Carbon seamless steel pipe is generally produced in the automatic rolling unit. Check the solid billet and remove it from the surface defect. Cut it into the required length. At the end of the tube at the central perforation end, it is heated in the furnace and perforated in the punch. Perforation occurs when the tube continues to rotate and move. Under the action of rolling and head, the cavity gradually forms, which is called capillary. Then it is sent to the automatic rolling mill to continue rolling. Finally, the whole wall thickness of the whole machine, through the sizing machine diameter, to achieve specifications. It is a more advanced method to produce hot-rolled seamless steel tube by continuous rolling mill.


If you want to get smaller and better quality seamless tubes, you must combine cold rolling, cold drawing or two methods. Cold rolling is usually carried out on a twin-roll mill, where steel pipes are rolled in a circular hole formed by a conical hole and a fixed conical head. Cold drawing is usually carried out on single-chain or double-chain cold-drawing machines ranging from 0.5 to 100T.


The extrusion method is to place a heated tube in a closed extrusion cylinder, which moves with the extrusion rod to extrude the extrudate from a smaller die hole. This method can produce steel pipe with smaller diameter.