ML19269D150
| ML19269D150 | |
| Person / Time | |
|---|---|
| Site: | Trojan File:Portland General Electric icon.png |
| Issue date: | 02/09/1979 |
| From: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V) |
| To: | Goodwin C PORTLAND GENERAL ELECTRIC CO. |
| References | |
| NUDOCS 7902270386 | |
| Download: ML19269D150 (1) | |
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W ALNUT C RE EK, C ALIFOR NI A 94596 February 9, 1979 M
, j' q?!y Docket No. 50-344 m
c Portland General Electric Company 121 S. W. Salmon Street
- f Portland, Oregon 97204 Attention: Mr. Charles Goodwin, Jr.
Assistant Vice President Gentlemen:
This Information Notice is provided as an early notification of a li1 +
possibly significant matter.
It is expected that recipients will review the information for possible applicability to their facil-ities.
No specific action or response is requested at this time.
If further NRC evaluations so indicate, an IE Circular or Bulletin f
will be issued to recommend or request specific licensee actions.
If you have questions regarding the matter, please contact the Director of the appropriate NRC Regional Office.
ll;i ny:
Sincerely, fYJmcCG-R. H. Engelken Director
Enclosures:
1.
IE Information Notice No. 79-03 2.
List of IE Information Notices Issued in 1979 cc w/encls:
B. Withers, PGE F. C. Gaidos, PGE 79022703%6
s UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND Ef;FORCEMENT WASHINGTON, D.C.
20555 February 9, 1979 IE Information Notice No. 79-03 LIMIT 0P,QUE VALVE GFARED LIMIT SWITCH LUBRICANT Description of Circumstances:
At Commonwealth Edison reactors excessive failure rates of the Limitorque valve geared limit switches were being experienced.
Investigation revealed that the failure mode was a drying out and hardening of the Beacon 325 lubricant. Once hardening takes place, the brass gears within the limit switch become immobile and destroy themselves when an attempt is made to operate the valve.
The Limitorque Corporation has recommended Mobilgrease 28 as a replacement grease for switch applicatio!.
where the temperature exceeds 140 degrees Fahrenheit.
Tests conducted by Mobil and Limitorque Corporation indicate that Mobilgrease 28, in addition to having a superior temperature rating, will satisfy the same environmental conditions and meet the same qualification parameters as Beacon 325.
All licensee and construction pennit holders should consider conducting a review to determine if Beacon 325 lubricant is being used in geared limit switches in environments conducive to drying out and subsequent hardening of the lubricant.
If conditions are found to be conducive to failures, consideration should be given to replacing the grease with a more suitable grease.
This information is provided as an early notification of a possibly significant matter.
It is expected that recipients will review the information for possible applicability to their facilities.
No specific action or response is requested at this time.
If further NRC evalua-tions so indicate, an IE Circular or Bulletin will be issued to recom-mend or request specific licensee actions.
If you have questions regarding this matter, please contact the Director of the appropriate NRC Regional Office.
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