A Simulation Investigation on the Influence of Bearing Outer Ring Defect on Dynamic Vibration Characteristics of the Axle-Box System

In this paper, a vehicle track coupling dynamic model including bearing outer ring defects is built, the time history of the axle-box vibration acceleration and the time history of the bearing roller-outer raceway contact load under the condition of random track irregularity on the Beijing-Tianjin line are obtained by simulation calculation. The results show that when the outer ring defect of the bearing occurs, the axle box will generate high-frequency vibration at the resonance peak in the vertical and lateral directions. When the defect on the bearing outer ring is in the small width of 1 mm, the roller only imposes one impact when passing through the defect area. However, when the width exceeds 3 mm, the large defect causes the roller to impose a double impact on the lateral direction of the axle box, due to changes in bearing clearance in the passing-through process. When the running speed of the train is about 250 km h-1, the width of bearing outer ring defects needs to be limited to within 1 mm, to minimize a series of problems such as structural fatigue caused by the increased bearing roller-outer raceway contact load caused by bearing outer ring defects. The bearing sub-structure model is imported into the vehicle-track coupling dynamic model including flexible wheelset to complete the bearing-vehicle-track coupled dynamic simulation model, as shown in Figure 4.image