A positive displacement pump makes a fluid move by trapping a fixed amount and displacing that trapped volume into the discharge pipe. Some positive displacement pumps use an expanding cavity on the suction side and a decreasing cavity on the discharge side.
The benefit of a positive displacement pump is that the volume of liquid is constant for each operational cycle.
There are many benefits of positive displacement pumps for varying applications.
- Positive Displacement pumps are sometimes called constant-volume pumps because they maintain a constant speed and flow. Even if the system pressure varies, the flow remains constant.
- Positive Displacement pumps can handle a variety of fluid types: high, low and variable viscosity; shear sensitive fluids; solids; and liquids with a high percentage of air or gas entrainment.
- Their capacity is not affected by the operation pressure.
- They can be more efficient than centrifugal pumps when handling viscous fluids.
- Positive Displacement pumps are able to self-prime.
- They can be designed as a sealless pump.
Positive displacement pumps have a wide variety of applications within industrial processing markets such as:
- chemical processing
- bulk transfer