Dynamic Performance Analysis Of 160km/h Express Wagon

In order to meet the higher speed of freight transportation,the research and development of express wagon is imperative.The dynamic performance of freight train determines the safety of transportation.The running speed of express wagon train is higher than that of traditional ordinary freight train,and its dynamic performance and dynamic characteristics will also change.Therefore,the analysis of the factors that affect the dynamic performance of the express wagon plays an important role in the research and development of the express wagon and its safe operation.Firstly,this paper introduces the development process of express freight transportation,and the development process and current situation of express wagon at home and abroad.Then,taking the bogie assembly shed car body of a certain type of fast freight car with the highest speed of 160km/h newly developed by a factory as the research object,according to the structure of bogie and car body,the simulation model of 160km/h express wagon is established by using software SIMPACK.Calculate the normal dynamic performance of express wagon,and the calculated indexes can meet the corresponding standards.Then,taking a single bogie as the research object,four different types of wheel diameter difference are set to make the wheel diameter difference change in the range of 1-10 mm,and calculate the dynamic performance change of express wagon.It is concluded that the four types of wheel diameter difference have an impact on the nonlinear critical speed of express wagon,but all of them can meet the stability requirements of express wagon;the vehicle lateral stability index corresponding to the four types of wheel diameter difference increases with the increase of wheel diameter difference,and the equivalent wheel diameter difference has a greater impact on the lateral stability,but the maximum value is lower than the limit value,and the wheel diameter difference has little effect on the vertical stability of express wagon;For the curve passing performance of express wagon,the equivalent wheel diameter difference in the same direction has a significant impact on the lateral force,derailment coefficient and wear index of express wagon.When the wheel diameter difference is 10 mm,the lateral force and derailment coefficient are close to the limit value,indicating that the wheel diameter difference of express wagon exceeding 10 mm will affect the driving safety,and the equivalent reverse wheel diameter difference has a greater impact on the wheel load reduction rate and the lateral force of the wheel axle,and the four kinds of wheel diameter difference will aggravate the wear between wheel and rail.Finally,the influence of wheelset mass on the dynamic performance of express wagon is analyzed.The calculation results show that the nonlinear critical speed of the express wagon decreases with the increase of the wheelset mass from 0.8 times to 1.2 times of the initial mass,which indicates that the proper reduction of the wheelset mass is conducive to the improvement of the stability of the express wagon;the wheelset mass has little influence on the straight-line running stability of the express wagon;the wheelset mass has little influence on the speed of the express wagon.The lateral force,vertical force and derailment coefficient of the wheel and rail have great influence on the wheel load reduction rate when the express wagon passes through the curve at high speed,while the influence on the wheel load reduction rate is small.At the same time,when the express wagon passes through the rail joint,the higher the high-frequency vertical impact force with the increase of the wheelset mass,the greater the wheel rail wear will be.Therefore,in the process of research and improvement of express wagon,the smaller wheelset mass is conducive to reduce the wheel rail dynamic effect and improve the driving safety performance.