ML20030C499
| ML20030C499 | |
| Person / Time | |
|---|---|
| Site: | San Onofre  |
| Issue date: | 07/21/1981 |
| From: | Papay L SOUTHERN CALIFORNIA EDISON CO. |
| To: | Engelken R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| References | |
| 10CFR-050.55E, NUDOCS 8108260168 | |
| Download: ML20030C499 (3) | |
Text
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50.55(e) Report I
Docket Nos. 50-361/362 Southem Califomia Edison Company gE R O. BOK 800 2244 WALNUT GROVE AVENUE ROSEMLAD, CALIFORNIA 91770 p,,y veCE PnEsiorset 213 S72-44'4 July 21, 1981 h p,[ygM p Mr. R. H. Engelken, Director
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Suite 202, Walnut Creek Plaza 1990 North California Boulevard Qf Walnut Creek, California 94596 Dest Mr. Engelken:
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Docket Nos., 50-361 and 50-362 San Ow fre Nuclear Generating Station, Units 2 and 3 In a letter to your office dated June 23, 1981, we identified a condition which we consider reportable in accord-ance with 10CFR50.55(e).
The condition involves improper assembly of coaxial connectors in electrical containment pene-trations.
Enclosed in accordance with 10CFR50.55(e) are twenty-five (25) copies of a Final Report entitled, " FINAL REPORT ON THE IMPROPER ASSEMBLY OF COAXIAL CONNECTORS IN ELECTRICAL CON-TAINMENT PENETRATIONS, San Onofre Nuclear Generating Station, Units 2 and 3."
If you have any questions regarding this report, we would be pleased to discuss this matter with you at your con-venience.
Very truly yours, W
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Victor Stello (NRC, Director I&E) j R. J. Pate (NRC, San Onofre Units 2 and 3) gf
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FINAL REPORT ON THE IMPROPER ASSEMBLY OF COAXIAL CONNECTORS IN ELECTRICAL CONTAINMENT PENETRATIONS San Onofre Nuclear Generating Station, Units 2 end 3 INTRODUCTION This report is submitted pursuant to 10CFR50(a)(3).
It describes a condition discovered during construction in which coaxial con-nectors in Westinghouse Elec trical Containment Penetrations were improperly assembled.
This report includes a description of the deficiency, analysis of the safety implications and a summary of the corrective actions taken.
By letter dated June 22, 1981, Edison confirmed notification to the NRC of this potentially reportable condition.
BACKGROUND During an investigation of vendor installed series N coaxial connectors located in the Unit 2 Electrical Containmenc Penetra-tions, copper wire rings (18 gage) were found in the female jack connectors, apparently being used as spacers.
This provided inconsistent clearance between the face of the connector jack and the end of the center conductor female contact, resulting in a mating problem between the connector jack and plug.
Non-conformance reports for Units 2 and 3 were issued to correct the assembly interference that existed between the center female conductor pin and the face of the connector jack.
In the process of implementing the disposition of the nonconformance reports, the additional conditions of improper assembly which are noted below were discovered.
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DIS CUSS'GN l
The following discussion is responsive to 10CFR30.55(e)(3).
Description of t e Deficiency h
Vendor installed series N female jack coaxial connectors in fourteen (14) electrical penetrations were found to contain ccpper wire spacers.
In addition, the female connector jacks containing the copper wire spacers did not have the cable jacket / insulation flush with the shield spreader detent.
This condition is not in accordance with Westinghouse Electric Cor-poration Specification E-40152, Assembly Instructions - Series N Coaxial Connectors.
Field repairs of the connectors were
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Page Two FINAL REPORT ON THE IMPROPER ASSEMBLY OF COAXIAL CONNECTORS IN ELECTRICAL CONTAINMENT PEhTTRATIONS San Onofre Nuclear Generating Station, Units 2 and 3 performed in accordance with Westinghouse provided criteria.
Subj ect to the repair work it was determined that no accept-ance criteria had been provided for soldering of the connectors.
Analysis of Safety Implications h
Stress capability is provided by the cable jacket fitting snugly within the clamp detent and by the pressure that the gasket exerts on the jacket.
In the present condition the stress is placed directly on the shield which can cause shield damage.
Since the copper spacers were not designed for any application within the connector, a loosening could occur and could lead to the loss of electrical continuity.
These connectors are used for all channels of the safety related ex-core instrumentation as well as containment area radiation monitors.
CORRECTIVE ACTION A general procedure and acceptance criteria document (Procedure Change Notice to Quality Control Instruction No. 605) has been prepared for use wherever field soldering is performed.
A general review of the application of field soldering has been initiated.
This will include reinspection, as required, of safety related field soldering, using the acceptance criteria of QCI-605.
Any soldering found to be deficient will be reworked.
All Series N coaxial connectors on the Electrical Containment Penetrations listed on Nonconformance Reports E-582 and E-2246 will be reworked by field personnel in accordance with Westing-house Specification E-40152.
All reworked connectors will be reinspected by Bechtel Quality Control prior to reinstallation, using the acceptance criteria of QCI-605.
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