Cavitation is a common fault in centrifugal pumps. The detection and diagnosis of the onset and severity of the cavitation provide the means of preventing the cavitation from causing harmful effects such as deterioration of the hydraulic performance, damage to pump components and the pollution by vibration and noise. This paper presents a new approach to monitoring cavitation based on the measurement of instantaneous angular speed (IAS) of the pump. IAS is measured using a cheap shaft encoder and processed using order spectrum analysis. It has been found that the normalised amplitude at the third order of the rotational speed can be used as a primary monitoring feature to detect the onset of the cavitation and to quantify the severity of the cavitation. A secondary detection feature is also defined in the high frequency range. This makes the detection results more reliable.

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Cavitation in a centrifugal pump causes deterioration of the hydraulic performance, damage to the pump components, high vibration and noise. To prevent cavitation and maintain pump performance, it is necessary to detect and diagnose the cavitation as early and accurately as possible. This paper presents non-destructive method to detect and diagnose cavitation in centrifugal pumps using statistical analysis of vibration signals. The vibration data was measured close to the discharge port and analysed in the time domain. It has been found that the probability density function (PDF) , Root mean square (RMS) and standard deviation (SD) values of structure vibration can be used successfully for detecting cavitation in centrifugal pump.

This paper is a part of condition monitoring of electrical submersible pumps (ESP). It assigned for reviewing and discussing faults or malfunctions of this kind of pumps. Therefore, it reviews all-important information related to this machine such as construction and operation. It focuses specifically on faults and details of these types of fault. Although there are slight differences between building submersible pumps in terms of the different technologies that different manufacturers use in making this type of pump, all kinds of these types of pumps are almost the same. In this context, pumps faults were reviewed based on major and common failures of this type of pumps.