WELDING BY THE USE OF TWO ELECTRODES PLASMA TORCH

摘要

PURPOSE: A welding method by 2 electrode plasma torches is provided to suppress undercut generation of tail end of the target welding material and improve welding defects on both ends of target welding materials. CONSTITUTION: A welding method by 2 electrode plasma torches comprises the following steps: making array directions of 2 nozzles to be parallel with a welding line; driving one or more ways of torch and target welding materials in a direction according to the welding line; welding the welding line by generating plasma arc from each electrode in each electrode arrangement space; preparing a rear end tap (39a) in the rear end in a welding direction of the target welding material; and keeping plasma arc of a leading pole which precedes in a direction in which the welding line is spread until the plasma arc is stopped after welding in the rear end by an escort pole which escorts in the direction in which the welding line is spread. [Reference numerals] (1) Following keyhole mode(simultaneous ignition at forwarding electrode and following electrode) crater treatment; (3) Normal welding state; (4) Condition change position; (5) Arc stop position; (6) Driving stop position