Welded steel pipe and seamless steel pipe have significant differences in forming process, appearance and performance, application field, etc. ‌

Forming process ‌Seamless steel pipe‌: Made by perforating steel ingot or solid tube billet, and then processed by hot rolling, cold rolling or cold drawing. Its production process includes steps such as heating cylinder, inserting mandrel tool, rolling and stretching until the required pipe size and wall thickness are reached. This process makes the seamless steel pipe seamless on the surface and has better overall performance. ‌

‌Welded steel pipe‌: Originally a flat steel plate, it was molded into a tubular shape and then welded on both sides. Modern technologies such as high-frequency current welding have greatly improved the quality of welds, so that welded steel pipes can meet a variety of needs in appearance and performance.

Appearance and performance ‌Seamless steel pipe‌: Rolled once, with high surface finish, no oxide layer on the inner and outer walls, and can withstand high pressure without leakage. High precision can be used in various high-pressure equipment.

‌Welded steel pipe‌: There are weld ribs on the inner wall. The presence of welds may affect the smoothness of fluid flow to a certain extent, but modern welding technology can ensure the quality of welds, so that it can perform well in a variety of applications. ‌

Application fields ‌Seamless steel pipe‌: Due to its excellent mechanical properties, high tensile strength, heat resistance and corrosion resistance, seamless steel pipes are widely used in petroleum, chemical, electric power, machinery and other industries. Specifically, it can be used for petroleum geological drilling pipes, petrochemical cracking pipes, boiler pipes, bearing pipes, and high-precision structural steel pipes for automobiles, tractors, and aviation. ‌Welded steel pipe‌: Due to its low cost, high production efficiency, good plasticity and machinabi