Centre bearing rotation forces during curve transitions
Centre bearing forces and wear losses in three piece bogies have been simulated using VAMPIRE®. Bogie rotational resistance has been modelled at centre bearings and constant contact side bearers accounting for uneven loading during track transitions. The detailed model handles cylindrical centre bearings accounting for rim wall contact as well as the centre plate planar friction connections and uneven loading. The simulations have been performed for a range of curve radii assuming gauge face lubricated track. Wagons of moderate or high friction resistance to bogie rotation at centre bearings and side bearers have shown altered wheel wear, reducing maintenance cycle times in operations for rollingstock. In this paper, simulation studies have examined the effects of cant deficiency / excess and transition curvature on the wear performance of wagons and individual wheelsets, in particular the high wearing leading wheelsets. Wheel wear is shown to be altered due to changes in bogie rotation friction moments retained through the curve when cant deficiency of the curve is altered. The simulation results also show that transition curvature design can be used to reduce high wheel/rail wear in 3 piece bogies generated by high bogie rotation resistance. In the same way, transition curvature design can be used to alter the wheelset angle of attack during constant curving on 3 piece bogies.