49 CFR § 178.33-6
Manufacture
November 18, 2020
(a) By appliances and methods that will assure uniformity of completed containers; dirt and scale to be removed as necessary; no defect acceptable that is likely to weaken the finished container appreciably; reasonably smooth and uniform surface finish required.
(b) Seams when used must be as follows:
(1) Circumferential seams: By welding, swedging, brazing, soldering, or double seaming.
(2) Side seams: By welding, brazing, or soldering.
(c) Ends: The ends shall be of pressure design.
[29 FR 18823, Dec. 29, 1964, as amended by Order 71, 31 FR 9074, July 1, 1966. Redesignated at 32 FR 5606, Apr. 5, 1967]