ML20085G640
| ML20085G640 | |
| Person / Time | |
|---|---|
| Site: | Browns Ferry  |
| Issue date: | 12/23/1974 |
| From: | Eric Thomas TENNESSEE VALLEY AUTHORITY |
| To: | Case E US ATOMIC ENERGY COMMISSION (AEC) |
| References | |
| NUDOCS 8308290241 | |
| Download: ML20085G640 (2) | |
Text
hRIML OCCURREICE RIFORT
.s Report No.: BFAO-50-259/7459U Report Date: December 23, 1974 Occurrence Date: Decenber 13, 1974 Facility:
Browns Ferry Nuelcar Plant unit 1 Identification of Occurrence Failure of seconda:'/ containment isolation damper solenoid valves.
Conditions Prior to Occurrence The reactor was at full power and surveillance testing of the secondary containment isolation system was in progress.
Description of Occurrence While conducting a curveillance test, solenoid valve FSV-64-lh for reactor zone air supply inboard isolation dc per and solenoid valve FSV-64 41 for reactor 4
zone exhaust to standby gas system crosstie de=per failed to operate. Both solenoid valves operated after being lightly tapped.
i>
Decirnation of Antarent Cause of Occurrence The solenoid valves failed to operate when deenergized due to the pilot valves L
sticking in the cents.
Analvcis of Occurrence The reactor zone air supply inboard isolation derper has en outboard icolation darper in series which would have isolated the reactor zone if recuired.
Tne p
reactor zone exhaust to standby gas system crocctie dc=per has a damper in f
parallel which would have permitted exhausting from the reactor zone throur;h. the
~
stendby gas treattent system. The failure did not prevent cafe operation of the plant. The failure cauced no dc=cge to cny systers, structures, or components.
h There uere no adverse effects to the health end safety of the public, end there vere no personnel in, juries or exposures due to this occurrence, f
Corrective Action The colcnoid valves were replaced with new colenoid valves, and proper opemtion j
of the colenoid valves and dc=pers was verified. -The operating' instructions are
-[
being revised to require operation of these valves when fan operation is switched j
from fan A to fan B.
This providen more frequent cperation of the valves and will j
decrease the probability of valve stickage.
-l The instruction revicions will be cocpleted and i=plementation started by February 1, 1975.
~
Failure Data
-Ho previous failures caused by the pilot valve sticking to the ceat has occurred.
The colenoid valve is ASCO catalog Ho. HB830281RV.
8308290241 741'223 PDR ADOCK 05000259 S
PDR a
1 r- ' x
/
h
/.._x I
s c
\\
\\ ;
\\
l
~
TENN ESECE VALLEY AUTHORITY cre An,esaccr. Tr,Nc : -cc m.r :
December 23, 1974
/
i
,,r. sa, c on u,,. Cnce t.
Acting Director of Licensing Office of Eerulation x
u U.S. 1.tcric Energ Ccamission Unshin;; ton, DC 205L5
Dear I:
- r. Cese:
i T2"'ECJ 2: VALLE'l flTHORIfl - BEC.._:S FERRY !!UCLE!.R FLI.IIT U:iIT 1 -
Dn,.,a,,. 0.. 0 c p 9
,c
,. t L,u,, C,c-,'.,.,.
,7..,
.us Ds p_,-3 3 - a 0m,,,,,.L LIL, a. c..,
vv.
7 v.
u.~.a
.n
.~ wrv:.. zu !.0
',O
^:y~ ^j,/74 7,.e' y, v,.,
gu,,v,ga.n.,,,
Tr.c cnclosed report is to provide details concerning it.ilure of cecond2rf conttiment isolation dager solenoid vu.lves end is submitted in c c:r3cce uiti.'.p?cndic n to Ecculatorf Guide 1.16, Revicicn 1, n-t:bcr II/3 Teic event occurred on 3rwis l'errf liuclear Flan.
ait.L ca Jee'c:.ber 13, 1974 Veri traly yorc, TE:~I!LCSI: Vll25i AUTEORITI
/
' OlW e
E. F. Ibancs Director of Fo.:er Production Enclocure CC (Ihclocure):
l'r. Lorzen C. .oceley, Director Regica II Ee ult.torf O? crc.tions Office, USAEC 230 Fecchtrce Street, :,~.i., Suite eld
/ttlanta, Georcia 30303 I
l
- 4 O D V
.i.o v J t
/
I MPV SFWP REGION
_n r