In this pump design, all rotating parts (shaft, rotor, impeller) are located within the can in the pumped medium. Cooling and lubrication is provided by the pumped medium.
The NPSH curve displays the minimum required inlet pressure (expressed in m) allowing the pump to pump in accordance with the performance curve and in order to prevent evaporation of the pumped fluid so as to avoid cavitation inside the pump.
Cavitation is the formation and abrupt collapse of vapour-filled bubbles. This process takes place at points inside the pump where the pressure falls below the vapour pressure of the pumped medium.
Downforce is a downwardly directed force acting on the pump's impeller/shaft unit during operation.
Dry running, also referred to as inadequate lubrication, occurs when there is air in the rotor chamber, meaning that rotating parts are not cooled and lubricated as they should be. Dry running leads very rapidly to destruction of the pump.
‘Lift’ refers to a condition whereby an upwardly directed force acts on the impeller/shaft unit of the pump during operation.
A drainage pump is primarily intended for pumping surface water and seepage to different locations, and for the pumping of groundwater.
The maximum sand content of the water may not exceed 50 g/m³.
While operating the pump, an uninterrupted minimum flow rate is required in order to sufficiently cool the pump and the motor.
In order to ensure adequate cooling and lubrication of the pump, there must be sufficient volume flow through the pump.