Contrastive Studies on Non-linearity Vibration Influences to Rigid-Flex Coupling System of Rolling Stock for Light Freight Rails

Some key techniques should be constituted focusing on the difficult problems in the rolling stock developments and operations for light freight rails, by which the commercial velocity can be raised respectively to 160/250 km/h when running crossover the three main lines of present normal-speed rails or the permissible ballast tracks of newly-built high-speed rails with the cargo distribution capacity promotion and the considerable profit expectation from medium/long-distance transportations. By applying the traction-rod inner design with both bogie cradle and mono traction-rod device, the rapid freight bogies have been evolved to bolsterless ones from bolster ones. To take the secondary rubber stacks instead of the airspring suspensions, \( K_{2} \gg K_{1} \), the simulation analyses of rigid-flex coupling vibrations indicate that the current technical condition is not sufficient, in which the non-linearity influences of bogies to carbody interface can be caused therefore, and the non-linearity effects of mono traction-rods can also be introduced to the longitudinal and lateral stiffness of secondary suspensions. As a result the carbody shaking phenomenon will be produced with the dramatic impacts to wheel-rail contact wear and light-weight carbody elastic vibrations. If changing to the use of Japanese airsprings, the optimal configuration of bolsterless bogie was formulated with actively sharing the technical achievements from the economical operations of rapid passenger rails, by which the rolling stock for light freight rails can be running on the extended routing crossover different-graded lines, so as to increase the availability of mobile equipments and to decrease the depreciate rate.