How circumferential piston pumps work

External Circumferential Piston (ECP) pumps are different to rotary lobe pumps.They operate on the circumferential piston principle whereby arc shaped rotor wings (pistons), travel in annular shaped cylinders machined in the pump body. This results in a long sealing path, wide inlet/outlet orifices and large fluid cavities.

In addition to this Waukesha Universal ECP pumps have rotor wings are manufacturered to extremely close tolerances from non gauling Alloy 88 and are designed with no cavity between the rotors, as is the case with rotary lobe pumps, to allow the passage of fluid.