Research On Grinding Pattern Optimization Of Abrasive Belt Under Torsion Of Contact Wheel

Rail grinding is recognized as an effective means of rail maintenance by domestic and foreign railway departments.It removes rail surface materials to eliminate rail damage and repair rail profile.As a new type of rail grinding technology,rail abrasive belt grinding technology has been applied to practical engineering applications due to its characteristics of elastic grinding,efficient grinding,and flexible grinding.With the improvement of people’s living standards,the pursuit of efficiency and the increasing awareness of safety and environmental protection,in order to improve the efficiency of rail abrasive belt grinding and reduce the risk of fire,this article focuses on the process of rail abrasive belt grinding,when the contact wheel is operated in different positions and postures The contact relationship between the rail and the rail is researched,and based on this,the algorithm for generating the process parameters of the rail abrasive belt grinding is developed.The main research contents involved in this article are as follows:Firstly,according to the rail grinding operation method,the position and posture of the contact wheel relative to the rail are defined.The removal process of the grinding material around the rail is based on the Hertz contact theory and the semi-hertz contact theory.The change rule of the projected length of the contact wheel longitudinal section is found to increase the usage rate of the abrasive belt after the contact wheel is twisted;the contact model between the contact wheel and the rail that involves curvature matching is established,and the contact wheel is established Material removal model when grinding in different poses.Secondly,according to the actual operation situation of rail abrasive belt grinding,the simulation calculation model of contact wheel and rail was established.Based on the finite element method,the theoretical model was verified and analyzed.At different deflection angles,torsion angles and grinding pressure,The distribution rule of the boundary of the contact area on the rail surface and the change trend of the magnitude of the contact stress show that the theoretical model has a good prediction accuracy,and at the same time provide a basis for the research on the parameters of the rail grinding process.Thirdly,The applicability of the theoretical contact model to different grinding objects was verified and analyzed by rail abrasive belt experiments.The results show that the theoretical contact model has certain rationality,and can be used to predict the width of the polishing belt for rails with irregular profiles.Finally,based on the above method,the material removal model of the contact wheel in different postures for rail grinding is considered.The impact of the arrangement of the contact wheel on the rail profile creation is considered.The particle swarm optimization algorithm generates a combination of process parameters for rail abrasive belt grinding that meets the grinding requirements,and the validity and scientificity of the generated process parameters are verified by using the rail grinding quality evaluation index.