ML20077A279
| ML20077A279 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 07/06/1983 |
| From: | Coffey J TENNESSEE VALLEY AUTHORITY |
| To: | NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| RO-50-259-83036, NUDOCS 8307220266 | |
| Download: ML20077A279 (2) | |
Text
i TRLRCOPY TO NRC ATL ANTn[Ju19$gg83 USNRC U. S. Nuclear Regulatory Commissior Region II r 3 Jill l'l All : 02 101 Marietta Street, BW Suite 3100 Atlanta, Georgia 30303 BFRO-50-259/83036 Reported under Technical Specification 6.7 2.a.1 Date of Occurrence: 7/05/83 Time of Occurrence: 0930 hours0.0108 days <br />0.258 hours <br />0.00154 weeks <br />3.53865e-4 months <br /> Unit 1 Technical Specification Involved: 2.2.A Conditions Prior to Occurrence Unit 1 shutdown for refueling; unit 2 at 110 We, and unit 3 at 1,034 We. -
Identification end Descriotion of Cecurrence Through verbal' notification, we have received data indicating that seven of 13 two-stage Target Rock relief valves tested at Wyle Laboratories for as-found set pressure initially failed to lift within the allowable range.
Tabulated below are valve serial numbers, set pressures, as-found set pressures, and percent deviation for the first lift.
Valve Serial Number Set Pressure As-Found Percent Deviation 1060 1105 ill 1135 27 1070 1105 111 1156 4.6 1084 1105 111 1128 2.1 1068 1125 ill ~
1137 1.07 1079 1115 111 1136 1.9 1075 1115 111 1016
-9.8 1027 1115 111 1158 2.9 The total average deviation is 2.54 percent.
Annarent Cause of Occurrence As stated in previous LERs (BFRO-50-260/8227, -259/8125, -296/8174), the cause is being evaluated with the manufacturer.
N/C 8307220266 830706 PDR ADOCK 05000259 f
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TELECOPY TO NRC July 6, 1983 BFRO-50-259/83036 (Continued)'
Other Related Events
Reference:
BFRO-50-260-8227, -296/8054, -259/8125, -296/8174.
The evaluations performed in the referenced LERs remain valid in that this problem does not result in an overexposure condition of reactor vessel piping nor_ does it result in any appreciable increase in MCPR operating limit.
Previous calculations performed by the General Electric Company indicated that for the previous unit 1 operating cycle, a total average deviation in relief valve setpoint of 5 0 percent could have existed with not significant effect on nuclear safety.
Corrective Action Taken or Planned These seven valves will be reset, and retested prior to installation.
l.
j A. Coff l
cting Power Plant Superintendent l
Browns Ferry Nuclear Plant I
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