Research On Rail Grinding Capacity And Grinding Pattern For Abrasive Belt Based On Non-uniform Grinding Layer

Rail grinding is an important tool in railway maintenance technology for repairing the wear and damage of rail surfaces.In grinding operations,each grinding tool are deflected at different angles to envelope the diseased rail profile.After multiple passes of grinding,the surface defects of the rails are eliminated and the cross sections of the rails are shaped.This fixed combination of different deflection angles and grinding power is called grinding pattern.Compared with the traditional rail grinding,belt grinding is elastic grinding,which is not easy to damage the rail surface,and the grinding efficiency is high.In recent years,domestic and foreign countries have begun to study the grinding technology of rail abrasive belts,but there is no research on belt grinding pattern,which restricts the use of abrasive belt grinding technology.Therefore,this article proposed to use the belt as the main grinding tool in the rail grinding.It includes establishing the evaluation model of belt grinding capacity when the belt is used on the non-uniform grinding layer of the rail surface,and obtaining the rule that the belt affects the rail profile,hereby research the automatic generation algorithm of grinding pattern for multi-abrasive belt grinding operation.The main contents of this thesis are as follows:According to the distribution characteristics and maintenance requirements of rail disease profile,the paper proposed a screening method to find the typical disease profile for operation range.After that,to determine the material removal amount on the diseased layer of the rail surface,the difference between the rail disease profile and the target contour was quantitatively characterized.And then,the non-uniform characteristics of material removal amount distributing along the rail lateral was obtained.Combined with the distribution law and the grinding angle,determine the total amount of material removed from the surface of the rails.Based on the contact theory,the contact stress distribution law of the belt with the rail surface under the effect of concave contact wheel was obtained.Then,according to the distribution law of the contact stress,this paper calculated the removal volume of a single abrasive grain and determined the number of abrasive particles that involved in cutting in the contact area.Then the grinding capacity evaluation model of the belt on the non-uniform material removal layer is established.Finally,the influence rule of the belt on the profile of the rail when it is grinding in different contact areas is obtained,and next the grinding capacity evaluation model of the belt was verified according to grinding experiments.According to the distribution rule of the material removal amount of the disease rail along the rails lateral direction and the evaluation model of the grinding ability of the belt on the rail non-uniform material removal layer,this paper research the automatic generation algorithm of the grinding pattern based on the 80 belt grinding equipment.And then grinding profile and error was prediction,while the reasonability of the automatic generation algorithm of the grinding pattern was analyzed through the grinding error.The selection of the grinding pattern in the multi-pass grinding will affect the working efficiency.In order to improve the working efficiency,the grinding pattern is optimized to determine the optimum grinding pattern of the grinding belt in the multi-pass grinding.Finally,this article developed an automatically generated software for rail belt grinding pattern,which can automatically generate matching belt grinding pattern according to the disease steel rail profile.This program provides technical support for engineering application of abrasive belt engineering technology.