This standard is intended to cover API ringjoint dimensions for American Standard (ASA)1 steel flanges@ (threaded with API standard line pipe threads2 or American Standard thread)@ other sizes of flanges as required@ and rolled@ and slip-on welding and welding neck flanges. These ring-joint dimensions are also to be used on steel flanged valves and fittings where connected to ring-joint flanges@ or where ring joints are required in piping connections. This standard also covers ring-joint flange unions for use with API tubular goods*@ (line pipe@ casing@ drill pipe@ and tubing). 1ASA Stondards mentioned herein may be Bocurcd from the Amorinan Standards Association@ 29 West 89th St-@ New York@ N. Y. 2See API Stds. No. 5-F: Threads in Fittingi.
API STD 5-G-3-1940 history
1945API STD 5-G-3-1945 STANDARD ON RING JOINTS FOR STEEL FLANGES AND FLANGE UNIONS (Third Edition; Incorporates Supplement 1: August 1946)
1940API STD 5-G-3-1940 RING JOINTS FOR STEEL FLANGES AND FLANGE UNIONS (Second Edition; Incorporating Supplement: January 1941)
1937API STD 5-G-3-1937 RING JOINTS for STEEL FLANGES AND FLANGE UNIONS (FIRST EDITION)