05000336/LER-1979-028-03, /03X-1:on 790904,during Routine Power Operation, Hydraulic Snubber on Main Stream Atmospheric Dump Valve B Declared Inoperable.Caused by Personnel Breaking Fluid Reservoir & Fatigue Failure of Reservoir Outlet Nipple

/03X-1:on 790904,during Routine Power Operation, Hydraulic Snubber on Main Stream Atmospheric Dump Valve B Declared Inoperable.Caused by Personnel Breaking Fluid Reservoir & Fatigue Failure of Reservoir Outlet Nipple

ML19254F289
Person / Time
Site:	Millstone
Issue date:	11/02/1979
From:	Crockett J NORTHEAST UTILITIES
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19254F231	List: 05000336/LER-1979-028, Forwards LER 79-028/03X-1 05000336/LER-1979-028-03, /03X-1:on 790904,during Routine Power Operation, Hydraulic Snubber on Main Stream Atmospheric Dump Valve B Declared Inoperable.Caused by Personnel Breaking Fluid Reservoir & Fatigue Failure of Reservoir Outlet Nipple
References
LER-79-028-03X, LER-79-28-3X, NUDOCS 7911070539
Download: ML19254F289 (1)

LER-1979-028, /03X-1:on 790904,during Routine Power Operation, Hydraulic Snubber on Main Stream Atmospheric Dump Valve B Declared Inoperable.Caused by Personnel Breaking Fluid Reservoir & Fatigue Failure of Reservoir Outlet Nipple

Event date:
Report date:
3361979028R03 - NRC Website

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80 EVENT DESCillPTioN AND PROBADLE CONSEQUENCES h lo 121 l During routine power operation, a hydraulic snubber located on the B main steam almas-l lo l3 l 1 pheric dump valve was declared inoperable due to a broken off fluid reservoir.

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l snubber was replaced. Facility operation was in accordance with Technical Specificaticn j O 4 3.7.8.1. A second identical failure, shearing of the reservoir outlet, occurred on l

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l 10/3/79, and a replacement unit again installed.

Snubber data:

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1 Grinnell, Fia. 201, 2-1/2 inch bore x 5 inch stroke.

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40 41 42 43 44 47 CAUSE DESCRIPTION AND CORRECTIVE ACTION 3 h 1110110riginal failure attributed to personnel breakina off reservoir.

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