The application of acoustic emission (AE) technique in detection and monitoring of bubble formation
and collapse in valves are presented in this review. The generation of AE signals and the basic compositions of
AE detection system are briefly explained. The applications of AE technique in valves are focused on condition
monitoring and detection bubble formation (bubble cavitation), and leakage of water through valves. All results
prove that the AE technique works well for detection and diagnosis of failures during valves
