ML20072F454
| ML20072F454 | |
| Person / Time | |
|---|---|
| Site: | Callaway  |
| Issue date: | 02/24/1983 |
| From: | Schnell D UNION ELECTRIC CO. |
| To: | Spessard R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| Shared Package | |
| ML20072F440 | List: |
| References | |
| ULNRC-610, NUDOCS 8303240213 | |
| Download: ML20072F454 (2) | |
Text
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e UNION ELECTRIC COMPANY 1901 GRATIoT STREET ST. Louis. MissouR umune Aooms.o DONALD F,.CHNELL P. O..OM 14.
February 24, 1983 m.....,,,
.r. lou,
,,..O Mr.
R.
L. Spessard, Director Division of Project and Resident Programs U.S. Nuclear Regulatory Commission Region III 799 Roosevelt Road Glen Ellyn, IL 60137 ULNRC-610
Dear Mr. Spessard:
INSPECTION REPORT NO. 50-483/82-10 This is in response to your letter dated November >3, 1982 requesting additional information regarding the testing of the Bunker Ramo 500 MCM EPA modules, which had exhibited fillet area cracks, to assure that they meet the original electrical and environmental design criteria requirements.
As previously reported, representative modules were subjected to x-ray analysis and helium leak rate testing.
This testing demonstrated no degradation in the pressure integrity of the modules from original factory specifications and IEEE-317-76 acceptance criteria.
Leak rate testing was the only testing conducted and was selected as the principal means of analysis because it was determined that pressure integrity was the only function of the modules which might potentially be compromised by the cracks.
This determination was the result of an engineering judgment by the equipment manufacturer and our Lead A/E.
The cracks are limited to the module fillet area (an area of rapid section change) with no axial penetration into the penetration seal area.
These cracks are considered to be surface imperfections.
Future propagation, if any, is not expected to occur into the seal area and therefore will not affect the electrical performance or seal integrity.
No electrical tests were considered necessary at the time of the initial investigation, as the only potentially impacted surface serves no electrical function.
Regarding any environmental impact of any future degradation, it is believed that these surface imperfections have not modified the component configuration or altered any performance characteristics and therefore have not impacted the equipment qualification.
These imperfections exist in areas which serve no pressure, electrical, or mechanical function.
Thermal aging of the cracks is expected to result, even in the 8303240213 830318 PDR ADOCK 05000483 c
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worst case, in a propagation which is not detrimental to the module performance.
All other environmental parameters will have no impact on the modules as a result of these cracks and therefore no testing other than that previously identified has been conducted.
Very truly yours, f;
=!
Donald F. Schnell JJS/ mal cc:
Mr.
H. M. Wescott NRC Resident Inspector Missouri Public Service Commission