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 mu m thick ferromagnetic debris (sphere equivalent diameter 290 mu m) in a 20 mm diameter pipe. Simulation and experiment indicate that the new method has a distinct advantage relative to the traditional method.