PROGRESS IN MANUFACTURE TECHNOLOGY FOR WELDED STEEL TUBES

Quality of electric welded-steel pipes has been improved considerably owing to progresses made in such aspects as forming, welding, post-welding annealing and quality assurance,etc. The ERW+SR hi-frequency, hot-continous welder process which replaces the conventional continuous welding process has improved surface quality of the product and enhanced the applicability thereof; both the welded-tube OD circumference auto-measuring system and the weld-seam auto-control system have further ensured the quality of the spiral welded-pipe; the introduction of the computer automatic-tracking system and upgrading of the equipment automation level have perfect the technology of straight welded-pipe manufacture and thus enhanced the productivity.