05000271/LER-1980-008-03, /03L-0:on 800203,during Feb 1980 Shutdown,Shock Suppressor RR-2 Found W/No Visible Fluid Level in Sight Glass & Declared Visible Insp Failure.Cause of Leakage Unknown.Snubber Rebuilt & Tested Prior to Reinstallation

/03L-0:on 800203,during Feb 1980 Shutdown,Shock Suppressor RR-2 Found W/No Visible Fluid Level in Sight Glass & Declared Visible Insp Failure.Cause of Leakage Unknown.Snubber Rebuilt & Tested Prior to Reinstallation

ML19294C028
Person / Time
Site:	Vermont Yankee File:NorthStar Vermont Yankee icon.png
Issue date:	03/03/1980
From:	Conway W VERMONT YANKEE NUCLEAR POWER CORP.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19294C025	List: 05000271/LER-1980-008, Forwards LER 80-008/03L-0 05000271/LER-1980-008-03, /03L-0:on 800203,during Feb 1980 Shutdown,Shock Suppressor RR-2 Found W/No Visible Fluid Level in Sight Glass & Declared Visible Insp Failure.Cause of Leakage Unknown.Snubber Rebuilt & Tested Prior to Reinstallation
References
LER-80-008-03L, LER-80-8-3L, NUDOCS 8003060556
Download: ML19294C028 (2)

LER-1980-008, /03L-0:on 800203,during Feb 1980 Shutdown,Shock Suppressor RR-2 Found W/No Visible Fluid Level in Sight Glass & Declared Visible Insp Failure.Cause of Leakage Unknown.Snubber Rebuilt & Tested Prior to Reinstallation

Event date:
Report date:
2711980008R03 - NRC Website

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VTVYS1 0500G271 LER 80-8/3L EVENT DESCRIPTION AND PROBABLE CONSEOUENCES As a result of a visual inspection of Vermont Yankee's safety class shock suppressors during the February 1980 shutdown, RR-2 was found with no visible fluid level in its sight glass.

The snubber was removed and functionally tested in the as-found condition. The snubber did not lock up within the required tolerances and was declared a visual inspection failure. The snubber was repaired and returned to service prior to re-actor startup as required by Tech. Spec. Section 3.6.I.4.

Based on the above, and the lack of any seismic event which would require the snubber to be functional, there were no adverse consequences of this occurrence to the health and safety of the public. There have been no previous failures of this s. ibber reported to the Commission.

CAUSE DESCRIPTION AND CORRECTIVE ACTION Functional testing on the VY test machine was not able to reveal the cause of the leakage. However, upon disassembly no obvious seal degrada-tion was observed though some evidence of snubber fluid Icakage appeared in the rod seal area during the visual inspection.

Snubber RR-2 was com-pletely rebuilt and was functionally tested prior to reinstallation. As a result of the fai' lure of snubber RR-2 to pass the visual examination, the next required inspection interval is 12 months +257..

RR-2 is a 3 1/4" Crinnel Figure 201 Shock Suppressor.