The friction performance of roller bearings serves as a critical performance indicator. Currently, friction torque is commonly utilised to evaluate the friction performance of roller bearings. The value of the friction torque is significantly influenced by the specific measurement conditions, e.g., the bearing size, applied load, etc. This work proposes a novel concept of equivalent friction coefficient for roller bearings, which is elaborately interpreted using a tapered roller bearing as a case study. A measurement method for determining the equivalent friction coefficient of roller bearings was developed according to the theorem of kinetic energy. A kinetic energy model of the measurement system, incorporating the centre shaft and bearing under measurement, was established. A measurement platform for the equivalent friction coefficient was constructed and utilised for a typical type of tapered roller bearing. The equivalent friction coefficients at different rotation speeds were determined utilising the platform. The investigation results possess significant theoretical and engineering value in enriching the evaluation methods for the friction performance of roller bearings.
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