Carbon steel pipes are divided into hot rolled and cold rolled (drawn) steel pipes.
Hot rolled carbon steel pipe is divided into general steel pipe, low and medium pressure boiler steel pipe, high pressure boiler steel pipe, alloy steel pipe, stainless steel pipe, petroleum cracking pipe, geological steel pipe and other steel pipe.
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 pipe can be up to 6mm, and the wall thickness can be up to 0.25mm. The outer diameter of thin-walled pipe can be up to 5mm, and the wall thickness is less than 0.25mm