The raw material of the carbon steel pipe is a round tube blank, and the round tube embryo is cut by the cutting machine and the growth of the blank is about 1 meter, and is sent to the furnace by the conveyor belt for heating. The billets are heated in a furnace at a temperature of about 1200 degrees Celsius. The fuel is hydrogen or acetylene. The temperature control in the furnace is the key problem. After the round tube billet is released, it must be perforated by the pressure piercing machine. Generally, the most common piercing machine is the conical roll piercing machine, which has high production efficiency, good product quality, large perforating and expanding diameter, and can wear a variety of steel. After the perforation, the round tube blank is successively rolled by three roller skew, continuous rolling or extrusion. After extrusion, the tube should be removed for sizing. The sizing machine rotates into the steel embryo at high speed through the conical drill to punch holes and form the steel pipe. The inner diameter of the steel pipe is determined by the outer diameter length of the caliper drill bit. After the steel pipe is calibrated, it enters the cooling tower and is cooled by water spray. After the steel pipe is cooled, it will be straightened. After the steel pipe is straightened, it is sent to the metal inspection machine (or hydraulic test) for internal inspection. If there are cracks, bubbles and other problems inside the steel pipe, it will be detected. After the steel pipe inspection, it is also strictly selected by hand. After the steel pipe quality inspection, paint the number, specification, production batch number, etc. And hoisted by crane into the warehouse.