05000219/LER-1980-058-03, /03L-0:on 801211,snubbers 19/6 & 19/7 on Containment Spray & Core Spray Sys Failed Lockup Test.Caused by Piston Seal Failures.Snubbers Replaced

/03L-0:on 801211,snubbers 19/6 & 19/7 on Containment Spray & Core Spray Sys Failed Lockup Test.Caused by Piston Seal Failures.Snubbers Replaced

ML19340E710
Person / Time
Site:	Oyster Creek
Issue date:	01/09/1981
From:	Fitzgerald M JERSEY CENTRAL POWER & LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19340E708	List: 05000219/LER-1980-058, Forwards LER 80-058/03L-0 05000219/LER-1980-058-03, /03L-0:on 801211,snubbers 19/6 & 19/7 on Containment Spray & Core Spray Sys Failed Lockup Test.Caused by Piston Seal Failures.Snubbers Replaced
References
LER-80-058-03L, LER-80-58-3L, NUDOCS 8101150497
Download: ML19340E710 (3)

LER-1980-058, /03L-0:on 801211,snubbers 19/6 & 19/7 on Containment Spray & Core Spray Sys Failed Lockup Test.Caused by Piston Seal Failures.Snubbers Replaced

Event date:
Report date:
2191980058R03 - NRC Website

text

HRC PCRM 364 U.S. N,tE A3 REIULATCCY COMMI,$SION LICENSEE EVENT REPORT

.h CONTMob ELCCC l l

l l

l l

l (PLEASE PRINT OR TYPE ALL MEQUIRED INFORMATION)

)

leIil IN iJ lO lC lP l1 l@l 0 l 01 - l 0 l010-l0 l0 l-l0 lo l@l 4 l 1 l 1 l 1l 1l@l l

I@

F S 9 WCif434E COct to IS WCEN54NuMOEM 26 28 UCENSE TYP3 44 57 G T $4 CON'T 10111

$ $ lLl@iol5I01010l211 lo @ll 12 l1 l1 l8 10 l@l 0 l i l 0 I 9 f A 11 l@

l 8

40 et coCxgfNgween 66 69 EVENT QATE 74 7S REPoRTOATE EvtNr otsCnirTioN ANo amosasLa CcNsEQUENCEs

_.i o I:1 l During' functional testing snubbers - 9/6 and 19/7 (serial nos. 477171 l

g l and 487s24),' located on the Containment Spray and Core Spray System com-l io 9,i mon suction header, failed the lockup test. Althatgh both snubbers l

l o i s i ; would have been virtually inoperable, they would have perfonned similar l

l C !e i ! to a rigid strut, and there are also 2 vertical pipe hangers within 20 l

I c i :, ; feet of either snubber. Therefore, the safety significance would be l

i minimal in the event of a seismic occurrence.

[

,a,3, 80

?

I 9 SYSTEM

CAUSE

CAUSE COMP _

vALy s l Sl Fl@ l E l@ lB l@ l S l U j P l O l R (T l@ us::::l Dl@ l zl@

ns

.:c:a sus = =

ue:ss:r:::

s sus::::

loisi F

3 to 11 12 12 18 19 20 SEQUENTIAL oC0ymmENCE msP0mt MEVIS3CN O.*(5.',g Ia lo l l_l l ol s; 8l g

10 l3 l lLl

[__j l &l as 30 EVENT YE AR RE*omf No.

Co0E Tvet N

_ 21 22 23 24 2s 27 2:

2s 20 28 22 Aho a NT ug pecuns 3ei popu g.

sy (

wA mgm at N Icl@lol@

Izi@

Izi@

101010101 LY_J@

lY l@

I^ l@

l Bl 2l 0l 9l@

34 2S 24 27 ao 4,

42 43 A4 47 34 CAusa cEsCnipT CN AND CCRRECTIVE ACTIONS h

,,, o, l 'Ihe cause was attributed to piston seal failures. Snubber - 19/6 had g i seal material in the hydraulic fluid and snubber - 19/7 had hydraulic

fluid leakage. Both were replaced with operable spares. The feasi-l bility of replacing scxne or all hydraulic snubbers with mechanical

[

l snubbers is being studied.

i,,,i ovusasTarus @ o"E:fsEv' oiscovany ossCaimoN @

""E spewea NA l

l B l@l Functional Test l

[E_j@ l 0 l 9 l 7 l@l is a

n

=

=

e,g,,,, g,,,,

7 oNr o,,Cm,T, @ l L.C 1,.

LusJLill@o,..<.Lz_J@l l

NA l

NA

.so ~a n o.Su

=acai,rio @

Nu..

w NA l

Fi ITl I o Io Io l@Lzj@l l

..so N.I.'~ubs sac.ierioN@

.won.

NA l

li t a i l o lo lo l@l

?

8 9 19 12 30 Mn ' 9f'"',Vo'

c'" @

l L'_LJ l z l@l NA 30 7

4 9 10 Weekly News Relmeo I

llllllIIl!Illf

,$$yg QESCRIPTI.N 12l ally _iSI 68 49 go. ;

i 3 9 to Mchael J. Fitzgerald (609) 693-6038 3

e.aut on e,EsAmER PHONE:

NN

- s OYSTER CREEK hU1 EAR GDERATING STATICN Forked River, New Jersey 08731 Licensee Event Report Reportable Occurrence No. 50-219/80-58/3L Report Date January 9,1981 Occurrence Date De:enber 11, 1980 Identification of Occurrence Two hydraulic snubbers failed the lockup test during their functional testing.

This event is considered to be a reportable occurrence as defined in the Technical Specifications, paragraph 6.9.2.b.2.

Conditions Prior to Occurrence The plant was operating at steady state power. Major plant parameters at the time of occurrence were:

Power:

Beactor 1877IWt Generator 650 Iwe Flow:

Becirculaticn 15.4 x 104 gpn Feedwater 6.97 x 106 lb/hr Description of Occurrence On Demnhar 11, during the functional testing of hydraulic snubbers installa$ on engineered safety related systens, snnhhars -19/6 and -19/7 (serial numbers 477171 and 487524) located on the suction baMar for the Contairrnent Spray and Core Spray Systems both failed the lockup test. Snubber -19/6 failed due to a frozen piston and snubber -19/7 failed to lock up in the tensicn mode. Both snubbers were disassembled and the main piston seals were found to be worn and broken down.

Acparent Cause of Occtu.mce The cause of the occurrence was attributed to piste., seal failures. In the case of srnihhar -19/6, the seal breakdown was so bad t!.at pieces of the material entered the hydraulic fluid, which made the piston virtually inoperable. In the case of sInihhpr -19/7, the seals were worn enough to permit fluid leakage during piston extension and thus failure of the piston to lock up in that direction.

l l

l

u

-~

Reportable Occurrence Page 2 Report No. 50-219/80-58/3L Analysis of Ouwe Snubbers are installed to limit piping movernent during seismic events an:1 during transient canditions. The snubbers installed on the suction header are all positioned horizontally. They are arranged in pairs, with each snubber of a pair approximately 5 - 10 feet apart and on opposite sides of the suction hearler. Snnhhors -19/6 and -19/7 constitute a pair, and although both would have been virhially inoperable, they muld have perfonned in a manner similar to a rigid strut. Also, there is a vertical pipe hanger located within 7 feet of one snubber and another vertical pipe hanger located within 20 feet of the other snubber. Therefore, in the event of a seismic occurrence, the safety significance would be considered minimal.

Corrective Action

Both snubbers were replaced with operable spares. The functional testing of additional snubbers will be performed in accordance with the Technical Specifica-tions, paragraph 4.5.0.4.

At the present time there is an engineering study examining the feasibility of replacing sme or all hydraulic snubbers with mechanical snubbers.

Failure Data Manufacturer - Bergen-Patterson Pipesupport Corp.

Model - HSSA-10 (max.10,000 Ibs. force)

/