Dynamic Behaviour of Railway Axle Box Bearing Raceway Excited by Wheel Polygonal Wear

Being the connection between the bogie frame and wheelset, axle box bearing directly withstands the high-frequency wheel-rail impact and vehicle load. The polygonal wear exacerbates wheel-rail impact, which may lead to a deterioration in the performance of the axle box bearing, even threatening even threatening the train’s safety. To investigate the dynamic behaviour of axle box bearings, a rigid-flexible coupled vehicle-track dynamics model is developed. This model considers the dynamic interactions between the bearings and the vehicle components, as well as numerous nonlinear factors such as bearing stiffness, gear meshing, track irregularity and wheel polygonal wear. Then, the flexible axle box, wheelset, and gear box sub-models are integrated into the vehicle dynamics model. Subsequently, the developed model is validated by the field-tested axle box accelerations. Based on this, dynamic behaviour of axle box bearing excited by wheel polygonal wear is analyzed and discussed. Results show that the vibration and contact force acting on the axle box bearing increase with the amplitude of polygonal wear. The influence of high-order wheel polygonal wear on bearing vibration and contact force is more significant. In specific, the vibration at the position of axle box bearing’s outer ring under the wheel polygonal wear is slightly higher in amplitude compared to the vibration of inner ring. The contact force between roller and outer raceway is greater than the contact force between roller and inner raceway. These conclusions can be potentially considered in the design and maintenance of axle box bearings for railway vehicles.