Welded pipe is a common seen pipe which usually be used on fluid conveyance. Generally, it is defined to as the large diameter solder pipe, in accordance with the welding as a way for tube, the solder steel pipe consist spiral pipe and straight seam welding tube.

Based on the application, it can be divided into general welded pipe, galvanized welded tube, oxygen blowing metric pipe, welded tubes, wire casing, roller tube, deep well pump tubes, auto tube, transformer, electric soldering thin wall pipe, welded pipe and spiral welded tube.

Spiral welded pipe is the low carbon structural steel and low alloy structural steel strip according to certain helix Angle rolled into a tube billet, and then solder pipe joints made up, it can use a narrow strip in the production of large diameter steel tube, straight seam solder pipe is hot rolled plate after molding machine molding, roll deformation of steel coil for round cylinder, using frequent current skin effect and proximity effect or flux layer burning under the arc soldering, the tube billet is heated to melt, and fusion under certain extrusion effect, after the final cooling forming.

Welded tube is made of steel plate or steel strip after crimp forming, and then after welding. Divided into the form of the weld seam welded tube and spiral welded pipe, straight seam steel tube forming technique of common UOE forming process, JCOE steel pipe forming process.