ML20216F329

Accepts 980406 Licensee Request for Approval to Install machine-welded SG Tube Plugs in Accordance W/Provisions of Paragraph IWB-4230, Tube or Tubesheet Hole Plugging by Fusion Welding, of Section XI

ML20216F329
Person / Time
Site:	Davis Besse
Issue date:	04/13/1998
From:	Modes M NRC (Affiliation Not Assigned)
To:	Hansen A NRC (Affiliation Not Assigned)
Shared Package
ML20216F306	List: ML20216F301 ML20216F329
References
NUDOCS 9804170033
Download: ML20216F329 (1)

Text

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NUCLEAR REGULATORY COMMISSION WASHINGTON. D.C. SpeeH001

\...../ April 13, 1998 MEMORANDUM TO: Allen G. Hansen, Project Manager Project Directorate ill 3 Division of Reactor Projects ill and IV FROM: Michael C. Modes, Acting Se6 on hhf Materials and Chemical Enginee

' Division of Engineering

SUBJECT:

REQUEST FOR APPROVAL TO INSTALL MACHINE-WELDED STEAM GENERATOR TUBE PLUGS By letter dated April 6,1998, the licensee for Davis Besse Nuclear Power Station (DBNPS) requested approval to install machine-welded steam generator tube plugs in accordance with the provisions of Paragraph IWB-4230, " Tube or Tubesheet Hole Plugging by Fusion Welding," of Section XI, " Rules for inspection of Nuclear Power Plant Components," of the American Society of Mechanical Engineers (ASME) Boiler and Pressure Vessel Code,1989 Edition. The licensee's request was necessary because it is currently committed to the 1986 Edition of ASME Section XI, and the provisions applicable to DBNPS for installing machine-welded plugs were included prior to the 1989 Edition of the ASME Code in Code Case N-389, " Alternative Rules for Repairs, Replacements, or Modifications,Section XI,-

Division 1." Per NRC Regulatory Guide 1.147, Revision 11, the NRC considers the installation of m6 chine-welded pn;gs to be an acceptable repair methodology provided the applicant submits for approval the appropriate edition and addenda of the ASME Code that is to be used for the repair before the start of the work. The licensee intends to use the provisions of IWB-4230 in the Eleventh Refueling Outagle (11RFO) commencing on April 11,1998, subject to NRC epproval.

The Materials and Chemical Engineering Branch has concluded that the licensee may utilize the provisions of Paragraph IWB-4230 of Section XI of the ASME Code (1989 Edition) for the installation of machine-welded steam generator tube plugs in 11RFO at DBNPS provided all related requirements of the respective edition of the code are met. The installation of these plugs per IWB-4230 should result in lower worker dose during the plugging process relative to manua!!y installing welded plugs.

r Docket No.: 50 346 i

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Enclosure l l

Contact:

P. Rush, DE/EMCB 415-2790 9804170033 980414 I PDR ADOCK 05000346 5 P PM [