The maximum speed at which a rolling bearing can operate is largely determined by its permissible operating temperature. The operating temperature of a bearing depends on the frictional heat generated by the bearing, any externally applied heat, and the amount of heat that can be transferred away from the bearing.
Super-precision bearings that generate low levels of friction are, therefore, best suited for high-speed applications due to their corresponding low operating temperatures. When compared to similarly-sized roller bearings, ball bearings have a lower load carrying capacity but their smaller rolling contact area enables them to operate at much higher speeds. However, hybrid bearings provide additional benefits for all bearing types. Diagram 1 compares the temperature rise in grease lubricated spindles for different bearing types. The curves for the bearings can be considered representative for the whole bearing series.
Guideline values for attainable speeds per bearing series, are provided in diagram 2 for oil-air lubrication and in diagram 3 for grease lubrication. Both diagrams are based on the speed factor A. For details about the bearing series, refer to the designation system of:
Generally, bearings with a lower cross-sectional height can attain higher speeds because of the smaller value for mean diameter dm.
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