Hot-rolled carbon steel pipes are divided into general steel pipes, low and medium pressure boiler steel pipes, high pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, geological steel pipes and other steel pipes.
In addition to general steel pipes, low and medium pressure boiler steel pipes, high pressure boiler steel pipes, alloy steel pipes, stainless steel pipes, petroleum cracking pipes, and other steel pipes, cold-rolled (dial) carbon steel pipes also include carbon thin-walled steel pipes, alloy thin-walled steel pipes, Rust thin-walled steel pipes, special-shaped steel pipes. 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. Cold rolling has higher dimensional accuracy than hot rolling.

Stainless steel always presents various forms of panel standards

And cold-rolled coil (annealed state): it is obtained by bell-type annealing before the chilled coil is rolled. After annealing, its work hardening phenomenon, that is, the decrease in yield strength is close to that before cold rolling.