Optimization of Dual-torch Pipe-flange Welding Process

Pipe spools, which are used in various industrial fields, such as shipbuilding and marine plants, marine piping water pipes, fire pipes, ventilation pipes, structural pipes, and district heating, are mostly composed of medium to large pipes. In the pipe-flange welding process, the inside and outside of the flange are welded after temporary welding. However, the deformation difference may be large depending on the work procedure, and the error then increases when completing the pipe spool in the subsequent process. Therefore, a dual welding device that welds the inside and outside of the flange simultaneously has been developed and applied to the field. This study develops a pipe-flange joining method using GMA welding and attempts to optimize the welding process.