ML20084D888

AO 50-237/75-34:on 750513,drywell Equipment Drain Sump Pump Discharge Valve AO-2001-5 Failed to Close.Possibly Caused by Dirt on Solenoid Diaphragms.Valve Disassembled & Cleaned & Electric Conduit Insulation Repaired

ML20084D888
Person / Time
Site:	Dresden
Issue date:	05/21/1975
From:	Stephenson B COMMONWEALTH EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
318-75, 5676, AO-50-237-75-34, NUDOCS 8304120646
Download: ML20084D888 (3)

Text

'

. 1 Com wxith Edison

• M *;*. one ri ihonal Plaza. Chicaao, liknois G.Q Address Hoply to: Post Office Box 767 -

Chicago, Illinois 60690 BBS Ltr. #318-75 - , Dresden nuclear Power Station R.11. #1 ,

Morria, 1111noio 60450 May 21, 1975 Opp T

N>,.

Mr. James G. Keppler, Regional Director Directorate of Regulatory Operation-Region III U. S. Nuclear Regulatory Com:niosion , , ,

g 799 Roorevelt Road Glen Ellyn, Illinois 60137 SU.BJECT: REFORT OF I.D:0RIML OCCURRF2 CE PFR SECTIO!I 6.6.A 0F THE TE10!ICAL SPECIFICATIC::3 DHL.' ELL EC.UIEG2IT DItAIN SlFP DISCP.,UlGE VALVE AO-2001-5 FAILURE

References:

1) Regulatory Guide 1.16 Rev. 1 Appendix A

2) Motification of Region III of U. S. Muelcar Regulatory Corra:ission Telephone: Mr. Johncon, 0955 hours0.0111 days <br />0.265 hours <br />0.00158 weeks <br />3.633775e-4 months <br /> on May 14, 1975 Telegram: Mr. Keppler, 1115 hours0.0129 days <br />0.31 hours <br />0.00184 weeks <br />4.242575e-4 months <br /> on !*.ay 14, 1975 l

3) Drawing Number: P & ID M-39 Report Number: 50-237/75-24

! Report Date: May 21, 1975 j Occurrence Date: May 13, 1975 Facility: Dresden Nuclear Power Station, Morris, 1111noin IDZITIFICATION OF OCC1GRC CE l

The drywell equi ment drain sump pump discharge valve A0-2001-5 failed to cloco.

1 CONDITIONS PRIOR TO OCCURRE:!CE At the time of the occurrence, the unit was in a refueling outage with the reactor modo awitch in the shutdown pocition.

i DFECRIPPION OF OCCURRF2:CE 1000 hours0.0116 days <br />0.278 hours <br />0.00165 weeks <br />3.805e-4 months <br /> on May 13, 1975, while performing primary containment icolation val.ve timing curveillance, the drywell equiment drain sump pump di acharge valve A0-2001-5 failed to closo as indicated by the valve position indicator 8304120646 750521 PDR ADDCK 05000237 S PDR t* W ' '"'

3

Mr. James G. Keppl+T ('T May 21, 1975 U V lights in the control room. The initial operator action was to verify that valve A0-2001-6, which is in series with valve A0-2001-5, was operable and did close when given the signal.

DESIGNATIO:! 0F APPARFl:T CAUSE GP CUlulENCE (Unusual Service Conditions)

At 2320 hours0.0269 days <br />0.644 hours <br />0.00384 weeks <br />8.8276e-4 months <br /> on the came day, the maintenance department requested that another attempt be made to cycle valve A0-2001-5 prior to any repairs. The valve was cycled three times without failing. The following morning, the valve was again successib11y cycled ten times.

Incpection of the valve chowed an exccocive amount of metal filings on the solenoid control valve and a section of inculation missing from the electribal conduit Icading to the valvo. The A0-2001-5 valve is phycically located directly underneath penetration X-123 This penetration recently had the bellows replaced. Conduit insulation damage and the accumulation of metal filings apparently occurred at that time. It is believed that a thin film of dirt on the solenoid diaphragms temporarily interfered with normal operation cinco no electrical problem could be found. .

/ DIALYSIS OF OCCUR:lENCE Unit--2 was shut down for refueling at the time of the malfunction and primary containment integrity was not required. Had containment integrity been required, valve A0-2001-6 was operable, having a through leakage rate well within Technical Specification limits as demonstrated by a recent local leak rate test. Therefore ,

the health c.d safctj vf U.e pimd, persumel and the puolle were not jeopardized in any way by the incident.

C0!UtECTIVE ACTION The solenoid control valve was disassembled and cleaned, and the electric conduit inculation was repaired. The valve was again checked for operability and placed back in service at 0300 hours0.00347 days <br />0.0833 hours <br />4.960317e-4 weeks <br />1.1415e-4 months <br /> on I".ay 17, 1975 FAILURE DATA A review of the history of the drywell equiptent drain cump pump icolation valves for Units 2 & 3 chows only one uimilar occurrence. On March 9, 1974 the same valve failed to close completely. Thic failure was attributed to dirt in the solenoid control valve.

Valve A0-2001-5 is a 3" 150 lb. cast steel cate valve with a 6" diameter cylinder manufactured by Crane Co. , catalog number 47 x R.

g ,B. B. Stephencon Superintendent BBS: cmp l

File /lIIC

NEU' orcta cf Regulc.6ory Operctions Tel^-"*' ied Dato - 7~/ b O gion III V3S' Nuclent Regulatory Commi'azion s* CE /I*97 799' Roosevelt Road EC _ -

Clen Ellyn, IL 60137 37 _ m) cc:

Bernard C. Rusche, Director-Directorate of Licensing U.S~.. Nuclear Regulatory Commission Washington, D.C. 20555

SUBJECT:

DPFr__/f . Dresden. Nuclear Power Station, Unit 1- _.

Thic. will. confim a conversation. with /42 ONdJo C -- of your office at CRff hrs this data concerning p;Frav/c C# d#/M'r7 L mAusvr fus,p /) gyp f.);.gctj,. dedo /&ts /k2 2cc/~C' To G L O Sc.r &/g G}&qTc?2l.Jf //// L'r .7A*!'"W /thM /SNA'f SE A% cro,e ams /tv Ga .D/u,aw.s Govou sr .we .wer dus

/hsre, &nma.we.vr sm.s . 6er Amn2 Ornm VM AJ4"E "'

4/cs b.w m sr>Jre o C A w ] & ti 77/r //tMi6 NkL A N "M

72) Gner Vp

,3 d

u' I

{ --)(r f

• e A;eaa;;;;.;; A . .;.;da *As Aa;. a A A A A Ae A Aa A;;

To Call: E. B. StePhenson, Superintendent GE 858-2660x16.(auto) Dresden. Nuclear Power Station.

DC' 1-301-492-7617 (auto) - m 6 Coenonwealth: Edison. Company hv - 815-942+4449/4321 E.R. fl Station Dist: Originator (copy)

• _ Incident File (copy) . Telenhana- 815094202920/29*11r212