Reliability Study On The Under Cross-Braced Bogie Of Freight Car

In this paper, the development history of frame-brace bogie in foreign country is reviewed first; then the research achievement of bottom frame-brace bogie applied on the speed-up freight wagon and the primal existing problem and difficulty on safe and reliability are analyzed. Based on these, the philosophy, approach, main content and the object to achieve for study on reliability of frame-brace bogie are defined.By cooperation among manufacturer, college and research institute, utilizing the basic theory of reliability, the combined approach of emulation calculation analysis and test verification are applied to carry the structure analysis, parameter optimization and test investigation systemically for the safe reliability on the key parts and location of cross-anchor unit, double-acting elastic side bearer and damping device, which influence the operating performance of wagon. The design, trail manufacture and verification of cross-anchor unit with improved structure but without welding in the middle are completed; the optimization design, trail manufacture and test verification for the double-acting elastic side bearer without wear structure on end and high polymer composite material damping device with combined wedge are completed. The fatigue reliability and service life of cross-anchor unit are enhanced greatly. By thus, the stability of performance parameter and the full function of damping device are assured.With these achievements, the service life of cross-anchor is extended longer than two shop repair periods; the cross-anchor can be free of inspection within one shop repair period; the elastic side bearer structure and performance parameter match meet the performance requirement of stable operation for 120 km/h speed-up wagon; the fatigue life of elastic side bearer body reaches more than 6 years; these make the damping device of bogie stable and make the friction of friction wear of damping device within one repair period not exceeding the condom limit.By applying achievements on wagon, the safe reliability of bottom frame-brace bogie for newly-manufactured wagon and speed-up modified wagon are greatly enhanced meeting the operation requirement for railway freight wagon in China.