straight welded pipe and spiral welded pipe are both kind of welded steel pipe, they play a very big role in national construction work. There are many difference between straight welded pipe and spiral welded pipe because of their different manufacturing technique. The production process of straight welded pipe is relatively simple, The main production processes are high frequency welded straight seam welded pipe and submerged arc welding straight seam welded pipe, straight seam welded pipe has high production efficiency, low cost and fast development. The strength of spiral welded pipe is generally high with straight seam welded pipe, It is also possible to produce welded pipes with larger diameters with narrower billets.  However, compared with the straight welded pipe of the same length, the weld length is increased by 30%-100%, and the production speed is relatively low. Therefore, the welding pipe with smaller diameter is mostly straight seam welding, while the welding pipe with larger diameter is mostly spiral welding.