Water Drop Detection Contained in Lubricant Oil for Submersible Pump Fault Diagnosis

In this paper, we propose a method to detect microscaled water drop contained in lubricant oil for a submersible pump fault diagnosis. The real-time deterioration detection of the submersible pump is quite important to guarantee working continuously during pumping water. However, it is rarely reported on proper real-time monitoring tool to predict the submersible pump fault. Because the submersible pump is always using in water, detection method to predict fault is limited. Moreover, vibration, solid housing and 24 hours continuous working of pump are also affected fault detection method selection. However, our detection method uses a simple optical measurement setup consisted of LEDs and photodiodes, by which real-time detection of submersible pump fault is realized. The most common damage of submersible pump is water inflow into oil room due to mechanical seal degradation. The oil room is filled up with lubricant oil to support motor axis rotation. We detect microscaled water drops flowed into oil room by using optical measurement setup and predict the submersible pump fault. We performed experiment to verify the method. As a result, we confirmed that the effectiveness of the proposed optical method for the detection of water drop contained in lubricant oil. Furthermore, we found that the photodiode output voltage changes according to power law with change of inflow water quantity.