Causes for and Countermeasures Against Residual Magnet of SAW Spiral Weld Tube

Based on the analysis as described in the paper, it is identified that the occurrence of residual magnet at both ends of the SAW spiral weld tube is related to such elements as chemical composition and structure of the base metal and the welding process. The said residual magnet produces negative influences on product quality.Accordingly, proposals are put forward, including using the Tesla meter for measurement of the residual magnet and eliminating it by means of both AC and DC demagnetization methods.