Magnetic radial bearings are used to in lieu of rolling element or fluid film journal bearings in some high performance turbomachinery applications. Specific applications include pumps for hazardous/caustic fluids, precision machining spindles, energy storage flywheels, and high reliability pumps and compressors.

Magnetic radial bearings yield several advantages. Since there is no mechanical contact in magnetic bearings, mechanical friction losses are eliminated. In addition, reliability can be increased because there is no mechanical wear. Besides the obvious benefits of eliminating friction, magnetic bearings also allow some perhaps less obvious improvements in performance.

Magnetic radial bearings are generally open-loop unstable, which means that active electronic feedback is required for the bearings to operate stably. However, the requirement of feedback control actually brings great flexibility into the dynamic response of the bearings.

By changing controller gains or strategies, the bearings can be made to have virtually any desired closed-loop characteristics. For example, flywheel bearings are extremely compliant, so that the flywheel can spin about its inertial axis--the bearings serve only to correct large, low-frequency displacements.

Conversely, magnetic bearings in machining spindles must be extremely stiff and have a very broad bandwidth so that tool position is accurately controlled. In each case, the dynamic response is a result of the controller used to stabilize the bearing, rather than a consequence of the bearing's physical design.

Radial Bearings :
Deep Groove Ball Bearings | Self Aligning Ball Bearings | Angular Contact Ball Bearings | Cylindrical Roller Bearings | Needle Roller Bearings | Spherical Roller Bearings | Taper Roller Bearings