A Study on Grease Leakage from Rolling Bearings

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Naofumi Hiraoka


The leakage of grease from shielded rolling bearings is usually caused by grease being pushed out by ball or cage motion, centrifugal force, or grease flow due to high temperature. However, we have discovered another mechanism that causes significant leakage: slippage of the grease lump caused by adhesion forces to the shield plate and inner race which typically occurs in case of slippery grease on the surface.


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Research Article


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