The Testing Research & The Non-linearity Finite Element Analysis Of The Hoop Structure Air Spring

Air spring is one of the major part of vehicle suspension system. Due to its excellent flexibility, high-level adaptability, good vibrating absorption and isolation, Air spring can decrease the natural vibrating frequency of vehicles and have a good effect on the stationary and comfort of vehicles. Thus air spring system is widely used on auto and rolling stock industry. As the developing of air spring research, air spring system is applicated succeeded on other flieds such as aviation, marine, precision instruments, textiles and military-industry.The belted air spring is currently the biggest bidding project of Australia Railway. The total bidding amount is about 24 million RMB. It has a good market prospects. The developing of this project will take the lead in designing belted air spring with high load capacity in domestic, and will establish air spring prediction model so as to conduct the design and exploitation of this kind of air spring better.Presently the study of air spring system is mainly based on the theoretical analysis and test measurement. The FEA method is still in its exploring stage. In the theoretical analysis, the analytical method and graphical method can be used to calculate approximate solution on the simple air spring. But on a complicated air spring, the calculation is to cumbersome and will result in poor operability and low accuracy, which makes less guiding significance on its practical application.Structural analysis of air spring involves the material nonlinearity of air bag and auxiliary spring, geometric nonlinearity caused by large deformation and the contacting nonlinear between air bag with top pate and auxiliary spring. The calculations are very complicated and hart to get convergence.In this paper, the current widespread finite element software ABAQUS is used to establish the static finite element model of belted air spring for calculation. In order to simulate the rubber more accurately, the uniaxial tensile test, biaxial tensile test and plane shear test were carried out on the rubber used in this air spring. Then the constitutive model of the rubber is made based on the experimental data.Using the rebar material model provided by nonlinear finite element software ABAQUS to simulate the tie cord composite's geometric and physical non-linear analysis can get excellent results. Using the gas element tallied with hydrostatic condition in the ABAQUS to simulate the air in the air spring. There are many factors affect the performance of air spring for the complexity of air spring structure, material and contract condition. This paper analyzes and studies the air spring on its vertical and lateral performance by using FEA technique based on air spring additional volume, pressure, angle of tire, layer and spacing of tire cord, angle of top plate.The experiment research shows that the calculating method applicated in this paper is effective and can be analogically used to analyze the similar air spring system, which furthermore can provide certain theoretic basis for design and exploitation development of the new air spring.