W3P86-1914, Requests Approval to Use ASME Code Case N-411-1 Re Alternate Damping Values for Response Spectra Analysis to Optimize Number of Seismic Restraints in Various Piping Sys.Code Case Criteria Only Used for Response Spectra Type Analyses
| ML20207B776 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 07/16/1986 |
| From: | Cook K LOUISIANA POWER & LIGHT CO. |
| To: | Knighton G Office of Nuclear Reactor Regulation |
| References | |
| W3P86-1914, NUDOCS 8607180204 | |
| Download: ML20207B776 (1) | |
Text
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LOUISI ANA / 317 BARONNESTREET P. O. BOX 60340
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(504) 595-3100 POWER & L1GHT NEW ORLEANS, LOUISlANA 70160 UTNSNsvsi$
July 16, 1986 W3P86-1914 A4.05 QA Mr. George W. Knighton, Director PWR Project Directorate No. 7 Division of PWR Licensing-B Office of Nuclear Reactor Regulation U.S. Nuclear Regulatory Commission Washington, D.C. 20555
Subject:
Waterford 3 SES Docket No. 50-382 License No. NPF-38 ASME Code Case N-411-1
Dear Mr. Knighton:
Louisiana Power & Light (LP&L) hereby requests approval pursuant to 10CFR50. 55a(a) (3) to use at Waterford 3 the ASME Code Case N-411-1, Alternate Damping Values for Response Spectra Analysis of Class 1, 2 and 3 Piping,Section III, Division 1.
The damping recommendations of the code case will serve as alternatives to the damping values specified in Regulatory Guide 1.61 which is currently used at Waterford 3.
LP&L intends to use the criteria of Code Case N-411-1 to optimize the number of seismic restraints (snubbers) in various piping systems. Code Case N-411-1 criteria will only be used for response spectra type analyses, including OBE,-SSE and hydrodynamic loads. For time-history type loads such as feedwater pump trips, the damping criteria of Regulatory Guide 1.61 will continue to be used.
In the use of Code Case N-411-1, if piping supports are moved, modified, or eliminated, any increased piping displacements due to the greater piping flexibility will be checked to assure that they can be accommodated and that there will be no adverse interaction with adjacent structures, components and equipment.
The appropriate FSAR changes as needed will be implemented in a future update. An expeditious approval is appreciated.
Very truly yours, 7
K.
. Cook Nucl-ar Support & Licensing Manager KWC:GEW:ssf cc:
R.D. Martin, NRC Region IV J.H. Wilson, NRC-NRR 8607180204 860716 NRC Resident Inspectors Office PDR ADOCK 05000382 B.W. Churchill P
PDR 0q W.M. Stevenson 0
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