ML20076G433
| ML20076G433 | |
| Person / Time | |
|---|---|
| Site: | Summer  |
| Issue date: | 04/22/1983 |
| From: | Dixon O SOUTH CAROLINA ELECTRIC & GAS CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| IEB-81-01, IEB-81-1, NUDOCS 8306140670 | |
| Download: ML20076G433 (4) | |
Text
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SOUTH CAROLINA ELECTRIC & GAS COMPANY Post omCu tu COLuustA. south CAmoWNA 29218 0.W.OfxON,JR.
VICE PREsiotNT NUCLE Am oreRATION:
April 22, 1983 w
Cd r
Mr. James P. O'Reilly, Regional Administrator
^
3, U. S. Nuclear Regulatory Commission u
Region II - Suite 2900
- b 101 Marietta Street, N. W.
S8 Atlanta, Georgia 30303 23 4
Subject:
VirgilC.SummerNuclearSta[fon Docket No. 50/395 OperatingLicenseNo.NPF-1f)$
Dear Mr. O'Reilly:
This letter is a follow-up to our letter of June 22, 1982 concerning IE I
The June 22 letter informed you of the IEB 81-01 inspection results for safety-related snubbers and reported the frozen snubbers uader the provisions of 10CFR50.55e. The snubbers, which were found to be inoperable as a result of the inspection, were listed in the letter.
It was stated in the letter that these inoperable snubbers were being returned to the manufacturer for evaluation and repair. The manufacturer was to prepare a report identifying the mode of failure for each of the inoperable snubbers. The letter stated further that we would provide a final report to the Commission identifying cause and corrective action once the manufacturer's report was received.
We have received the manufacturer's report for the inoperable snubbers. The purpose of this letter is to provide you with the probable cause of failure along with our corrective action for each of the inoperable snubbers.
Snubbers examined and tested as required by the bulletin were manufactured by Pacific Scientific. All safety-related mechanical snubbers at Virgil C.
Summer Nuclear Station were furnished by this manufacturer. The snubbers which were found to be inoperable are listed in Attachment I along with the probable cause of failure for each as determined by the manufacturer. An explanation of each of the failure modes along with our corrective action for each type of failure is given in the discussion that follows.
Five (5) PSA-\\ snubbers, one (1) PSA-snubber, and one (1) PSA-3 snubber were determined by the manufacturer to have a probable failure caused by improper installation. The manufacturer specifically stated that the snubbers appeared to have been twisted. Our present procedures have a caution against twisting. Our corrective action for this will be to strengthen this caution in the procedures dealing with snubber removal and installation.
Four (4) PSA-k snubbers and five (5) PSA-snubbers were determined by the j
manufacturer to have a probable failure caused by overloading. The 8306140670 830422
~
gDRADOCK 05000395 p TEIl
a us Mr. James P. O'Reilly Page 2 April 22, 1983 f
manufacturer specifically noted that damages to internal parts tend to support direct (pin-to-pin) loading. There were also dents on some of the external parts, the cause of which could not be determined. There is no evidence to indicate that the overloads could have been caused by improper system operation.
South Carolina Electric & Gas Company (SCE8G) has determined that the probable cause of the overloading was mishandling, and/or abuse during construction. The external dents support this cause.
It should be noted that the load rating of these snubbers is relatively low (350 lbs. and 650 lbs.),
and that the snubbers could readily be overloaded above these values if they were not handled or treated properly. Our corrective action for this will be i
to add a special caution in the procedures dealing with snubbers to avoid abusing or manhandling snubbers, paying particular attention to the smaller ones.
Two (2) PSA-3 snubbers were determined by the manufacturer to have a probable failure caused by mishandling. This is another type of installation / removal problem. Our corrective action for this is the same as for the snubbers with installation problens.
The remainder of-the snubbers listed in the attachment were found to be functionally acceptable when tested by the manufacturer. No further action is required for these.
It is apparent that the basic reason for these frozen snubbers centers on improper handling. Our corrective action for this will be to attempt to better indoctrinate personnel in the proper handling of snubbers when they work with or around them. The actions outlined in this letter for procedure revisions should accomplish this objective for those people who work with the snubbers.
In order to better educate the people who. work around snubbers, their supervisors will indoctrinate them in the necessity of exercising care not to abuse or mishandle snubbers. We anticipate that the corrective actions outlined in this letter will be complete by June 30, 1983.
4 l
This is our final report on this matter. If there are any questions, please advise.
. Ve.
rul you O. W. D on, J.
JKT:0WD:glb Attachment cc: Page 3
_)
s Mr. James P. O'Reilly Page 3 April 22, 1983 cc:
V. C. Summer T. C. Nichols, Jr./0. W. Dixon, Jr.
E. C. Roberts H. N. Cyrus Group / General Managers
- 0. S. Bradham M. D. Quinton R. B. Clary G. D. Moffatt C. A. Price P. Fant A. R. Koon D. A. Lavigne J. Turkett J. K. Todd C. L. Ligon (NSRC)
G. J. Braddick J. C. Miller J. L. Skolds J. B. Knotts, Jr.
I&E (Washington)
Document Management Branch NPCF File (Lic./Eng.)
./
u.
d Attachment I Snubber Serial No.
Podel/ Size Load (lb.)
Failure Probable Cause CSH-1262 7807 PSA-k 350 Frozen Installation RHH-038 1171 PSA-k 350 Frozen Overload CSH-4009 2391 PSA-k 350 Frozen Installation CSH-4014 13831 PSA-k 350 Frozen Acceptable
- CSH-952A 3723 PSA-k 350 Frozen Installation BDH-044 1248 PSA-k 350 Frozen Overload RHH-054 3730 PSA-k 350 Would overload Not Engage j
SIH-1343 15574 PSA-k 350 Frozen Overload ASH-079 3628 PSA-k 350 Frozen Installation MSH-226 11967 PSA-k 350 Frozen Installation MSH-202 1142 PSA-650 Frozen Overload SIH-095 865 PSA-650 Frozen Overload CSH-156 2318 PSA-650 Frozen Installation CSH-765 1039 PSA-650 Frozen Overload BDH-038 2213 PSA-650 Frozen Overload BDH-042 2209 PSA-650 Frozen Overload RCH-044 2653 PSA-1 1,500 Frozen Acceptable
- RCH-4006 8705 PSA-1 1,500 Frozen Acceptable
- RHH-163 1507 PSA-3 6,000 Frozen Mishandling SPH-116 700 PSA-3 6,000 Frozen Acceptable
- CCH-121 2335 PSA-3 6,000 Frozen Installation SIH-062 2062 PSA-3 6,000 Frozen Acceptable
- RHH-228 727 PSA-3 6,000 Frozen Mishandling FWH-173 1632 PSA-10 15,000 Frozen Acceptable
- SIH-415 4923 PSA-35 50,000 Frozen Acceptable *
- These units were tested and found to be functionally acceptable by the manufacturer.
J