Magnetic Bearings

[alansimpson]

I am looking for information on magnetic bearings, like where to get or applications in industry. I am doing R&D work on on rotating disc, around 100mm dia. and need ultra low friction bearings to run at speeds +1000 RPM.

Permanent or electric, active or passive bearings.

Any advice welcome

 

[tlee123]

How about air bearings? Friction is zero except for a tiny damping torque due to the shear of the air.

http://www.newwayairbearings.com

 

[Skogsgurra]

Agree. I would say that air bearings are perfect at those low speeds. A magnetic bearing often has more drag than an air bearing. That comes from eddy currents in the shaft. Air bearings start being tricky when you are in the 30 000 - 50 000 RPM region (with shaft diameters around 15 - 25 mm).

There are magnetic bearings that work with self-induced currents and they are even worse. The energy needed to keep the bearing centered is taken from the shaft rotation.

Is the disk vertical or horizontal? That may influence your choice.

Gunnar Englund

http://www.gke.org