Sensitivity Analysis of Online Oil Quality Monitoring for Early Detection of Water Ingress in Marine Propulsion Systems

Gearboxes are critical equipment in the vessel propulsion system. Lubrication contamination caused by water ingress or condensation is one of the major failure modes in marine gearboxes leading to accelerated aging of lubricant, resulting in accelerated wear of gearbox components such as bearing and gears. This article presents a systematic evaluation of moisture ingress sensitivity of three commercial online oil quality monitoring sensors. A laboratory setup consisting of an industrial multi-stage planetary gearbox is utilised for the experimental studies. Furthermore, the gearbox vibration signatures are analysed to investigate the sensitivity of vibration measurements to water ingress to determine the need for oil quality monitoring when considering this specific failure mode.