ML19345C486

Significant Deficiency Repts SD 369/80-21 & SD 370/80-16 Re LOCA Pressure Effects Not Considered in Analysis of Piping W/Cold Penetrations Initially Reported 801031.Comprehensive Program Initiated to Correct Problems

ML19345C486
Person / Time
Site:	McGuire, Mcguire
Issue date:	11/26/1980
From:	Parker W DUKE POWER CO.
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
Shared Package
ML19345C484	List: ML19345C483 ML19345C485 ML19345C486
References
10CFR-050.55E, 10CFR-50.55E, SD-369-80-20, SD-370-80-16, NUDOCS 8012050314
Download: ML19345C486 (3)

Text

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.r. James P. O'Reilly, Director U. S. Nuclear Regulatory Camtission Pcgion II 101 burietta Street, Suite 3100 Atlanta, Georgia 30303 Pc : tkoaire Nuclear Station Units 1 and 2 Dccket tbs. 50-369 ard 50-370 D2ar Mr. O'Reilly:

Pursuant to 10CFR 50.55c, please find attached Significant Deficiency Pepert SD 369/80-21, 370/80-16.

Very tntly yours,

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bC' i :n Williaa O. Parker, Jr.

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j',/ ',7/f;g GAC:vr Attachrent cc: Director T. J. Donat Office of Inspection ard Enforcenent NIC Resident Inspector U. S. Nuclear Pc3ulatory Cornission ttGuire Nuclear Station Washington, D. C. 20555 l

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FCCUIRE NUCIPAR ST7aION UNITS 1 & 2 PEPORT NO: SD-369/W -21, 370/80-16 i)

REPORT DATE: November %- 1980 t INITIAL NorIFICATION DATE: October 31, 1930 FICILITY: McGuire Nuclear Station, Units 1 & 2 IDFi.'PIFICATION OF DEFICIDCY: IICA (Loss of Coolant Accident) Pressure Effects Not Considered in Analysis of Piping With Cold Penetrations DESCRIPTIG1 OF DEFICIECI:

1his report describes a deficiency in piping analysis of 1ines penetrating containment through bellows-type cold penetrations whereby Contaiment pressure due to IfCA was not considered. The design conficuration of the hellows-type cold penetration allcws for Containment movc5mnt without affecting the piping, ha..uver, internal Contaiment pressure acts on a flat bulkhead which rigidly connects the piping to the tellows. Because the bellows can expand, the pressure load is applio:1 to the piping with a resultant load on its support / restraint system. including an anchor point at the Reactor Building (concrete) wall.

scce piping systcms penetrate straight through bo'.h Containnent and the Pcactor Building while others are luuted through Containrent and the Reactor nuilding at different azinuths and elevations. In the fonner case, an evaluation of higher loads on penetration structures is required. In the latter case, evaluations of pipe stresses, support / "restraint locations and loads, and leads on penetration structures are required. anty-six (26) piping analysis math models recuire reanalysis. An estirrated eighty-two (82) support / restraints require revisica and sctre hardware changes.

IMALYSIS OF FAFETY IVPLICATIQ1:

iebrst case safety consequence is that piping which penetrates Contaiment through hellows-type cold penetrations is not qualified for the Faulted CoMition in-clMing pressure buildup inside of Containment due to IfCA. For a postulatM IICA, containment isolation cannot be assured assuming inadequate support / restraint designs.

CORRECTIVE ICTICti:

A concrehensive program has been initiatcd to conplete the following:

(1) Review all piping penetrations and identify the following:

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Ncue:ber 26, 1980 Page 2 (a) locations at which bellows-type cold penetrations are used and the pipe routing is straight through Contamment and the Reactor Building Concrete Wall.

(b) Iocations at which bellows-type cold pcnetrations ar!e'used

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and the piping penetrates the Containnent and Reactor Building l at different locations (azinuth and/or elevation) . l (c) T_ocations at which piping penetration assorblies otirr than bellows-type cold penetrations are utilized.

(2) Perform stress analysis of piping associated with Itan (Ib) above to include IOCA pressure effects on Centainnent penetration asse:rblies . Confirm adequacy of existing pipe stress analysis, support / restraint locations and loads, ard penetration asscrblies, or define necessary hardware chmges.

(3) Review structural calculaticas for penetration asserblies in Itens (la) and (le) and confirm that Contaiment isolation for the Faulted l Ccndition is assured, including IOCA pressure consideration.

(4) Make necessary hardeare changes to affected itans.

(5) Revice piping analysis procedures to confirm tlnt IDCA pressure

.loadiny is properly included in subscquent piping analyses as appropriate.

Schedules for comletion of the above corrective action itans are as follows:

Camletion Date Corrective Action Itan Linit 1 Unit 2 (1) Penetration Review / Identify Canplete 6/1/81 (2) Piping Analysis Ccnfirnution 12/19/80 Per Unit 2 Construction Schedul (3) Penetration Calc. Review 12/19/80 Per Unit 2 Construction Schedul (4) Hardware Changes 1/28/80 Per Unit 2 Construction Schedul (5) Procedure Confitnation -

3/1/81

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