Online Detection System of Metal Wear Debris Based on Symmetrical Magnetic Excitation Balance Magnetic Field Model

The metal wear debris generated by wear during the operation of the mechanical equipment can reflect the fault status of the equipment, and the online monitoring of the metal wear debris in the oil can timely understand the operation information of the equipment. Aiming at the effective response of metal wear debris under symmetrical magnetic excitation, an online monitoring system for metal wear debris with dual-coil balanced magnetic excitation was developed. Based on the spatial magnetic field distribution of the current-carrying element, an analytical model of the magnetic field intensity distribution of a single-turn current-carrying ring is designed, and it is optimized as a single set of coils made of a current-carrying ring, and the coupling of the magnetic excitation of the symmetrical double coil is deduced. The magnetic field distribution model is simulated and analyzed by numerical method. The flow channel of the system is 8 mm. After the semi-physical simulation test with the wear debris speed of 3.03-5.25 m/s, the sensor can realize the detection of 100 μm ferromagnetic metal and 1000 μm non-ferromagnetic metal. The experiment verifies the correctness of the simulation model of the coupled magnetic field distribution. This research provides technical support for the detection of hydraulic oil contaminants, which is of great significance for preventing hydraulic system failures and extending the working life of hydraulic equipment.