ML20076D765
| ML20076D765 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 05/18/1983 |
| From: | Mills L TENNESSEE VALLEY AUTHORITY |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| 10CFR-050.55E, 10CFR-50.55E, NUDOCS 8305230565 | |
| Download: ML20076D765 (2) | |
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s TENNESSEE VALLEY AUTHORITY CH ATTANOOGA. TENNESSEE 37401 400 Chestnut Street Tower II co cA May 18, 1983 3
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$m9 BLRD-50-439/82-53 P
CD 00 A
U.S. Nuclear Regulatory Connission
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Region II Attn: Mr. James P. O'Reilly, Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30303
Dear Mr. O'Reilly:
BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 - USE OF FILLET WELDS ON PIPING LUGS
- BLRD-50-438/82-59, BLRD-50-439/82 FINAL REPORT The subject deficiency was initially reported to NRC-0IE Inspector R. V.
Crlenjak on August 19, 1982 in accordance with 10 CFR 50.55(e) as NCR GEN CEB 8209 This was followed by our interim reports dated September 20, 1982 and January 19 and March 15, 1983 Enclosed is our final report. A final report was submitted separately on this NCR for the Watts Bar Nuclear Plant.
If you have any questions, please get in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY L. M. Mills, nager Nuclear Licensing Enclosure cc: Mr. Richard C. DeYoung, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.
20555 Records Center (Enclosure)
Institute of Nuclear Power Operations 1100 Circle 75 Parkway, Suite 1500 Atlanta, Georgia 30339 YO
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PDR OfY gg.27 An Equal Opportunity Employer
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ENCLOSURE BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 USE OF FILLET WELDS ON PIPING LUGS BLRD-50-438/82-59, BLRD-50-439/82-53 10 CFR 50.55(e)
FINAL REPORT Description of Deficiency Fillet welds have been used to attach lugs to piping at Bellefonte. These lugs are permanent integral e ttachments.on mechanical piping and are desjened to provide support or to retain movement axially or laterally. At Bellefonte, the lugs were designed by both ITT Grinnel and TVA. While use of fillet welded lugs is allowed by the ASME Code,TVA's Civil Engineering Support Branch was concerned that TVA had no specific design document to qualify piping with fillet welded lugs and that their design document, CL3 report 76-20, was being used even though it requires the use of full penetration welds.
Safety Implications As noted below, no safety implication exists for previously installed fillet-welded lugs.
However, if this situation hsd remained uncorrected, use of CEB* report 76-20 in the future design of fillet > welded lugs intended for use with safety-related piping could produce larger piping stresses than those: for which the piping was being designed. This could cause the pipe to fail, which in turn could adversely affect safe operation of the plant.
Corrective Action Vendor-designed fillet-welded lugs are adequate as is, and TVA-designed fillet-welded lugs were limited to rigorously analyzed piping two inches or less in diameter and for various alternately analyzed piping. In all such cases, TVA has determined that the strew nargins in UEB report'76-20 exceed the additional design stresses required by the use of. the fillet-welded lugs, and that these lugs are acceptable as is. The calculation package for thess lugs is complete and procedures for designing fillet-kelded lugs for Bellefonte have been incorporated into DIM-N4-50-D717-4.
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