ML19305D194

Final Deficiency Rept Re Stress Analysis of Certain Lines in Low & High Head Safety Injection Sys.Affected Pipe Supports Are Being re-examined Under New Loads.Mods to Existing Design of Three Supports Determined Unneccessary

ML19305D194
Person / Time
Site:	North Anna
Issue date:	04/08/1980
From:	Sylvia B VIRGINIA POWER (VIRGINIA ELECTRIC & POWER CO.)
To:
References
314, NUDOCS 8004140167
Download: ML19305D194 (1)

Text

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VinorNrA EIiECTRIC AND Powan COM.PANY Rrcuxown,Vznomma 20201 April 8, 1980

• Mr. James P. O'Reilly - Serial No. 314 Office of Inspection and Enforcement PO/RMT:baw U. S. Nuclear Regulatory Commission Docket No: 50-339-Region II -

-- 101 Marietta Street, Suite 3100 ,,. . .

Atlanta, Georgia 30303

Dear Mr. O'Reilly:

Pursuant to the provisions of 10CFR50.55(e), the NRC Region II was notified on March 11, 1980 of a deficiency in the stress analysis of certain lines in the low and high head safety injection systems. The subject lines, which have not been stress analyzed for fluid temperatures below 70*F, transport water from the RWST to the Reactor Coolant System cold legs during the injection phase of the Emergency Core Cooling System, and as such can be exposed to temperatures in the 40-50*F range. 'Ihe resulting pipe wall temperatures below 70*F could create limits on equipment and pipe supports which have not been previously analyzed.

r All affected pipe supports on Unit 2 are being reexamined under the new loads. So far modifications to the existing design of three supports (SI-A-80, SI-R-86 and 2-RH-R-20) have been determined necessary. The new designs for these pipe supports have been completed and will be implemented prior to power opeIation above 5%. Any further pipe support changes required as a result of the on-going safety injection temperature excursion review, will be handled accordingly.

This report constitutes our final report on this matter. Should you require l

additional information, please contact this office.

I Very truly yours, B. R. Sylvia Manager-Nuclear Operations cc: Mr. Victor Stello, Director Office of Inspection and Enforcement Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation 8004140l67. . . . .