Fault diagnosis of reciprocating compressor valve using acoustic emission

The faults of a reciprocating compressor valve can be diagnosed using the acoustic emission. Four typical valve faults including the crack, rupture and deformation in the valve discs and leakage through the flow passage were investigated. The fault features were extracted by comparing the acoustic emission signals from the failed valves with those from the normal valves. The results show that the feature locations where the discharge valve opened and closed could easily be identified by the envelope waveform of acoustic emission signal, and they changed when the valve failed including the rupture and deformation in valve discs and leakage through the flow passage and changed with the variation of the discharge pressure. The extent to which the valve failed could be estimated by the deviation degree between the opening/closing locations and the standard ones. The leakage caused by these valve faults could also lead to the increase in the amplitude of the acoustic emission wave. However, the fault of crack in valve disc couldn't be identified by acoustic emission signal effectively.