scope:

This standard covers the preparation of buttwelding ends of pipe, valves, welding neck flanges, and pipe fittings, but is equally applicable to other piping components which are connected into the piping system by buttwelding.

It includes requirements for re-entrant shapes for heavy wall ends, welding bevel profiles, inside contours for joints made with or without backing rings, and machining dimensions with their tolerances. The preparation for back· ing ring, if any, must be specified in ordering material to this standard.

This standard does not take into consideration the welding process or procedure used.

Materials of piping components for which these welding ends are primarily intended are steel and wrought iron. They may also be used for non·ferrous materials, upon satisfactory qualification of the welding procedure for the particular material.