ML19345G193
| ML19345G193 | |
| Person / Time | |
|---|---|
| Site: | Humboldt Bay, Diablo Canyon |
| Issue date: | 03/02/1981 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Crane P PACIFIC GAS & ELECTRIC CO. |
| References | |
| NUDOCS 8103170023 | |
| Download: ML19345G193 (1) | |
Text
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o UNITED S1xTES
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NUCi. EAR REGUL ATORY COMMISSION g. - \\g' p/. C REGION V 0,
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1990 N. CALIFORNIA BOULEVARD o#
SulTE 202, WALNUT CREE K PLAZA
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..e WALNUT CREE K, CALIF 09NIA 94596 March 2, 1981 f
1 Docket Nos. 50-133, 50-275, 50 323 e' %,,
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MAi!0 5 Iggg w Pacific Gas and Electric Company P. O. Box 7442
\\ D San Francisco, California 94106 Attention: Mr. Philip A. Crane, Jr.
A<sistant General Counsel Gentlemen:
The encloseo circular is forwarded for your information.
No writt0r. response to this circular is required.
If you have any questions related tc this matter, please contact this office.
Sincerely, R. H. Engelken Director
Enclosure:
l l
1.
IE Circular No. 81-03 2.
List of IE Information l
Notice Recently Issued cc w/ enclosures:
l J. D. Shiffer l
W. P.aymond, PG&E l
R. C. Thornberry, Plant Manager E. Weeks, PG&E, Huu.boldt Bay l
E. B. Langley, Jr., PG&E l
l l
70 g g
SSINS No.:
6820 Accession No.:
8005050075 IEs 81-01 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT W/ SHINGTON, D.C.
20555 January 27, 1981 IE Bulletin No. 81-01:
SURVEILLANCE OF MECHANICAL SNUBEERS Description of Circumstances:
Several instances of failures of mechanical snubbers supplied by International Nuclear Safeguards Corporation (INC) have been identified that indicate possible deficiencies in these snubbers. A summary of the failures that have occurred is provided below:
1.
On August 9, 1974, the Tennessee Valley Authority submitted event report BFAO-50-260/741W identifying 11 of 14 INC Model MSVA-1A snubbers that were found inoperable on Browns Ferry Nuclear Power Station Unit 2 and subsequently identified 5 of 14 inoperable units on Browns Ferry Nuclear Power Unit No 3.
All of these units were found to be frozen, and the cause was attributed to a failure to lubricate the parts during assembly.
The failed snubbers were replaced with new units produced by the same manufacturer.
2.
On npril 12, 1976, the St. Lucie Plant Unit 1 facility of Florida Power and Light Ccrporation submitted event report No. 50-335-76-9 wherein five INC Model liSVA-1 snubbers were identified as inoperable because they were found to be frozen. The failures were caused by oxidation on the internals and by. improper assembly. All.INC. mechanical snubbers _were replaced with units produced by another manufacturer.
3.
On April 8, 1977,' Iowa Electric Light L.1d Power Company submitted event report No. 77-23 for the Duane Arnold Energy Center facility that iuenti-fied 13 INC Model IMSVA-1 Type AS snubbers to be frozen; the cause of failure was attributed to large amounts of interior oxidation.
The units were replaced with those produced by another manufacturer.
4.
On December 5, 1979, personnel from the Nuclear Regulatory Commission visited Department of Ener;g (00E) facilities at Richland, Washington, to obtain information on DOE experience with INC snubbers at the Fast Flux Test Facility (FFTF). The DOE-owned FFTF was equipped with more than 4,000 mechanics 1 pipe restraints (snubbers) supplied by INC.
In 1978,
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FFTF examined more than 0;;
from their installation and M DUPLICATE DOCUMENT were frozen. The plant was JN seen no service and had bee Entire document previously environments for 1 to 2 yea entered into system under:
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