Hot Rolling Mill: The Cornerstone Of Metal Forming in Modern Industry

Hot rolling mills, as the core equipment of the metallurgical industry, are heavy machinery that processes metal materials through high-temperature plastic deformation. Its working principle is to heat the metal billet to the recrystallization temperature (usually the steel billet needs to reach 1100-1250℃), and under the continuous rolling action of the rolls, it undergoes plastic deformation, eventually forming industrial semi-finished products such as plates, strips and sections. Compared with the cold rolling process, hot rolling has significant advantages such as low energy consumption and high processing rate.
I. Equipment Composition and Workflow
A typical hot rolling unit consists of four major modules: the heating furnace, the rough rolling unit, the finishing rolling unit and the cooling system.
Heating furnace: It adopts a step-by-step or push-steel structure to uniformly heat the continuous casting billet to the austenitic state.
Rough rolling mill: Through 4-6 passes of rolling, the 200-300mm thick slab is thinned to 30-50mm.
Finishing mill group: The 7-stand continuous rolling mill rolls the intermediate billets into finished products ranging from 1.2 to 25mm.
Laminar cooling: Control the cooling rate to adjust the microstructure of steel.
Ii. Key Technical Features
High-temperature rolling: By taking advantage of the characteristic that the deformation resistance of metals decreases at high temperatures, a single-pass reduction rate of over 70% can be achieved.
Automation control: Modern hot rolling lines are equipped with intelligent modules such as AGC (Automatic Thickness Control) and plate shape closed-loop systems;
Scale benefits: The annual production capacity of a single 2250mm hot continuous rolling line can reach 5 million tons.
Iii. Main Products and Application Fields
Hot-rolled coil: Used for manufacturing structural components such as welded pipes and automotive frame steel;
Hot-rolled profiles: H-beams, steel rails and other building materials;
Hot-rolled special steel: Specialized materials for boiler plates, container plates, etc.
With the application of new technologies such as TMCP (Thermal Mechanical Control Process), modern hot rolling mills have developed into a precision production system integrating metallurgy, machinery and automation.