ML19317F283

RO 287/77-01:on 770126,reactor Bldg Isolation Valve 3RC-7 Found Inoperable.Probable Causes:Valve Not Cycled After 770102 Adjustment & Paint on Valve Stem.Stem Cleaned & Oiled & Packing Loosened.Deficiency in Personnel Actions Noted

ML19317F283
Person / Time
Site:	Oconee
Issue date:	02/15/1977
From:	DUKE POWER CO.
To:
Shared Package
ML19317F278	List: ML19317F277 ML19317F283
References
RO-287-77-01, RO-287-77-1, NUDOCS 8001090616
Download: ML19317F283 (1)

Text

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o DUKE POW 2R COMPANY ,

OCONEE UNIT 3 -

j Report No.: R0-287/77-1 Report Date: February 15, 1977 Occurrence Date: January 26, 1977 Facility: Oconee Unit 3, Seneca, South Carolina Identification of Occurrence: Reactor Building containment isolation valve 3RC-7 inoperable Conditions Prior to Occurrence: Unit at 100 percent full power Description of Occurrence:

On January 26, 1977, while performing a channel 5 and 6 Engineered Safeguards (ES) on-line test, Reactor Building containment isolation valve 3RC-7 failed to close. This valve is located in the pressurizer sample line and is required i

to close upon receiving an ES actuation signal in order to assure containment

integrity. Valve 3RC-7 was isolated within one and one-half hours by locking closed the redundant isolation valves 3RC-5 and 3RC-6, pursuant to Oconee Technical Specification 3.6.4.b.2.

Apparent Cause of Occurrence:

Investigation revealed that two circumstances could have resulted in the malfunction of valve 3RC-7. The failure could have been related to mainte-nance performed on the valve on January 2, 1977. The maintenance was minor and consisted of adjusting the valve packing; however, the valve was not cycled af ter the adjustment as required by the maintenance procedure. Also, paint was discovered on the valve stem which could have prevented the valve from functioning properly.

Analysis of Occurrence:

Valve 3RC-7 was properly isolated in compliance with Oconee Technical Speci-ficatica 3.6.4(b)(2) by securing the redundant valves, 3RC-5 and 3RC-6, in the closed position. In the event that containment integrity had been required, the redundant isolation valves were available to close upon an ES actuation.

It is concluded that the health and safety of the public were not affected.

Corrective At: tion:

The valve stem was cleaned and lubricated and the valve packing was loosened.

The valve was cycled several times and functioned properly. This occurrence was discussed with the personnel involved and the deficiency in their actions identified. Also, all maintenance personnel will review this incident to assure that maintenance procedures are followed properly.

8001090bl

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