ML19242D156

Commits to Maintain 48-inch Containment Purge Valves in Closed Position in Modes 1-4 Until Demonstration That Valves Will Meet Functional Requirements During Accident Conditions

ML19242D156
Person / Time
Site:	Farley
Issue date:	08/07/1979
From:	Clayton F ALABAMA POWER CO.
To:	Schwencer A Office of Nuclear Reactor Regulation
References
NUDOCS 7908140569
Download: ML19242D156 (1)

Text

Alabama Power Company 600 North 18th Street Post Office Box 2641 Birmingham Alabama 35N1 Telephone 205 323-5341 bbo sc ,";i AlabamaPower A

the soumem eWinc system August 7, 1979 Director, Nuclear Reactor Regulation U. S. Nuclear Regulatory Coenission Washington, D.C. 20555 Attn: Mr. A. Schwencer J. M. Farley Nuclear Plant Docket No. 50-348 Containment Putze Valves

Dear Mr. Schwencer:

In a meeting held on July 31, 1979 between the Nuclear Regulatory Commission and Alabama Power Company, the NRC requested commitments from Alabama Power Company concerning operation of both the 48-inch and 18-inch purge valves used at the Farley Nuclear Plant.

Alabama Power Company commits to maintain the 48-inch containment purge valves in the closed position in modes 1, 2, 3, and 4 until it can be demonstrated that the valves will meet functional requirements during accident conditions. The valve supplier, Henry Pratt Co., indicated that there would be no question that the 48-inch valves would function properly under accident conditions f rom a 65 percent open position. Alabama Power Company is pursuing verification of methods to block the maximum open position of the 48-inch valves. Further information will be provided upon completion of this verification.

The valve supplier has conducted further anal f sis on the 18-inch con-tainment purge valves that demonstrate that the valves meet operability requirements under all accident conditions. Maximum torque developed under worst case conditions is 12,000 in.-lb. which is less than the 15,000 in.-lb.

used as design criteria for the valves. These torque values result in stresses much less than the yield point for materials usta.

AJabama Power Company's position, therefc 0 cemains that continuous purging during operation with the 18-inch (mini-purge) valves is safe under all accident conditions.

Very :ruly yours, F. L. Claytgn, Jr.?

FLCJr/TNE:bhj l L 'k cc: Mr. R A. Thomas t " ' '-

Mr. G. F. Trowbridge dIdE df

?Y I O 7908I40 667 /#