ML18005A637

LER 88-026-00:on 880831,cracking of Insulation on Wires & on Terminal Blocks in Top Works Portion of Valves Noted.On 880909 Concluded Valves Inside Containment Not Qualified for Harsh Environ Following Postulated accident.W/881006 Ltr

ML18005A637
Person / Time
Site:	Harris
Issue date:	10/06/1988
From:	Howe A, Watson R CAROLINA POWER & LIGHT CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
HO-880204-(O), LER-88-026, LER-88-26, NUDOCS 8810120264
Download: ML18005A637 (6)

Text

ACCELERATED D RIBUTION DEMONS ATION'YSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)ACCESSION NBR:8810120264 DOC.DATE: 88/10/06 NOTARIZED:

NO FACIL:50-400 Shearon Harris Nuclear Power Plant, Unit 1, Carolina AUTH.NAME AUTHOR AFFILIATION HOWE,A.J.Carolina Power&Light Co.WATSON,R.A.

Carolina Power&Light Co.RECIP.NAME RECIPIENT AFFILIATION DOCKET 05000400 R I~D 05000400 S A NOTES:Application for permit renewal filed.,';'OPIES LTTR ENCL 1 1 RECIPIENT ID CODE/NAME PD2-1 LA BUCKLEY,B COPIES LTTR ENCL 1 1 1 1'ECIPIENT'D CODE/NAME PD2-1 PD

SUBJECT:

LER 88-026-00:on 880909,equipment qualification deficiency in target rock solenoid valves resulting in valve failure.'/8 ltr.DISTRIBUTION CODE-IE22D COPIES RECEIVED-LTR ENCL SIZE: TITLE: 50.73 Licensee Event Report (LER), Incident Rpt, etc.INTERNAL: ACRS MICHELSON ACRS WYLIE AEOD/DSP/NAS AEOD/DSP/TPAB DEDRO NRR/DEST/CEB SH NRR/DEST/ICSB 7 NRR/DEST/MTB 9H NRR/DEST/RSB 8E NRR/DLPQ/HFB 10 NRR/DOEA/EAB 11 NRR/DREP/RPB 10 NUDOCS-ABSTRACT ,RES TELFORD,J RES/DSIR/EIB EXTERNAL: EG&G WILLIAMS, S H ST LOBBY WARD NRC PDR NSIC MAYS,G 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1.1 1 1 1 1 1 1 2 2 1, 1 1'1 1 1 4 4 1 1 1 1 1 1 ACRS MOELLER AEOD/DOA AEOD/DSP/ROAB ARM/DCTS/DAB NRR/DEST/ADS 7E NRR/DEST/ESB BD NRR/DEST/MEB 9H NRR/DEST/PSB 8D NRR/DEST/SGB 8D NRR/DLPQ/QAB 10 NRR/DREP/RAB 10 NRR/DRIS/SIB 9A~G~IX@02 RES/DSIR DEPY RGN2 FILE 01 FORD BLDG HOY,A LPDR.'NSIC HARRIS,J 2 2 1 1 2 2 1 1 1 0 1 1 1 1 1 1 1 1 1 1 1 1 1 f 1 1 1 1 11 1 1 1 1 1 9 S R'TOTAL NUMBER OF COPIES REQUIRED: LTTR 46 ENCL 45 NRC Form 355 (943)LICENSEE EVENT REPORT HLER)U.S.NUCLEAR REOULATORY COMMISSION APPROVED OMB NO.3)500)04 EXPIRES: 5/31/SS FACILITY NAME (1)SHEARON HARRIS NUCLEAR POWER PLANT-UNIT ONE DOCKET NUMBER (2)PA E 0 5 0 0 0 4 0 0 1 OF 0 4 EQUIPMENT QUALIFICATION DEFICIENCY IN TARGET ROCK SOLENOID VALVES RESULTING IN POTENTIAL VALVE FAILURE DURING ACCIDENT EVENT DATE (5)LER NUMBER LS)AEPOAT DATE (7)OTHER FACILITIES INVOLVED IS)MONTH DAY YEAR YEAR??c)SSOUSNTIAL NUMBER yw.: ttevtcx}N fry NUMBER MONTH OAY YEAR FACILITY NAMES DOCKET NUMBER(S)0 5 0 0 0 09 09 8 8 8 8 0 2 6 0 0 1 0 0 6 8 8 0 5 0 0 0 OPE RATINO MODE (9)POWER LEVEL uo)0 0 0 o}gi QM Y@Q~g x 20A02(bl 20AOS(s)(1)(I)20 e05(~)(1)(el 20.405(~I 0)(III)20AOS(s I (1)(Ir)20.e05(s)(1)(e)20AOS(c)SOM(c)(1)50.35(cl(2) 50.73(s)(2)(I)50.73(el(2)

(5)50.73(s)(2)(III)50.734)(2)(4)X 50.73(s)(2)(r) 50.73 4)(2)(re)50.73(sl(2)(riIIHA) 50.73(sl(2)(rIII)(B)50.73(sl (2)(x)LICENSEE CONTACT FOR THIS LER (12)0 THE REOUIREMENTS OF 10 CFA (): fChecb onr ormorr of the folio}ylnpl (11 THIS AEPORT IS SUBMITTED PURSUANT T 73.71(S)73.71(cl OTHER ISpetlfy In rebtaett below rnd ln Trit, HRC Form 3PIIAI NAME Andrew J.Howe"-Senior Engineer TELFPHONE NUMBER AREA CODE 9 19 362-2 719 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13)CAUSE SYSTEM COMPONENT MANUFAC.TURER EPORTABLE TO NPADS CAUSE SYSTEM COMPONENT MANUFAC.TUAER EPORTABLE TO NPADS o}}s;B K N B A B IS V V TV T 020 T 2 0 Y SUPPLEMENTAL REPORT EXPECTED (Ie)YES (If yrt, complrte EXPECTED SUBSIISSIDH DATEI NO ABSTRACT ILlmlt to Ie00 tpecre, I r., epproilmetely flftrrn tlnpleepecr typerwlnrn Ilnetl (15)ABSTRACT: EXPECTED SUBMISSION DATE 05)MONTH DAY YEAR During routine replacement of solenoid coils on Target Rock valves on August 31, 1988, during a refueling outage, plant personnel noted cracking of ins'ulation on wires and on the terminal blocks in the top works portion of the valves.The valves were located on sampling lines and on the Reactor Coolant System head vent system inside containment, and on other safety-related systems outside containment. An engineering evaluation concluded on September 9 that the valves inside containment were not qualified for harsh environment following a postulated accident.This situation arose due to fabrication problems and vendor modifications using parts which had not been tested or evaluated to ensure qualification. The valves are not required to be opeiable during shutdown conditions. Replacement of the unqualified top works of the affected valves inside contain'ment was'ccomplished prior to returning the plant to service.SS10120264 881006 PDR ADOCK 05000400 S PDC NRC Form 355 (Be)3) NRC form 3SEA (94(3l LICENSEE EVENT REPORT ILER)TEXT CONTINUATION U.S.NUCLEAR REGULATORY COMMISSION APPROVEO OMB NO.3(50&(04 EXPIRES: 5/3(/SS fACILITY NAME (ll OOCKET NUMBER (31 LER NUMBER (5)PACE (31 SHEARON HARRIS NUCLEAR POWER PLANT-UNIT ONE TEXT I/f more Z>>oe N reevfrd.eee//r/o/o//Y/IC Fone 3/E(AS/((Tl INITIAL CONDITIONS: o s o o o40 0 8 8 026 00 VE*R rFIK SEOUENTIAL r'N REVISION NVM ER r NVMSEA 02pF 0 4 The plant was in Mode 6 during a refueling outage at the time of discovery of the condition. EVENT DESCRIPTION: During normal maintenance replacement of solenoid coils in environmentally qualified (EQ)valves per EQ requirements on August 31, 1988, discrepancies were noted in the top works portion of several valves.Specifically, (1)cracking of the reed switch lead wire insulation at the switch potting, and (2)hairline cracking.and breakage of terminal blocks at the termination points of jumper wires were observed in the field.Engineering personnel were unable to determine traceability between reed switch lead wires and terminal blocks that were tested by the manufacturer versus what was supplied with the valves.The valves in question are manufactured by Target Rock Corporation, model numbers as follows: 79Q-5, 79Q-9, 79Q-14, 79Q-17, 79Q-18, 79Q-19, 79Q-21, 79Q-22, 79Q-25, 79Q-26, and 86Z545-001. They are installed inside reactor containment as containment isolation valves for the sampling system (EIIS:KN:ISV) and as Reactor Coolant System (RCS)vent valves (EIIS:AB:VTV). Other applications of these valves exist in safety.systems located in mild environments, and are not impacted by the deficiencies'n September 9, an engineering review concluded that the valves as installed were not qualified for a harsh environment, and that a potential failure mode existed during accident conditions which could result in the inability of the affected valves to perform their intended safety function.None of the valves identified were required to be operable at the time of discovery of the deficiency. The valves were declared inoperable, and, work requests were initiated to replace the top works portion of the valves with fully qualified replacements. ANALYSIS OF FAILURE MODE: Based on the deficiency discovered, two failure modes are postulated: (1)short to ground of.exposed wires at the reed switch, and (2)wire to wire short at the reed switch.In case 1, the failure could result in a dual position indication, or an overcurrent condition whi:ch blows the control power fuse, or both.The valves would fail closed upon loss of control power.NRC FORM SSOA (9431*U.S GPO.1955 0.524 538/455 NRC Form 388A$83 l LICENSEE EVENT REPORT (LER)TEXT CONTINUATION U.S, NUCLEAR REOULATORY COMMISSION APPROVEO OMS NO.3150MIOO EXPIRES: 8/31/88 FACILITY NAME 111 SHEARON HARRIS NUCLEAR POWER PLANT-UNIT ONE OOCKET NUMSER 12l YE A II LER NUMBER 151 SEQUENTIAL NVM OR II 5 V IO IO N NVMOOII~AOE 13)osooo400 TEXT/1/more ioooe*reeMONE Moo o/R/N5eoo/NRC Fonrl 3///A'o/1171 ANALYSIS OF FAILURE MODE: (continued) 8 8 026 00 03 OF 0 4 In case 2, the failure could also result in a dual position indication, or could cause inadvertent opening of the valve, or both.The, valves would still close upon receipt of a containment isolation signal since this signal interrupts control power to the valve, or the valve could be closed by deenergizing the control power to the valve.CAUSE: The cause of the valve inoperability is a fabrication process deficiency. The potting compound used in the reed switch caused the deterioration of the lead~ires and subsequent cracking.The cracks observed in the terminal blocks at the termination points of the jumper wires probably occurred while tensioning the fastener.The discrepancies noted in documentation of test results for the valves was caused by the vendor modifying the valve with parts which were not subsequently tested or evaluated as acceptable. SAFETY ASSESSMENT: There are three accident mitigation functions affected by this deficiency'. containment isolation of sampling lines, containment hydrogen sampling capability, and RCS venting capability. The containment isolation function of the valves would have been met during an accident because the isolation signal interrupts control power to the valves, all of which close on loss of control power.A dual position indication could have led the operator to believe the valves were still open, and he may then have taken unnecessary actions to manually close the valves.The hydrogen sampling capability following an accident provides data to determine whether hydrogen removal via the electric hydrogen recombiners-is required, or whether the hydrogen purge system should be placed in service if the recombiners were ineffective. The unavailability of this data would most likely have resulted in placing these systems in service to ensure removal of any excess hydrogen until other means of sampling the containment atmosphere were established. The potential spurious opening of the RCS head vent valves is not possible since the control.power to these valves is maintained disconnected at the control switch in the main control room.The RCS vent system is not assumed to operate for any accident analyzed in the Final Safety Analysis Report, but is provided to remove any potential noncondensible gasses from the RCS which may accumulate at high points in the RCS and potential'ly inhibit natural circulation cooling following a small break loss of coolant accident.Only one safety train of.thi's system is required operable by Technical Specifications. \NIIC FOIIM 3OOA 18831~U.S GPO 1088.0.82i 538/455 NRC Form 3SSA (94I3)LICENSEE EVENT REPORT ILER)TEXT CONTINUATION U.S, NUCLEAR REGULATORY COMMISSION APPROVED OMS NO, 3150&104 EXPIRES: 8/31/88 FACILITY NAME ul SHEARON HARRIS NUCL'EAR POWER PLANT-UNIT ONE DOCKET NUMBER 12)YEAR Pgr.'EQUENTIAL NVM Eh LER NUMBER 151 REvrsroN NVM Sh PAGE 13)TEXl'//more Seeco/I eehr4kerE rroe///Ooro///RC fcnrr 3854 8/I ITl SAFETY ASSESSMENT: (continued) 0 5 0 0 0 4 0 8 8 026 00 04 oF 0 4 This event is reportable under 10 CFR 50.73 (a)(2)(v)as a condition that could have prevented the fulfillment of a safety function of a system which mitigates the consequences of accidents. A review for reportability under 10 CFR 21 has concluded that no substantial safety hazard was introduced by this condition, and therefore the reporting requirements of this part are not applicable. CORRECTIVE ACTIONS: Replacement of the unqualified top works of the affected valves with fully qualified parts was accomplished prior to returning the valves to operable status.NhC PO/IM SSSA IBS31 e U.S GPO.1988-0.824 538/455 Carolina Power 8 Light Company HARRIS NUCLEAR PROJECT P.O.Box 165 New Hill, NC 27562 OCT 0 6 1988 Pile Number'SHF/10-13510C Letter Number'HO-880204 (0)U.S.Nuclear Regulatory Commission ATTN: NRC Document Control Desk Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NO~50-400 LICENSE NO.NPF-63 LICENSEE EVENT REPORT 88-026"00 Gentlemen: In accordance with Title 10 to the Code of Federal Regulations, the enclosed Licensee Event Report is submitted. This report fulfills the requirement for a written report within thirty (30)days of a reportable occurrence and is in accordance with the format set forth in NUREG-1022, September 1983.Very truly yours, AJH:tbb Enclosure R.A.Watson Vice President Harris Nuclear Project cc: Mr.M.L.Ernst Mr.B.C.Buckley (NRR)Mr.W.H.Bradford (NRC-SHNPP)MEM/LER-88-026/1/0<1}}