Condition monitoring of internal leakage in modern water hydraulic cylinders using acoustic emission

This research aims to develop a sensitive method for condition monitoring of internal leakage in a modem water hydraulic cylinder by means of acoustic emission (AE). Modern water hydraulics, which uses tap water as a hydraulic fluid, has been given increasing attention in recent years due to its inherent advantages over oil hydraulics, e.g., no environmental pollution, reduced product contamination, no fire hazard, low operating cost, etc. However, in order to benefit from all these advantages, some problems remain to be addressed. One of the most common problems of water hydraulics is leakage because the viscosity of water is low as compared with that of hydraulic oil. So far, there is no suitable method for condition monitoring of internal leakage in water hydraulic components. In this thesis, the author developed a new AE-based method for condition monitoring of internal leakage in a water hydraulic cylinder.DOCTOR OF PHILOSOPHY (MAE