Carbon steel pipe can be divided into seamless steel pipe, straight seam steel pipe, spiral steel pipe, high-frequency welded steel pipe. Rolled seamless carbon steel pipe is the raw material of round tube, tube embryo to be cut through the cutting machine into a length of about 1 m of blank, and the conveyor belt to the furnace heating. The billet is fed into a furnace and heated at a temperature of about 1200 degrees Celsius. The fuel is hydrogen or acetylene. Furnace temperature control is a key issue. After the round tube billet to go through the pressure piercing machine to wear empty. Generally more common punching machine is conical roller piercing machine, this punching machine production efficiency is high, product quality is good, perforation expansion diameter large, can wear a variety of steel. After piercing, the round tube blank has been three-roll cross-rolling, rolling or extrusion. Squeeze after the tube diameter. Sizing machine through the high-speed rotation of the cone drill bit into the steel embryo drilling, the formation of steel pipe. The inner diameter of the pipe is determined by the outside diameter of the sizing bit. Steel pipe after sizing, into the cooling tower, through the water cooling, the cooling pipe, it is necessary to be straightened. After straightening by the steel pipe sent to the metal detector (or water pressure test) for internal testing. If the pipe has cracks, bubbles and other problems, will be detected. After the quality of steel pipe but also through rigorous manual selection. After the quality inspection of steel pipe, spray paint with the number, size, production lot number. And suspended by the crane into the warehouse.
Cold drawn (rolled) carbon steel seamless steel pipe: round tube → heating → punching → start → annealing → pickling → oiling (copper) → multi-pass cold drawing (cold rolling) → tube → heat treatment → straightening → water pressure test (testing) → marking → storage
Carbon steel seamless steel pipe because of its manufacturing process is different, is divided into hot-rolled (extrusion) seamless steel tubes and cold drawn (rolled) seamless steel pipe two. Cold drawn (rolled) tube is divided into two kinds of round tube and special-shaped tube.
In addition, GB / T17396-1998 (hot-rolled seamless steel pipe for hydraulic support), GB3093-1986 (diesel engine high-pressure seamless steel pipe), GB / T3639-1983 (cold drawn or cold-rolled precision seamless steel pipe), GB / T3094-1986 (cold drawn seamless steel pipe shaped steel pipe), GB / T8713-1988 (hydraulic and pneumatic cylinder with precision diameter seamless steel pipe), GB13296-1991 (boiler, heat exchanger with stainless steel seamless pipe), GB / T14975 (Seamless Steel Tube for Automotive Axle Bushings), API SPEC5CT-1999 (Casing and Tubing), GB / T14976-1994 (Seamless Steel Pipe for Fluid Conveying) Specification) and so on.