ML20096F362

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Final Supplemental Potential Deficiency Rept PRD-81/29 Re Incorrectly Welded Temp Flex Co Spokes on Bellows End Sleeves of Penetration Assemblies.Initially Reported on 810529.All Corrective Actions & Insps Complete
ML20096F362
Person / Time
Site: Grand Gulf Entergy icon.png
Issue date: 08/15/1984
From: Richard J
MISSISSIPPI POWER & LIGHT CO.
To: James O'Reilly
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
AECM-84-2-0015, AECM-84-2-15, NUDOCS 8409070418
Download: ML20096F362 (3)


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MISSISSIPPI POWER & LIGHT COMPANY Helping Build Mississippi P. O. B O X 16 40, J AC K S O N, MIS SIS SIP PI 3 9 2 0 5

.ygg20P3  ?. 2 N.%.."'ff,".i..um.oem. August 15, 1984 U. S. Nuclear Regulatory Ccamission Region II 101 Marietta Street, N.W.

Suite 2900 i Atlanta, Georgia 30323 Attention: Mr. J. P. O'Reilly, Regional Administrator

Dear Mr. O' Reilly:

SUBJECT:

Grand Gulf Nuclear Station Unit 2 Docket No. 50-417 License No. NPF-13 File 0260/15525/15526 PRD-81/29, Final Supplemental Report, Unit "I Temp Flex Penetration Bellows Assemblies AECM-84/2-0015

Reference:

(1) AECM-81/226,6/25/81 (2) AECM-81/385, 10/6/81 (3) AECM-83/2-0003, 3/31/83 (4) AECH-83/2-0006, 10/7/83 On May 29, 1981, Mississippi Power & Light Company notified Mr. V. Brownlee, of your of fice, of a Potentially Reportable Deficiency (PRD) at the Grand Gulf Nuclear Station (GGNS) construction site. The deficiency concerned incorrectly welded spokes on the bellows end sleeves of penetration assemblies manufactured by the Temp Flex Company of Compton, California.

This deficiency was determined by MP&L to be not reportable and was closed out for Unit 1 and Unit 2 in Inspection Report 50-416/81-50 and 50-417/81-22. However, on March 1,1983, MP&L informed Mr. R. Butcher, of your office, that the PRD was being re-opened for Unit 2 to assure that the deficiency is adequately addressed.

Based on the results of our investigation, MP&L had determined that this deficiency was reportable under the provisions of 10CFR50.55(e) for Unie. 2 and notified the NRC in Reference 4. The deficiency is not reportable under 2 0CFR21 for Unit 2 since the af fected systems have not been turned over to MP&L.

All inspections and corrective actions have nu i been completed for Unit 2.

Details are included in our attached Final Report.

"* I' 8409070418 e40815 gDRADDCK 05000417 PDR fQ3 J. B. Richard " OFFICIAL COPY KDS:dr o ATTACHMENT .

p cc: See page 2 Member Middle South Utilities System

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Mr. J. P.,O'Reilly AECM-84/2-0015 NRC Page 2 cc: 'Mr. J. B. Richard Mr. R. B. McGehee Mr. Nicholas S. - Reynolds, Esq.

. Bishop, Liberman, Cook, Purcell & Reynolds 1200 Seventeenth Street, N. W.

Suite 700 Washington, D. C. 20036 Mr. Richard C. DeYoung, Director

-Of fice of Inspection & Enforcement U. S. Nuclear Regulatory Commission Washington, D.C. 20555 Mr. G. B. Taylor South Miss. Electric Power Association P. O. Box 1589 Hattiesburg, MS 39401 l

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1 Attachment to AECM-84/2-0015

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. FINAL SUPPLEMENTAL REPORT TO PRD-81/29 I. -Description of the Deficlency Penetration bellows assemblies manufactured by Tesip Flex have exhibited cracked and broken velds at the junction between the shroud support spokes and the bellows end sleeves. Contrary to Temp Flex design drauing .)

requirements, fillet welds were used by the supplier instead of full penetration welds.

This deficiency affects the Nuclear Boiler System (B21), Residual Heat Removal System (E12), Reactor Core Isolation Cooling System (E51), Reactor Water Cleanup System (G33) and the Fuel Pool Cooling and Cleanup System (G41). The five bellows assemblies contained in the Standby Liquid Control System (C41) do not have spokes; therefore, System C41 is not affected as was previously reported.

This deficienc'y is applicable to Unit 2 only, and does not apply to the NSSS supplier.

II. Analysis of Safety Implications Subsequent Temp Flex calculations state that a 1/8" fillet weld, in lieu of a full penetration weld, will support the shroud duriag a design seismic event. Inspection results of the "as welded" condition indicate that certain spokes have undersis.ed welds, i.e., less than 1/8". Failure of the welds to support the shroud could cause a puncture in the bellows convolution and breach.the drywell pressure boundary.

Therefore, had the cited condition remained uncorrected, the deficiency could i have af fected adversely the safety of operations of the nuclear power plant

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! at any time throughout the expected lifetime of the plant.

Our Constructor has determined that the deficiency could apply to nineteen (19) of the twenty-four (24) be11cvs assemblies supplied. Five (5) bellows assemblies in System C41 (Standby Liquid control System) do not have spokes.

l The inspection of all nineteen (19) bellows assemblies has been completed and all of the nonconformances noted have been ideatified, dispositioned, repair welded as necessary, and accepted on Nonconformance Report (NCR) 6535.

III. Corrective Actions The cause of the deficiency was .that the personnel performing the installation and inspeution of the welds did not review the actual drawing requirements for weld preparation.

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F Attachment to AECM-84/2-0015 Page 2 of 2 The extent is limited to nineteen (19) bellows supplied by our Architect / Engineer.

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S!.nce all the bellows supplied by Temp-Flex under Specification M318.0 have been delivered for Unit 2, no additional quality requirements can be imposed on the vendor at this time. Of the nineteen bellows in question, eleven (11) have since been installed and inspected with no additional damage incurred.

As the remaining eight bellows are installed they will be monitored closely to assure proper handling and final inspections will be performed.

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