ML19269D134
| ML19269D134 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 02/09/1979 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Bryan J UNION ELECTRIC CO. |
| References | |
| NUDOCS 7902270369 | |
| Download: ML19269D134 (1) | |
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.379 Docket No. 50-483 Docket No. 50-486 Union Electric Company ATTN:
Mr. John K. Bryan Vice President - Nuclear P. O. Box 149 St. Louis, MO 63166 Centlemen:
This Information Notice 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 facili-ties.
No specific action or response is requested at this time.
If further NRC evaluations so indicate, an IE Circular or Bulletin 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.
Sincerely, Q ks_'fler' $%
vJames G. Kep Director
Enclosures:
1.
IE Information Notice No. 79-03 2.
List nf IE Information Notices Issued in 1979 cc w/encls:
Mr. W. H. Weber, Manager, Nuclear Construction Central Files Director, NRR/DPM Director, NRR/ DOR PDR Local PDR NSIC TIC Region I & IV Ms. K. Drey Hon. C. J. Frass, Chairman Missouri Public Service Commissien 79022703D:
A U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFnRCEMENT RECION III February 9, 1979 IE Information Notice No. 79-03 LIMITORQUE VALVE GEARED 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 Jeacon 325 lubricant. Once hardening takes place, the brass gear-within the limit switch become immobile and destroy themselves wh an attempt is made to operate the valve.
The Limitorque Corporation has recommended Mobilgrease 28 as a replacement grease for switch applications where the temperature exceeds 140 degreet Fahrenheit. Tests conducted by Mobil and Limitorque Corporation indicate that Mobilgrease 28, in addition to having a superior te=perature rating, will satisfy the same environmental conditions and meet the same qualification parameters as Beacon 325.
All licensee and construction permit 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 notificatico 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.
Enclosure:
List of IE Information Notices Issued in 1979 bOft 7902150358
IE Information Notice No. 79-03 February 9, 1979 LISTING OF IE INFORMATION NOTICES ISSUED IN 1979 Information Subject Date Issued To Notice No.
Issued 79-01 Bergen-Paterson Hydraulic 2/2/79 All power reactor Shock and Sway Arrestor facilities with an OL or a CP 79-02 Attempted Extortion -
2/2/79 All Fuel Facilities Low Enriched Uranium