ANALYSIS OF METRO WHEEL WEAR BASED ON FIELD MEASUREMENT AND NUMERICAL SIMULATION

The wear characteristics of wheels for one metro line were acquired through tracking measurement. The reason for the abnormal wear in wheel flanges was analyzed from the point of view of wheel/rail interaction. A dynamics model for the metro vehicles was developed and then used with the evaluation method of wheel wear based on wear work to research measures to mitigate wheel wear. The results of wheel wear measurement show that the magnitude of wheel flange wear is greater than that of wheel tread wear, and asymmetric wheel flange wear occurs on the same wheelset. The lack of lubrication and the asymmetrical distribution of sharp curved track are the main reason for excessive and asymmetric wear in the wheel flanges. The results of numerical simulation show that a proper decrease in the longitudinal stiffness of primary suspension can mitigate wheel wear. Lubricating wheel flanges and/or gauge corners of high rail can evidently reduce wheel flange wear and rail side wear. A decrease in coefficient of friction by 0.05 led to a reduction in wheel/rail wear of about 16.1%. Passenger capacity has also some influence on wheel/rail wear. Wheel/rail wear will increase by about 4.8% when the axle load increases by one ton. For the actual metro line investigated in this paper, it is proposed that the rail side of high rail of sharp curved track be lubricated in order to mitigate wheel flange wear and rail side wear. In addition, periodic reversing of the train can retard asymmetric wear in the wheel flanges.