ML18114A694

Failure of Solenoid Operated Valves to Meet IE Bulletin 79-01 Environ Qualification Requirements.Environmentally Unqualified Valves Have Been or Will Be Replaced

ML18114A694
Person / Time
Site:	Surry, North Anna
Issue date:	06/14/1979
From:	VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
Shared Package
ML18114A693	List: ML18114A692 ML18114A694
References
NUDOCS 7906180538
Download: ML18114A694 (2)

Text

Attachment page 1 of 2 FAILURE OF SOLENOID _OPERATED VALVES TO MEET I.E. BULLETIN 79-01 ENVIRONMENTAL QUALIFICATION REQUIREMENTS I. Introduction During a review of Class lE equipment pursuant to IE Bulletin. 79-01, the Architect-Engineer identified a solenoid valve, ASCO model No.

8320Al02, as potentially environmentally unqualified. This valve was used in the following applications in the Surry 1 and 2 and North Anna 1 containments:

Surry Unit 1: SOV-BD-lOOA, Band C (3 valves)

Surry Unit 2: SOV-BD-200A, Band C (3 valves)

North Anna 1: SOV-SS-lOOA, 101A, 102A, 104A SOV-SS-106A, 112A (Six valves)

In all locations, the solenoid valves will be replaced with environ-mentally qualified valves.

II. Surry 1 and 2 Valves The six valves identified at Surry (3 in each unit) control the admission and venting of operating air for the containment trip valves on steam generator blowdowri 1ines.

III. North Anna 1 and 2 Valves The six valves identified at North Anna 1 control the admission and venting of operating air for the containment isolation trip valves for the sampling system in the following applications:

SOV-SS-lOOA Pressurizer Liquid Sample SOV-SS-lOlA Pressurizer Vapor Sample SOV-SS-102A RCS Cold Leg Sample SOV-SS-104A Pressurizer Relief Tank Sample S0V-SS-l06A RCS Hot Leg Sample SOV-SS-112A. Steam Generator Surface Sample These valves are normally de-engergized, and only opened to obtain a sample.

North Anna Unit 2 also uses 6 valves in similar applications.

7906180 53'2

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• Attachment page 2 of 2 IV. Probable Consequences and Status of Redundant Systems The failure mechanism is a plastic plug which could melt and block an air port in the solenoid actuator preventing proper operation. In all applications listed above, a fully redundant outside containment isolation trip valve would have provided containment isolation in the event one or more of these valves failed. Therefore, the health and safety of the general pu~lic was not affected.

V. Corrective Action In all cases, the environmentally unqualified valves have been or will be replaced with qualified valves. The status of this effort is as follows:

Unit Status Surry l Change-out completed Surry 2 prior to startup North Anna 1 First outage following receipt of replacements North Anna 2 Change-out completed