ML20101N844

Interim Part 21 Rept Re Potential Safety Concern on Matl for Fabrication of Permanent Canal Seal Plate.Licensee Will Provide Final Rept to NRC in Approx Six Months Upon Completion of Evaluation of Welds

ML20101N844
Person / Time
Site:	Arkansas Nuclear, Crystal River
Issue date:	04/05/1996
From:	Taylor J FRAMATOME
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
REF-PT21-96 NUDOCS 9604090154
Download: ML20101N844 (2)

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l IIm F R AM ATO M E TECHNOLOGlES Integrated Nuclear Services April 5,1996 JHT/96-30 Document Control Desk U. S. Nuclear Regulatory Commission Washington, DC 20555-0001

Subject:

Interim Report of Potential Safety Concern on Material Used for Fabrication of Permanent Canal Seal Plate Gentlemen:

The purpose of this letter is to provide you with preliminary information on a Potential Safety Concern. The concern relates to the use of material constructed with welded angles that are not allowed by ASME A479, for a safety related component, the permanent canal seal plate.

Use of the welded angles is thought to not adversely affect safety during normal power operation.

Reliance on the welded angles may be of concern when the permanent canal seal plate fulfills its function of retaining water in the reactor canal during refueling activities. This latter concern is the basis for the Preliminary Safety Concern. In addition, our preliminary evaluation indicates that the highest load on the weld would occur during a core flood line rupture; the concern here being that the structure might become a missile.

The subcontractor for fabrication of the seal plates, currently in use at Arkansas Nuclear One and Crystal River-3, purchased commercial grade materials with Certified Materials Test Reports (CMTR's). FTI (then BWNT) upgraded this material to " safety related" and certitied as such based on laboratory tests and alloy analyses on sample pieces from each angle. Examination of recently purchased identical material revealed the presence of welds, which is not allowed by ASME A479. Documentation received from the material vendor, upon questioning by Framatome Technologies, verified that the material used for the permanent canal seal plates currently in use was also welded. There are no questions about other materials used in the fabrication of the seal plates.

The seal plates currently in use have been cycled through normal operation and a refueling. The

plates have been visually inspected and show no signs of degradation. The two affected plants have been notified of the need to revise the material certification and of the need to augment i visual inspection prior to each canal flooding.

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9604090154 960405 -

PDR ADOCK 05000302 S PDR l g 3315 Old Forest Road, P.O. Box 10935, Lynchburg, VA 24506-0935 Telephone: 804-832-3000 Fax: 804-832-3663

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FTI has not completed its evaluation of the welds. This letter is not a notification of a substantial safety hazard under 10CFR21.

! FTI will provide a final report to the NRC in approximately six months upon completion of the evaluation of the welds and final resolution of the Preliminary Safety Concern.

If you have any questions concerning this matter, please contact the undersigned at l 804-832-2817 or Robert Schomaker at 804-832-2917.

Very truly yours,

. >l . d&w J. H. Taylor, Manager i Licensing Services JHT/bcc l c: B. W. Sheron/NRC I

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