| With the constant improvement of the national consumption level and the widespread adoption of Internet e-commerce in China,the number and types of small-volume,light-weight,and high-value-added goods have increased dramatically.At the same time,the market for goods transport safety,timeliness,and economy has put forward higher requirements.This has also brought new opportunity for the development of Chinese railway express freight transport.As the core component of the express freight vehicle system,bogie still has many problems that need to be resolved.In this context,this paper systematic research on the key problems of the tumbler and the tumber axle box positioning rubber boshing of a 160km/h express wagon bogie.Firstly,this paper briefly describes the development and technical characteristics of the express freight and the express wagon bogies at home and abroad,and summarizes the main technical characteristics and key parameters suitable for own express wagon bogies,taking into account actual track conditions and operating conditions in China.This paper analyzes the advantages and disadvantages of tumbler axle box positioning and the problems of the positioning rubber bushing among different types,and the structure of the top box spring type arm positioning and express wagon bogie is described.The FEA software ABAQUS was used to calculate and obtain the four-direction stiffness curve of the rubber bushing.The results showed that the maximum absolute error between the calculated stiffness and the actual required stiffness was within the allowable range of engineering application.The results show that the deflection stiffness and torsional stiffness are constant values,and the deflection angle and the torsional angle are in a linear relationship with the torsional moment.The link between radial stiffness and axial stiffness show certain nonlinearity,but the degree of nonlinearity is not large,which can be approximately replaced by linear.According to the principle of conservation of energy,the three-direction stiffness of the tumbler box spring and the four-direction stiffness of the rubber bushing are integrated into the three-direction equivalent stiffness of tumbler axle box.On this basis,two dynamic simulation models of the actual stiffness and equivalent stiffness of the axle box are established respectively,and the dynamic performance of the two models is compared and analyzed according to the evaluation indexes in GB/T5599-1985.The results show that the critical velocity of the two models in the condition of empty and heavy vehicles is relatively close,and the maximum operating speed of the design is far exceeding that of 160km/h,which can meet the requirements of linear operation stability.The maximum vibration acceleration and stability indicators and curves pass safety standards to meet the standards.Compared with the calculation results of the equivalent stiffness model and the actual stiffness model,the vibration acceleration and the stability index are lower.When passing the curve,the axle lateral force,the wheel-rail lateral force and the derailment coefficient are larger,and the wheel load reduction ratio and the overturning coefficient are lower.The analysis results show that there is a certain error in the equivalent model.In order to truly reflect the dynamic performance of the bogie,the actual stiffness model of the axle box should be optimized.Finally,the actual tumbler axle box stiffness dynamic model to study the tumbler axle box positioning rubber bushing radial stiffness and axial stiffness and under three different air to weight ratio conditions tumbler length to the influence of vehicle dynamic performance.According to the change trend of every dynamic index,it is concluded that the best value range of the radial stiffness is 10MN/m~15MN/m,the best value range of axial stiffness is 6MN/m~9MN/m,and the best value range of tumbler length is 400mm~500mm. |
PDF Full Text Request