Vane pump as a pressure and suction pump for pneumatics and hydraulics

The vane pump (also known as a rotary vane pump) is a practical delivery device and pressure generator. Its design enables it to perform a wide variety of functions.

This delivery mechanism is used in hydraulics and pneumatics. It is suitable for medium operating pressures up to 300 bar.

How a vane pump works

The vane pump consists of the following components:

• Hollow cylinder
• Eccentrically arranged rotor
• Vanes
• Return springs
• Adjustment mechanism

The hollow cylinder serves as the stator and the housing. The rotor moves within it. This is either offset from the central axis of the stator or is movable. The rotor consists of a solid disk into which the vanes are inserted. A central compression spring presses the vanes against the inner wall of the stator.

Due to the eccentric position, the vanes move in and out of the rotor with every rotation. This constant change in volume creates the desired suction or pressure effect. Inlet and outlet lines guide the medium into and out of the vane pump.

The advantages of a vane pump

The vane pump is a practical and versatile device for generating pressure and vacuum. Its particular advantage is that it can be operated in both directions without any problems.

The more complex adjustable variants also offer particularly convenient functions. They allow for smooth pressure adjustment without changing the motor speed. Although the acquisition costs for the vane pump are higher, the motor control system can be selected more cost-effectively. Reversing the media flow is also particularly easy with the vane pump.

These are the disadvantages of the vane pump

The vane pump has a large number of moving parts. Above all, the vanes integrated into the rotor require sustainable lubrication. This applies particularly to pneumatic vacuum pumps. In hydraulic pumps, the fluid provides the lubrication. In pneumatic pumps, complex lubrication systems and a lubrication schedule are required, which must be conscientiously followed. As soon as the vanes in the pump jam, it loses its effect and no longer has any output.

Use of the vane pump

In a hydraulic context, the vane pump is used wherever constant motor operation is to be coupled with variable pump output. This makes the use of inexpensive three-phase motors possible. These electric motors are characterized by a constant power output at an equally constant speed.

Changes in speed are only possible with a delay and involve high electrotechnical effort. With the vane pump, only the position of the rotor needs to be shifted to bring about a change in the pump output.

In pneumatics, vane pumps are frequently used in laboratories. They offer quickly accessible pumping and suction power. Creating a vacuum is also particularly easy with this type of pump.