ML20084N454

Final Deficiency Rept 83-04 Re Structural Steel Connection Rework Design Inadequacy.Initially Reported on 830429.Jam Nuts to Be Installed on Sliding Connections by 830801 & 840101 for Byron & 830725 & 1125 for Braidwood

ML20084N454
Person / Time
Site:	Byron, Braidwood, 05000000
Issue date:	05/26/1983
From:	Swartz E COMMONWEALTH EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
10CFR-050.55E, 10CFR-50.55E, 6653N, 83-04, 83-4, NUDOCS 8306030229
Download: ML20084N454 (2)

Text

A. ..

.1 . c Commonwealth Edison

) Ona First NationTl Pl;zt, Ch;Crgo, liknois

[ ~

\ l Address Reply to: Post Office Box 767

'y j Chicago, Illinois 6;690 May 26, 1983 Mr. James G. Keppler, Regional Administrator Directorate of Inspection and Enforcement - Region III U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, IL 60137

Subject:

Byron Station Units 1 and 2 Braidwood Station Units 1 and 2 30 Day Report to 10 CFR 50.55(e)

NRC Docket Nos. 50-454, 50-455, 50-456, and 50-457

Dear Mr. Keppler:

On April 29, 1983, the Commonwealth Edison Company Project Engineering Department notified Mr. Julian M. Hinds of your office of a deficiency reportable pursuant to 10 CFR 50.55(e) regarding structural steel connection rework at our Byron and Braidwood Stations. For your tracking purposes, this deficiency was assigned Number 83-04 for both stations.

c This letter fulfills the thirty (30) day reporting requirements of 10 CFR 50.55(e) regarding this matter and is considered to be a final report.

Description of Deficiency Original design requirements failed to provide adequate guidance to ensure a uniform and acceptable method to burr the bolt threads, thus necessitating the addition of a jam nut for slotted structural steel connections. Extensive rework is required to correct this deficiency.

Analysis of Safety Implication Installation requirements on the American Bridge Division Erection Drawings stated the burring of bolt threads. The requirement to burr the bolt thread was to ensure that the nut would not loosen overtime.

Commonwealth Edison Company authorized the revision for the instal-lation of jam nuts for all sliding connections as an added precaution to prevent the occurrence of the first nut becoming loose and disengaging from the connection.

B306030229 830526 b}9 PDR ADOCK 05000454 MAY 27 FEsl

,2, +A

^}

J. G. Keppler :May 26, 1983 Corrective Action Jam nuts are being installed on structural steel connections in the Containment Buildings where a sliding-connection is provided. This includes structural steel used as floor-framing and miscellaneous steel used for component supports. The requirements for installing jam nuts are specified on the following design drawings:

S-1097 - Revision'U, dated October 15, 1982.

S-960 - Revision N, dated March 18, 1983.-

ENC-3270 - Dated, January 4, 1983.

The design drawing requirement to provide jam nuts on structural steel will be implemented at Byron and Braidwood Stations in the same manner as any other Sargent & Lundy drawing revision. The installation contractors' approved Q.A./Q.C. procedure will ensure proper installation.

Byron Station is expected to complete jam nut installation for Unit 1 containment on August 1, 1983, and Unit 2 containment on January 1, 1984.

Braidwood Station 1s expected to complete jam _ nut installation for Unit 1 containment on~ July 25, 1983, and Unit 2 containment on November 25, 1983.

Please address any questions that you or your staff may have concerning this matter to this office.

Very truly yours, E. Douglas Swartz Nuclear Licensing Administrator 1m

=cc: Region III Inspector - Byron Region III Inspector - Braidwood Director of Insp. and Enf.

US Nuclear Regulatory Commission Washington, D.C. 20555 6653N

. - - - . . _ . -