ML19262C240

LER 80-002/01T-0:on 800117,during Operational Mode 5,w/RCS Temp at 100 F & Atmospheric Pressure & RCS Level mid-loop W/ RHR Flow at 1,700 Gpm,Reactor Vessel Vent Educator Was in Svc,Causing Negative Pressure

ML19262C240
Person / Time
Site:	Beaver Valley
Issue date:	01/30/1980
From:	Werling J DUQUESNE LIGHT CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19262C238	List: ML19262C237 ML19262C240
References
LER-80-002-01T, LER-80-2-1T, NUDOCS 8002080448
Download: ML19262C240 (2)

Text

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EVENT DESCRIPTION AND PRC8 A8LE CONSEQUENCES h 100F and atmospheric  ;

[TTTI IThe plant was in operationat Mode 5 with RCS temperature at The RCS level was mid-loop with RHR flow at 1700 gpm. The reactor vesselg O 3 l pressure.

C 4 l vent eductor was in service in preparation for refueling. A low flow alarm was l 0 s Ireceived and low flow and low motor current were indicated. A second pump was l started and was also air-bound. The pumos were vented, core flow was rapidly i Lc_ls J O i l restored and there were no implications to the health and safety of the general l l

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Attachment To LER 80-02/01T Beaver Valley Power Station Duquesne Light Company Docket No. 50-334 Cause Description And Corrective Actions (continued) drained into the loops. This entrained air later air-bound the pumps.

The procedure will be revised to constantly vent the RHR pumps when putting the vessel vent eductor into service. This had been a recurring problem when loops were drained to mid-span while RHR flow was 3000-4000 gpm. Flow is now normally between 1000 and 2000 gpm and has not lately been a problem.

A method is being researched to possibly constantly vent the RHR pumps automatically.

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