Effect of periodic wheel tread reprofiling on wheel gauge evolution in the wheelsets of tread-braked coaches: Finite element modeling and field observations

Abstract

Field statistics of the wheelsets of gauge-widened coaches in the Indian Railways show higher tendency for excessive wheel gauge widening for lower diameter wheelsets. Additionally, the axial flange deflection in gauge-widened wheelsets increases nearly linearly with the radial distance. In this work, a finite element model is developed to investigate the reasons behind these field observations. The model considers heat generation during braking, heat loss to rail, brake blocks, ambient air, residual stresses generated during wheel manufacturing, and material removal during wheel reprofiling. Wheel gauge evolution is studied for different braking histories, including those that span the entire life period of the wheel, i.e. as the wheel diameter reduces from its initial to minimum allowable size. Simulations show that higher wheel rim temperatures and lower wheel stiffness, for lower diameter wheels, result in higher wheel gauge widening for these wheelsets. Wheel gauge widening occurs primarily due to bending at the hub–disc interface; consequently, the axial flange deflection increases linearly with the radial distance.