ML20086S417

AO-S1-74-04:on 740502,valve MOV-FW-151C Failed to Open When Required During Testing.Caused by Failure of Contact Block 3A-8.Contact Block 3A-8 Replaced & Valve Returned to Svc

ML20086S417
Person / Time
Site:	Surry
Issue date:	05/22/1974
From:	Stallings C VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:	Moseley N NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML20086S415	List: ML20086S412 ML20086S417
References
AO-S1-74-04, AO-S1-74-4, NUDOCS 8403010555
Download: ML20086S417 (5)

Text

~ - --

p. .q g\C hi,/ M

c. 4, Sj ' q}dC[ist0 x /x'qcy C

c.<

,m.nl.

-. . t vs.4~ u VIRGINIA ELncTRIC AND PO W M R C o.s11*A N y . ,- p g t:,'t*{

• 111c u n o x13, vin o1 x it uaem , t{,[ /p

'J, c;.! :,i: a -

.. (N liay 22,1974 [ITJg(([N Mr. I cracn C. ::ccoley, Director Scrial he. 129 Iirectort.tc cf I c,ulatory O p rations f0fai/J:0:civ 1.aittu Strten Aten.ic Lncrgy Comiscica Ls , ion 11 - Suite Lib Dochet !!o. 50-230 L a Pcr.thtree Screct, :crthveat License 1:o. IPP.-32

/.tlanta, Ccct;;in 50303

Dear 1.r. l'occlcy:

Turnur.ut to Sarry Pornr Statko Techaical Specification 6.6.3.1, (52 Vi ci: in ;.1'.etric cua Pes:cr Cco nny i.crcby Lubuits forty (40) copien of* /bna :Al Occurrcnce heport 1;o. / 0-SI-74-04.

D c cubstance of thfa rcrort h.a been revicted by thn Station Nuclear S afet r cad 0 rat].:.7, C.c.'ittee and will be piccui en the egenda for the next r:c cting of tho Lv:;teu i,uelear sciety ana Optrating cc::.aittee.

Very truly youro,

). '/ , g g

c. ,

C. II. Stallin';n Vice President-Power Su,cply cnd Production Operaticca P,aclosurea 40 copina of MFSI-74-04 cc: F.'r K. 4 CoHer, Arsiatant Director for O f crat 4ng i'cactora 1.'r . Stanle7 - iWone i

l' f

i f\ -

. 4

/

i

^< L

[ \ \I g[D c, a r C. -

ilg ^o.

! pf383RhPcfdS85%g i

S copy SENT REGION __ 1_

y x.

,_s ,

t ..

/,,.. .

(tl til.6L

['ISEOd13/ej:,..

D u, n ,

, t:::o: f" i -

/x )

. f,*yy %,)u 'k2 en ,< ',.) /

ABNORMAL OCCURRENCE REPORT REPORT NO. A0-SI-74-04 l

FAILURE OF AUXILIARY STEAM CENERATOR FEEDWATER PU:!P DISCHARGE VALVE MOV-FW-151C TO OPEN l

MAY 8, 1974 DOCKET NO. 50-280 LICENSE NO. DPR-32 SURRY POWER STATION VIRGINIA ELECTRIC AND POWER COMPANY

[L Ok y

_ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ . _ _ _ _ _ . _ _ . _ _ .---__-------m------s_ _ - - - - - - -

O .

O I. IfiTRODUCTION In accordance with Technical Specification 6.6.B.1 for Surry Power Station, Operating License Number DPR-32, this report describes an ab-normal occurrence which occurred on May 2, 1974. The Directorate of Regulatory Operations, Region II, was notified on May 2, 1974.

The occurrence reported herein is classified as an abnormal occurrence pursuant to Technical Specification 1.0.I.6 which states that: "An abnormal occurrence is defined as: Engineered safeguard system mal-function or other component or system malfunction which rendered or could render the engineered safeguard system incapable of performing its intended safety function."

The occurrence described herein involved an auxiliary feedwater pump discharge valve which failed to open during a periodic test.

11. SU!DfARY OF OCCURRENCE On May 2, 1974, at approximately 0700 hours0.0081 days <br />0.194 hours <br />0.00116 weeks <br />2.6635e-4 months <br />, with the reactor at 100 per cent power, periodic test PT-15, " Steam Generator Auxiliary Feedwater Pumps," was in progress. Valve MOV-FW-151C had been closed in accordance with the procedure, but failed to open when required in a lator step of the test.

The failure occurred in a Cutler-Hammer motor operated valve controller, size I, magnetic starter service #A50CNVD, Series AI.

III. ANALYSIS OF THE OCCURRENCE The purpose of PT-15-is to demonstrate the= operability of the steam generator auxiliary feed pumps and to exercise the steam generator auxiliary-feedwater pump discharge valves,on a monthly; basis.

r o'$ .

. Os The subject valve is normally open, but was closed as part of the periodic test. When the manually operated control suitch, CS "0V-FW-151C was turned to the "Open" position, the valve motor did not start the valve open because the "Open" contactor was not energized. Contact block 52-C contacts 3A-8 were open, preventing the "open" contactor from energizing.

Contacts 3A-8 are operated by the "Close'* contactor and did not properly make-up when the valve was driven closed. A slight tap on the "Close" contactor-contact assembly caused the 3A-8 contacts to close. The valve was then tested satisfactorily. The 3A-8 contact block was removed and satisfactorily bench tested.

IV. CORRECTIVE ACTION TO PREVENT RECURRENCE The immediate corrective action taken was to replace the 3A-8 contact block and return the affected equipment to service.

The "Close" contactor assembly was also removed from the motor control center and replaced with a spare assembly. The 3A-8 contact block and the contactor assembly have been returned to the manufacturer for evaluation to determine if the possible cause of failure can be established.

9 The licensee will take additional corrective action commensurate with the manufacturer's recommendation, if required.

This failure is not related to other similar failures at the Surry Power Station.

V. ANALYSIS AND EVALUATION OF SAFETY IMPLICATIONS OF THE OCCURRENCE Feedwater is provided to the steam generators after a safety injection to provide a heat-sink 'af ter main feedwater isolation l

O . .

O occurs. The system is designed with two (2) auxiliary feedwater pump discharge valves per steam generator. Since only one (1) discharge valve was cycled at a time during the periodic test, feedwater would have been provided to the steam generator by the redundant path. Also, since the discharge valves are normally left in the "Open" position, a failure of this type is not likely to occur during accident conditions.

IV. CONCLUSIONS i

The licensee concludes that: j

1. The occurrence described herein was caused by a failure of the "Close" contactor assembly.

2. The occurrence reported herein did not affect the safe l operation of the station.

3. ihe occurrence described herein did not adversely affect l

. the health of safety of the general public.

l l

I

_ - _ _ _ _ _ _ _ _ _ . _ _ _ . _ _ - _ _ _ _x