ML17338B268

LER 79-001/03L-0 on 790118:valve V-14-35 Failed to Open Completely During Routine Isolation Condenser Valve Operability Test.Caused by Dirty Torque Limit Switch Contacts,Which Were Subsequently Cleaned & Burnished

ML17338B268
Person / Time
Site:	Oyster Creek
Issue date:	02/15/1979
From:	ROSS D A JERSEY CENTRAL POWER & LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML17338B267	List: ML17338B266 ML17338B268
References
LER-79-001-03L, LER-79-1-3L, NUDOCS 7902230119
Download: ML17338B268 (5)

Text

>NRC FORM 366 ,P-77)E EVENT REP Q1 tPLEASE PRINT OR TYPE ALL REQUIRED INFORMATION) 6 0 0 0 0 0 0 0 0 Q3 4 1 1 1 1 04~Qs LICENSE NUMBER 25 26 LICENSE TYPE 30 57 CAT 58 Qs02 1 Qs 74 75 REPORT DATE LICENSE ORT~h , CONTROL BLOCK: I~op1 1N J 0 C P 1 Q 7 8 9 LICENSEE CODE 14 15 CON'T~o>,",~Lpeo 5 0 0 0 Z 1 9 Q70 1 1 8 7 7 8 60 61 DOCKET NUMBER 68 69 EVENT DATE EVENT DESCRIPTION AND PROBABLE CONSEQUENCES Q10 On January 18, 1979, while performing a routine isolation condenser~O3~p4~os~OB~O7 valve operabil ity test, T.S.3.8.A was violated when valve V-14-35 fail-ed to open completely.

When the test initiating signal was applied, the valve opened approximately 104 and then stopped.Valve V-14-35 is D.C.motor operated and is fitted with a double torque.limit switch which is bypassed by a shorting switch during approximately the first IOC of valve travel.~o-s 7 8 80[OO~)8 SYSTEM CAUSE CAUSE COMP.VALVE CODE CODE SUBCODE COMPONENT CODE SUBCODE SUBCODE~s~0>>G 0>>~A073 3 A L v 0 3 8 Lxgp~xS 9 10 11 12 13 18 19 20 SEQUENTIAL OCCURRENCE REPORT REVISION LER]SO EVENT YEAR REPORT NO.CODE TYPE NO.Q17 REPoRT~79~~00 1~M~0 LiJ LJ LJ 21 22 23 24 26 27 28 29 30 31 32 ACTION FUTURE EFFECT SHUTDOWN ATTACHMENT NPRDX PRIME COMP.COMPONENT TAKEN ACTION ON PLANT METHOD HOURS Q22 SUBMITTED FORM SUB.SUPPLIER MANUFACTURER LB/073~X.QR~Zp>>~Zp>>O O O O V 023~V024~V023 L Z O O 023 33 34 35 36 37 40 41 42 43 44 47 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS 27 o The cause of this occurrence was dirty torque limit switch contacts 1~i 3~14 which created an opening in the motor circuit after approximately 100 valve travel.The contacts were cleaned and burnished and the valve test was successfully completed.

The use of an'ohm meter to check the torque limit switch contacts will be incorporated into the P.H.program.ACTIVITY CONTENT RELEASED OF RELEASE AMOUNT OF ACTIVITY 3 Z Q33~ZQ34 NA 7 8 9 10 11 44 PERSONNEL EXPOSURES NUMBER TYPE DESCRIPTION 7~00 0 03~ZQ33 7 8 9 11 12 13 PERSONNEL INJURIES NUMBER DESCRIPTION 41 3~OO O Q43 7 8 9 11 12 LOSS OF OR DAMAGE TO FACILITY 43 TYPE DESCRIPTION 9 Z Q42 8 9~10 PUB L I CITY ISSUED DESCRIPTION 4S KZ~V Q4" NeeklV news 8 9 10 45 NA NA NA D Iald A.Ross NAME OF PREPARER 7 8 9 FACILITY M3P METHOD OF STATUS 9P POWER OTHER STATUS~DISCOVERY~la G Q23~00 0 Q23 NA~Bp>>7 8 9 10 12 13~44 45 46"DISCOVERY DESCRIPTION Q32 Surveillance Test LOCATION OF RELEASE NA 80 80 80 80 VSOZZ30qq 80 80 NRC USE ONLY I 68 69 80'201-455-8784 PHONE:

I~+s T g 1.(1 Jersey Central Power&Ught Company Madison Avenue at Punch Bowl Road Morristown, New Jersey 07960 (201)455-8200 OYSTER CREEK NUCLEAR GENERATING STATION Forked River, New Jersey 08731 Licensee Event Report Reportable Occurrence No.50-219/79-1/3L"0 Report Date February 15, 1979 Occurrence Date.January 18, 1979 Identification of Occurrence Violation of the Technical Specifications, paragraph 3.8:A when valve V-14-35 failed to operate as required during a routine valve operability test.This event is considered.to be a reportable occurrence as defined in the Technical Specifications, paragraph 6.9.2.b.2.

Condit'ions Prior.to Occurrence The plant was in a shutdown condition for maintenance.

Plant parameters at the time of the occurrence were: Reactor pressure-145 psig Recirculation flow-3.1 x 104 gpm Stack Gas-90 ttCi/sec Description of Occurrence On Thursday, January 18, 1979, at approximately 1500 hours0.0174 days <br />0.417 hours <br />0.00248 weeks <br />5.7075e-4 months <br />, while performing the isolation condenser valve operability test, valve V-14-35 failed to open completely.

Upon aninitiation signal, valve V-14-35 opened approximately 100, and then stopped.Apparent Cause of Occurrence Component failure was the cause of this event.Valve V-14-35 is D.C.motor operated and is fitted with a double torque limit switch.Jersey Central Power Light Company is a Memper of the General Pu inc Utilities System Reportable Occurrence No.50-219/79"1/3L-0 February 15, 1979 Page 2 During approximately the first lOR of travel in the opening mode, the torque limit switch is bypassed by the use of a shorting switch because of the high torque required to unseat the valve.After 10'f travel, the torque limit switch controls valve travel.Upon failure of valve V-14-35, investigation revealed that the contacts on the torque limit switch were dirty;thus creating an opening in the motor circuit after approximately 10'f valve travel.Anal sis of Occurrence The safety significance of this event is considered to be minimal since during this period the"A" isolation condenser was available for operation.

If one isolation condenser is found to be inoperable, there is no immediate threat to the heat removal capability for the reactor and reactor operation.

The purpose of the isolation condenser is to depressurize the reactor and to remove reactor decay heat in the event that the main condenser is unavailable as a heat sink and heat removal systems which required AC power for operation are not available.

Corrective Action The torque limit switch contacts were cleaned with a suitable solvent type cleaner and burnishi'ng, tool.The use of an ohm meter to check the torque limit'switch contacts will be incorporated into the preventative maintenance program.Valve V-14-35 was then cycled three times successfully, meeting all the requirements of the isolation condenser valve operability test.Failure Data Manufacturer:

Limitorque Corporation Part No.SMB-00 Type SMB-2 I~<P ,t Vf