Roll forming is an ongoing bending procedure in which a lengthy strip of sheet steel (normally coiled metal) is passed via rolls mounted on consecutive stands, each set executing only an incremental component of the bend, till the preferred cross-part profile is obtained. Roll forming is perfect for generating continuous-profile components with long lengths and in big quantities.
Three-high rolling mills consist of a large back up roll, small work roll, and another large back up roll. The purpose is to have a very minimum amount of reduction. Three-high mills are commonly used for making bearing material for gasoline and diesel engines.
Mechanical screwdowns are still used for small mill reducing and large mills for cogging and hot plate reducing where accuracy is not a precision factor, and where fire may be a concern. However, hydraulics can now be water hydraulics. By adding chemicals in the water, you have a hydraulic system that will not catch fire. However, water hydraulics require limited low pressure, and they are high in maintenance and many customers still prefer mechanical screwdowns
The main advantage of a dual motor drive is that each work roll is individually driven. If one roll gets damaged and needs to be ground down, the other roll does not have to be ground down to the same diameter. This allows each motor drive to compensate for the different diameters.
