ML20010E911

Final Deficiency Rept Re Socket Weld Misalignment on Essential Air Sys Welds,Initially Reported on 800930.Welding Procedure G-29M Revised to Provide More Reasonable Requirements for Socket Weld Engagement

ML20010E911
Person / Time
Site:	Bellefonte
Issue date:	08/31/1981
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, NCR-1267, NUDOCS 8109090096
Download: ML20010E911 (2)

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- TENNESSEE VALLEY AUTHORITYUS?lpd p* <n

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CH ATTANOOGA. TENNESSEE 374of "/,=!..

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- ul.,, S E o 3 n *u. I u L- August 31, 1981 ,

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i. -Mr. James _P. O'Reilly, Director

.L Office of Inspection .and Enforcement . k(,

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U.S. Nuclear Regulatory Commission

[.A Region II-- Suite 3100. f. SEP 0 81981 > -n

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! Atlanta, Georgia 30303 9 p

Dear.Mr. O'Reilly:

. sg BELLEFONTE NUOLEAR PLANT UNITS 1 AND 2 - SOCKET WELD MISALIGNMENT ON

[- ESSENTIAL. AIR SYSTEM WELDS - NCR 1267 - FINAL REPORT l

The . subject nonconformance was initially reported to NRC-0IE Inspector

'R. W. Wriglit' on September 30, 1980, in accordance with 10 CFR Part 50.55(e). This was followed by.our interim reports dated October 29 and

. December. 16, 1980, and: February 11 and June 9, 1981. Enclosed is our '

final report. 3

j. ,If you have any questions concerning this matter, please get in touch with i D. L. Lambert at FTS 857-2581. i i -

! Very truly yours, TENNESSEE VALLEY AUTHORITY

-L.M. bills, Manager Nuclear Regulation and Safety h

[? Enclosure i

co: . Mr. Victor Stello, Jr., Director (Enclosure) l Office- of Inspection and Enforcement-

[ U.S. Nuclear. Regulatory Commission.

i ' Washington, DC 20555

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-i 8109090096 810831

'tPDR ADOCK 05000430 PDR .

.. An Equal Opportunity Employer F . , _

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ENCLOSURE FLLEFONTE NUCLEAR PLANT UNITS 1 AND 2 SOCKET K"LD MISALIGNMENT ON ESSENTIAL AIR SYSTEM WELDS NCR 1267 10 CFR 50.55(e)

FINAL REPORT Description of Deficiency Approximately 13 of 21- ocket welds in the Essential Air System piping f

surveyed by nondestructive examination (NDE) apparently failed to meet TVA welding specifications and procedures (G-29M, drawing 1.M.1.2-11 R1) relative to minimum pipe-to-socket fitting engagement requirements.

Further investige. tion revealed that 20 percent of approximately 100 socket welds in various other systems surveyed also failed to meet the same specifications.

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Safety Implications l The original concern was that the subject socket welds were installed a in such a manner as -to render them inadequate. However, failure to comply with minimum socket weld engagement as defined by G-29M will not degrade the weld (s). Therefore, this deficiency involves no safety' implications.

Corrective Action l TVA has reviewed the subject concern thoroughly and concludes that t'ae l requirements of G-29M are overly restrictive in regard to the i necessary engagement of socket welds. G-29M has been revised to l provide more reasonable requirements for socket weld engagement.

In its review, TVA consulted with analysts of the ASME working group on piping. These analysts advised TVA that as long as the piping is engaged sufficiently to allow the weld to be made, engagement is l adequate. This is because any additional engagement does not contribute to the strength of the joint.

! TVA radiographed over 300 socket welds to determine the scope of the problem. Forty-two (12) of the 200 welds were identified as not meeting the precise specifications of G-29M. Yet, all 42 met the

! approximate 1/16-inch minimum gap requirement of the ASME Code. In addition, each of the welds has at least 1/8-inch engagement which is

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l l- more than adequate to ensure a proper weld.

G-29M was revised to change the rigid and untenable requirements of L

the specification to guidelines. These guidelines will be used to aid craf ts in determination of proper engagement in keeping with ASME Code i

requirements. The revision of G-29M was completed on' August 14, 1981. Because it ;is no longer required, TVA will discontinue the

- routine spot radiography of socket joints which was initiated in March 1981 to determine the scope af this problem.