The Difference between Straight Seam Steel Pipe and Spiral Steel Pipe

　　1. From the processing point of view: straight seam steel pipe is made of steel plate with a certain width into cylinder, and then welded to form, the equipment is relatively simple, and the productivity is also high. Spiral steel pipe is made by winding a certain width of steel plate into a cylinder, then welding, forming, equipment is more complex, at the same time, because the weld is much longer than the straight seam steel pipe, so the productivity is relatively low.

　　2. From the strength point of view: after welding, the internal stress of straight seam steel pipe distributes along the weld, while the internal stress of ASTM A53 SSAW Sch 40 Spiral Steel Pipe distributes uniformly along the axial and radial direction, which can better partially offset the pressure. So in terms of pressure resistance, spiral steel pipe is stronger.