Thermal Stress Analysis of the Heavy-haul Freight Car's Wheel Web Plate under the Wheel Tread Braking

Abstract

As an effective and efficient solution to enhance the capacity of the freight car transportation,the increase of axle loads may lead the wheel enduring larger heat loads and suffering more severe damage.In order to offer valuable technical supports for the operation,especially braking working condition,it is necessary and meaningful to compare the thermal stress of the wheel web plates for different axle load freight cars and reveal how the changes of the axle load affect the distribution of the temperature and stress.Basing on the thermal elasto-plastic theory,a new idea is put forward,which firstly studys the residual stress generated by the heat treatment process,and then simulates the distribution of the temperature and thermal stress for the wheels with residual strain using the time history of the heat braking power calculated from the omnidistance working conditions of the Datong-Qinhuangdao railway as a theraml load.It has been proved the residual stress generated by the heat treatment process cannot be ignored and the web plates will bear greater thermal and residual stress along with the increase of axle loads,by means of comparing the ones of the 21 t,25 t and 30 t axle load wheel web plate.