Research On The Comprehensive Evaluation System Of The Blade Performance For Rail Milling

With the development of technology and the increasing of the speed and loading of the railways,and the rails are the basis for the increase of speed for trains,and the requirements of surface quality for rails are getting higher.Meanwhile,it has brought challenges and intensified the wear of railway transportation.The rail milling and grinding vehicle is a currently-developed rail repairing device.Milling is the first step in the milling and grinding,which can remove most of the damage,and it directly affect the machining efficiency and machining effect.The blade is a tool that directly acts on the rail material.The cutting performance of the blade will directly affect the machining effect of the milling and milling machine.However,the current cutter plate mainly uses the imported blade.The price of foreign blade is two and three times higher than the domestic blade.In order to reduce the cost,a comprehensive evaluation system for the performance of blade for rail milling is studied.Aiming at the requirements for the selection and evaluation of milling tools for milling and grinding vehicle,this paper evaluates the performance of milling tools by setting reasonable evaluation indexes and conducting the rail milling tests.As the above statements,this paper draws the following conclusions:1)Firstly,according to the characteristics of milling machining,the cutting characteristics of rail materials and the requirements of rail damage repair for rail milling vehicles,different blade performance evaluation indexes were determined.Secondly,based on the theory of fuzzy mathematics,a comprehensive evaluation model of blade performance based on rails was established,the weight of the blade evaluation index was determined by the fuzzy matter-element method,and a comprehensive evaluation model for the performance of the rail milling insert was established,and the rationality of the model were verified based on blade wear and cutting force tests.It is verified that the judgement method of blade performance is to be one-sidedness only by relying on the maximum degree of membership,and ignored other degrees of membership.2)For the blade evaluation index(blade durability,cutting force,surface roughness and dimensional accuracy),four different coated blades were used to mill the rail material,and the influence of different factors such as the blade coating material,the coating structure was analyzed,and the change of index for blade under different cutting parameters.The influence of different cutting parameters on the milling force was analyzed through the milling force measurement test,and integrated all the inspection indexes to determine the most suitable blade for machining rail materials.3)The reliability calculation model of blade life was established on the basis of Bootstrap method to evaluate the blade durability reliability,and the influence of coating materials and coating structure on reliability was analyzed.Based on the mean and variance obtained by the Bootstrap method,the safe life of four blades with a reliability of 99%is acquired.