In the V (variable) type decanter centrifuge, the motion is transmitted to the bowl by means of one electric motor driven by an inverter. The same motor powers a hydraulic pump system, which, by means of a hydraulic motor, rotates the screw.
The variation of the screw rotation speed is continuous and automatic and it takes place through two procedures:
- at constant rotation (the differential rotation is constant and the transmission power depends on the percentage of input solid);
- at constant torque (the modulation of the differential revs. depends on the percentage of input solid).
The working principle of the decanter centrifuge is based on the specific weight difference of the solid-liquid substances to treat.
The separation takes place in the bowl, which rotates at high speed and multiplies thousands of times the force of gravity. The screw’s function is to put out the solid, which deposits in the bowl.