Abstract: Aiming at the current status of bearing radial clearance detection, manual measuring methods have low detection efficiency and poor precision, using ultra-high precision laser sensor, a new type of bearing radial clearance automatic measuring device was developmented. Through the design of the test conditions, data acquisition and processing, the measurement uncertainty of the device was analyzed and compared with the ultra-high precision Mahr length measuring instrument. The results show that the automatic detection of the radial clearance of the bearing can be realized by the device，and satisfy the accuracy requirement of measurement.
Key words: bearing radial clearance; automatic measurement; testing uncertainty; comparative measurement