Centrifugal pumps are flow machines that use the principle of centrifugal force. They consist of two main parts, pump and motor. In most cases, these pumps use electric motors, e.g. asynchronous, permanent magnet or synchronous reluctance motors, which convert electrical energy into mechanical energy. The pump is set in motion with the mechanical energy. Due to the rapid rotation of the impeller, the pressure drops in the center and rises at the edge of the impeller. Centrifugal pumps, also known as centrifugal pumps, use the suction generated by the rotation of the impeller to transport liquids. The pump is available in various designs, which is why it can be used in many applications. A distinction is made here between axial, radial and semi-axial (diagonal) pumps. Axial pumps consist of rotors that are aligned parallel to the axis of the pump housing and generate a flow-parallel movement of the liquid. Axial pumps are suitable for liquids with a low density or viscosity.

Axial fan. © 2022 CasaFan GmbH – www.ventilator.de

In radial pumps, the rotors are aligned radially to the axis of the pump housing and generate a radial flow movement of the liquid.

Diagonal fan. Copyright: ebm-papst Mulfingen GmbH & Co. KG

These pumps also deliver good performance with liquids with a higher viscosity. Semi-axial pumps have rotors that are located between the other two types and thus generate a combination of axial and radial flow.

Centrifugal fan. © 2022 CasaFan GmbH – www.ventilator.de

They are suitable for a wide range of liquids with different densities and viscosities.

This is how the centrifugal pump works:

The higher pressure that prevails at the edge due to the higher speed has a similar effect to stirring a liquid in a glass. The higher pressure automatically creates a vacuum, which draws more liquid from the inlet.

How a centrifugal pump works. © 2023 Innovative Systems GmbH