Elektrische Automatisierungs- und Antriebstechnik
EAAT GmbH Chemnitz

Magnetic bearings from EAAT

The EAAT team has been setting new standards in the development and construction of magnetic bearings for more than 25 years. We use our experience to develop and manufacture magnetic bearings in a wide variety of designs and for different industries - always precisely tailored to the needs of our customers.

EAAT engineers will be happy to develop a magnetic bearing for you that is precisely tailored to your application.

Download Flyer

Advantages of magnetic bearings from EAAT

A magnetic bearing works without contact and is therefore wear-free. Lubricants do not have to be used, and maintenance requirements are low. Due to their hermetic encapsulation, they are ideally suited for vacuum applications or use in clean rooms.

Magnetic bearings enable direct process monitoring and the setting of position parameters via the control electronics during operation. Vibrations and imbalances can be actively dampened with magnetic bearings from EAAT.

 

A magnetic bearing - what is it?

A magnetic bearing enables bearing without material contact by using magnetic forces. Basically, active and passive magnetic bearings can be distinguished from one another.

Active magnetic bearings

active magnetic bearing

Active magnetic bearings generate their bearing force through regulated electromagnets that are arranged around the shaft. The position of the shaft is recorded with the help of position sensors. The differences between the setpoint and actual values of the position are evaluated by a digital control electronic and compensated with the aid of the power electronics. For this purpose, the electromagnets in the active magnetic bearing are controlled in such a way that the shaft remains in the desired position or takes this position. A continuous change of the setpoint is possible - e.g. if the shaft is to be moved on a revolving path.

Active magnetic bearings are dependent on a constant power supply and are therefore usually equipped with a mechanical safety bearing that provides protection in the event of a power failure.

Passive magnetic bearings

Passive magnetic bearings

The functionality of passive magnetic bearings is based on the forces of permanent magnets. Depending on the force acting on the shaft, there is a displacement from the central position, which remains as long as this force is active. For this reason, passive bearings are used when a force-related position deviation can be permitted.

Often, passive magnetic bearings are combined with conventional bearings or an active magnetic bearing. Contactless bearing in the radial and axial direction using only passive bearings is not possible. However, passive magnetic bearings are cheaper and do not depend on a functioning power supply.

 

Application areas

Thanks to their advantages, magnetic bearings are a powerful alternative to conventional bearing principles. Typical applications are e.g. compressors, vacuum applications, tool spindles and textile machines.

Realized products

Speed [rpm] Radial bearing force [N] Axial bearing force [N] Shaft mass [kg] datasheets
High speed motor 140.000 40 200 1,2 english
Rotating bending test bench - 8.000 - 2 x 85 (divided)
Turbine demonstrator 5.600 25.000 50.000 2.500
Safety bearing test bench 6.800 16.000 20.000 1.600
Flywheel energy storage 45.000 30 (passive) 300 8
Tubular centrifuge 75.000 145 200 9,3