ML19331C334

Part 21 Rept Re Inaccurate Natural Frequency Repts Submitted by Valve Suppliers to Original Purchase Spec Requirements. Caused by Apparent Computer Programming error.Re-evaluation or Mod of Valves in Process

ML19331C334
Person / Time
Site:	Grand Gulf
Issue date:	08/01/1980
From:	Mcgaughy J MISSISSIPPI POWER & LIGHT CO.
To:
References
REF-PT21-79-168-003 AECM-80-160, NUDOCS 8008140570
Download: ML19331C334 (2)

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I MISSISSIPPI POWER & LIGHT COMPANY

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Helping Build Mississippi L'- ' P. O. B O X 16 4 0, J A C K S O N, MISSISSIPPI 39205 NUCLEAR PRODUCTICN DEPARTMENT August 1, 1980 Office of Inspection & Enforcement U. S. Nuclear Regulatory Commission Region II

%- / f. f- 0 0 3 101 Marietta Street, N.W.

Suite 3100 Atlanta, Georgia 30303 Attention: Mr. J. P. O'Reilly, Director

SUBJECT:

Grand Gulf Nuclear Station Units 1 and 2 Docket Ncs. 50-416/417 File 0260/15525/15526 PRD-79/13, Final Report, William Powell Valves, Seismic Evaluation AECM-80/160 J

References:

1) AECM-79/ll2, 10/4/79

2) AECM-79/141, 12/18/79 THIS DOCUMEllT C0tlTAINS 3)AECM-80/68,4/4/89 POOR QUAUTY PAGES On September 4, 1979, Mississippi Power & Light Ccapany notified Mr. V. L. Brownlee of ycur office of a Potentially Reportable Defi-ciency (PRD) at the Grand Gulf Nuclear Station (GGNS) construction site. The deficiency concerns William Powell supplied valves which cay not meet the seisnic requirements of the original purchase order.

l l We have determined this deficiency to be reportable within the meaning of both 10CFF.50.55(e) and 10CFR21. Details are described in the attached final report.

Yours truly, fh l gg

/

J. P. McGaughy, Jr.

Assistant Vice President, Nuclear Production ATR:mt Attachment ec: Mr. N. L .Stampley Mr. Victer Stelle, Directh Mr. R. 3. McGehee Division of Inspection & Enforcement Mr. T. 3. Conne r U. S. Nuclear Regulatory Commission Washingten, D.C. 20555 t 8008140678 $ Memeer Midcle Seuth utilities System

Attachment A to AECM-80/160

, , . Page 1 of 1 FINAL REPORT FOR PRD-79/13 I. Description of Deficiency During the requalification of valves to the new loads requirements, the natural frequency reports submitted by valve suppliers to the original _ purchase specification requirements were reviewed by our Architect / Engineer. As a result, the accuracy of the reports sub-mitted.by. William Powell Valves was questioned and an independent laboratory was engaged to perform a finite element analysis on three of the valves. The results of this analysis differed from the results submitted by William'Powell by 200 to 2000%. The natural frequency of some valves is, therefore, below the minimum natural frequency required by design specificatien.

II. Analysis of Safety Implications During a postulated seismic event, valve function cannot be assured due to low natural frequency. This condition could have resulted in an overstress condition at the pipe connection or hinder valve operation had it remained uncorrected.

III. Corrective Actions Taken The incorrect natural frequencies were caused by an apparent computer programming error by the sub-supplier who performed the analysis for the William 'Powell Company. The extent of the problem has been identified, by the William Powell Company, as affecting.only Grand Gulf. It is contemplated for those valves with a resonant frequency below 33 Hertz to raise their resonant frequency to acceptable levels. This action is in process at this time through either re-evaluation or modification to the valves themselves.

The William Powell Ccapany has notified the NRC of the applicability of 10CFR21 by submission of the attached written report.

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tr!E WM. PO? ELL CvMPANY yj, . Ec:t spcng or,we w,ue, p.o. Bex 40:x. Coce.a 4F '

OMJ $111552 ~xo -

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N::vecier 12, 1979 -

-fJnited States Nucicar Regulatcry Cer=lesico thsten J V 611 Ryan Plaza Drive Seite !CCO A.linston, Teu.s 76012 Attenilem Mr. K.V. Seyfrit, Director

Reference:

Ph:ne converse:Jen ci 11/9/79 between Mr. Edwin E. t'tinterfele.

and Mr. Joe Lef:us of Powell cod Mr. Ramon Hall, Outy Officer, !<

Doce Mr. Seyfrit: ,

The folicwing is a confirmation of a verbal report in cccordance with NRC Fesu-

!ctica 10CFR Part 21 ci a noncemofiance to specifiestices for nuclear valves supplied by the tYm. Powell Company to the Mississippi Power and Licht Co. .

Cc.d Gulf f4.ctccr Statico, Units 1 and 2, Pert Gibscn, Mississippi 39150. Th" .

e,:ctesr picnt 1: still utder constructica end therefore, is not in operaticn. The tyr.c4lanca wa3 vcritied to cf.Izt by the tYm Pcucti Cormany on Noaember C, ~~

1979.

% he.ve supplied ML~issippi Pewcc ced Ligh: eilth C! css 1, 2, cad 3 valves wd.ic.

wers, by design specifiestion, to have a minimten natural frecuency of 33 herts.

,. In tbs process of reviewing ths s>ossibill:y of rccertifying these vcives to have c

In7nuten natural (remency ct 100 her::, in ccccedence wl:S a Sechtel pec::csed cpecification change, it nes ciscovered that tSo celginal calculaticos were in l ceror. iie han determined th:t the errce lies in a ccercutcc progrzm which wc:

chveicped by ene of c,uc subccrire.c:ces.

% find that this errcr la nct OI a fixed m 5nitude, VCr DOC % It dIST33IIIY DII VEIY*

e::ptied. The.crece magnitu& is dependent icon the geometry of each valve sr.-d cf.cre!cre, necessitates e reanalysis cf esch cualifying seismic recer: for this customee. The valves, we knen today, tha: fall belew the coccifics:Icn recdec-

. recta are cy!leder coars:ed S anc r ~ ~ ' " - ' '~

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e:rcesh F, ! A.21 A thecugn 0, d : DUPLICATE DOCUMENT speciticction S645 u 242.0. H

[' j Entire document previously t entered into system under l

l0 bd 79I2.169$54f no 1N0l$W6gY:

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