According to different production methods, it can be divided into hot rolled tube, cold rolled tube, cold drawn tube, extrusion tube and so on.

1.1 Hot rolled seamless pipes are generally produced on automatic pipe rolling sets.The solid tube blank is checked and cleared of surface defects, cut into the required length, centering on the perforated end face of the tube blank, and then sent to the heating furnace for heating, and perforated on the punch machine.In the perforation at the same time continuous rotation and forward, under the action of the roll and the top, the tube blank gradually formed a cavity, called the wool tube.Then it is sent to the automatic pipe mill to continue rolling.Finally, the wall thickness of the whole machine is adjusted, and the sizing machine is adjusted to meet the specification requirements.It is an advanced method to produce hot rolled seamless steel tube with continuous rolling tube set.

1.2 If you want to obtain seamless tubes with smaller size and better quality, you must use cold rolling, cold drawing or a combination of both methods.Cold rolling is usually carried out on a two-high mill. The steel pipe is rolled in an annular pass consisting of a circular groove with a variable section and a stationary conical top.Cold drawing is usually carried out in 0.5 ~ 100T single chain or double chain cold drawing machine.