ML18005A637

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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 Duke Energy icon.png
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 DOCKET FACIL:50-400 Shearon Harris Nuclear Power Plant, Unit 1, Carolina 05000400 AUTH. NAME AUTHOR AFFILIATION HOWE,A.J. Carolina Power & Light Co.

WATSON,R.A. Carolina Power & Light Co.

RECIP.NAME RECIPIENT AFFILIATION

SUBJECT:

LER 88-026-00:on 880909,equipment qualification deficiency R in target rock solenoid valves resulting in valve failure.'/8 ltr. I DISTRIBUTION CODE- IE22D COPIES RECEIVED-LTR ENCL SIZE:

TITLE: 50.73 Licensee Event Report (LER), Incident Rpt, etc. ~

D NOTES:Application for permit renewal filed.,';'OPIES 05000400 S RECIPIENT COPIES 'ECIPIENT'D ID CODE/NAME LTTR ENCL CODE/NAME LTTR ENCL A PD2-1 LA 1 1 PD2-1 PD 1 1 BUCKLEY,B 1 1 INTERNAL: ACRS MICHELSON 1 1 ACRS MOELLER 2 2 ACRS WYLIE 1 1 AEOD/DOA 1 1 9 AEOD/DSP/NAS 1 1 AEOD/DSP/ROAB 2 2 AEOD/DSP/TPAB 1 1 ARM/DCTS/DAB 1 1 S DEDRO 1 1 NRR/DEST/ADS 7E 1 0 NRR/DEST/CEB SH 1 1 NRR/DEST/ESB BD 1 1 NRR/DEST/ICSB 7 1 1 NRR/DEST/MEB 9H 1 1 NRR/DEST/MTB 9H 1. 1 NRR/DEST/PSB 8D 1 1 NRR/DEST/RSB 8E 1 1 NRR/DEST/SGB 8D 1 1 NRR/DLPQ/HFB 10 1 1 NRR/DLPQ/QAB 10 1 1 NRR/DOEA/EAB 11 1 1 NRR/DREP/RAB 10 1 1 NRR/DREP/RPB 10 2 2 NRR/DRIS/SIB 9A 1 1 1 '1 NUDOCS-ABSTRACT

,RES TELFORD,J 1, 1 ~G~IX@

RES/DSIR DEPY 02 1 1

f 1

1' RES/DSIR/EIB 1 1 RGN2 FILE 01 EXTERNAL: EG&G WILLIAMS,S 4 4 FORD BLDG HOY,A 1 1 R'

H ST LOBBY WARD 1 1 LPDR . 1 1 NRC PDR 1 1 'NSIC HARRIS,J 1 1 NSIC MAYS,G 1 1 TOTAL NUMBER OF COPIES REQUIRED: LTTR 46 ENCL 45

NRC Form 355 U.S. NUCLEAR REOULATORY COMMISSION (943)

APPROVED OMB NO. 3)500)04 LICENSEE EVENT REPORT HLER) EXPIRES: 5/31/SS FACILITY NAME (1) DOCKET NUMBER (2) PA E SHEARON HARRIS NUCLEAR POWER PLANT UNIT ONE 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 yw.: ttevtcx}N MONTH OAY YEAR FACILITYNAMES DOCKET NUMBER(S)

NUMBER fry NUMBER 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 THIS AEPORT IS SUBMITTED PURSUANT T0 THE REOUIREMENTS OF 10 CFA (): fChecb onr ormorr of the folio}ylnpl (11 MODE (9) 20A02(bl 20AOS(c) 50.734) (2)(4) 73.71(S)

POWER 20AOS(s) (1)(I) SOM(c) (1) X 50.73(s)(2)(r) 73.71(cl LEVEL uo) 0 0 0 20 e05( ~ )(1)(el 50.35(cl(2) 50.73 4) (2) (re) OTHER ISpetlfy In rebtaett o} gi QM below rnd ln Trit, HRC Form Y@Q~g 20.405( ~ I 0) (III) 50.73(s) (2) (I) 50.73(sl(2)(riIIHA) 3PIIAI 20AOS(s I (1)(Ir) 50.73(el(2) (5) 50.73(sl(2) (rIII)(B) x 20.e05(s) (1)(e) 50.73(s) (2) (III) 50.73(sl (2) (x)

LICENSEE CONTACT FOR THIS LER (12)

NAME TELFPHONE NUMBER AREA CODE Andrew J. Howe"- Senior Engineer 9 19 362 2 719 COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT (13) o}} CAUSE SYSTEM COMPONENT MANUFAC. EPORTABLE SYSTEM COMPONENT MANUFAC. EPORTABLE s; TURER TO NPADS CAUSE TUAER TO NPADS B K N IS V T 020 B A B V TV T 2 0 Y SUPPLEMENTAL REPORT EXPECTED (Ie) MONTH DAY YEAR EXPECTED SUBMISSION DATE 05) YES (If yrt, complrte EXPECTED SUBSIISSIDH DATEI NO ABSTRACT ILlmlt to Ie00 tpecre, I r., epproilmetely flftrrn tlnpleepecr typerwlnrn Ilnetl (15) ABSTRACT: 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 U.S. NUCLEAR REGULATORY COMMISSION (94(3l LICENSEE EVENT REPORT ILER) TEXT CONTINUATION APPROVEO OMB NO. 3(50&(04 EXPIRES: 5/3(/SS fACILITYNAME (ll OOCKET NUMBER (31 LER NUMBER (5) PACE (31 VE*R rFIK SEOUENTIAL r 'N REVISION NVM ER r NVMSEA SHEARON HARRIS NUCLEAR POWER PLANT UNIT ONE o s o o o40 0 8 8 026 00 02pF 0 4 TEXT I/fmore Z>>oe N reevfrd. eee //r/o/o/ /Y/IC Fone 3/E(AS/ ((Tl INITIAL CONDITIONS: 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 *U.S GPO.1955 0.524 538/455 (9431

NRC Form 388A U.S, NUCLEAR REOULATORY COMMISSION

$ 83 l LICENSEE EVENT REPORT (LER) TEXT CONTINUATION                                APPROVEO OMS NO. 3150MIOO EXPIRES: 8/31/88 FACILITY NAME 111                                                      OOCKET NUMSER 12l         LER NUMBER  151                      ~ AOE 13)

II5 V IO IO N SHEARON HARRIS NUCLEAR POWER YE A II SEQUENTIAL NVM OR NVMOOII PLANT UNIT ONE osooo400 8 8 026 00 03 OF 0 4 TEXT /1/more ioooe*reeMONE Moo o/R/N5eoo/NRC Fonrl 3///A'o/1171 ANALYSIS OF FAILURE MODE: (continued) 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 ~ U.S GPO 1088.0.82i 538/455 18831

NRC Form 3SSA U.S, NUCLEAR REGULATORY COMMISSION (94I3) LICENSEE EVENT REPORT ILER) TEXT CONTINUATION APPROVED OMS NO, 3150&104 EXPIRES: 8/31/88 FACILITY NAME ul DOCKET NUMBER 12) LER NUMBER 151 PAGE 13) YEAR Pgr.'EQUENTIAL REvrsroN NVM Eh NVM Sh SHEARON HARRIS NUCL'EAR POWER PLANT UNIT ONE 0 5 0 0 0 4 0 8 8 026 00 04 oF 0 4 TEXl'//more Seeco /I eehr4kerE rroe ///Ooro///RC fcnrr 3854 8/ I ITl SAFETY ASSESSMENT: (continued) 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 e U.S GPO.1988-0.824 538/455 IBS31

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, R. A. Watson Vice President Harris Nuclear Project AJH:tbb Enclosure cc: Mr. M. L. Ernst Mr. B. C. Buckley (NRR) Mr. W. H. Bradford (NRC SHNPP) MEM/LER-88-026/1/0<1}}