Bearings in ultra-high-speed applications, like in grinding machines or mills, are often lubricated by oil-air systems. A continuous air stream supplies a small amount of oil to the bearing, either by external nozzles directed at the gap between the outer and inner rings or through small holes in the outer ring. However, this requires a constant supply of high-volume compressed air, demanding external compressors with continuous power consumption.
A feasible alternative to this is an air-less lubrication system that delivers oil strokes directly through the outer ring. The impact on the bearing efficiency and oil film formation was investigated, using different SKF bearing prototypes under varying oil supply rates, up to 50,000 rpm. The results demonstrate the potential to significantly reduce the total energy consumption without compromising precision, performance, durability, or reliability. The study demonstrates a viable path toward more efficient high-speed bearing systems.