ML20235Z032
| ML20235Z032 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 02/27/1989 |
| From: | Bradham O SOUTH CAROLINA ELECTRIC & GAS CO. |
| To: | Ernst M NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| IEB-85-003, IEB-85-3, NUDOCS 8903150054 | |
| Download: ML20235Z032 (4) | |
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South Ccrtlins Electric & Gas Camp:ny'
. ollie S. Bradh;m
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P.O. Box 88 Vice President Jinkinsvilla. SC 29065 Nuclear Operttions (803) 3454040 SCE&G'
' February 27, 1989 g g A9 U Mr. Malcolm L. Ernst Regional Administrator.
-U. S. Nuclear Regulatory. Commission Suite 2900 101 Marietta Street, NW Atlanta, Georgia 30323
Subject:
V. C. Summer Nuclear Station Docket No. 50/395 Operating License No. NPF-12 IE Bulletin 85-03 Completion Report
Dear Mr. Ernst:
~ Attached is the South Carolina Elr;tric & Gas Company Completion Report for-
.i the seventeen valves remaining in the IEB 85-03 program, " Motor Operated Valves Common Mode failures During Plant Transients Due to Improper Switch Settings." This report documents the completion of differential-pressure testing as required by action (c) of the Bulletin.
Should you have any questions, please call at your convenience.
Very truly yours, O. S. Bradham MDB/0SB: led x
Attachment c:
D. A. Nauman/J. G. Connelly, Jr./0. W. Dixon, Jr./T. C. Nichols, Jr.
E. C. Roberts W. A. Williams, Jr.
G. O. Percival General Managers R. L. Prevatte J. J. Hayes Jr.
J. B. Knotts, Jr.
C. A. Price /R. M. Campbell, Jr.
M. D. Blue R. B. Clary M. R. Hazel J. R. Proper NSRC l
K. E. Nodland RTS (850003) l J. C. Snelson File (815.02) gQ g&.h W C
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A IEB 85-03 MOTOR OPERATED VALVE COMMON MODE FAILURES DURING PLANT TRANSIENTS DUE TO IMPROPER SWITCH SETTINGS SOUTH CAROLINA ELECTRIC & GAS COMPANY COMPLETION REPORT
1 cI..
Introduction'-
South Carolina Electric & Gas' Company (SCE&G) has completed the required; action described in-IEB'85-03 for the valves-identified in our letter dated November 20,f1987. Our program at the Virgil C.~ Summer Nuclear. Station.
utilized Motor Operated Valve Analysis:and Test System (M0 VATS) signature i
Lanalysis in combination with vendor test data and differential pressure.
testing. The plant procedure for obtaining M0 VATS signatures was.used for each identified valve pertaining to IEB.85-03.
-II.
Program Description The testing methodology consisted of obtaining the signature analysis results,' documenting discrepancies in operator thrust values through our nonconformance program, and providing engineering evaluation of these-discrepancies. The affected valves were adjusted in order to. meet'the particular valve's thrust requirements for design basis function.
Our program consisted of the.following procedures:
1.
Stem thrust data was obtained'from the appropriate vendors. Torque switch settings were not used as a basis for valve operability' confirmation due to our past experience with torque switch and thrust value comparisons. Our. program presently uses thrust values only because torque switch settings are not reliable indicators.
2.
Any valve packing replacement or adjustment was performed per, plant procedures.
3.
M0 VATS signature analysis was then performed for the.specified valves.
Stem thrust values,' torque bypass settings, and limit switch settings were then verified.
~
4.
All seventeen valves were stroke tested against the pressure differential listed in Section III, " Summary of Results of Program."
Valves tested at partial differential pressures are considered to meet the IEB requirements because-the valves were tested at pressures very close to accident pressure and the as-left thrust values were higher than calculated minimum thrust values.
Valve undervoltage considerations have been reviewed for the seventeen.
-valves. Calculations or testing at design basis undervoltage conditions have been performed which demonstrated valve functional performance. The acceptable results are documented in SCE&G internal memoranda.
SCE&G will continue to maintain all IEB identified valves through our existing plant preventive maintenance program.
a III.
Summary of Results of Program Testing and evaluation of the seventeen valves listed below was conducted in accordance with an Electrical Maintenance Procedure. Acceptance criteria for thrust values are contained in EMP 445.008 "Limitorque Valve Data." The evaluations, which considered design basis operability requirements, resulted in design basis acceptance of all seventeen valves.
Tested Differential Valve Pressure (PSIG)
XVG8130A 38 XVG8130B 38 XVG8131A 38 XVG8131B 38 XVG8106 2200 XVT8109A 2300 XVT8109B 2200 XVT8109C 2300 XVG8132A 2500 XVG8132B 2250 XVG8133A 2200 XVG8133B 2450 XVG8884 2650 XVG8885 2650 XVG8886 2650 XVG2802A 1095 XVG2802B 1095 IV.
Records and Procedures The results of the testing performed during the fourth refueling outage are maintained in the Plant Records System. This information is recorded on Preventive Maintenance Task Sheets (PMTS) or Maintenance Work Requests (MWR). Valve Stroke Testing was performed under Preventive Test Procedure (PTP) 170.002, " Stroke Testing Motor Operated Valves."
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