The seamless square tube is a square steel tube with square and four corners. It is a square steel tube cold drawn and extruded from a seamless steel tube. There is an essential difference between a seamless square tube and a welded square tube. When the bending and torsion strength is the same, the weight is generally lower light.

The material of seamless square tube is mainly Q345 (ASTM A6). and 20#, which are widely used in the manufacture of structural parts and mechanical parts, such as oil drill pipes, automobile drive shafts, bicycle frames, and steel scaffolding used in construction. It can improve the utilization rate of materials, simplify the manufacturing process, and save materials and processing man-hours.

It is widely used in liquid transportation, hydraulic support, mechanical structure, medium and low pressure, high pressure boiler tubes, heat exchange tubes, gas, petroleum and other industries. It is stronger than welded and will not crack.