1.This specification covers dimensions@ gaging practices@ and gages for internal threads in valves@ fittings (except couplings)@ and flanges for use with line pipe@ casing@ and tubing conforming to API specifications. NOTE: Coupling threw and external threads on wives and fittings are not covered by this specification. They should conform to the requirement specified in the corresponding pipe specification. 2. Nothing contained in this specification Is to be construed as granting any right@ by implication or otherwise@ for manufacture@ sale@ or use in connection with any method. Apparatus@ or product covered by letters-patent@ nor as Insuring anyone against liability for infringement of letters patent.
API STD 6-A-1957 history
1957API STD 6-A-1957 SPECIFICATION FOR THREADS IN VALVES@ FITTINGS@ AND FLANGES (Seventh Edition)
1956API STD 6-A-1956 SPECIFICATION FOR THREADS IN VALVES@ FITTINGS@ AND FLANGES (Tentative) (Sixth Edition)
1947API STD 6-A-1947 SPECIFICATION FOR THREADS IN VALVES@ FITTINGS AND FLANGES (Tentative) (Fifth Edition)