A distinction is made according to the movement type of the displacer. The types are rotary and reciprocating positive displacement pumps.
Oscillating positive displacement pumps include
- Piston pump
- Diaphragm pump
The following constructions are counted among the rotating positive displacement pumps:
- Screw pump
- Progressing cavity pumps (eccentric screw pumps)
- Rotary lobe pump
- Gear pump
- Screw pump
- Peristaltic pump
In opposition to the centrifugal pumps the positive displacement pumps are suitable for a very high viscosity of the pumped fluid. Furthermore the reciprocating pumps can be suitable for metering and dosing applications.
They are used in particular for the transport of self-lubricating liquids and in the polymer sector.
