ML19351D466
| ML19351D466 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 10/03/1980 |
| From: | Rich Smith VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | Ippolito T Office of Nuclear Reactor Regulation |
| References | |
| WVY-80-139, NUDOCS 8010100218 | |
| Download: ML19351D466 (2) | |
Text
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VERMONT Y AN KEE N UCLEAR POWER cot &OR ATION SEVENTY SEVIN GROVE STREET B.3.2.1 RUTLAND. VERMONT 05701 WVY 80-139 H EPLY TO:
ENGINEERING OFFICE TURNPIKE RO AD WESTDORO M ASS ACHUSETTS 01581 TELEPHONE 617-366-9011 3
United States Nuclear Regulatory Commission Nashington, DC 20555 Attention:
T. A. Ippolito, Chief Operating Reactors Branch #3 Division of Operating Reactors
References:
(a) License No. DPR-28 (Docket No. 50-271)
(b) USNRC Letter to VYNPC dated November 9,1979 (c) VYNPC Letter (WVY 79-148) to USNRC dated December 27, 1979 (d) VYNPC Letter (WVY 80-15) to USNRC dated January 21, 1980 (e) VYNPC Letter (WVY 79-6) to USNRC dated January 9,1979
Subject:
Purge and Vent Valve Operability - Supplemental Information
Dear Sir:
Reference (b) provides the NRC's interim position regarding the use of containment purge and vent valves. The interim position requires the licensee to establish the need to purge or vent, confirm that the subject valves will remain operable under the most severe design basis accident flow conditions and can close within the ',ime limits stated in Technical Specifications.
Information justifying the use of one vent valve (SB-6) was previously transmitted to the NRC in References (c) and (d).
The purpose of this letter is to inform you that we now have information and test results supplied by the valve manufacturer which indicate that the remaining purge and vent valves (SB-16-19-7 A, 7B, 8, 9,10, 23 and SB-7) are capable of operating under the most severe design basis accident flow conditions. Specifically, calculations done for these valves confirm that:
they will close from any disc position in the time required by Technical Specifications, and, the resulting dynamic loadings from the postulated ascending pressures associated with a LOCA will not damage critical valve parts.
Taking into account that the torque coefficients used for these calculations have been verified by tests,and the conservatisms in the 8 01010 0.2/2P *.
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United States Nuclear Regulatory Commission October 3,1980 Attention:
T. A. Ippolito, Chie; Page 2
+-g calculations, we feel that the use of purge and vent valves as described in Reference (e) and allowed by Technical Speciications is justified.
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We trust this information is satisfactory; however, should you have any
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questions do not hesitate to call.
Very truly yours, l
VERMONT YANKEE NUCLEAR POWER CORPORATION R. L. Smith Licensing Engineer RLS/ncj l
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