ML19343B884
| ML19343B884 | |
| Person / Time | |
|---|---|
| Site: | Seabrook  |
| Issue date: | 01/27/1981 |
| From: | Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| To: | Tallman W PUBLIC SERVICE CO. OF NEW HAMPSHIRE |
| References | |
| NUDOCS 8102180122 | |
| Download: ML19343B884 (1) | |
Text
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jo UNITED STATES g
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2 e REGION I g
NUCLEAR REGULATORY COMMISSION o, 'g\\
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631 PARK AVENUE
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KING OF PRUSSIA, PENNSYLVANIA 19406 i
3 JAN 2 71981 Docket Nos. 50-443 4
50-444
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Public Service Company of New Hampshire
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ATTN:
Mr. W. C. Tallman e
Chairman and Chief Executive Officer
.l 2
1000 Elm Street Manchester, New Hampshire 03105 Gentlemen:
The enclosed IE Bulletin No. 81-01, " Surveillance of Mechanical Snubbers," is forwarded to you for information.
No written response is required.
If you desire additional information regarding this matter, please contact this office.
Sincerely,
(
Boy e H. Grier Director
Enclosures:
1.
List of Recently Issued Bulletins CONTACT:
D. L. Caphton (215-337-5266) cc w/encls:
John DeVincentis, Project Manager s
8102180 h
l SSINS No.:
6820 Accession No.-
8005050075 UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.
20555 IE Bulletin No. 81-01 January 27, 1981 Page 1 of 7 SURVEILLANCE OF MECHANICAL SNUBBERS 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 fcund 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 j
manufacturer.
2.
On April 12, 1976, the St. Lucie Plant Unit 1 facility of Florida Pcwer and Light Company submitted event report No. 50-335-76-9 wherein five INC Model MSVA-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 and Power Company submitted event report No. 77-23 for the Duane Arnold Energy Center facility that identi-fied 13 INC Model 1MSVA-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 l
visited Ocpartment of Energy (00E) facilities at Richland, Washington, to l
obtain information on DOE experienca
~
Test Facility (FFTF).
The DOE-owned 4,000 mechan cal pipe restraints (sn DUPLICATE DOCUMENT i
FFTF examined more than 800 of these Entire document previously entered into system under:^
bDYO$b 75 ANO No. of pages:
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