Manufacturing Technology of Seamless Steel Tube for Thick-walled Steel Tube and Thick-walled Steel Tube:
Hot rolled (extruded seamless steel tube) round billet heating piercing three roll cross rolling, continuous rolling or extrusion pipe removal sizing (or reducing diameter) cooling straightening hydraulic test (or flaw detection) marking storage.
The raw material for rolling seamless tube is round tube billet. It is heated by conveyor belt. The billet is fed into the furnace and heated to about 1200 C. Fuel is hydrogen or acetylene. Furnace temperature control is a key problem. After the tube blank is released, it is punched through a pressure punch.
A more common punch is a tapered roller punch. The perforator has high production efficiency, good product quality, large perforation diameter, and can wear various steel grades. After piercing, the round billet is rolled or extruded continuously by three rolls. After extrusion, the pipe should be sizing. The finishing machine rotates to the steel core at high speed through a conical drill to form steel pipe. The inner diameter of steel pipe is determined by the outer diameter of the drill bit of the sizing machine. After the size of the steel tube is determined, it enters the cooling tower and is cooled by spraying water. Straighten the steel tube after cooling. After the steel pipe is straightened, it is sent to the metal flaw detector (or hydraulic test) through the conveyor belt for internal flaw detection. If there are cracks in the steel pipe, bubbles and other problems will be detected. After quality inspection of steel pipes, they must be carefully selected by hand. After quality inspection of steel pipe, the quantity, specification and batch number of paint sprayed are hoisted into warehouse by crane.