SSAW Steel Pipe vs LSAW Steel Pipe

High quality welded steel pipes are mainly produced by three manufacturing processes: SSAW (spiral submerged arc welding), LSAW (longitudinal submerged arc welding) and ERW ( electric resistance welding). Today, we will discuss SSAW and LSAW steel pipe further in aspects of production process and performance.

Production Process:

Both LSAW and SSAW steel pipes are manufactured using JCOE technology. The difference is that the spiral submerged arc welded pipe is welded in a helical or helical position, while the longitudinal submerged arc welded pipe is welded in the longitudinal direction. The manufacturing process of spiral submerged arc welded pipe is to wind and weld the steel strip in a manner inclined to the axis or the center of the pipe, so that the weld seam is helical.

Performance:

1. Spiral submerged arc welded pipe has greater residual stress than LSAW pipe. The straight seam submerged arc welded pipe has been uniformly expanded in diameter.

2. The stress concentration phenomenon of the spiral submerged arc welded pipe weld is serious. The heat-affected zone of the spiral submerged arc welded pipe is larger than that of the straight seam submerged arc welded pipe. The heat-affected zone is considered a weak point where failure may occur.

3. The geometric accuracy of LSAW pipe is better than that of SSAW pipe, which is the key to ease of installation.

4. LSAW pipe has approximately 60% fewer weld lines than SSAW pipe.

5. Using steel plates, the quality of LSAW pipes can be tested by non-destructive testing procedures. The spiral submerged arc welded pipe using hot-rolled coils should be tested by destructive methods such as X-rays.

6. The straight seam submerged arc welded pipe adopts the welding process after forming, and various inspections can be carried out. Spiral submerged arc welded pipes are formed and welded at the same time without pre-inspection.

Overall, the performance of LSAW pipes is better than that of SSAW pipes.

Union Steel Industry is leading manufacturer of SSAW and LSAW steel pipe in China with self own production line. You can check more details on: SSAW Steel Pipe, LSAW Steel Pipe or contact us: sales@union-steels.com