ML20084H517

Telecopy AO BFAO-7439W:on 740609,several Manual Starts Attempted Before HPCI Turbine Started.Caused by Failure of Turbine Stop Valve to Open,Possibly Due to Low Operating Oil Pressure or Improperly Working Oil Relay Valve

ML20084H517
Person / Time
Site:	Browns Ferry
Issue date:	06/19/1974
From:	Eric Thomas TENNESSEE VALLEY AUTHORITY
To:	Oleary J US ATOMIC ENERGY COMMISSION (AEC)
Shared Package
ML20084H520	List: ML20084H517 ML20084H521
References
AO-BFAO-7439W, NUDOCS 8305040418
Download: ML20084H517 (3)

Text

,

a -

0)

(D TENNESSEE \/AL'AJ AUTHOF It'TY PP f7 tI' '

, CHATTANCCGA, TENNESSEE i 37401 I' l, J J

t ~i;;

A

, I ~

X(1i k. -

/f V

ArdMV Q 34.RV C2F PC O ct,fI IN nN.

v 8p PARTN 2 miHIP

-l '

June 19, 1974 f'.? IObi_;[P[} Q\l p .. y[7 5 -l m z i 18 74 > ya) Q Q ~l-

-. ~

Mr. John F. O' Leary, Director D.'-N ,' ."M . )y '

Directorate of Licensing '< **~ Ec:4 g/

Office of Regulation G,g g U.S. Ato:lic Eners Co::: mission ' > -

Washington, DC 20545

Dear l'r. O' Lear /:

TEMIESSEE VALIEi AUDIORITY - 3ROICS FERRY UUCLEAR PLMIT UIIIT 1 -

DOCKDT 170. 50-259 - FACILITY CPE2ATIUG L7CESE DPR AMOR!IAL OCCURREI!CE REPORT 3FAO-743917 The enclosed report is to provide details concerning EPCI turbine which failed to start nenne R r until several atter: pts were made and is subnitted in accordence with Appendix A to Regulator / Guide 1.16, Revision 1, October 1973 This event occurred on Browns Ferry I!uclear Plant unit 1 on June 9, 1974.

. t '.2-~ ~;;== ,

TEIEiESSEE VAIJEi AUTHORITY l'f$f r, r. _. __h</

Ditector of Pouer Production Enclosure CC (Enclosure):

lie. Hornan C. I'oseley, Director Region II Regulator / Operations Office, USAEC 230 Peachtree Street, Hil. , Suite 818 Atlanta, Georgia 30303 y

l y 6 I v f EiG49 o b/ i 8305040418 740619 PDR ADOCK 05000259 S FDR COPY SENT REGION-- M ,'

T ,

a O

U O

• V ABITORMAL OCCURRENCE REPORT  :

Report No.: EFAO-7439h' Report Date: June 19, 1974

, Occurrence Date: June 9, 1974 Facility: Browns Ferry Huclear Plant unit 1 Identification of Occurrence HPCI turbine failed to start manun11y until several attempts were made.

Conditions Prior to Occurrence The unit was at rated. tegerature and pressure imediately following a planned turbine trip.

Description of Occurrence Startup Test Instruction (STI) 27, Turbine Trip, was being conducted. The turbine was tripped at 1:15 p.m., June 9, 1974 The HPCI system was initiated canua/

to be available if recuired to control vessel water level, pressure, and te:nerc.-

ture. Several manual starts were attempted before the HPCI turbine started. The EPCI was declared inoperabic and the required surveillance en other CSSC systens conducted while the reactor uns restarted.

After naintenance and test, the HPCI system was declared operable at 10:00 p. . .

Jane 10, 1974.

Designation cf Arnarent Cause of Occurrence It was observed during each manual start attempt that the turbine stop valve did not fully open and the turbine failed to reach operating speed. Em the stop valve did fully open, the unit operated as designed.

A study of the turbine step and relay valve indicated that, during the start attempts, only the stop pilot valve opened which suggested that the trouble was possibly lov operating oil pressure or the oil relcy valve was not working properly.

Analysis of Occurrence During the brief period of time that the HPCI turbine would not start, all remaining safet/ systems were available, vessel water level was controlled at all times by other systems, and there-vere no adverse conseqaences experienced.

Corrective Action An inspection of the oil relcy valve piston, piston rings, and compression spring revealed a number of sen11 scratches and scores which could cause the relay velve to stick cnd not seat properly. This would cause the stop valve to not fully open.

4 9

s

r- . . < '

n v

G A

Corrective Action (continued') ,

The relay valve piston and seat were disassc= bled and polished; the relay valve body and piping vere cleaned and reassembled. Tne operating oil pressure was checked cnd found to be satisfactory, and the HPCI started satisfactorily on

, six consecutive tests. -

Failure Data The valve is a Schutte and Koerting Company inverted oil operated stop valve.

There is no record of any previcus failures of this nature.

4 6

a e

s O

. s t

a WW e w ee 6- n Tr-+Y" ' ' ' * -'7

• w v - w-- ---es: g- -~ * * - * ' * - e' -rww *-4 -wgw -

tv'N - -M'r w #*+'w-N-- F-*-- Tv v - w vrD-*-+ w r7* w-*"W*'"-+eese--