SSAW vs. LSAW Steel Pipe

Spiral steel pipes (SSAW pipe) and straight seam steel pipes (ERW/LSAW pipe) are currently widely used in water pipelines, construction and other industries, but there is a big difference between the two.

SSAW vs LSAW steel Pipe:
1) Different pressure-bearing capacity
The strength of spiral steel pipes is generally higher than that of straight seam steel pipes. The main production process is submerged arc welding. Spiral steel pipes can use blanks of the same width to produce steel pipes with different pipe diameters, and can also use narrower blanks to produce steel pipes with larger pipe diameters.

2) Different specifications
The specifications of spiral steel pipes are generally above 219mm, and most of them are of large diameter. The specifications of straight seam steel pipes are mostly of small diameter, but some manufacturers also have many large diameters.

3) Different prices

Spiral steel pipes are mostly settled by measuring rulers, and the price of straight seam steel pipes is mostly settled by weighing, but the price of spiral steel pipes is about 300 yuan/ton cheaper than the price of straight seamed steel pipes.

The process difference between straight seam steel pipe and spiral steel pipe:
1. From the processing point of view: the straight seam steel pipe is a steel plate of a certain width that is bent into a tube and then welded to form it. There is only one weld in the middle of the straight seam steel pipe. The equipment is relatively simple and the productivity is high. Spiral steel pipes are formed by winding steel plates of a certain width into a tube and then welding them to form. It is formed by double-sided submerged arc welding. The equipment is more complicated. At the same time, because the weld seam is much longer than the straight seam steel pipe, the productivity is relatively low.

2. From the perspective of strength: After the longitudinal seam steel pipe is welded, its internal stress is distributed along the weld seam, while the internal stress of the spiral steel pipe after welding is evenly distributed in the axial and radial directions, which can better partially offset the pressure it bears. Therefore, in terms of pressure resistance, the spiral steel pipe is stronger.

Tips: Straight seam steel pipe is a steel pipe whose weld seam is parallel to the longitudinal direction of the steel pipe. Straight seam steel pipes can be divided into high-frequency straight seam steel pipes (ERW Pipe) and submerged arc welded straight seam steel pipes (LSAW) according to the production process. Straight seam welded pipe has simple production process, high production efficiency, low cost and rapid development.

ERW welded pipe is formed by rolling strip and welding the seam, with tighter dimensional tolerances and less weight. The weld seam is heat treated after welding that no untempered martensite remains, and the weld flash can be removed from both inner and outer surfaces.