ML20063L861
| ML20063L861 | |
| Person / Time | |
|---|---|
| Site: | Wolf Creek, Callaway, 05000000 |
| Issue date: | 09/03/1982 |
| From: | Petrick N STANDARDIZED NUCLEAR UNIT POWER PLANT SYSTEM |
| To: | Jay Collins, James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III), NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, SLNRC-82-035, SLNRC-82-35, NUDOCS 8209090251 | |
| Download: ML20063L861 (2) | |
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SNUPPS Standardized Nuclear Unit Power Plant System 5 Choke Cherry Road Nicholas A. Petrick Rockville, Maryland 20850 Executive Director (301) 869-8010 September 3, 1982 SLNRC 82- 035 FILE:
0491.10.2 SUBJ:
Interim Report: Limitorque Operators - Sheared Pinion Keys; 10 CFR 50.55(e) Report 82-1 Mr. James G. Keppler A&ninistrator, Region III U. S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137 Mr. John T. Collins Administrator, Region IV U. S. Nuclear Regulatory Commission Suite 1000, Parkway Central Plaza Arlington, Texas 76012 Docket Nos. STN 50-482 and STN 50-483
Reference:
Westinghouse (Rahe) Letter, NS-EPR-2637, to NRC (DeYoung),
dated 8/6/82 Gentlemen:
On August 4,1982, SNUPPS informed the Nuclear Regulatory Commission, Regions III and IV, of a potential deficiency involving sheared pinion keys in Limitorque motor operators.
The information was communicated by telephone to Mr. J. Konklin (Region III) and Mr. J. Jaudon (Region IV) pursuant to 10 CFR 50.55(e).
The NRC was also informed of this issue on a generic basis by the referenced letter.
Sheared pinion keys were found on six Limitorque SB-0-25 motor operators during inspections at plants other than Wolf Creek and Callaway.
The pinion key secures the motor pinion gear to the motor shaft.
Wi thout this connection the motor operator would not operate the valve and could, depending on the valve's function, cause a potential safety problem.
A metallurgical evaluation of the f ailed pinion keys indicated that they were made of a low carbon steel rather than a hardened alloy.
Westinghouse, the valve supplier, was unable to obtain suf ficient infor-mation regarding the type of material used for pinion keys in motor operators supplied by Limitorque other than model SB-0-25.
Therefore it is possible that other models of Limitorque motor operators could be affected.
8209090251 820903 PDR ADOCK 05000482 S
PDR Wfk
4 s
SLNRC 82-Page 2.
IE Information Notice 81-08 dealt with the failure of motor-to-shaft keys in Limitorque model SMB-4 operators.
As a result of this Notice and correspondence from Limitorque, the SNUPPS Utilities identified several valves that should have the pinion keys replaced.
These changes involved SMB-3, 4, and 5 operators with torque exceeding 150 foot-pounds and were associated with non-safety related valves in the SNUPPS design.
The SNUPPS Utilities are developing a plan to resolve this concern for all valves with Limitorque operators.
Follow-up reports will keep the NRC informed regarding the actions taken by the SNUPPS Utilities relative to this matter. A followup report will be submitted by March 3,1983.
Very truly yours, a.
g Nicholas A. Petrick RLS/nld cc:
G. L. Koester KGE D. T. McPhee KCPL D. F. Schnell UE T. H. Vandel NRC/WC J. Konklin NRC-Region III J. H. Neisler NRC/ CAL Record