The Parameter Optimization And Failure Analysis Of The Metro Vehicle Suspension System

This article builds the dynamic simulation model of the metro vehicle system by using the multibody system dynamics software SIMPACK,which bases on current running of China ChengDu Metro type B bogie.and analysis the dynamic performance of the vehicle system model.and systematic analysis the effect of primary suspension parameters and secondary suspension parameters on the dynamic performance of metro vehicle systems.at last this paper analysis the dynamic performance of the non-normal running conditions.The main content of the work include:Firstly this article systematic expounds the characterists of the Metro vehicle system bogie and structural components.and then builds the system dynamic model of the metro vehicle by using the multibody system dynamics software SIMPACK, which calculates and analysis the parameters of the riding quality, curving safety and hunting stability in different speeds and curve contitions. What’s more,this paper optimizes the suspension parameters which influents the dynamic performance in different curve condition,including the longitudinal stiffness of the axle box for single Department of laminated rubber suspension parameters Kpx,the lateral stiffness of the axle box for single department of laminated rubber spring Kpy,secondary suspension parameters in the secondary suspension vertical damping Csz and secondary suspension lateral damping Csy and so on. What’s more,it analysis the dynamics performance parameters in the abnomal operating condition, including the condition of the secondary lateral absorber becomes ineffective,the condition of the airsprings which have no air,the conditional of having lateral wind when the vehicle is running,the condition when the tread eauivalent slope is0.35.The calculation and analysis the following conclusions:The metro vehicle model’s linear and nonlinear critical speed are greater than the maximum speed of the metro bogie requirement.the index of the ride comfort satisfies the requirement.the running wheel-rail lateral force on the conditions in each curve,the axle leateral force,derailment coefficient,wheel load reduction rate reached the relevant requirements of GB5599-85. By dynamics simulation as well as the time integration,it is recommended that the laminated rubber spring of the axle box for each department’s longitudinal stiffness Kpx is3.5MN.m-1.the laminated rubber spring of the axle box for each department’s lateral stiffness is2.5MN.-1.the secondary suspension vertical damper is20kN.s/m. the secondary suspension lateral damper is30kN.s/m.It is recommended that we should combine the manufacture technology、installation technology and material cost which choosing the suspension parameters. Non-normal running conditions considers the secondary lateral damper failure conditions,the airspring which have no air conditions,the conditions when tread equivalent slope is0.35,lateral wind running conditions. Analysis results of these abnormal conditions show that:The vehicle should slow down the running speed due to greater influence of secondary lateral damper to the The stationarity performance and the security performance which passing curve. The stationarity performance greatly reduces when the airspring which have no air conditions.The metro vehicle is recommend to reduce the running speed on positive line and have a speed less than lOkm/h on auxiliary lines;it is beneficial to run on small radius curve when tread equivalent slope is0.35.However,it is adverses to the huntingmotion critical speed on mail curve so as to slow down the running speed,and timely analysis to deal with the problem in order to avoid the traffic accident;The metro vhicle should reduce the speed on main curve when crosswind emerges.