Friction characteristics of Grease-Lubricated cylindrical roller thrust bearings (Part 2): characteristics at running time, bearing load (influence of flow property, oil viscosity)

摘要

The effects of worked penetration, flow properties, and base oil viscosity of grease on the characteristics of friction in cylindrical roller thrust bearings were experimentally examined and the following results were obtained. (1) Bearings packed with churning type grease showed a dependence of friction on rotational speed in the light load range; torque also varied approximately with the half power of load. Frictional torque and the basic trends in axle temperature were similar to those in bearings with channeling type grease. (2) Similarly, bearings with churning type grease of low worked penetration showed high frictional torque, the opposite of the effect observed in channeled type grease. (3) The observed level of frictional torque has a complex relationship to the extent of worked penetration and with flow properties of the lubricant, but once grease flows to the joint, the torque is dominated by the viscosity of the base oil. Therefore, the running smoothness and friction characteristics of the bearing show a rather strong dependence on the base oil.