Billet refers to semi-finished products used to produce steel, which cannot be directly used by society. Billet and steel are strictly divided according to the standard, which cannot be determined by whether it is the final product of the enterprise, but should be implemented according to the unified standard of the whole society.

Continuous cast steel square billet and rectangular billet are mainly represented by plain carbon steel, low carbon and low silicon cold rolled material, high-quality carbon structural steel, low alloy high strength steel, special steel grades, etc.