ML20072N043
| ML20072N043 | |
| Person / Time | |
|---|---|
| Site: | Bellefonte  |
| Issue date: | 03/23/1983 |
| 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 8304010435 | |
| Download: ML20072N043 (2) | |
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TENNESSEE VALLEY AUTHORITY V6FFhnen"ut' dim PfowePli "EA70$.,c7' March 23, 1983 NN BLRD-50-438/82-61 BLRD-50-439/82-54 U.S. Nuclear Regulatory Comission Region II Attn:
Mr. James P. O'Reilly, Regional Administrator 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30303
Dear Mr. O'Reilly:
BELLEFONTE NUCLEl.R PLANT UNITS 1 AND 2 - DESIGN BASIS FOR UNISTRUT INSTRUMENTATION HANGERS - BLRD-50-438/82-61, BLRD-50-439/82 FINAL REPORT The subject deficiency was initially reported to NRC-0IE Inspector D. Quick on August 23, 1982 in accordance with 10 CFR 50.55(e) as NCR BLN BLP 8224. This was followed by our first interim report dated September 22, 1982. Enclosed is our final report.
If you have any questions concerning this matter, please got in touch with R. H. Shell at FTS 858-2688.
Very truly yours, TENNESSEE VALLEY AUTHORITY L. M. Mills, Nanager Nuclear Licensing Enclosure cc:
Mr. Richard C. DeYoung, Director (Enclosure)
Office of Inspection and Enforcement U.S. Nuclear Regulatory Comissien Washington, D.C.
20555 8304010433 830323 PDR ADOCK 05000438 8
Ol'FICIAL COPY An Equal Opportunity Employer gy
I ENCLOSURE BELLEFONTE NUCLEAR PLANT UNITS 1 AND 2 DESIGN BASIS FOR UNISTRUT INSTRUMENTATION HANGERS NCR BLN BLP 8224 BLRD-50-438/82-61, BLRD-50-439/82-54 10 CFR 50.55(e)
FINAL REPORT Description of Deficiency Instrumentation lines at Bellefonte Nuclear Plant are supported by _
typical hangers ma6e from Unistrut components. Calculations to verify the seismic response and te assure that stress limits are not exceeded are not available. The design basis for the Unistrut typical instrument hangers is unverifiable and potentially unconservative.
i It has been determined that the cause of this deficiency is the failure to follow Division of Engineering Design (EN DES) engineering procedure (EP) 5.14 entitled " Vendor Documents - Handling and Dispositon" which cover the handling and disposition of vendor documents such as (a) design verification records (b) vendor instructions to TVA. This failure can be attributed to the individual (s) lack of understanding of this procedure.
Safety Implications The safety-related Unistrut instrumentation hangers may not be adequate for their design loading because their stress limits and seismic response cannot be verified. This could have resulted in the failure of these hangers due to overloading. This condition could have adversely affected l
the safe operation of the ;33nt.
Corrective Action A testing program for the Unistrut typical instrumentation tubing supports was performed at TVA's Singleton Materials Engineering Laboratory. Testing and analysis was in accordance with ASME Section III, Subsection NF 3260.
The support load capability in each orthogonal direction was determined by direct load application. Based on the experimentally determined load capabilities, an allowable support mass load was calculated such that allowable stress limits for the supports will not be exceeded. The results of this analysis had been tabulated on TVA drawings (series SGB0925-IO) and l
issued to TVA's Division of Constuction (CONST) for their information and use.
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As part of the ongoing construction process, all Unistrut typical instrumentation supports will be reviewed by TVA CONST to determine if the allowable support mass has been exceeded. Those hangers which exceed the allowable support mass will be reworked in accordance with the approved design drawings to make sure that the allowable limits are not exceeded.
l To prevent recurrence of this type of deficiency, the Manager of EN DES issued a management directive on February 26, 1982, which states that all individuals within EN DES are to be trained in those EPs which affect their work. Training for EP 5.14 was completed by all affected personnel during the month of December 1982.
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