ML20213E018
| ML20213E018 | |
| Person / Time | |
|---|---|
| Site: | Vogtle  |
| Issue date: | 10/31/1986 |
| From: | Conway R GEORGIA POWER CO. |
| To: | Youngblood B Office of Nuclear Reactor Regulation |
| References | |
| GN-1157, NUDOCS 8611120372 | |
| Download: ML20213E018 (9) | |
Text
,.,A Georgta Power Company 333 Pedmont Avenue At:anta Georgta 30308 TJeanone 404 526 6724 Ma+ng Addrew Post Ottee Box 4545 Atlanta. Georgia 30302 R. E. Conway.
Senior Vice President October 31, 1986 Director of Nuclear Reactor Regulation File:
X3BL01 Attention: Mr. B. J. Youngblood Log:
GN-1157 PWR Project Directorate #4 Division of PWR Licensing A U. S. Nuclear Regulatory Commission Washington, D.C.
20555 NRC DOCKET NUMBERS 50-424 AND 50-425 CONSTRUCTION PERMIT NUMBERS CPPR-108 AND CPPR-109 V0GTLE ELECTRIC GENERATING PLANT - UNITS 1 AND 2 SER OPEN ITEM 1:
EQUIPMENT QUALIFICATION
Dear Mr. Denton:
As requested in SER Supplement No.
3, Georgia Power Company hereby reports the status of the Seismic Qualification Program at VEGP.
Georgia Power Company confirms that the Seismic and Dynamic Qualification of safety-related electrical and mechanical equipment is complete to the best of our knowledge at this time except for the following:
EQDP X4AJ07 Review of qualification report for AAF ESF equipment EQDP X4AJ06 AAF nozzle load modification EQDP X4AJ16 Resolution of potential overstressed nozzle loads condition on CVI cooling units EQDP X3AJ01A/B Conformance to as built condition for Calvert cable bus duct Completion of the deismic Qualification Program will consist of evaluation of these outstanding qualification issues, evaluation of properly installed pumps and valves, evaluation of laterally supported actuators, and verification of as-built loads for pumps and valves.
The qualification program will be complete by December 1,1986.
A complete response to SER Supplement No. 3 is attached.
Attachment I addresses Seismic and Dynamic Qualification issues and Attachment 2 provides a response to Pump and Valve Operability issues.
8611120372 861031 g%
DR ADOCK 0500 4
g I r
Director of Nuclear Reactor Regulation File: X3BL01 October ~31, 1986 Log:
GN-1157.
Page two Should there be any questions, please do not hesitate to contact me.
Sincerely, R. E. Conway REC / JAB /wk1 Attachment xc:
R. A. Thomas J. E. Joiner, Esquire B. W. Churchill, Esquire M. A. Miller (2)
- 8. Jones, Esquire G. Bockhold, Jr.
NRC Regional Administrator NRC Resident Inspector D. Feig R. W. McManus L. T. Gucwa Vogtle Project File
r Seismic and Dynamic Qualification SSR 3, Section 3.10.1.3 - Generic Items Generic Item 1: The FSAR must be revised to incorporate the new stress limits to ensure the operability of replacement pumps, if needed, in the future.
GPC Response: FSAR Table 3.9.B.3-5 was revised in Amendment 27 to verify the calculated stresses are below yield stress for active pumps in the emergency and faulted conditions.
Generic Item 2:
Confirm the com}1etion of the seismic qualification program with special emphasis on valves with laterally supported actuators.
GPC Response: Refer to cover letter.
Generic Item 3:
Confirm completion of verification of as-built loads for pumps and valves.
GPC Response: Refer to cover letter.
Generic Item 4: The FSAR should be updated to address the following:
(a) Where did the deformation limit of Section 3.9.B.3.5 come from?
(b) What is the basis for operability of safety-related systems under faulted condition loadings?
(c) Sections 3.10.B.4.2 and 3.10.N.4.2 state that aging and sequential testing of safety-related mechanical equipment was not performed.
However, this is contradicted in Section 3.11.B.2.
GPC Response:
(a) PSAR Section 3.9.B.3.5 was revised in Amendment 27 to reflect the source of the deformation limit.
(b) PSAR Table 3.9.B.3-5 was revised in Amendment 27 to verify that calculated stresses are below yield stress for active pumps under faulted condition loadings. This verification will predict operability.
(c) The inconsistencies between FSAR Sections 3.10.B.4.2, 3.10.N.4.2, and 3.11.B.2 were removed in Amendment 27. These PSAR sections now address the methodology used in qualifying safety-related mechanical equipment.
SSR 3, Section 3.10.1.4 - Equipment-Specific Items Equipment-Specific Item 1: The staff should be informed of the satisfactory completion of the plasma display and keyboard qualification through inclusion of the requirements into the M/S program.
GPC Response: Based on the results of aging of a large and comprehensive sample of electrical and electronic components, a 5 year qualified life has been recommended by Westinghouse. No specific aging mechanisms have been identified for these components within this time period. Therefore, GPC has incorporated a 5 year life for the plasma display and keyboard into the M/S Program.
Equipment-Specific Item 2:
Consider the thermal stresses on the header of the Containment Building Normal Air Cooling Rack and provide a summary of the results.
GPC Response: The reactor cavity cooling coil performs no safety-related function. The nuclear service water, which provides the cooling medium for the coil is isolated during accident conditions (both inlet and outlet) and therefore is not a concern. However, the vendor's preliminary thermal stress calculations have been reviewcd and found to be within ASME allowable stress limits for nozzles between the main header and branch piping headers.
Final calculations will be reviewed and verified to be acceptable by November 14, 1986.
Equipaent-Specific Item 3:
Consider seismic loads in the stress evaluation of the auxiliary feedwater pump boundary components and provide the results.
GPC Response: The stress evaluation and results were provided in letter GN-1094 dated September 30, 1986. The results demonstrated that the deadweight and seismic effects were insignificant when compared to pressure effects. Therefore, these loads were not included for certain boundary components.
Equipment-Specific Item 4:
Provide a copy of the planned maintenance and surveillance program incorporating the hattery changeout frequency.
GPC Response - The Battery Maintenance Procedure 25093-C and checklists were provided in letter GN-1094 dated September 30, 1986. The checklists require a 10 year hattery changeout frequency.
3
r Pump and Valve Operability Assurance SSER 3, Section 3.10.2.2 - SEE Issues SER Issue 1: The PSAR needs to be amended to include a description of the criteria for the maintenance program, as it relates to equipment qualification test and analysis results. The amendment should also describe how mechanica?.
aging of safety-related equipment was considered.
GPC Response: A description of the maintenance program as it relates to equipment qualification test and analysis results has been included in Amendment 27 to FSAR Section 3.11.B.2 and referenced in FSAR Section 3.11.N.2.
Mechanical aging of safety-related equipment is also addressed in Amendment 27 in the same FSAR Sections.
SER Issue 2: This issue, concerning static shaf t analysis, has been closed.
SER Issue 3: The FSAR needs to be amended to address an assessment of degraded conditions and how testing was tailored to meet SRP Section 3.10, Paragraph II.la(2). The amendment should also include a commitment to RG 1.148 for replacement components.
GPC Response:
FSAR Sections 3.9.B.3.2.2 and 3.10.N.2.2.2 were revised in Amendment 27 to address degraded conditions, testing, and RG 1.148.
SER Issue 4: This issue, concerning methods and standards used for qualification, has been closed.
SER Issue 5: This issue, concerning components qualified by analysis alone, has been closed.
SER Issue 6: The FSAR needs to be amended to reflect how separate components qualification was addressed.
CPC Response:
FSAR Sections 3.10.B.2.1 and 3.10.N.2.2 were revised in Amendment 27 to address pump / motor qualification.
SER Issue 7: The FSAR needs to be amended to provide a description of the generic check valve testing criteria.
GPC Response:
FSAR Sections 3.9.B.3.2.2 and 3.10.N.2.2.2 were revised in Amendment 27 to address the generic check valve testing criteria.
SER Issue 8: The FSAR needs to be amended to provide a description of the administrative controls for component qualification.
GPC Response PSAR Sections 3.11.B.2 and 3.11.N.2.1 were revised in Amendment 27 to address administrative controls for component qualification.
r SSER 3, Section 3.10.2.3 - Operability Issues (Specific)
Specific Issue 1: Provide assurance that the vendor recommendations for the disassembly of the APW turbine are invoked by the Vogtle maintenance program..
GPC Response: The Maintenance Checklist from turbine procedure 27571-C was provided in letter GN-1094 dated September 30, 1986. The checklist incorporates the 5 year inspection frequency which was recommended by the vendor.
Specific Issues 2:
Provide evidence that the AFW turbine pump trip and i
throttle valve can be operated manually and electrically against the maximum differential pressure.
GPC Response: During hot functional testing, it was determined that _the AFW turbine pump trip and throttle valve could not be easily manually opened against the maximum delta P.
As a result, the preoperational test was changed to close an isolation valve (HV-5106) upstress of the trip and throttle valve, unseat the trip and throttle valve and then open the isolation valve to allow steam flow to the turbine pump. Following this change, manual throttling of stese flow was achievable. Operating procedure 13610-1 is being revised to reflect this change. The revised operating procedure and preoperational test results should be available by November 21, 1986 Specific Issue 3: The review of the safety injection pump (tag no.
11204P6004) identified concerns regarding operation with entrained debris.
The applicant shall:
(a) modify the appropriate qualification documents to describe how operability of the safety injection pump will not be adversely affected by the presence of 1/8-in. debris in the fluid (b) provide a copy of the test report that references operability of the centrifugal charging pump with entrained debris (c) describe the applicability of the charging pump test data to the operation of the safety injection pump
[
GPC Response (a) The appropriate evaluations for operability of VEGP Safety Injection Pumps with entrained debris will be incorporated into the NSSS EQDP (X6AA15). However, the actual test report entitled " Particle Injection and Thermal Transient Test for Pacific Pump Shop Order VN 49752" will be maintained by Westinghouse.
(b) Due to the proprietary status of the test data the test report will not be provided but maintained by Westinghouse and available for NRC review.
However, the test results were provided in letter GN-986 dated July 10, 1986. The test demonstrated pump operability with no signs of adverse wear from observation 'of the disassembled pusp.
Furthermore, there were no signs of mechanical seal leakage before, during or after the test.
The test data has been reviewed and accepted on several other audits.
l u
(c) The impe11ers, wear rings, and seals provided on the Vogtle pump are manufactured from the same specially selected =aterials as those of the tested pumps. The materials were selected because of their wear resistant properties. The design (i.e. clearance, diameter, configuration, etc.) for the tested pumps are very similar to that found in the Vogtle pumps.
Specific Issue 4:
Describe the flow measurements and trending analysis to ensure operability of -check valves.
GPC Response: In mode 1, at 100% power, the design flow for the main feedwater system would be met and the 16 inch feedwater check valve would be full open on its stop. At power levels below approximately 98%, flutter may occur. However, it is GPC's intention to operate the plant at 100% power a greater percentage of the time.
Total feedwater flow is monitored by operations department personnel via the plant computer system. Any feedwater flow anomaly will be investigated to determine the cause and what effects the anomaly had on plant equipment.
As previously stated in the July 10, 1986 response feedwater check valves 1-1305-U4-071, 073, 075, and 077 are disassembled and manually stroked on a staggered test basis at refueling. If the check valve inspected shows significant degradation, the remaining three feedwater check valves will be disassembled and inspected. The root cause of the valve degradation will be investigated and the potential for common mode failure mechanisms will be evaluated. If the evaluation deems it necessary, other potentially affected valves will be disassembled and inspected based on a sampling program.
In general, a deficiency report (DR) is generated for all safety-related equipment failures. All DRs are trended to identify remaining deficiencies that could adversely affect the quality of the plant and associated equipment. A root cause determination review and corrective action identification are performed when necessary.
GPC will participate in the NSSS Owners Group Task Force on Check Valves. The recommendations from the group will be evaluated for applicability to Vogtle.
In particular, an acoustic / vibration analysis program will be evaluated as an input to preventative maintenance for check valves.
Specific Issue 5: This issue, concerning Namco Limit Switch qualification, has been closed.
SSER 3, Section 3.10.2.3 - Operability Issues (Generic)
Ceneric Issue 1: Describe how the flow measurements for the feedwater system check valves will be performed.
Confirm that a trending evaluation of the data will be done.
Indicate how the flows for valves 11302U4125, -126, -127, and -128 will be measured. Consider leak testing check valves for verification of operability, considering the industry's experience with main feedwater check valves.
GPC Response: The feedwater system check valves will not receive any flow measurements directly. The total feedwater flow is monitored by Operations personnel via the plant computer system. Design engineering has determined the main feedwater line will receive the remaining 9%.
Operations personnel wil1~ report any feedwater flow anomalies, and they will be investigated to determine the cause and any effects on plant equipment.
Specifica concerning the inspection of feedwater check valves are given in response to specific issue number four.
Generic Issue 2: To ensure proper thread engagement for mechanical flanges the applicant shall provide the following:
(a) Identify the criteria that should be met.
(b) Demonstrate that all the mechanical (flange, anchor, bolt, etc.)
connections are in compliance with the criteria by performing an appropriate sampling program evaluation.
(c) Demonstrate that actions have been taken that will prevent future noncompliance. This issue remains open.
CPC Response:
)
(a) The criteria for nut / bolt thread engagement is documented in Pullman Procedure IX-1 for Concrete Anchors and Pullman Procedure IX-5 for 4
l threaded fasteners. The criteria for concrete anchors is that " minimum thread engagement must be such that the outside face of the nut is flush with the last thread of the bolt."
The criteria for threaded fasteners (bolts in flanged connections) is "when installed conditions will not permit the engagement of two (2) full threads beyond the nut, then as a minimum, all of the chaefered end, if any, of the bolt or stud must protrude beyond the face of the nut."
(b) To resolve this issue GPC developed guidelines and prepared checklists l
for a nut / bolt thread engagement walkdown of VEGP safety-related l
mechanical equipment and trained the inspectors on the criteria. A representative sampling population of mechanical connections (flanges) was based on an initial population of 8671 isometric drawings, from which a random sample of 200 drawings was selected. A total of 65 flanges was used in the walkdown. These 65 flanges constitute a population of 801 nut / bolt (or nut / threaded rod) engagements, which is sufficiently large to draw valid statistical inferences about the untested population.
2 The walkdown checklists included mechanical connection (flange) description and location information. During the walkdown, inspectors recorded nut / bolt thread engagement data for each flange examined. When a connection was determined inaccessible (e.g. covered with insulation),
the inspectors were provided with a replacement walkdown checklist from the original random sample chosen.
i I
I i
k 4
- _ _~
._ -._ _, ~,_.
O.
All 801 nut / bolt combinations were found to comply with the VEGP thread engagement criteria. The sampling data were statistically analyzed and, concluded that more than 95 percent of the thread engagements in the total confidence level greater than 95 percent. This meets the Vogtle acceptance criteria for a randomly sampled population and meets the commonly used industry acceptance criteria.
(c) To prevent future occurrences GPC has developed Maintenance Procedure 25241-C entitled " Torquing" which incorporates the requirements of nut / bolt thread engagement for safety-related mechanical equipment. This procedure will be referenced and used during maintenance activities.
Generic Issue 3:
Confirm that 100-hour testing of all deep draft pumps is complete before fuel load.
GPC Response All deep draft pumps covered by GPC's response to IE Bulletin 79-15 will receive.100 hour0.00116 days <br />0.0278 hours <br />1.653439e-4 weeks <br />3.805e-5 months <br /> testing as previously committed. The only pumps remaining to be tested are the two NSCW transfer pumps,1-1202-P4-007 and 008. -These pumps are scheduled to complete this testing by November 14, 1986.
Generic Issue 4: Confirm that all active NSSS and BOP pumps and valves are correctly identified in the FSAR.
GPC Response: FSAR Tables 3.9.B.3-8 and 3.9.N.3-1 for BOP and NSSS active pumps, were revised in Amendment 23.
FSAR Tables 3.9.B.3-9 and 3.9.N.3-2 for BOP and NSSS active valves, were revised in Amendment 25. The active pump and valve tables are now complete and accurate.
Generic Issue 5: Confirm that all preservice tests for safety-related pumps and valves, that are required before fuel load, have been completed.
GPC Response: Georgia Power Company will provide a letter describing a detailed assessment of the status of work activities necessary to support fuel load. This letter will identify certain preoperational tests which will not be completed at the time of fuel loading, justifications for post-fuel load implementatioc, and a schedule for their completion. This letter is scheduled to be sent to the NRC on November 15, 1986.
Generic Issue 6:
Confirm that all safety-related pumps and valves are properly qualified and installed before fuel load.
GPC Response: Refer to cover letter.
0796V