Condition monitoring of rotating machines using on-shaft vibration measurement

Condition monitoring of rotating machines enables early detection of faults and avoidance of unexpected machinery breakdowns. Vibration-based condition monitoring (VCM) is a well-known and well-accepted method for the health monitoring of rotating machines in industries. However the conventional VCM possesses some limitations in terms of using a number of vibration sensors at each bearing pedestal and sufficient experience to interpret the measured vibration data to identify fault(s), if any, present in the machine. Hence the on-shaft vibration (OSV) measurement has been proposed in this study using a tiny Micro Electro Mechanical Systems (MEMS) accelerometer with a wireless node for the data transmission to the computer. This approach is expected to reduce the number of sensors used currently and may also contain enriched vibration information about the shaft which may ease the fault diagnosis process. The proposed OSV measurement approach is applied to a small experimental rig and then experiments were conducted with a few simulated faults in the rig. Initial observations indicate that the OSV measurement gives better classification of different machine states compared to the on-bearing one. The experimental results are discussed in the paper.