ML19261E266

From kanterella
Jump to navigation Jump to search
Forwards IE Bulletin 79-02,Revision 1, Pipe Support Base Plate Designs Using Concrete Expansion Anchor Bolts. Action Required
ML19261E266
Person / Time
Site: Wolf Creek Wolf Creek Nuclear Operating Corporation icon.png
Issue date: 06/21/1979
From: Seyfrit K
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
To: Koester G
KANSAS GAS & ELECTRIC CO.
References
NUDOCS 7907050487
Download: ML19261E266 (1)


Text

_

'Qlq;[

p&>n nic UNITED STATES o

[ yg.

I,j NUCLEAR REGULATORY COMMISSION

-s'.'QN;.,. (f REGION IV

)) g

j. y 9, fcg / g 611 RYAN PLAZA DHIVE, SUITE 1000

%, ' %./ ,p' AR LINGToN, TEX AS 76012 June 21, 1979 In Reply Refer To:

RIV Docket No.

STN 50-482/IE Bulletin No. 79-02 (Rl)

Kansas Cas & Electric Co.

Attn:

Mr. Glenn L. Koester Vice President-Operations Post of fice Box 208 Michita, Kansas 67201 Gentlenen:

Enclosed is IE Bulletin No. 79-02, Revision No. 1, which requires action by you with regard to your power reactor facility with an operating license or a construction permit.

Should you have any questions regarding this Bulletin or the actions required by you, please contact this office.

Sincerely,

_ m,,

O-1 4 / 0,,/ 'y, A darl

. S'e trk j

Director

Enclosures:

1.

IE Bulletin No. 79-02 Revision No. 1 2.

List of IE Bulletins Issued in Last Twelve Ponths cc: w/ enclosures Messrs. Nicholas A. Petrick, SNUPPS D. T. McPhee, Kansas City Power and Light Company Gerald Charnoff, Shaw, Pittnan, Potts & Trowbridge E. W. Creel, Kansas Gas and Electric Cocpany jf -

i,,'

79070504o,7

UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT WASHINGTON, D.C.

20555 IE Bulletin No. 79-02 (Revision No. 1)

Date: June 21, 1979 Page 1 of 6 PIPE SUPPORT BASE PLATE DESIGNS USING CONCRETE EXPANSION ANCHOR BOLTS Description of Circumstances:

Since the issuance of IE Bulletin 79-02 on March 8, 1979, IE inspection experience and many inquiries from licensees indicate that additional informa-tion and clarification is needed. This revision is intended to serve that purpose.

None of the requirements of the original Bulletin have been deleted, and the due date for completion of the requested actions (July 6, 1979) has not been changed. The following text supersedes the text of Bulletin 79-02.

Changes from the original text are identified by lines in the margin. The purpose of this revision is to identify acceptable ways of satisfying the Bulletin requirements.

While 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(c), filed by Long Island Li hting Company on Shorchsm Unit 1, indicate that design of base plates using b

rigid plate assumptions has resulted in underestimation 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 installations to be deficient.

Vendor Inspection Audits by NRC at Architect Engineering firms have shown a wide range of design practices and installation procedures which have been employed for the use of concrete expansion anchors. The current trends in the industry are toward more rigorous controls and verification of the instal-lation of the bolts.

The data available on dynamic testing of the concrete expansion anchors shew ratigue failures can occur at loads

--HMC;g4AJpp"_ chf*ic ca

"' ' " "p a -~ " " ' '

cities due to material imperfections also show low cycle dynamic failures DUPLICATE DOCUMENT due to joint slippage.

Entire document previously entered

  • Lines indicate changes to previous into system under:

%dhkdfjg8k ANO

{]

' - }

No. of pages:

//