LSAW and SSAW are variants of SAW (submerged arc welded) pipes. The difference between them is the way they are welded. In LSAW pipes, the welding is longitudinal, which means that steel (hot rolled coil plate) is rolled into a pipe and the seam is welded longitudinally. In the SSAW type, steel coils are welded spirally, like a helix, so that the coil (strip) assumes the shape of a pipe. SAW pipes are used mainly in oil and gas transportation. On the other hand, seamless (non-welded) pipes are mainly application in oil and gas exploration projects.

An LSAW pipe (“submerged arc welding”) is manufactured by cutting, bending, and welding steel plates (JCOE process). The two main types of LSAW pipes are the longitudinal (with a single or double straight seam weld, DSAW) and the spiral type (called, HSAW, SSAW or SAWL pipe).

ASTM A252 打桩管在建筑物和挡土墙中的应用

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

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 pipe is about 300 yuan/ton cheaper than that of straight seam steel pipe.