ML20054G442
| ML20054G442 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 06/15/1982 |
| From: | Adam Wilson HENRY PRATT CO. |
| To: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| References | |
| REF-PT21-82-662-000 PT21-82-662, PT21-82-662-000, NUDOCS 8206210557 | |
| Download: ML20054G442 (2) | |
Text
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HENRY PRNITF COMPANY
( t-( u tt ive ( 11gil u 'erir ig f() flt ii(1 systel11s
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4 fluclear Regulatory Commission go Region 3 Office 799 Roosevelt Road Glen Ellyn, Illinois 60137 Attn; Mr. James G. Keppler, Director Office of Inspection and Enforcement
Subject:
fion-compliance Reporting Under 10CFR, Part 21 Section 206 of Energy Reorganization Act of 1974.
Dear Mr. Keppler:
Subsequent to a telephone report made to your Mr. Ray Priebe, (Washington Duty Officer) on Friday, June 11, 1982 by the writer, this letter is presented in triplicate, with the following:
Project Involved:
Mississippi Power & Light Grand Gulf Nuclear Station Unit #1 & #2 Equipment:
Pneumatic actuators furnished with Pratt 24" Butterfly Valves.
Equipment
Description:
Pneumatic Actuator Models T316 and T312 manufactured by G. H. Bettis Corporation, Houston Texas, furnished with 24" Butterfly Valves manufactured by Henry Pratt Company, Aurora, Illinois.
Equipment Identification:
Pratt Orders: D-0084-1 (4 valves); D-0073-1 (4 valves) and D-0038-2 (6 valves).
Time and Date Pratt infonned of defect:
-2:00 p.m.
Wednesday, June 9,1982.
Defect evaluated and determined to be reportable by Pratt/Bettis June 11, 1982.
8206210557 820615 PDR ADOCK 05000416
- - - OJn,qt9,4 JUN 1 6 M S
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.4 Nuclear Regulatory Conmission e
June 15, 1982 Page How Non-compliance detected:
During Grand Gulf Plant system test, valve actuator appeared to have excessive vibration. Upon inspection, Yoke of actuator was found to be broken. Upon further inspection of 2 or 3 similar actuators, Yokes were found to be cracked.
Description of Non-compliance:
Bettis Model T (or NT) Series actuator Yokes with 3/8" deep keyway and 3" diameter shaft bore appear to have insufficient remaining wall thickness for full range torques. When actuator operates, the Yoke which is coupled to the valve shaft by a key may be over-stressed resulting in Yoke failure at the keyway and rendering the valve inoperable.
The problem is believed limited to one valve / actuator combination; namely, 24" Pratt Butterfly Valve with 3" diameter shaft / G.H. Bettis Model T (or NT) 300 Series pneumatic actuators.
Similar equipment in service:
Henry Pratt Company is searching its files to identify projects where such equipment may have been delivered and will thereafter report these to your offices and any affected utilities. This report will be made by June 18, 1982.
Corrective Action:
Grand Gulf Project has notified the G. H. Bettis Corporation of the defect and has asked Bettis to determine how and when they can replace the defective parts. A total of 14 new Yokes and keys with keyway modifications are being furnished to Grand Gulf by G. H. Bettis.
Very truly yours, d/. 2 M
A. K. WILSON Vice President Manager of Engineering AKW:pst CC:
B. R. Cummins R. D. Nelson G. A. Kurkjian H. C. Schwenk T. Berg
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