ML20127L746
| ML20127L746 | |
| Person / Time | |
|---|---|
| Site: | Washington Public Power Supply System |
| Issue date: | 05/16/1985 |
| From: | Sorensen G WASHINGTON PUBLIC POWER SUPPLY SYSTEM |
| To: | Adensam E Office of Nuclear Reactor Regulation |
| References | |
| GO1-85-0116, GO1-85-116, NUDOCS 8505230072 | |
| Download: ML20127L746 (2) | |
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Washington Public Power Supply System N
- 9 2 // W P.O. Box 968 3000 GeorgeWashingtonWay Richland, Washington 99352 (509)372-5000
-May 16, 1985 G01-85-Oll6 J
-Director of Nuclear Reactor Regulation Attention: Elinor G. Adensam, Chief Licensing Branch No. 4 Division of. Licensing U. S. Nuclear Regulatory Commission Washington.0.C. 20555
Subject:
NUCLEAR PROJECT N0. 1 DOCKET N0. 50-460 REQUEST FOR CODE CASE N-411 APPROVAL
Reference:
Letter: G. W. Knighton to R. J. Harrison:
Seismic Piping Analysis - Seabrook Station Docket Nos:
50-443 and 50-444 In accordance with Article NCA 1140 of the ASME Section III Code, the Supply System requests. approval to apply Code Case N-411 as described below.
~
On September 17, 1984, the Main Committee of the ASME approved Code Case N-411.
This Code Case provides alternate damping values for the seismic analyses of Class 1, 2 and 3 piping systems which may be used ir. lieu of the values. given in Table N-1230-1 of Section III of the ASME Boiler and Pressure Vessel ' Code.
The N-1230-1 values, incidentally, are the same as
- those given in Regulatory Guide 1.61.
It is requested that the use of Code Case N-411 be approved by your office for the design of the WNP-1 plant.
The N-411 damping values, which were originally recommended by the Pressure Vessel Research Committee (PVRC), would be applied in the following circumstances:
1.
In the piping design conformance analyses where their use would preclude the - requirements for harhare nodifica-ti ons.
2.
Where appropriate,.in the optimization of pipe supports (redesign and new design) for seismic requirements.
- Based on the use of the N-411 damping values, the piping design conformance analyses for the WNP-1 project will continue to include, but will not be limited to, verification that:
e All support locations are necessary, o Excessive pipe deflections are not introduced when supports are optimized, 8505230072 850516 PDR ADOCK 05000460 t/
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a G01-85-Oll6 DIRECTOR OF NUCLEAR REACTOR REGULATION
' Page 2 e Postulated pipe break locations have been properly consid-
- ered, o Equipment nozzle. loads have also been properly considered.
-Each analysis utilizing the damping values of Code Case N-411 will ~be so specified on the N-5 Data Report.
The mechanism for'. implementing the above will be incorporated into our project; procedures, and the use of the code case damping values will be documented in a future amendment to the-FSAR and, the piping design specification.
Please note that permission to apply Code Case N-411 damping. values has already been granted to another nuclear project (see reference). -As the piping conformance analyses have 'already been initiated, the Supply System would appreciate receiving your approval for WNP-1 to apply Code Case N-411 by June 28, 1985.
G. C. Sorensen, Manager Regulatory Programs (340)
GCS:LC0:llw cc:
N.D. Amaria, UE&C (898)
T. Kenyon.NRC (116)
N. Reynolds, BLCPR E. Revell, BPA (399)
FDCC (899) e i m.