The welding process of the erw pipe is to use the skin-receiving principle generated by the high-frequency current to heat the edge of the hot-rolled coil to a molten state, and then perform welding by a mechanical extrusion method.

Compared with traditional pipe, seamless steel pipe has lighter material, high strength, good resistance, can withstand high internal pressure, is sensitive to production, and can be used in messy or harsh geological conditions. However, there are drawbacks in the use process, mainly because the internal and external anti-corrosion treatment is more troublesome.