PISTON PUMPS are of two different models, pneumatic for low flow rate and hydraulic for higher ones.

The range of pneumatic piston pumps is made up of three models; the pneumatic cylinder is operated from compressed air through a pneumatic distribution group, which controls the movement.

The hydraulic piston pumps are manufactured in two models, the hydraulic cylinder is actuated by an hydraulic power unit mounted on board of the pump, by means of an hydraulic distribution group that controls its movement.

The oil or air under pressure acts through a distributor on the double-acting cylinder generating a "movement to and fro" on the steel piston with ceramic coating.

The piston, accompanied by the suction and delivery valves, exercises a suction and pressing effect which determines the pumping of the slurries, up to the maximum pressure of 16 Bar.

The typical characteristic of these pumps, in the specific case of filtering, is their ability to adapt to the condition of the filter press at any moment, as follows:

when a filter is empty the pump feeds it at the maximum flow;

as the filtering proceeds and filter is progressively filled up, the filtering pressure increases and the flow rate of the pump is automatically reduced until it reaches zero setting, that corresponds to the pump calibration pressure and to the end of filtering.

In this way the slurry is constantly fed to the filter at the maximum pressure for that moment, without intermediary stops.

The end result is a better sludge dewatering of the pressed cakes.