DCL-85-074, Final Deficiency Rept Re Cracks in Welds on Pipe Rupture Restraints Made by Pullman Power Products.Unacceptable Welds Repaired or Modified

Final Deficiency Rept Re Cracks in Welds on Pipe Rupture Restraints Made by Pullman Power Products.Unacceptable Welds Repaired or Modified

ML20099H091
Person / Time
Site:	Diablo Canyon
Issue date:	02/22/1985
From:	Shiffer J PACIFIC GAS & ELECTRIC CO.
To:	Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
References
CON-#185-814 DCL-85-074, DCL-85-74, OL, NUDOCS 8503150170
Download: ML20099H091 (2)

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+ diCSVE9 PACIFIC GAS AND ELECTR,IC C O M PANY G5FE 25 FM R '>r bbMb l 77 BEALE STREET . SAN FRANCISCO, CALIFORNI A 94106 . (415) 781-4211 . TWX 910 372-6587 JAMES D. SHIFFER mu1TExx. February 22, 1985 PGandE Letter No.: DCL-85-074 Mr. John B. Martin, Regional Administrator U. S. Nuclear Regulatory Connission, Region V 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596-5368 Re: Docket No. 50-323 Diablo Canyon Unit 2 Final 50.55(e) Report - Rupture Restraints

Dear Mr. Martin:

PGandE letter dated May 3,1979 informed your office that cracks were discovered during visual inspections of full penetration welds on Unit 1 pipe rupture restraints. The welds were made by Pullman Power Products Company. A program was initiated to identify the type, cause, and extent of the situation. This program was outlined in a PGandE letter dated May 3,1979 and applied to Unit 1.

A final report for Unit 1 welds was submitted to the NRC on December 9,1980 That report established the cause of the cracking as inadequate or improper control of welding parameters. The Unit 1 program included inspection of all accessible full penetration welds greater than 1-1/2 inches on rupture restraints. In the pipeway area where the original cracking was discovered, all accessible full penetration welds were inspected. Peportable indications were identified. Unacceptable welds were repaired or modified. Defective welds were discovered on only six specific joint configurations. To prevent recurrence, improved welding procedures and inspection methods were developed.

Based on results of the Unit 1 program, an inspection and repair program was initiated for Unit 2. The Unit 2 program is now complete. All full penetration welds having one of the six joint configurations identified in the Unit 1 test program as having potentially defective welds were reinspected or evaluated. Welds were either accepted or repaired using inspection criteria based on the requirements of AWS D1.0-69 All repaired welds were inspected and accepted in accordance with current QC procedures.

Welds that were partially or completely inaccessible for inspection were evaluated by Project Engineering. These welds were accepted based on current design requirements and existing documentation from the original inspections.

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8503150170 850222 PDR ADOCK 05000323 S PDR

,Mr. J. B. Martin

. PGandE Letter No. DCL-85-074 February 22, 1985 Page 2 PGandE believes the actions taken have corrected all deficiencies that were reportable under 10 CFR Part 50.55(e).

Kindly acknowledge receipt of this materiel on the enclosed copy of this letter and return it in the enclosed addressed envelope.

Sincerely, cc: R. T. Dodds G. W. Knighton H. E. Schierling Service List l

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