The rolling rolls for the universal rolling mill for steel are mainly divided into working rolls, backup rolls and intermediate rolls, and are different from ordinary rolling mills. The number of rolls is generally two heads, four intermediate rolls and three working rolls, or two heads and three intermediate rolls, or three working rolls and no intermediate rolls.
1. Working Roll
The working rolls are the main rolls that accept workpiece material load during the rolling process. It is provided with good surface quality and shaped according to the shape of the required profile. Excessive friction on the surface of the rolls can cause them to be damaged or even broken due to the high temperature generated. Therefore, materials with high wear resistance and excellent temperature resistance are usually selected as the material of the working rolls. For example, 9Cr2Mo is usually used in rough rolling, H12 ~ 16 grades in the middle rolling, and 3Cr2Mo for the finished rolling.
2. Backup Roll
Backup roll is a kind of large diameter roll which provides more support for the work roll during rolling. Its design parameters mainly include roll material, roll diameter, roll length, roll shaft diameter, roll neck profile and roll etching pattern. The roll diameter is usually determined by the maximum gap of the rolling mill. The roll length is determined by the size of the rolling mill and the maximum roll bite length. The roll shaft diameter depends on the roll diameter, the roll material and the geometrical shape of the rolling mill. The roll neck profile mainly depends on the shape of the working rolls. The knurling pattern is usually fine in rough rolling and medium in intermediate and finish rolling.
3. Intermediate Roll
The intermediate roll is used to transfer the rolling force between the work roll and the backup roll. It is designed to have a large amount of radial movement and axial movement to control the contact pressure between the work roll and the backup roll. The material of the intermediate roll is usually selected to have high plasticity and strength.
The rolling rolls of the universal rolling mill for steel are not only designed differently from ordinary rolling mill, but also have much stricter requirements during use. Therefore, when selecting materials, it is necessary to consider their performance characteristics such as wear resistance, temperature resistance and corrosion resistance, in order to ensure that the rolling rolls of the universal rolling mill for steel can meet the needs of the actual service.
