High-frequency welded round tube is a round tube made by welding metal materials (mainly steel plates) together using the resistance heat effect of high-frequency current, which is then formed into a square tube. In addition, high-frequency welded round tubes can also be transformed into square tubes through "square pushing". "Square pushing" refers to the process of using a sizing force to straighten the steel tube into a square shape.
High-frequency welded square tubes are generally referred to as square rectangular tubes, square tubes, rectangular tubes, etc., named for their square cross-section.
