1.1 This specification covers only factory-made wrought aluminum and aluminum-alloy welding fittings in contrast to field-made fittings. The term "welding fittings" applies to butt-welding or socket-end parts, such as 45° elbows, 180° return bends, 90° short radius elbows, and other types made to the dimensional standards specified by ANSI B16.9, B16.11, and B16.28. Note 1-Throughout this specification use of the term alloy in the general sense includes aluminum as well as aluminum-alloy. 1.2 For acceptance criteria for inclusion of new aluminum and aluminum alloys in this specification, see Annex A1. 1.3 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only.