ML20197E205
| ML20197E205 | |
| Person / Time | |
|---|---|
| Site: | Vermont Yankee File:NorthStar Vermont Yankee icon.png |
| Issue date: | 05/13/1986 |
| From: | Capstick R VERMONT YANKEE NUCLEAR POWER CORP. |
| To: | Rooney V Office of Nuclear Reactor Regulation |
| References | |
| RTR-REGGD-01.060, RTR-REGGD-01.092, RTR-REGGD-1.060, RTR-REGGD-1.092 FVY-86-41, NUDOCS 8605150193 | |
| Download: ML20197E205 (1) | |
Text
VERMONT YANKEE NUCLEAR POWER CORPORATION RD 5 Box 169. Ferry Road, Brattleboro, VT 05301
,,,Ly 70 y
ENGINEERING OFFICE 1671 WORCESTER ROAD FRAMINGHAM, MASSACHUSETTS 01701 TELEPHONE 617 872-8100 May 13, 1986 FVY 86-41 United States Nuclear Regulatory Commission Washington, DC 20555 Attention:
Office of Nuclear Reactor Regulation Mr. V. L. Rooney, Sr. Project Manager BWR Project Directorate No. 2 Division of BWR Licensing
References:
(a) License No. DPR-28 (Docket No. 50-271)
(b) Letter, VYNPC to USNRC, FVY86-26, dated March 27, 1986 (c) Letter, VYNPC to USNRC, FVY86-33, dated April 11, 1986
Subject:
Request for Approval of PVRC Damping Analysis Method - Response to Additional Request for Information
Dear Sir:
The purpose of this letter is to respond to the NRC Staff's May 8, 1986 request for additional information concerning the subject request for approval of PVRC damping analysis methods, submitted March 27, 1986 (Reference (b)).
Specifically, confirmation was requested that Vermont Yankee's analysis is a three-dimensional analysis and that the analysis is not terminated at an arbitrary frequency threshold, but rather when peak amplitude has sufficiently diminished.
Please be advised that analysis of piping is three dimensional, utilizing NRC Regulatory Guide 1.92 Guidelines for combination of modal responses and spatial components. The cut-off frequency used is 33 Hz minimum, consistent with response spectra generated based upon Regulatory Guide 1.60 Criteria.
"PVRC-damped" spectra are not used to analyze systems containing heavy equipment where such equipment could modify seismic load definition of piping.
We believe this information adequately addresses the Staff's additional requests; however, should you have further questions or require additional information regarding this matter, please contact this office.
Very truly yours, VERMONT YANKEE NUCLEAR POWER CORPORATION-Cpt P
Licensing Engineer RWC/mmt i}O