STUDY ON RAIL GOAL PROFILE BY GRINDING

An optimization method is put forward for the design of a rail goal profile based on the normal gap of the wheel and rail. Such a grinding rail goal profile is obtained by grinding and can be widely applied to heavy haul railways to efficiently reduce the contact stress level of wheels/rails. The optimization scope of the rail head is determined based on the theory of three-dimensional elastic bodies rolling contact with non-Hertzian. In the scope, the minimum gap forms between the original wheel and the improved rail when the wheelset shifts transversely. To mitigate the damage of the wheels and rails served in heavy haul freight railways, the present method is utilized to optimize the profile of CHN60 rail. The theory of vehicle and track coupling dynamics and three-dimensional elastic bodies rolling contact with non-Hertzian are used to analyze the contact behavior of the wheel/rail before and after the rail profile optimization in a static and dynamic state. The results show that the optimized rail profile is in good conformal contact with LM wheel, which reduces wheel-rail contact stress significantly without sacrificing the dynamic performance, and the wear status of the right wheel-rail and the left one are close. Therefore, the wear and rolling contact fatigue of the wheels and the rails served in heavy haul railways can be decreased effectively by using the optimized rail.