This document provides dimensional standards for butt welding pipe fittings according to ANSI B-16.9, B-16.28, and MS SS P43 standards. It includes specifications for 90 degree elbows and 180 degree return bends in short radius configurations for various nominal pipe sizes from 1/2 inch to 36 inches. Charts list dimensions for outside diameter, center to face, back to face, center to center, and other measurements required to construct the pipe fittings.