What is Gerotor Pump | Construction, Working, Advantage and more

Table of Contents

Principle

Gerotor pump work on the principle of internal gear pump by using gear shaped rotor elements meshing internally.

Construction

Gerotor pump is a positive displacement pump. The name gerotor is derived from “generated rotor”. A gerotor unit have an inner and outer rotor. The inner rotor has n teeth, while the outer rotor has n+1 teeth.The axis of the inner rotor is offset from the axis of the outer rotor. These both rotors rotate on their respective axes.

It consists of following parts :

1) Outer ring : The outer ring is a casing in which gerotor pair is mounted.

2) Outer gerotor : Outer gerotor is idler and it has always one tooth more than inner gerotor.

3) Inner gerotor : The inner gerotor is the driver. The number of teeth of the outer and inner gerotor vary. The axis of inner gerotor is offset from the axis of the outer gerotor.

4) Suction and discharge port : The suction and discharge ports are provided to suck and deliver oil respectively.

Working

When inner gerotor rotates with the help of motor, it creates partial vaccum near the suction portwhen mesh with the outer gerotor. The oil enters through the suction port.

If the number of teeth for the inner and outer gerotor are four and five respectively, then while the inner gerotor makes one revolution, the outer one makes only 4/5 revolution.

Due to offset movement between inner and outer gerotor, the volume near the delivery port decreases and oil is forced out through delivery port.

The care should be taken as gerotor are to be manufactured with high precision otherwise internal leakage becomes excessive.

It can operate at the pressure of 125bar, maximum speed of 2000-3600 rpm with maximum discharge of 200 lit/min.

Applications

General mechanical and plant engineering
Shipbuilding and offshore industry
Paper, printing, and pulp industries
Heavy industry

Materials used for pump Construction

Externals (head, casing) – Cast iron
Internals (rotor, idler) – Steel
Bushing – Carbon graphite, bronze, and other materials as needed
Shaft Seal – Lip seals, component mechanical seals

Advantage of gerotor pump

Constant and even discharge

Operates well in either direction

Quiet operation

FAQ

What is the principle of gerotor pump?
It work on the principle of internal gear pump by using gear shaped rotor elements meshing internally.
What is the advantages of gerotor pump?
Constant and even discharge. Operates well in either direction. It has quiet operation.
What type of pump is Gerotor pump?
Gerotor pump is a positive displacement pump.
What is the pressure of gerotor pump?
It can operate at the pressure of 125bar, maximum speed of 2000-3600 rpm with maximum discharge of 200 lit/min.
Are gerotor pumps self priming?
It’s depend on pump manufacturer. Some gerotor pump like SKF product series 143 are self-priming, positive-displacement pumps with fixed displacement and high efficiency.
What is the application of gerotor pump?
It is suitable for General mechanical and plant engineering, heavy industries, etc.

If you want video of this Pump then click below link
how Gerotor pump work?