ML20147B334

LER#78-003/03L-1 on 780710:Maintenance on Safety Sys Hydraulic Snubber Previously Found to Have Low Fluid Accumulator Level Revealed 2 Deteriorated o-rings Made W Polyurethene Seals Instead of ethylene-propylene Seals

ML20147B334
Person / Time
Site:	Rancho Seco
Issue date:	07/10/1978
From:	Colombo R SACRAMENTO MUNICIPAL UTILITY DISTRICT
To:
Shared Package
ML20147B330	List: ML20147B325 ML20147B334
References
LER-78-003-03L, LER-78-3-3L, NUDOCS 7810100077
Download: ML20147B334 (1)

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F.E POR T D A T E 60 EVENT DESCRIPTION AND FROB ABLE CONSEQUENCES h lo1211 The original report (RO-78-03) described the discoverv of a low fluid I a 3 I accumulator on a safety systen hydraulic snubber. Since that time, g 10141I maintenance work on the snubber revealed two deteriorated "0-rings" in l i

10151 L_the snubber valve body. Subsequent analysis found the seals were 1 Lo_Ls J l nolvurethene rather than the proper material, ethylene propylene. I i

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LN,j@ y@ l B l 2l0 l 9l@ 3 el 42 dj 44 47 CAUSE DESCRIPTION AND CORREC GVE ACTIONS h g l All Bercen-Patterson snubbers were cricin,11v delivorod virh nnivornthnnnI 1i 11 1I seals. Many units were returned for ren1ncement with crhvinnn- I tilstI propylene seals after determinat-lon thne nnivurcebonc conic torn I i a l unaccentable in certain environments. Apparentiv, these seals were f g I missed in the rebuild. l ,

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