ML20010C108
| ML20010C108 | |
| Person / Time | |
|---|---|
| Issue date: | 08/12/1981 |
| From: | Agee J, Mcdonald D, Reinmuth G NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV), NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| Shared Package | |
| ML20010C100 | List: |
| References | |
| REF-QA-99900901 NUDOCS 8108190128 | |
| Download: ML20010C108 (3) | |
Text
U.S. NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT Docket No.:
99900901/81-02 Environmental Qualification Program:
Independent Ve.ification Test No. 4 Report No. 2 Preliminary Report of D. G. O'Brien, lype K, Electrical Penetration Assembly (EPA) Failures During Verification Test Equipment Identification:
Test Specimen:
EPA Type:
K Instrumentation Penetration Mfg.:
D. G. O'Brien Equipment Spec. No.:
Duke Power Company CNS-1361.00-00-0003 Serial No.:
4986-F Lot 1216K Test Organization:
Sandia National Laboratories, Albuquerque, New Mexico 87185 Contract No.:
83101 Inspection Conducted: June 22-26, 1981 Staff:
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gRegionIVR. Age &( Equipment Qualification Engineer, Daic
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D. ~G. Mcdonald, NRC' Cbnsultant, Los Afanios Date National Laboratory Approved By:
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G. W. Reinmuth, Chiet Vendor and Special Date Projects Branch, IE Summary:
The purpose of this inspection was to obtain information relative to the failure mechanism and the specific cause of the failures.
Results:
The review performed during this inspection indicates:
1.
The failure mechanism was identified as the extrusion of the grommet material.
2.
The cause of the failure was the confinement of the grommet material in the assembled EPA and the elevated temperatures during the accelerated aging portion of the test.
8108190128 810814 PDR GA999 EXISANL
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99900901 PDR
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Details Section Prepared By:
J. R. Agee and D. G. McDoncld A.
Persons Contacted L. L. Bonzon - Sandia National Laboratory (SNL)
W. H. Buckalew - SNL D. Jeppesen - SNL E. A.-Salazar - SNL F. V. Thome - SNL P. M. McBride - Duke Power Company (DPC)
G. C. Rogers - DPC H. P. Hilbert - D. G. O'Brien, Inc.
R. J. Flaharity - Life Cycle Engineering E. Walton - Brand Rex Cable Co.
P. K. Das - Brand Rex Cable Co.
B.
General The purpose of the subject test was to expose a D. G. O'Brien, Type K Instrumentation EPA to a complete environmental qualification test program in accordance with IEEE 323-1974 and NUREG-0588.
The test specimen (EPA) included crosslinked polyethelene (XLPE) cables, D. G. O'Brien connectors and a junction box.
This test program was performed by SNL for the NRC and was conducted in accordance with the " Connector Assembly Test Plan for Duke Power, Catawba 1 and 2 Connectors," Fourth Draft, dated January 30, 1981.
The purpose of this inspection was:
1.
To assist SNL in devising a disassembly procedure for the test specimen to identify, isolate and determine the cat.3e of the failures identified during the test.
2.
To verify proper implementation of the procedure by SNL.
3.
To provide a preliminary description of the failures.
This effort was accomplished and documented in a memorandum " Preliminary Assessment of D. G. O'Brien, Type K, Electrical Penetration Assembly (EPA)"
to W. R. Rutherford from J. R. Agee and D. G. Mcdonald, dated June 26, 1981.
This memorandum is included as Enclosure 1 and Enclosure 2 provides copies of pictures taken during the disassembly of the EPA.
C.
Findings Based on the details provided in Enclosure 1, it was determined that the cause of failure was the extrusion of the cable grommet material which resulted in weak insulation points or bare wires in the cable conductors near the brass plug sleeve.
The cable grommet material is a Dow Corning Company, Siligard 170 silicone RTV.
Extrusion of the material was
. _ _ _ - _. l attributed to confinement in the assembled EPA which did not allow for thermal expansion during exposure to sustained elevated temperatures during the accelerated thermal aging process.
IE Information Notice No. 81-20 " Test Failures of Electrical Penetration Assemblies," dated July 10, 1981, provides additional details.