This standard applies to flanged and flangeless rotary control valves using a full ball or a segment of a ball and other rotary-stem control valves@ sizes (20 mm) 3/4 inch through (600 mm) 24 inches for Classes 150 through 600. This standard is not intended to include butterfly valves. Purpose The purpose of this standard is to aid users in their piping designs for flanged and flangeless control valves by providing valve face-to-face dimensions without giving special consideration to the equipment manufacturer to be used.