Gearbox fault diagnosis using acoustic data by cepstrum method

Fault diagnosis of rotary machines plays an essential role in reliability and safety of new industrial systems. Gears are considered as a vital part of the components of industrial machines, so that the defects of these components cause irreparable damages in industrial processes. Nowadays, many research workers conduct studies on the diagnosis of gear faults using data analysis. In this research, to acquire acoustic data from a sample gearbox, a system was fabricated and developed. Then, some common faults in the gearbox teeth were created artificially. In this research, cepstrum analysis method was used in order to detect the harmonics of gear mesh frequency and the family of sidebands created. In the primary investigation, the harmonics related to the gearbox shaft were identified with the cepstrum analysis method in the interval of 0 to 0.25 seconds. Then, in order to detect the faults of the gear, by analyzing in the interval of 0 to 0.0002 seconds, the faults related to the tooth were clearly visible and tracked. According to this research results by observing increase in amplitude of the first and fifth rahmonics, it is possible to detect faults such as broken and worn teeth of gears. The obtained results show the effectiveness of the presented method to diagnose the fault in the gearbox and prevent unexpected costs.