ML20072G710
| ML20072G710 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 06/02/1983 |
| From: | Manno S NIAGARA MOHAWK POWER CORP. |
| To: | Starostecki R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, 6770, NUDOCS 8306280605 | |
| Download: ML20072G710 (2) | |
Text
-.o M Y NIAGARA RUMOHAWK
' NIAGARA MOHAWK POWER CORPORATION /300 ERIE BOULEVARD WEST, SYRACUSE N.Y.13202/ TELEPHONE (315) 474-1511 I
SAMUEL F. MANNO VICE PRESIDENT NUCLE AR CONSTRUCTION June 2, 1983 (6770)
Mr. R. W. Starostecki, Director U.S. Nuclear Regulatory Commission Region I Division of Project and Resident Programs 631 Park Avenue King of Prussia, PA 19406 Re: Nine Mile Point Unit 2 Docket No. 50-410
Dear Mr. Starostecki:
Enclosed is a final report-in accordance with 10CFR50.55(e) for the deficiency concerning valves manufactured by Clow Corporation. This condition was reported via telephone to Mr. Wiggins of your staff on September 23, 1982, as a potentially reportable deficiency. An interim 30-day report was submitted via our letter dated October 22, 1982.
Very truly yours,
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. Ma n Vice President Nuclear Construction SFM/TL:ja Enclosure xc: Director of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, DC 20555 Mr. R. D. Schulz, Resident Inspector 8306280605 830602 gDRADDCK 05000410 PDR h
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NIAGARA M0 HAWK POWER CORPORATION NINE MILE POINT - UNIT 2 4
DOCKET N0. 50-410 Final Report for a Problem-l Concerning Clow Valves 4
Description of the Deficiency Clow Corporation had advised Stone & Webster Engineering Corporation that 16 valves that were shipped to the Nine Mile Point Unit 2 site were not heat treated as required by ASME Code.
In accordance with ASME Code, heat treatment is required for carbon steel pipe or formed portions of pumps or valves with a wall thickness greater than 3/4 inch which have been cold bent
- or formed.
l The valve bodies for the valves in question were manufactured from SA515 Grade 70 carbon steel plate. The thickness of the plate was greater than 3/4 inch.
The plate was rolled into hollow cylindrical form by cold working.. These valves are used in the following safety-related systems:
(1) service water system, (2) low pressure core spray system and (3) residual heat removal system.
Analysis of Safety Implications
- For the valves in question, an analysis was performed by Stone & Webster Engineering Corporation to evaluate the tolerance of the valve bodies to the residual stresses in terms of minimum required fracture toughness. Based on the.results of the analysis, if this problem were to have remained uncorrected, the safe operation of the plant would not have been adversely affected.
Mcwever, the following actions will be taken:
1 The 16 valves were shipped back to the Clow Corporation for heat treatment rework. The rework is expected to be i
completed by August 31, 1983.
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