Research On Stress Releasing Scheme Of Seamless Rail Based On Impact Tension Principle And Device Design

The emergence of seamless lines is a major revolution in the history of land transportation.It greatly reduces the amount of rail heads,extends the service life of lines and trains,and greatly reduces the maintenance cost of lines.At the same time,the trains are running.The process is more stable and comfortable.However,because the length of a single rail of a seamless line has increased a lot,but the width of the rail gap has not changed,this has led to a greater temperature stress on the seamless line than the traditional line.This keeps the proportion of rail stress relief work increasing in maintenance.At present,the stress relief work of the line[the end is stretched,and the rails are arranged in the middle to make the rails expand and contract freely in a stress-free state]The equipment used is relatively old,and its stress relief efficiency is low,the operation is complicated,and more human resources are required Such characteristics make them gradually unable to meet the demand of railway lines.The second-phase stress relief scheme is also not accurate enough for the equipment placement,resulting in insufficient stress relief.In this case,it is necessary to develop more efficient equipment and explore a more accurate release plan.Based on the working principle of the original stress-releasing equipment(human-powered pulley),this paper has developed a new stress-releasing equipment(automatic rail collision vehicle)that can meet the actual work needs.Based on the new equipment,a more efficient and accurate stress release is developed.The main tasks are as follows:1.Development of automatic rail cars.There are mainly motor selection and matching,timing belt design,balance mechanism design and quick link mechanism design.2.Based on the premise that the automatic collision car can have a relatively accurate impact force,ANSYS analysis is used to calculate the temperature rise of the rail at 35?,and the internal stress state is analyzed.Apply 5MPa prestress to the rail,analyze the tensile and impact methods to explore the effect of rail stress relief.Finally,the following conclusions are drawn:(1)Under the temperature load,the internal stress of the rail is evenly distributed and the stress value is equal everywhere;(2)When the tensile force is applied to the rail,under the load of the tensile force,the stress inside the rail will be quickly released,and then converted into tensile stress.Moreover,the stress value at each point after stretching is equal to the value of the tensile stress applied to the rail.(3)Three conclusions are drawn through the research on the stress release of the rail by the collision of the rail car collision rail.First,the rail cars eliminate the stress of the rails along the direction of the tensile wave transmission from the impact(the impact end to the fixed end);second,the tensile stress wave attenuation law inside the rail;third,the relationship between the impact speed of the rail crash and the stress relief distance.