ML20155F090

Forwards Analysis Evaluating Continued Service for CR Drive Cap Screws That Are Currently Installed & Have Not Been Replaced as Part of Any Maint Activity

ML20155F090
Person / Time
Site:	Grand Gulf
Issue date:	10/29/1998
From:	Hughey W ENTERGY OPERATIONS, INC.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20155F094	List: ML20155F090 ML20155F196
References
GNRO-98-00084, GNRO-98-84, NUDOCS 9811050298
Download: ML20155F090 (2)

Text

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O Ent:rgy oporttions,Inc.

h PO. Box 756 Port Gbson, MS 39150 Tel 601437-6470 W.K.Hughey October 29, 1998- Usawy a av um Anars U.S. Nuclear Regulatory Commission Mail Station P1-37 Washington, D.C. 20555 Attention: Document Control Desk

Subject:

Grand Gulf Nuclear Station Unit 1 Docket No. 50-416 License No. NPF-29 Analytical Evaluation of CRD Cap Screws GNRO-98/00084 j Gentlemen:

4 ASME Section XI (the Code) requires that certain inspections be performed during each inspection Interval, including the inspection of the Control Rod Drive (CRD) mounting flange cap screws. Certain of the cap screws were rejected by visual examination when (

indications of degradation were discovered. Conditions found to be unacceptable by visual examination are required to be corrected either by repair or replacement or, alternatively, may be accepted by analytical evaluation conducted in accordance with article IWB-3600 of the Code. An evaluation was subsequently completed which determined that the discovered conditions were acceptable "AS-IS". Because the condition was found to be acceptable by the prescribed evaluation, the remaining cap screws were not required to be removed and inspected.

The enclosed analysis evaluates continued service for the CRD cap screws that are currently installed and have not been replaced as part of any maintenance activity, as then screws may be assumed to contain similar conditions to those discovered during the inspections. The analysis does not permit reinstallation of degraded cap screws because it does not consider the additional cycle of re-torquing and the consequent effect on flaw propagation. The Code requires that any conditions found to be acceptable by analytical

/[f evaluation be reported to the NRC in accordance with subparagraph IWB-3125(b). This evaluation is being provided to meet the reporting requirement of the Code and, A consequently, Entergy is not requesting review and approval of the analysis. If you have /) va any questions or comments concerning this report, please contact Bill Brice at 601-437-l 6556.

Yours truly, f O P .! 3 WKH/WBB/wbb l attachment j l- cc: - (S .3 Next Page)  !

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.. Ms.-J. L. Dixon-Herrity,' GGNS Senior Resident (w/a) -

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' Mr. L.'J. Smith (Wise Carter).(w/a) ,

, Mr. N. S. Reynolds (w/a)" '

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Mr. E. W. Merschoff (w/a) ,

, Regional Administrator!

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Mr.' J. N. Donohew, Project Manager (w/2) -

- Office of Nuclear Reactor Regulation

U.S. Nuclear Regulatory Commission Mail Stop 13H3 Washington, D.C. 20555 --  ;

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