Establishment of the thermo-mechanical coupling model of axle box bearings with track irregularity excitation and analysis of its temperature characteristics

As an important component of the running gear of high-speed trains, axle box bearings can cause lubricating grease failure and damage to bearing components under continuous high-temperature operation, which will affect the normal operation of high-speed trains. Therefore, bearing temperature is one of the key parameters to be monitored in the online monitoring system for trains. Based on the thermal network method, this paper establishes a thermal network model for the axle box bearing, considering the radial thermal deformation of the double-row tapered roller bearing components caused by the oil film characteristics and the temperature variations of the lubricating grease. A thermo-mechanical coupling model for the grease-lubricated double-row tapered roller axle box bearing of high-speed trains with track irregularity excitation is established. The correctness of the model is verified using the test bench data, and the temperature of the bearing at different rotational speeds, loads, fault sizes, and ambient temperatures are investigated.