Dynamic Modeling And Simulation Analysis Of Axle Box Bearing Of High-speed Train Considering Outer Ring Raceway Damage

The axle box bearing is one of the key components in the operation of high-speed trains,which is subject to complex and severe working conditions,and once the bearing fails,it will seriously affect the safe operation of trains and is very likely to cause traffic accidents.At present,the research around rolling bearing mainly focuses on how to diagnose the failure,but the research on the mechanism of bearing failure and the movement law between internal parts is still very insufficient.The thesis focuses on the influence of different damage positions of outer ring raceway on the internal dynamic behavior of the bearing,the main research contents include.(1)The mechanical analysis of the bearing is carried out based on Hertz contact theory and elastohydrodynamic lubrication theory,and the contact load between the roller and raceway is obtained by the "slicing method";The dynamic model of axle box bearing is established by multi-body dynamics simulation software ADAMS.model.The experiments on the dynamics of axle box bearings of high-speed trains were carried out,and the vibration acceleration on the outer side of the axlebox was measured,and the theoretical and simulated values of the component speed and the simulation results of the characteristic frequency of the failure were compared with the experimental results respectively to verify the validity of the proposed model.(2)The influence of the outer ring raceway damage location on the radial motion trajectory,mass center fluctuation amount and contact force between the internal components of the bearing was studied.It was found that: In terms of radial trajectory,when the outer ring damage position is located in the bearing area,the radial trajectory of the cage is relatively chaotic,while the trajectory in the non-bearing area has an obvious periodicity;In terms of centroid volatility,the outer ring damage position on the bearing internal components mass fluctuation amount of influence,of which the impact characteristics of the 12 o’clock position is the most obvious;In terms of contact force,between the roller and the inner and outer ring raceway contact force by the outer ring damage position,the damage in the 6 o’clock position,the outer ring raceway wear degree is greater.(3)The influence of speed and radial force changes on the dynamic performance of the bearing when the outer ring raceway is faulty was studied.It is found that: In terms of the influence of rotational speed,outer ring damage position in the bearing area has less influence on the roller slip rate,roller slip rate and rotational speed is positively correlated,too much slip rate will aggravate the uneven wear of the raceway surface;In terms of the influence of radial force,the smoothness of cage operation is affected by the outer ring damage position and radial force,the damage position in the non-bearing area when the cage operation is relatively smooth,the greater the radial force,the cage operation The greater the radial force,the more unstable the cage operation,moderate increase in radial force can reduce roller slippage.