Simulation And Experimental Study On The Influence Factors Of Grinding Force Based On Rail Grinding Experiment

With the rapid development of economy and the people’s demand for the convenience of travel, the implementation of high-speed and heavy-haul strategy has greatly promoted the development of railway. However, with an increase in the load transfer between the rail and wheel, the rail diseases such as rail corrugation, crushing, damage and so on, are more and more serious and becoming an important factor restricting the development of railway. The rail grinding is the most economical and effective method of maintaining the rail surface. There is a complicated tribological behavior between the rail and grinding stone in the grinding process. Many factors affect the grinding force. Therefore, the study on the influencing factors on grinding force in the grinding process has a guiding significance for improving the grinding quality and optimizing the grinding parameters.The grinding is a complex material removal process and rail grinding can be seen as a special grinding process. Based on MATLAB image processing, the density and distribution of abrasive grains on the surface of grinding wheel were measured. The protrusion height of abrasive grain was analyzed by means of surface profile instrument. Furthermore, three-dimensional model of grinding wheel with different granularity was established using a CAD software and the software DEFORM-3D was used to simulate the grinding process. The rail grinding experiments were carried out using a rail grinding machines under different grinding wheel granularity, rotational speed and grinding pressure conditions. The experimental results were used to verify the validity and correctness of the model of grinding wheel and simulation results of grinding force.The main conclusions are as follows:(1) With an increase in the grinding pressure and grinding wheel granularity, the number of the active grains and undeformed chip thickness of single grain increase and then the grinding force increases. With the grinding rotational speed increasing, the grinding grains in the unit time increases and the undeformed chip thickness decreases, and then grinding force decreases.(2) The grinding process was simulated by means of the model of grinding wheel with different granularity under different grinding parameters conditions. There is a same change law between the simulation results and experimental results of grinding force. This verifies the validity of grinding wheel model.(3) Compared with the grinding force from three methods (integration method, finite element simulation and experiment), the value of the grinding force from simulation method is the biggest and the value of grinding force from integration method is the smallest. Furthermore, the relative error of grinding force between the simulation results and experimental results is smaller than that of between the integral results and experiment results.(4) According to the comparison of the grinding force from simulation results and experimental results, the correction coefficient was proposed based on a least square method. The results show that the modified simulation results is more consistent with experimental results and the relative error is less than 12%.