Research of the on-line system for detecting metal particles in oil

Wear is one important type of the common mechanical faults. The number and size information of wear metal particles in lubricating oil can reflect the wear fault state of mechanical equipment. Electromagnetic particle information detection is one important method of particle detection. It has the advantages of simple structure, fast response, small influence of external interference such as vibration and oil bubbles, and so on. In this paper, aiming at the difficulties of particle electromagnetic detection, the mathematical model of exciting magnetic field and induction electromotive force was analyzed. The structure of differential screw electromagnetic sensor was designed. The direct digital frequency synthesis method was used to generate the excitation signal. Based on STM32F103 and MK60DN512 DSP chips, the signal detection hardware system was designed. The information analysis software system was designed based on QT C++ language. The developed system can detect the minimum number of 180 mesh wear metal particles, and it can be the research condition for the analysis of mechanical equipment wear state, fault diagnosis and early fault warning.