U.S. Code of Federal Regulations
Regulations most recently checked for updates: Feb 21, 2020
(a) All joints shall be fusion-welded in compliance with the requirements of AAR Specifications for Tank Cars, appendix W (IBR, see § 171.7 of this subchapter). Welding procedures, welders and fabricators shall be approved.
(b) Welding is not permitted on or to ductile iron or malleable iron fittings.