Spiral welding refers to bending strips or plates into circular, square and other shapes, and then welding to the surface of steel pipe joints. Welding methods can be divided into different arc welded pipes, high-frequency or low-frequency resistance welded pipes, gas pipes, furnace pipes, Bondi pipes. Pressure seam shape can be divided into longitudinal and spiral welded pipe. Welded steel pipes for petroleum drilling and mechanical manufacturing. Furnace pipe can be used as water gas pipe, large diameter longitudinal welded pipe for high pressure oil and gas transportation, spiral welded pipe for oil and gas transportation, pile, pier, etc. Seamless steel pipe and welded steel pipe have low cost and high production efficiency.
 
Spiral welding has the advantages of simple production process, high production efficiency, low cost and rapid development. The strength of spiral welded pipe is generally higher than that of longitudinal welded pipe, which can reduce the square billet for producing large diameter steel pipe, and can also use the same width steel billet to produce different pipe diameters. But compared with the same length of straight seam weld, the length is 30% to 100%, and the productivity is low. Therefore, most of the smaller diameter pipes are welded by straight seam, and the larger diameter spiral welded pipes provide power.