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Hot Rolling Mill
A rolling mill is a device meant for pressure shaping of the metals or other materials between the rotating rolls. It is basically an automatic system or cluster of machines to perform both rolling and auxiliary operations including transportation of billets to heating furnaces and mill rolls, rolled material, metal after rolling, and many other functions. When rolled, the metal is first passed through a hot rolling mill. The metal is passed several times through it due to which the thickness of the metal considerably reduces.
The main purpose of this mill is to repeatedly heat the semi-finished steel or any other metal slab to nearly their melting points. It then rolls them thinner and longer with the help of successive rolling stands driven by the motors and finally coils the straightened sheet to be transported to the next process. It can roll slabs weighing up to 30 tons, 8 to 9 inches thick steel slabs and up to 36 feet long into fine strips of thickness 1/16 inches.
The mill rolls out coils by subjecting the slabs to extremely high temperatures in a heating furnace and high pressures through a successive arrangement of rolls. Because of the application of extremely high temperatures and pressures, the rolls which stay in contact with the hot steel band worn out. The continuous wear of roll adversely affects the fabrication and tolerances of the rolled products. In order to build resistance to breakage during the process, some rolls are replaced after every shift. However, change in the pressure settings of these rolls increases the possibility of obtaining low quality standards.
Some advantages:
The main purpose of this mill is to repeatedly heat the semi-finished steel or any other metal slab to nearly their melting points. It then rolls them thinner and longer with the help of successive rolling stands driven by the motors and finally coils the straightened sheet to be transported to the next process. It can roll slabs weighing up to 30 tons, 8 to 9 inches thick steel slabs and up to 36 feet long into fine strips of thickness 1/16 inches.
The mill rolls out coils by subjecting the slabs to extremely high temperatures in a heating furnace and high pressures through a successive arrangement of rolls. Because of the application of extremely high temperatures and pressures, the rolls which stay in contact with the hot steel band worn out. The continuous wear of roll adversely affects the fabrication and tolerances of the rolled products. In order to build resistance to breakage during the process, some rolls are replaced after every shift. However, change in the pressure settings of these rolls increases the possibility of obtaining low quality standards.
Some advantages:
- Less force
- Greater degree of deformation
- Improved structure and properties of the metal
- No Hardening
- High resource input & costs for heating
- Increased wear and reduced standing time
- Continuous maintenance
