Rectangular tube is a type of hollow strip steel, also known as flat tube, square tube, or square flat tube (as the name suggests). When the bending and torsional strength are the same, the weight is relatively light, so it is widely used in the manufacturing of mechanical parts and engineering structures.
Classification of rectangular pipes: Steel pipes are divided into seamless steel pipes and welded steel pipes (welded pipes). Hot rolled seamless square pipes, cold drawn seamless square pipes, extruded seamless square pipes, and welded square pipes.
The welded square tube is further divided into:
1. Divided by process - electric arc welding square tube, resistance welding square tube (high-frequency, low-frequency), gas welding square tube, furnace welding square tube;
2. Divided by weld seam - straight seam welded square pipe, spiral welded square pipe.
