This document specifies the requirements for the manufacture and quality assurance of friction weldments. It also contains requirements for the qualification of welding machines@ welding procedures@ and welding operators. This specification is directly applicable to inertia@ direct-drive@ and friction stir variants of friction welding@ but may also be used with orbital@ angular reciprocating@ and linear reciprocating variants. This standard makes use of both the U.S. Customary Units and the International System of Units (SI). The latter is shown within brackets or in appropriate columns in tables and figures. The measurements may not be exact equivalents; therefore@ each system shall be used independently. Safety and health issues and concerns are beyond the scope of this standard@ and therefore not fully addressed herein. Safety and health information is available from other sources@ including@ but not limited to@ ANSI Z49.1@ Safety in Welding@ Cutting@ and Allied Processes1 and applicable federal and state regulations. 1 ANSI Z49.1 is published by the American Welding Society@ 550 N.W. LeJeune Road@ Miami@ FL 33126.