The existing conditions of the selection of the permissible stress for the spring with 2 grade stiffness for freight cars are described.

With the engineering example of a V-shaped leg rigid frame arch bridge in the downtown of Luogang in Guangzhou, the force analysis of the bridge is introduced, focusing on calculation of the pile foundation spring rate and the key points for construction.

Based on test conditions with consideration of the nonlinear contact between spring leaves,an accurate finite element model for the fewer-piece leaf spring at both assembling and loading states is built,and the stress distribution and the spring rate of leaf spring,which are close to the real conditions,are obtained through finite element analysis with stress superposition.

This paper introduces the design principle and features of an automatic measuring and sorting system for spring rigidity based on 8031 single-chip microcomputer.

In this paper, step displacement, spring stiffness and time step are discussed through an (example).

Based on the model,an adjusting method for spring stiffness and the damping of shock absorber is put forward,which is then validated through the simulation tests on a SUV.

Experimental tests on friction and wear behavior of copper-impregnated metalized carbon sliding against stainless steel were carried out under the conditions of different spring stiffness,current intensity and sliding velocity on a pin-on-disc tester with electric current,and the friction coefficients,wear rates,and discharge intensity were tested.

Then the analysis and experimental study are made about three possible factors to affect the hysteresis of the actuator sys- tem, such as the magnetoconductivity of yoke、the stiffness of spring and the change rate of magnetic density, the ways in effect which minishe.

The influence of dynamic stability of stiffness of spring,damping,size of rod,temperature and exciting frequency etc are studied.