Carbon steel tubes are divided into hot rolled and cold rolled (drawn) steel tubes.
Hot rolled carbon steel tubes are divided into general steel tubes, low and medium pressure boiler tubes, high pressure boiler tubes, alloy steel tubes, stainless steel tubes, petroleum cracking tubes, geological tubes and other steel tubes.
Cold rolled (dial) carbon steel pipe in addition to general steel pipe, low and medium pressure boiler steel pipe, high pressure boiler steel pipe, alloy steel pipe, stainless steel pipe, petroleum cracking pipe, other steel pipe, also includes carbon thin wall steel pipe, alloy thin wall steel pipe, stainless steel pipe, special-shaped steel pipe. The outer diameter of hot rolled seamless pipe is generally greater than 32mm and the wall thickness is 2.5-75mm. The outer diameter of cold rolled seamless steel pipe can reach 6mm and the wall thickness can reach 0.25mm. The outer diameter of thin-walled pipe can reach 5mm and the wall thickness is less than 0.25mm.
General carbon steel pipe: 10, 20, 30, 35, 45 and other high-quality carbon bonded steel 16Mn, 5MnV low alloy structural steel or 40Cr, 30CrMnSi, 45Mn2, 40MnB and other alloy steel hot rolled or cold rolled. 10, 20 and other low carbon steel manufacturing seamless pipe is mainly used for fluid pipeline. 45, 40Cr and other medium carbon steel made of seamless pipe to manufacture mechanical parts, such as cars, tractors stressed parts. The general use of carbon steel pipe to ensure the strength and flattening test. Hot rolled steel pipes are delivered in hot rolled or heat treated condition. Cold rolled delivery is heat -
treated.