Condition monitoring of low-speed rotating machinery using stress waves - Part 2

The mechanical integrity of rotating biological contactors (RBCs) and their bearings are vital to maintaining uninterrupted operation. Part 1 of this work presented a study of the high-frequency stress wave (SW) technique as a means of monitoring low-speed RBCs (1 r/min). While the present authors were involved with the development of a monitoring system for RBCs, they also used the opportunity to assess the viability of the application of SWs to monitoring low-speed bearings having bore diameters ranging from 80 to 125 mm. It is concluded that the mechanism of SW generation was the relative movement between mating components experiencing a loss of mechanical integrity, e.g. the loss of tightening torque between the clamped components of RBCs.