Automatic feeding and rotating for pipe jointing machine.
The paper presents pipe butt welding processes in steam boiler production. Beside conventional MMA (Metal-arc welding with covered electrode) process, automatic TIG (Tungsten inert gas arc welding) process when pipes rotate during the welding (the welding head is motionless), and automatic orbital TIG welding when welding head rotates during the welding (pipes are motionless), are explained. The first described automatic TIG welding process is single pass welding process, and the second is multi pass welding process. Beside cost efficiency observation, examples of successfully applied automatic welding processes of butt tube welding in steam boiler production are given corroborated with the results of the mechanical tests.