LSAW steel pipe (UOE, JCOE) manufacturing process, welding process settings continue to advance. Its function is to shape, shape and locate the weld seam on the back cover, to ensure the size of the pipeline, and to benefit the quality and production efficiency of the welded pipe.


Pre-welding process
Through the next drum conveyor, the pipe is transported to the cutting torch of the pre-welder, the rising rotating roll, the rotating adjustment opening position, the top welding on both sides of the pressure roll and the pressure roll, so as to make the pipe seam, drop the gun and adjust the tracking of the welding seam, open the protective gas and cooling water, start welding, monitor the welding state, and stop the welding arc at the pipe end (automatic delay stopping gas). Hoist gun and top pressure roll, pre-welded pipe welder, pipe end and welding defects.


Pre-welding process characteristics
Ar + CO2 hybrid gas shielded arc welding is used for pre-welding, and the continuous weld on the back of the pipe moves faster. Because of the oblique angle, the shape of the tube, the deformation factors along the longitudinal opening and both sides of the plate edge are different, the quality of the seam behind the seam is unstable and varies greatly. It is necessary to change the seam welding, the arc is in a stable state, and the welding position deviates from the shell, etc. to track and adjust in real time. Therefore, pre-welding has the characteristics of welding speed, impact seam quality factors, change and adjustment randomness