Circular pulling through

Pull-off and acceleration forces have to be applied when processing endless material. The forces and moments required can be generated in various ways. Technical solutions in widespread use include:

1. linear pull-offs with clamping devices,
2. driven rolls,
3. drive chains or toothed belts,
4. circular pulling through units

A circular pulling through unit consists of a driven pulley against which the material to be straightened is pressed as the result of a partial or full wrap. Movement is produced by an interference fit between the pulley and the material. The following aspects should be noted:

1. The material to be straightened is bent and deflected. This can lead to changes in its curvature!
2. The maximal tensile force depends on the contact force and on the conditions of friction.
3. The useful pull-off force depends on the pulley radius and the driving torque.