ML19341A418
| ML19341A418 | |
| Person / Time | |
|---|---|
| Site: | Grand Gulf  |
| Issue date: | 01/16/1981 |
| From: | Mcgaughy J MISSISSIPPI POWER & LIGHT CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, AECM-81-33, NUDOCS 8101230482 | |
| Download: ML19341A418 (2) | |
Text
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!jl MISSISSIPPI POWER & LIGHT COMPANY
,M Helping Build Mississippi tahannhuand P. O. B O X 16 40, J AC K S O N, MIS SIS SIP PI 3 9 2 0 5 J^j, $ T 4G,7g f January 16, 1981 Office of Inspection & Enforcement T 't 7 p.
U. S. Nuclear Regulatory Commission j ',t p ; i
'W Region II 101 Marietta Street, N.W.
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Suite 3100 p, g
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Atlanta, Geort a 30303 i
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n Attention:
Mr. J. P. O'Reilly, Director
~ * '
Dear Mr. O'Reilly:
SUBJECT:
Grand Gulf Nuclear Station Units 1 and 2 Docket Nos. 50-416/417 i
File 0260/15525/15526 PRD-80/08, Final Report, Limitorque Valve Operator Halfunctions AECM-81/33
References:
- 1) AECM-80/74, 4/11/G0
- 2) AECM-80/165, 7/23/80
- 3) AECM-80/271, 11/3/80 On March 14, 1980, Mississippi Power & Light Company notified Mr. F. Cantrell, of your office, of a Potentially Reportable Defi-ciency (PRD) at the Grand Gulf Nuclear Station (GGNS) construction site. The deficiency concerns malfunctiorir.of Limitorque valve operators.
Our investigation has concluded that this deficiency is not reportable within the meaning of 10CFR50.55(e).
It has been deter-mined that this was an isolated incident on non-safety related equip-ment as is further explained in the attached final report.
Yours truly,
[p/ J. P. McGaughy, Jr.
CWH:mt g
Attachment cc:
Mr. N. L. Stampley M Victor Stello, Director Mr. G. B. Taylor Mr. R. B. McGehee Div. of Insp. & Enfer-
_nt South Miss. Electric Mr. T. B. Conner U. S. Nuclesr Reg. Comm.
Power Association i
Washington, D.C. 20555 P. O. Box 1589 Hattiesburg, MS 39401 1
810123oD66 nUP Member Middle South Utilities System 1
A Attachment to AECM-81/33
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~Page 1 of 1
]
FINAL REPORT FOR PRD-80/08 I.
Description of Deficiencv The concern involves Limitorque valve operators (type SMB) with
-valve stem protectors which are excessively threaded and may cause the valve to malfunction. When the valve is ;perated electrically, the stem protector acts as a jam-nut against the stem lock nut, which causes the to mue switch to trip the motor on high opening torque.
The valve suppliers fabricate and install the stem protectors on the Limitorque operators at their shop. The Constructor, in their coordination with the valve suppliers, determined that the stem protectors are designed to be hand tightened only when installed. The concern was identified en the condensate, feed-water and condensate cleanup systems during generic testing of non-safety related valves.
II.
Safety Implications As a result of testing, it was determined that the original problem identified was an isolated incident on non-safety rsla:cd equipment. Had it remained uncorrected, there would have been no adverse affect on the safety of plant operations throughout the expected lifetime of the plant.
Therefore, the condition does not meet the rerceting criteria of 10CFR50.55(e).
III. Corrective Actions Taken An investigation and evaluation of "Q Ialves with stem protectors was conducted to determine the effect on safety of operations.
The Constructor's Checkout and Turnover Organization (CTO) mechanical group tested fifty motor operated valves and determined that the,
identified condition had been an isolated incident. Details of the corrective action are available under the Constructor's Man-agement Corrective Action Report (MCAR) #65 at the GCNS site.
.