backing strip for welding pipe the backing strip feed apparatus and arc welding apparatus for use with the backing strip apparatus

摘要

PURPOSE: Provided are backing strip for welding pipe, backing strip feed apparatus and arc welding apparatus for use with backing strip apparatus to easily perform the welding process by repeatedly using the backing strip regardless difference of diametric sizes between two pipes welded. CONSTITUTION: The backing strip(400) has a simple construction of an outer peripheral side, a circular plate with an opening at one portion of the peripheral side, and a wedge to be inserted into/removed from the opening. The backing strip feed apparatus(500) comprises a support with a guiding part; a sliding bar to move along the guiding part; and a securing component to fix the sliding bar to the support. The arc welding apparatus comprises a pair of rollers(210, 210'); a pressure roller(230) for pipes(100, 100'); a welding torch(310); a transfer component(320) for the torch; a wire supplying device(330); the backing strip(400); the shifting device for the backing strip; welding power to supply power to the wire supplying device; and a power controller(700).