Distribution Law and Measurement Evaluation of Friction Torque of Miniature Ball Bearings under Light Load and Low Speed

To address the significant errors in the SKF friction torque model under small loads, we proposed a modification through the introduction of an additional corrective load, and the modified model was verified using miniature deep groove ball bearings of models 693 and 695. The research results show that under light load and low speed conditions, the friction torque of miniature bearings follows a three-parameter Weibull distribution, which can effectively describe the discrete characteristics of the friction torque of miniature deep groove ball bearings; under low speed and light-load conditions, the frictional torque of the bearing is not sensitive to the rotational speed-changes in rotational speed have almost no effect on the magnitude of the frictional torque; the calculation results of the modified SKF model are highly consistent with the measured results and can be used to accurately evaluate the friction torque of miniature bearings under light load and low speed.