Wireless Temperature Sensor for Condition Monitoring of Bearings Operating Through Thick Metal Plates

Lokesh A. Gupta, Birck Nanotechnology Center, Purdue University
Dimitrios Peroulis, Birck Nanotechnology Center, Purdue University

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This research presents the first wireless temperature sensor for bearing condition monitoring, capable of operating through thick metal (greater than 18-mm thick) plates. The sensor is a combination of a ring-shaped permanent neodymium magnet and a Hall Effect sensor. Based on the temperature-induced change in the magnetic field, the sensor is able to detect bearing temperature remotely from a distance of 40.5 mm. Additionally, temperature-induced change in magnetic field is detected at a distance of 26 mm through two 9.5-mm-thick copper, stainless steel, and aluminum plates. Furthermore, the sensor concept is experimentally demonstrated by mounting it on a commercially-available bearing and performing dynamic tests at 1 500 rpm with 100-150 lb load. Maximum temperature readings for dynamic tests are in the order of 80 degrees C-90 degrees C, and are presently limited by the bearing test rig. However, the presented magnets are rated for operating up to 150 degrees C with an estimated lifetime of greater than 10 000 hours in operation.


Nanoscience and Nanotechnology