Abstract: During the repeatedly-expanding process of the SAWL pipe,among the operation tools of the mechanical expanding machine,the taper part is often damaged,and thus needs to be repaired. However at present no satisfactory repair technique for seriously damaged taper tool is available at home. Elaborated in the article are different methods for repairing the wear parts used as operation tools of the said expanding machine. The application scope,and advantages and disadvantages of each of the methods is analyzed and summarized. As a result,two repair methods which are suitable for relevant domestic manufacturers are proposed,i.e.,the electric brush-coating process and the combined process of laser fusion coating + hot spray coating.