a. This standard covers ductile iron plug valves with flanged ends in nominal sizes of 1 inch through 24 inches corresponding to the nominal pipe sizes (NPS) in ANSI* B36.10. b. This standard covers valves having nominal pressure ratings of 150 pounds and 300 pounds as specified in ANSI B16.5 for service temperatures from -20 F to 650 F. c. These valves are of the lubricated or non-lubricated type having two-way coaxial ports. d. Valves covered by this standard shall conform to the requirements of API Standard 599@ except as modified herein@ for flanged valves of corresponding sizes and nominal pressure ratings. The standard nomenclature for valve parts is listed within Fig. 1 of API Standard 599. * American National Standards Institute@ Inc.@ 1430 Broadway@ New York@ N.Y. 10018.