Macro Contact Pressure Modeling and Simulation for Rail Grinding with Abrasive Belt Based on Curvature Match

Abstract

：Rail grinding with abrasive belt essentially appears as the complex nonlinear contact interaction among contact wheel, abrasive belt and rail surface, the contact stresses calculation in which is the basis of modeling of material removal, grinding temperature and abrasive belt wear. However, the existing contact model for the concave contact wheel falls to consider the applicability of the Hertz theory and the effect of the "wheel" curvature matching. Based on the geometric matching between the radius curvature of concave wheel and that of rail profile, and also the influence of external contact pressure on rubber deformation of contact wheel, the macro contact of abrasive belt rail grinding is divided into three cases, including oval contact, double triangular contact and saddle contact. Then, this 3D contact problem is translated into 2D plane contact problem between the circular rigid body covered with thin elastic rubber layer and the rigid plane. Finally, the theoretical models for boundary curve and contact stress distribution are developed, and the finite element simulations are also implemented. Results show that almost identical contours of oval contact, double triangular contact and saddle contact can be obtained through the theoretical model and the simulation model, and the errors of main parameters are all within the allowable range of grinding condition for the rail grinding with abrasive belt, which verifies the validity of the proposed theoretical model. The proposed theoretical model has improved the existing model and laid a theoretical foundation for the modeling of grinding material removal for abrasive belt rail grinding using concave wheel.