- (a) Postweld heat treatment of the inner container is not a specification requirement.
- (b) Postweld heat treatment of the cylindrical portions of the outer shell to which the anchorage or draft sills are attached must comply with AAR Specifications for Tank Cars, appendix W (IBR, see § 171.7 of this subchapter).
- (c) When cold formed heads are used on the outer shell they must be heat treated before welding to shell if postweld heat treatment is not practicable due to assembly procedures.
[Amdt. 179-9, 36 FR 21341, Nov. 6, 1971, as amended at 68 FR 75762, Dec. 31, 2003]