Radial inductive debris detection sensor and performance analysis

Mechanical systems are prone to wear which can cause catastrophic failure if not detected and corrected in a timely manner. Hence, debris detection (type and concentration) is important for fault diagnosis and life prediction of hydraulic systems. The paper presents a new inductive method for debris detection based on a radial magnetic field. The sensitivity and precision of the instrument can be controlled by an independent parameter, resulting in higher sensitivity and precision. The paper provides a sensor structure and its mathematic model and discusses the features of the method. Finally, it is experimentally verified that the sensor can effectively detect 20 µm thick ferromagnetic debris (sphere equivalent diameter 290 µm) in a 20 mm diameter pipe. Simulation and experiment indicate that the new method has a distinct advantage relative to the traditional method.