Bearing Diagnosis of Bogie Gear Box

Operation states of the gearbox bearings on an electrical multiple unit (EMU) bogie should be detected after being repaired. However, this is currently done using manual methods of visual inspection and listening to the sounds of the bearings to assess whether the bearings are working well or not. Therefore, it is difficult to discover faults in bearings and quantitatively diagnose faults. A test rig consisting of a motor and gearbox bearings used on a bogie was built to analyze the feasibility of fault diagnosis by means of determining the vibration signal characteristics of rolling bearings. Different bearing fault tests were performed to verify the accuracy of bearing fault diagnosis by fault characteristic frequency and to demonstrate the feasibility of assessing rolling bearing operation state through different vibration characteristics and different amplitudes of fault characteristic frequency. The analytical results of experiments on the running test rig showed that the proposed methods can be applied for the effective diagnosis of rolling bearing fault and assess rolling bearing operation state.