The Vibration Property Analysis And Test Research On The Shaft

In this article,the vibration characteristic of transmission shafts which uesd in modern industry is investigated,also the technology of how to improve their fatigue property is analysed. Thinking about the high working speed and large working loads, we use finite element method to calculate the stiffness, natural frequency and critical speed of different profile thickness of the transmission shafts with diaphragm coupling. Then we get the stress distribution of different profile thickness diaphragm couplings in working loads and the optimization design method about the profile thickness of diaphragm coupling.According to the optimization design method we make specimens and perform the diaphragm coupling stress test and compare with the finite element calculate results,in order to confirm the preciseness of the finite element calculating process. The high cycles fatigue test is also performed to validate their fatigue property. The result of high cycles fatigue test of the first specimen was not good. Because the diaphragm coupling is premature failure,and couldn’t meet the design requirement of fatigue strength. By means of analysis we find the premature failure of diaphragm coupling had nothing to do with the profile thickness of diaphragm coupling, but the material grain size and surface quality. On the basis of the first specimen, we improve the material grain size and surface quality of the second and third one, which pass the high cycles fatigue tests and prove that their diaphragm couplings met the design requirement. According to the three times of high cycles fatigue tests of the transmission shafts, we find out the influencing factor of fatigue property of diaphragm coupling and the method to improve their fatigue strength.By the research mentioned above, we make clear the vibration characteristic of the high speed rotor, the optimal design method and the influencing factor of fatigue property of diaphragm coupling, validate the veracity of design software of dynamics, and provid theories for the diaphragm coupling design of transmission shaft in the future.