs:
A global FEM model is developed to evaluate A global FEM model is developed to evaluate failures for use in developing the frequency for the failures for use in developing the frequency for I&E guidelines, acceptable failure pattern or the I&E guidelines, acceptable failure pattern or numbers, and for use in preparing possible JCOs numbers, and for use in preparing possible JCOs for the BF and CF bolts for the BF and CF bolts o Evaluations for these bolt locations will consider BB bolts to be failed and Evaluations for these bolt locations structurally inactive will consider BB bolts to be failed o No specific pattern will need to be and structurally inactive evaluated as the BB bolts do not perform any core support function, nor are they required to maintain the geometry of the No specific pattern will need to be core cavity evaluated as the BB bolts do not o In addition, no specific acceptance criteria Page 41 of 59