Control Measures for Straight-edge Defect of JCOE SAWL Steel Pipe

Briefed here in the paper are the straight-edge defect of the JCOE SAWL pipe and the measurement method for such defect.The causes for such defect are analyzed.Accordingly relevant countermeasures are proposed,including controlling warpage deformation,setting the reduction by the pipe-forming station operator based on the information about the steel plate strength,optimizing the pipe-forming parameter,properly using the expanding die to control the length of the section that is not fully bent,and periodically changing the worn copper sliding block of the expanding mill,etc.Thanks to the above mentioned countermeasures,the pipe-end straight-edges of pipes with different sizes can be properly limited under 0.7 mm.