The thin-walled tube is made of steel ingot solid tube blank by piercing, then by hot rolling, cold rolling cold drawing. Thin walled pipe plays an important role in steel pipe industry in China. The raw material of thin-walled tube is round tube blank. The round tube blank is cut by a cutting machine, the blank with a length of about 1 meter is sent to the furnace for heating by a conveyor belt.

The billet is heated in a furnace at about 1200 ℃. The fuel is hydrogen acetylene. The temperature control in the furnace is the key problem. After the round tube is discharged the furnace, it needs to be pierced by the pressure piercer. Generally, the more common piercer is cone roll piercer. This kind of piercer has high production efficiency, good product quality, large amount of piercing expanding, can wear a variety of steel grades. After piercing, the round billet is successively rolled by three roll cross rolling, continuous rolling extrusion. After extrusion, take off the pipe determine the diameter. The sizing machine rotates into the steel embryo at high speed through a conical drill to form a steel pipe. The inner diameter of the steel pipe is determined by the length of the outer diameter of the drill bit of the sizing machine. After sizing, the steel pipe enters the cooling tower is cooled by water spraying. After cooling, the steel pipe will be straightened. After straightening, the steel pipe is sent by conveyor belt to metal flaw detector ( hydraulic test) for internal flaw detection. If there are cracks, bubbles other problems inside the steel pipe, it will be detected. After quality inspection, the steel pipe should be strictly selected by hand. After the quality inspection of the steel pipe, the number, specification, production batch number, etc. shall be sprayed with paint. It is hoisted into the warehouse by crane.