ML19347F850

Interim Rept Re Westinghouse Valves Failure to Close Completely Under Preoperational Test Conditions,Initially Reported on 810217.Westinghouse Has Modified 4-inch Valves for Use as Prototypes.Final Rept to Be Submitted by 811016

ML19347F850
Person / Time
Site:	Comanche Peak
Issue date:	05/21/1981
From:	Gary R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC)
To:	Madsen G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
References
10CFR-050.55E, 10CFR-50.55E, TXX-3322, NUDOCS 8105260465
Download: ML19347F850 (2)

Text

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n k TEXAS UTILITIES GENERATING COMPANY 2003 BRYAN 'IVWER = DALLAS.TEXA8 76201

'"bf,'!!!:' May 21, 1981 TXX-3322 Mr. G. L. Madsen, Chief Reactor Projects Branch U. S. Nuclear Regulatory Commission Office of Inspection & Enforcen. ant 611 Ryan Plaza Dr., Suite 1000 Docket Nos. 50-445 Arlington, Texas 76012 50-446 COMANCHE PEAK STEAM ELECTRIC STATION WESTINGHOUSE GATE VALVES FILE: 10110

Dear Mr. Madsen:

In accordance with 10 CFR 50.55(e) we are submitting the attached interim report concerning Westinghouse valves that failed to close completely under pre-operational test conditions. This matter was verbally reported to your Mr. R. G. Taylor on February 17, 1981, and we have submitted an interim report to you forwarded by TXX-3288 dated March 13, 1981.

Per our letter TXX-3288, we have re orted the description and cause of the deficiency, engineering evaluation of the safety implications, and the corrective actions planned for the Westinghouse three (3) inch valves. The attached report contains planned corrective actions for the Westinghouse four (4) inch valves.

We will submit a final report when all required modifications have been finalized and dates for implementation can be established. A target date of October 16, 1981 is anticipated.

If we can provide any additional information, please advise.

Very truly yours, An

.W,.L RM1. Gary //

m RJG:kh Attachment cc: NRC Region IV - (0 + 1 copy)

Director, Inspection & Enforcement - (15 copies) c/o Distribution Services Branch, DDC, ADM.

U. S. Nuclear Regulatory Commission Washington, D. C. 20555 8105260'M6..

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,'i i TXX-3322 May 21, 1981 Attachment WESTINGHOUSE GATE VALVES Corrective Actions Westinghouse has modified the four (4) inch valves to be used as prototypes. The modifications consist of the following:

Model 4CM88

1. Change to Limitorque SB-0-25 motor operator.

2. Rewire the operator for limit closing control.

3. Change to new yoke that will accept an SB-0-25.

4. Change valve internals to accept higher stall loads,

a. Stem (same size 1.25")

b. Stem Disc Connection

c. Re-machine valve disc to accept new stem-disc connection parts.

Model 4GM87

1. Change operator gear ratio to guarantee adequate thrust capability at 80 percent voltage.

2. Re-wire operator for limit closing control.

Prototypes of each design modification will undergo verification flow testing which is expected to be completed by the end of June. Based on successful completion of these tests, parts should be available by September to make the necessary modifications.

For those three (3) and four (4) inch valves already installed, Westinghouse will provide a field modification kit and a field service engineer to supervise the modifications. Those valves that have not been it.ctalled will be returned to Westinghouse for modifications.

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