Condition Monitoring and Detection of combined defects of electromotor and gearbox system in the frequency and Time-Frequency domains; Case study: rotary machines of Markazi Province Iron Ore Plant

In this study, the condition monitoring of the rotary machine was considered that led to detecting of combined defects including gear and electromotor bearing faults. Using Easy Viber vibration analyser and 3-axial CTC accelerometer sensor installed at 4 points, the bearing vibration time signals were extracted with a data sample rate of 8196 Hz and were compared ISO 10816-3. Then, using FFT, the signal resolution and clarity were improved by using appropriate filtering. Then, time-frequency domain transformations were used to identify more accurately the types of defect and their locations. STFT, wavelet transform and EMD by MATLAB were considered.