ML19256B236

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Responds to Re Design Deficiencies in Support Base Plates.Nrc Still Waiting for S&W Evaluation of Both Piping & Electrical Type Supports.Info Will Be Evaluated as Part of Continuing Safety Review
ML19256B236
Person / Time
Site: 05000516, 05000517, Shoreham  File:Long Island Lighting Company icon.png
Issue date: 01/15/1979
From: Bordenick B
NRC OFFICE OF THE EXECUTIVE LEGAL DIRECTOR (OELD)
To: Like I
REILLY & LIKE
Shared Package
ML19256B235 List:
References
NUDOCS 7906020226
Download: ML19256B236 (1)


Text

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ry 15, 1979 v,.

Irving Like, Esq.

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Reilly, like and Schneider 200 Ucst Main Street Babylon, Ucw York 11702 In the Matter of L0flG ISLAilD LIGHTING COMPAf1Y (Jamesport fluclear Power Station, Units 1 & 2)

Docket tios. 50-516 & 50-517 and in the Matter of LONG ISLAND LIGHTING COMPANY (Shorcham fluclear Power Station, Unit 1)

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Docket tio. 50-322

Dear Mr. Like:

This is in further response to your letter to me dated December 5,1978, "regarding design deficiencies in the support base plates for both Shoreham and Jamesport".

I have been advised as follows regarding. -

the matter in question:

1.

The Staff (flRR) is still awaiting the Stone and Webster evaluation of both piping and electrical type supports and will review it as part of its continuing safety review of both Shoreham and Jamesport.

2.

I&E still has the Stone and Webster "Part 21 deviation" aspect of the matter under review.

In any event, the technical problem is being handled by them on a generic basis.

I&E presently expects to issue a bulletin to all licensees and their contractors en January 26, 1979.

I will forward you a copy when it is available to me. -- ---- -

Sincerely, LWo h a Vk h.

Bernard M. Bordenick Counsel for flRC Staff 2268 286 1

2 90 6 02 0;L3-42

k1 UNITED STATES fiUCLEAR REGULATORY CCMISSION OFFICE OF INSPECTION AND EtiFORCEMENT WASHINGTON, D.C.

20555 March 8, 1979 IE Bulletin No. 79-02 PIPE SUPPORT BASE PLATE DESIGNS USING CONCRETE EXPANSION ANCHOR BOLTS Description of Circumstances:

Nhile performing inservice inspections during a March-April 1978 refueling outage at Millstone Unit 1, structural failures of piping supports for safety equipment were observed by the licensee. Subsequent licensee inspections of undamaged supports showed a large percentage of the concrete anchor bolts were not tightened properly.

Deficiency reports, in accordance with 10 CFR 50.55(e), filed by Long Island Lighting Ccmpany on Shoreham Unit 1, indicate that design of base plates using rigid plate assumptions has resulted in underestima-tion of loads on some anchor bolts.

Initial investigation indicated that nearly fifty percent of the base plates could not be assumed to behave as rigid plates.

In addition, licensee inspection of anchor bolt installations at Shoreham has shown over fifty percent of the bolt g

installations to be deficient.

Vendor Inspection Audits by NRC at Architect Fngineering firms have shown a wide range of design practices and installation procedures which have been employed for the use of concrete expansion anchces.

The current trends in the industry are toward more rigorous controls and verification of the installation of the bolts.

The data available on dynamic testing of the concrete expansion anchors show fatigue failures can occur at loads substantially below the bolt static capacities due to material imperfections or notch type stress risers. The data also show low cycle dynamic failures at loads below the bolt static capacities due to joint slippage.

Action to be Taken by Licensees and Pennit Holders:

For pipe support base plates that use concrete expansion anchor bolts in Seismic Category I systems as defined by Regulatory Guide 1.29, " Seismic Design Classification" Revision 1, dated August 1973 or as defined in the applicable FSAR.

1.

Verify that pipe support in the calculation of an analysis justifying the.

DUPLICATE DOCUMENT h

Entire document previously entered into system under:

ANO JT C 3l Q Cr0 2 2 No. of pages:

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