Condition monitoring of low-speed bearings — a review

Abstract

Machines with operating speeds less than 600 rpm are classified as low-speed machinery. These machines are usually the most critical items in the production line, generally large and have high rotating inertias. Until recently, there has not been much interest in condition monitoring of these machines as they do not fail easily. However, if an expected failure does occur, the downtime and replacement costs can be enormous, which can lead to massive production loss. Unlike those medium- to high-speed machines, condition monitoring of low-speed machinery presents a challenge as traditional velocity and acceleration sensors are only sensitive to responses with high impact rates. The moving components of these machines that require condition monitoring are mainly bearings and gears. Due to the lack of interest until recently, there is limited literature on condition monitoring of low-speed machinery. In this review, the authors have attempted to gather together the innovative and advanced approaches on condition monitoring of low-speed machinery, with the main focus on rolling element bearing condition monitoring.