Research On Wheel Internal Damage And Tread Spalling

With the rapid development of high-speed railway passenger transport and heavy cargo transportation,the issues related to wheel-rail contact are directly related to the efficiency and safety of railway transportation.In recent years,a series of problems such as wheel-rail abrasion,peeling,and missing blocks have occurred at the railway site.How to solve these problems has become a focus of many long-term studies by experts and scholars.The research on the wheel-rail contact relationship has a very important significance for the safe operation of railway transportation and the reduction of application costs.This article first describes the background and status quo of railway development,then summarizes and summarizes the research status quo of wheel-rail contact related problems,and illustrates the research value of wheel-rail contact problems on the basis of this;Secondly,it describes rolling contact between wheels and rails.Theoretical and finite element methods and related theories lay a solid foundation for the in-depth analysis of wheel-rail contact problems.Third,they investigated the situation of wheel damage and maintenance at the railway site,and combed the data to prepare for finite element analysis.Finally,finite element method was used to establish the three-dimensional wheel-rail contact finite element model with different defects and damages.Then the calculation was performed.The internal cracks of different sizes and depths and the stress distribution around the impurities with different sizes and types were analyzed.There is already a problem of stress distribution in the case of contact between a wheel with a tread and a rail.The calculation and analysis results show that the crack geometry and the distance from the tread surface have a certain influence on the stress concentration generated by the crack tip during contact with the rails,and the crack is directly above the contact spot.When the crack length,depth,and angle increase,and the distance from the tread decreases,the stress value at the tip of the crack increases and the stress concentration becomes more severe;if there is an impurity such as Al2O3 in the material of the wheel,when the impurity is in the contact spot Immediately above,the closer the distance to the tread and the larger the volume,the higher the value of the modulus of elasticity of the impurities,the greater the stress around the impurities,and the more likely to be deformed or dropped off;when the internal crack tip or the periphery of the impurities is too stressful,or When other causes cause cracks to extend to the surface of the tread,resulting in peeling and falling of the tread surface,the peeling damage area is used as the contact area to contact with the rail,and the stress concentration area appears to peel around the damage circumference,and the smaller the tread peel damage area,The greater the depth,the greater the stress around the peeling damage,the analysis found that the peeling depth is more than the area to the stress.Big effect becomes more apparent.According to the research results of this paper,it has certain guiding significance for the inspection and replacement of wheels.When flaw detection technology is adopted,it is found that internal cracks or impurities of the wheel have developed to a certain extent,or the wheel surface has been peeled off and blocks have been repaired or replaced as soon as the warning of the tread surface is approached,so that the crack is completely eliminated before continuing to expand,and the railway is protected.Operational safety.