Research On Performance Of Rubber Buffer For Urban Rail Vehicles

With the continuous increase of population and the acceleration of urbanization in China,traffic congestion has become an urgent problem to be solved in every city.Urban rail transit has gradually become the main artery of urban public transport because of its advantages such as speed,high-performance,environmental protection and energy-efficient.Buffer as the important energy absorbing component of railway vehicles,can mitigate the impact and vibration during the train operation.However,the development of buffer technology in China is relatively late,and manufacture methods need to be improved.Therefore,characteristics of the rubber buffer for urban rail vehicles are studied in this paper.And this research provides a certain reference value for the future development of the new rubber buffer.Firstly,this paper briefly describes the development and technical characteristics of the rolling stock buffer technology at home and abroad,and summarizes the research progress of influences of the buffer performance on vehicle impact.Then the structure,performance parameters and the working principle of the rubber buffer studied in this paper are introduced in detail.The longitudinal stiffness of the rubber buffer under static and dynamic conditions are calculated and fitted by ABAQUS finite element software.And the calculated results are compared with the stiffness curves of the EFG-3 buffer.The results show that the longitudinal stiffness curves have obvious nonlinearity,and stiffness characteristics of the rubber buffer can be predicted by using finite element method.On this basis,taking a domestic metro train as an example,a four-car model with multi-degree of freedom and a train model with single-degree of freedom are established by using SIMPACK dynamic software,and the fitted buffer stiffness curves are input into the models.This paper analyses and calculates vehicle impact conditions of the traction,braking and collision of the metro train running on the straight line.The calculation results show that the rubber buffer has good energy absorption characteristics under traction and braking conditions,and the acceleration of traction can meet the requirements of GB/T 7928-2003 standard and TB/T 2370-1993 standard.In addition,the acceleration of braking and the average jerk can meet the requirements of GB/T 7928-2003 standard and EN 13452-2005 standard.In the case of collision,the combination of the rubber buffer and large-capacity collapse pipe can meet the energy absorption requirements corresponding to different collision velocities,and the maximum longitudinal acceleration of the vehicle is lower than the limit set by EN 15227-2008 standard.Finally,influences of rubber buffer characteristics on the curve passing performance of the train under traction and braking conditions are studied in this paper.The results show that the coupler will deflect relative to the connected vehicle during the curve passing process,which results in the lateral load component of the coupler in the horizontal direction of the vehicle system.And under the same condition,the maximum coupler deflection angle and the maximum lateral force decrease with the increase of curve radius.In addition,under influences of the lateral component of the coupler force,the curve passing performance of the metro train is still good.Safty indexes such as the axle lateral force,the derailment coefficient and the wheel load reduction rate of each car can meet the requirements specified in GB/T 5599-1985 standard.