What is a Positive Displacement Pump
A positive displacement pump (PD Pump) forces fluid to move by trapping a fixed amount of the fluid and forcing (displacing) that trapped volume into the discharge pipe.
The positive displacement pump provides an approximate constant flow at fixed speed, despite changes in the counter pressure.
Positive displacement pumps all pulsate, meaning that their volume flow within a cycle is not constant. The variation in flow and speed leads to pressure fluctuations due to resistance in the pipe system and in valves.
Applications for Positive Displacement Pumps
Positive Displacement pumps are used in industrial, food processing, water treatment, and petrochemical industries. Generally PD Pumps (such as peristaltic or diaphragm pumps) are also ideal for fragile substances such as cell cultures or shear sensitive polymers due to their gentle action.