The Fatigue Analysis And Upgrade Of A Transmission System Considering The Characteristic Of Load

Transport for bulk dry-mixed mortar is a new kind bulk truck. It is difficult to use software to simulate the load of this kind of new car's transmission system. there is no useful parameter performance about the load characteristic of air compressor and research method for the parameter performance. Once the transmission system is breakdown, it is difficult to diagnose the problem and fix it.In order to diagnose the problem of transmission system about some kind of transport for bulk dry-mixed mortar, which are the fracture of universal joint and yoke, the cracking of air compressor's out housing and the loosing of flange connection bolt, this thesis design a set of testing equipment which can test the torque, ranout and revolving speed of shaft, the acceleration of vibration of air compre ssor and the pressure of cargo tank.According to the result of data analysis, the install angel of transmission shaft is unduly large and too large torque while starting the transmission system with full load. The relationships between shaft torque and the revolving speed of air compressor has been found. An initial improvement project had been proposed.Based on the fluid-solid coupling simulation method, the cause of the load characteristic of air compressor has been researched and the relationship betw een the valve block opening size and the torque. A reasonable plan has been proposed based on the load characteristic of air compressor.The fatigue life calculation of universal joint and yoke was based on the testing torque data and the fracture of yoke and universal joint have been explained. The influence of air compressor 's load characteristic on the fatigue life of transmission system has been proved. Regarding the shaft fatigue life as a constraint, the topology method had been applied to redesign shape. The problem of fracture had been solved by selecting a reasonable working speed of air compressor and redesigning the shape and size of shaft yoke and universal joint. This paper provide a reference for fault diagnosis, optimization and upgrading of the new car's pressure transmission system.