This document summarizes information on the welding of titanium pipe.1 The information has been collected from the welding literature and from various company shops and laboratories. The document is intended to serve as a welding guide. This standard makes use of both U.S. Customary Units and the International System of Units (SI). The measurements may not be exact equivalents; therefore@ each system must be used independently of the other without combining in any way. The standard with the designation D10.6:2000 uses U.S. Customary Units. The standard designation D10.6M:2000 uses SI units. The latter are shown within parenthesis ( ) or in appropriate columns in tables and figures.1 Where pipe is used in this document@ it refers to both piping and tubing.