Document: NRC Regulatory Guide
Document ID: c6e354c2-cc83-4d3d-b01b-b43865ccdac6
Document Type: regulatory_guide
Title: Control of Ferrite Content in Stainless Steel Weld Metal + HISTORY - HISTORY DG-1279 , Proposed Revision 4, published 09/2012 (Rev. 4)
Source: NRC Regulatory Guide Division 1
Source URL: https://www.nrc.gov/docs/ML1202/ML12024A004.pdf
Revision Date: 2023-06
Chapter: 
Section ID: RG-1.31
CFR Part: 
CFR Title: 

Content:
oduction usage, the delta ferrite content of test weld deposits from each lot and each heat of weld filler metal procured for the welding of austenitic stainless steel core support structures, reactor internals, and Class 1, 2, and 3 components should be verified for each process to be used in production. Delta ferrite determinations are not necessary for type 16-8-2 filler metal in filler metal specifications SFA-5.4, “Specification for Stainless Steel Electrodes for Shielded Metal Arc Welding,” and SFA-5.9, “Bare Stainless Steel Welding Electrodes and Rods” of Section II of the ASME Code, or for filler metal used for weld metal cladding. Delta ferrite determinations for consumable inserts, electrodes, rod, or wire filler metal used with the gas tungsten arc welding process, and deposits made with the plasma arc welding process, may be predicted from their chemical composition by using an applicable constitutional diagram in the applicable filler metal specification (e.g., WRC-1992 diagram for stainless steel weld metal in SFA-5.9 of Section II of the ASME Code). For all other processes, delta ferrite verification should be performed through tests using magnetic measuring devices on undiluted weld deposits. For submerged arc welding processes, the verification tests for each wire and flux combination may be made on a production weld or simulated production weld. All other delta ferrite weld filler verification tests should be made on weld pads that contain undiluted layers of weld metal. 2. Ferrite Measurement The NRC staff considers the procedures for pad preparation and ferrite measurement in American Welding Society (AWS) A5.4/A5.4M, “Specification for Stainless Steel Electrodes for Shielded Metal Arc Welding,” (Ref. 5) and SFA-5.4 of Section II of the ASME Code acceptable. 3. Instrumentation The weld pad should be examined for ferrite content by using a magnetic measuring instrument that has been calibrated against a Magnegage in accordance with AWS