A Rollar Crusher is based on the principle of feeding the material to be crushed between two manganese steel cast rollers rotating in opposite directions, with their axes parallel to each other. The gap setting between the rolls is very small and hence the feed material is sushed while it passes through them. The central axis of one roll is fixed while the other is of floating design The floating roll gives way to any uncrushable material that falls in the feed opening.

A double roll crusher may be categorised as SMOOTH / SMOOTH AND CORRUGATED / CORRUGATED double roll crusher depending on the corrugation on none one or both rolls respectively.

The shalt on which the rolls are mounted is of special steel and is carried in self aligning cylindrical double roller bearings of adequate size and capacity, fitted in housings and well sealed with labyrinths to prevent possible entry of dust, foreign particles or moisture.

The gap between the rolls can be adjusted with the help of setting the position of the floating roll. This is cone by adjustment bolts and insertion or removal of steel strips provided with the equipment.

Drive to both rolls is through individual flywheels which may be driven by s single motor or separately by two motors.