Expanding chucks are used to ensure that a reel of paper or other material adheres to a brake or drive during boyh winding and unwinding.

All Casrem mechanical chucks make use of the following operating principle: an eccentric at the centre of the spindle which, by means of twisting moment generated by braking action and drive, rotates - with respect to the sector-guides - and pushed the expansion elements (sectors) toward the reel-core.
With this system, locking is obtained by a force directly in proportion to the twisting moment, thus ensuring sure locking under all work conditions.The reel is automatically centred. The PM series pneumatic chucks have the same characteristics as the mechanical ones, but, in this case, drive is obtained by air pressure.

-  Securing flange to clientís specifications built in a single piece incorporating the spindle carrying and drive axis.
-  A thrust-resisting flange on the sector-guide ensures reliable expansion even if there are axial loads.
-  Expansion sectors with a large contact surface in order not to deform or damage the core if strong loads are applied.
-  Automatic locking in both rotation directions, without the operator intervening.
-  Guaranteed operation even with axial loads or low torque values.
-  High expansion and core locking thanks to the configuration of the eccentric and grooves on the sectors.
-  Low losses due to two thrust ball-bearings.
-  No maintenance thanks to sealed bearings and calculated tollerance.
And thatís not all: thereís our special protective treatment applied to all the chucks we produce and aimed at preventing oxidation.

Expanding core chucks are mainly used in the paper industry on printing machines, rolling machines, cutters, unwinders, rewinder and re-reeler cutters.