ML13330B251
| ML13330B251 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 09/18/1987 |
| From: | Medford M Southern California Edison Co |
| To: | NRC Office of Administration & Resources Management (ARM) |
| Shared Package | |
| ML13330B252 | List: |
| References | |
| NUDOCS 8709280106 | |
| Download: ML13330B251 (1) | |
Text
Southern California Edison Compan y 1P 25 A 9 39 P. 0. BOX 800 2244 WALNUT GROVE AVENUE ROSEMEAD, CALIFORNIA 91770 M.O.MEDFORD TELEPHONE MANAGER OF NUCLEAR ENGINEERING (818) 302-1749 AND LICENSING September 18, 1987 U. S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, D.C. 20555 Gentlemen:
Subject:
Docket No. 50-206 Standby Diesel Generators San Onofre Nuclear Generating Station Unit 1 By letter dated March 15, 1987, Southern California Edison (SCE) submitted for your review the results of our investigation of means to reduce transient torsional stresses on the crankshafts of the San Onofre Unit 1 standby diesel generators. Our conclusion was that modified automatic slow starts of the diesel engines for purpose of surveillance testing are cost effective and adequate to achieve the long term safety objectives. By letter dated July 15, 1987, the NRC staff requested further justification for this position. Specifically the NRC requested sufficient detail and explanation concerning the data and analyses methods used to support Imo Delaval's conclusions, so that an independent review of these analyses can be performed.
The enclosed report "Analysis of Various Modifications to the San Onofre Diesel Generators to Reduce the Potential of Fatigue Cracking in Crankshaft Oil Holes Due to Startup and Coastdown Transient Stresses", dated February 9, 1987, from Imo Delaval contains the information requested in your letter. It reviews the technical feasibility of various postulated modifications to the diesel generator system and includes estimates of cost and time (exclusive of SCE figures) to implement the three most feasible modifications, including "modified starts".
If you have any questions, please let me know.
Very truly yours, Enclosures cc: H. Rood, NRR Senior Project Manager
- 3. B. Martin, Regional Administrator, NRC Region V F. R. Huey, NRC Senior Resident Inspector, San Onofre Units 1, 2 and 3 D. E. Broeils, Duke Power, Delaval Diesel Generator Owners Group 8709280106 870918
. a PDR ADOCK 05000206 P