ML20009B991
| ML20009B991 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 06/16/1981 |
| From: | Nunn D SOUTHERN CALIFORNIA EDISON CO. |
| To: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, NUDOCS 8107200125 | |
| Download: ML20009B991 (1) | |
Text
Docket Nos. 50-361/352 Southern California Edison Company gE P. O BOX 800
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2 244 W ALNUT GROVE AVENUE ROSEME AD. C ALIFORNI A 91770 7
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June 16, 1981 d
Mr. R. H. Engelken, Director d
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Office of Inspection and Enforcement s
0(a3,[1'h U. S. Nuclear Regulatory Commission t-J Region V f
Suite 202, Walnut Creek Plaza
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v 1990 North California Boulevard S
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Walnut Creek, California 94506 f
JUL 171981 > '"
Dear Mr. Engelken:
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Subj ect:
Docket Nos. 50-361 and 50-362 San Onofre Nuclear Generating Station, 3
By letter dated May 26, 1981 we notified you of a condition discovered in construction which we considered to be potentially reportable in accordance with 10CFR50.55(e).
The condition concerned the separation of a blade from a CEDM cooling fan which was due to a fatigue crack in the area of a casting flaw at the stressed surface of the blade.
The CEDM cooling 1. nit in which the blade failure occurred is a non-safety related component.
However, since there are safety related fans of a similar design, a detailed investigation was performed to determine whether the failure was of a generic nature.
The investigation established that the failure was due to a unique combination of fan configuration and loading which caused a cyclic loading of the blades.
All other non-safety related CEDM fans have been examined for cracks and the problem will be resolved by resetting the blade angle.
No action is required on the safety related fans.
It is concluded that no significant deficiency exists in the safety related fans and this condition is r.ot reportable in accordance with 10CFR50.55(e).
If you have any questions regarding this matter we would be pleased to discuss them with you at your convenience.
Sincerely, gg
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40 cc:
Dr. L. T. Papay R. J. Pate (NRC, San Onofre Units 2 ana 3) 8107200125 810616
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