Document: NRC Regulatory Guide
Document ID: e9f2f7f8-8345-4591-a596-70b7ac0be7cf
Document Type: regulatory_guide
Title: Control of Electroslag Weld Properties + HISTORY - HISTORY DG-1223 , Proposed Revision 1, published 06/2009 (Rev. 1)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML0907/ML090750626.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.34
CFR Part: 
CFR Title: 

Content:
test for ensuring the soundness of the center weld metal would be to perform an impact test with the specimen notch located at the weld center as shown in Figure A. Section III requires that material having its mechanical properties enhanced by a heat treatment must subsequently be tested to ensure the effectiveness of the heat treatment. To provide this assurance for low-alloy steel electroslag production welds, the mechanical properties of the weld metal should be determined from the weld prolongation by tests similar to those required for the quenched and tempered base metal. For Class 2 vessels, it would not be necessary to test all electroslag weld seams, but at least one weld should be tested for each shell course. Industry experience with electroslag welded stainless steel components has shown that cracking in the weld solidification region is not a problem when the process is properly qualified and controlled. In addition, the weld metal structure and mechanical properties are generally acceptable. To ensure that the production welds are satisfactory, the welding process variables specified in the procedure qualification should be monitored during the welding process. C. REGULATORY POSITION Electroslag weld fabrication for core support structures and Class 1 and 2 vessels and components should comply with Section III and Section IX of the ASME Boiler and Pressure Vessel Code, supplemented by the following: 1. The procedure qualification for low-alloy steel and stainless steel welding should require the following: a. Process variables such as slag pool depth, electrode feed rate and oscillation, current, voltage, and slag conductivity should be selected to produce a solidification pattern (dendritic grain pattern) with a joining angle of less than 90 degrees in the weld center. b. A macro-etch test should be performed in the longitudinal weld direction of the center plane across the weld from base metal to base metal as shown in Figure A of this guide. The