Self-priming diaphragm pumps
Ideal for pumping thick, muddy, abrasive liquids with solids in suspension.
Often used for smaller wellpointing applications such as installing small pump chambers, where a vacuum prime centrifugal pump is too large.
The system consists of a diaphragm guided by a coupling rod. The flow generated by the movement of the diaphragm is controlled by check valves at the suction and delivery.
As the diaphragm rises away from the bottom of the casing it produces a vacuum which draws the liquid into the casing through the suction valve. When the diaphragm is on the downstroke, the liquid is expelled through the delivery valve.