Steel pipe knowledge: Seamless carbon steel pipe

Seamless carbon steel pipe (English) is made of steel ingots or solid billets made of perforated tubes, and then made by hot rolling, cold rolling or cold drawing. Seamless carbon steel pipe has an important position in China's steel pipe industry.
According to incomplete statistics, there are about 240 seamless carbon steel pipe production enterprises in China, and about 250 sets of seamless carbon steel pipe units, with an annual production capacity of more than 4.5 million tons. From the point of view, <φ76, accounting for 35%, <φ159-650, accounting for 25%. From the perspective of varieties, general-purpose pipes are 1.9 million tons, accounting for 54%; petroleum pipes are 760,000 tons, accounting for 5.7%; hydraulic props and precision pipes are 150,000 tons, accounting for 4.3%; stainless pipes, bearing pipes, and automobile pipes total 50,000 Ton, accounting for 1.4%.
The raw material of the seamless carbon steel tube is a round tube blank. The round tube blank is cut into a length of about 1 meter through a cutting machine, and is sent to a furnace for heating by a conveyor belt. The billets are heated in a furnace and the temperature is about 1200 degrees Celsius. The fuel is hydrogen or acetylene. Furnace temperature control is a key issue. After the tube blanks are released, they are put through the pressure puncher. The most common punching machine is a conical roller puncher. This puncher has high production efficiency, good product quality, large perforation diameter, and can wear a variety of steel types. After piercing, the round billet is successively rolled, rolled or extruded by three rolls. After squeezing, take off the sizing. The sizing machine drills through the cone at a high speed into the steel die to form a steel pipe. The inner diameter of the steel pipe is determined by the outer diameter length of the sizing machine drill. After the steel pipe is sizing, it enters the cooling tower and is cooled by spraying water. After the steel pipe is cooled, it must be straightened. After straightening the steel pipe, it is sent to the metal detector (or hydraulic pressure test) by the conveyor belt for internal inspection. If there are cracks inside the pipe, air bubbles and other problems will be detected. After the quality inspection of steel pipes, strict manual selection is also required. After the quality inspection of the steel pipe, the paint is sprayed with the serial number, specifications and production lot number. And lifted into the warehouse by a crane.
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