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Preventive Maintenance of Hydraulic Installations Based on Monitoring Cavitation-Induced Vibrations

This paper presents results of experimental investigations on the frequency domains of cavitation-induced vibrations at an orifice plate and at a butterfly valve. These are two components that are often encountered in hydraulic installations. Orifice plates are usually used for measuring the flow rate, but they can also be used for restricting the flow. Butterfly valves are normally used to quickly shut off the flow and, to some extent, for throttling the flow (i.e. for adjusting the flow rate). Under certain operating conditions, cavitation and the accompanying damage can occur both at orifice plates and at butterfly valves. The results presented in this paper suggest that cavitation caused both by butterfly valves and by orifice plates seems to be indicated by high frequency vibrations having local maxima at roughly 18 kHz. From a practical point of view, these results could be used for preventive maintenance in industrial hydraulic installations.