CONDITION MONITORING OF LOW SPEED （状态监测的低速度）.pdf

CONDITION MONITORING OF LOW SPEED BEARINGS: A COMPARATIVE STUDY OF THE ULTRASOUND TECHNIQUE VERSUS VIBRATION MEASUREMENTS Yong-Han Kim a, Andy C C Tan a, Joseph Mathew a and Bo-Suk Yang b a CRC for Integrated Engineering Asset Management, School of Engineering Systems, Queensland University of Technology, 2 George St, QLD4001, Australia . b School of Mechanical Engineering, Pukyong National University, San 100, Yongdang-dong Nam-gu, Busan, 608-739, South Korea. Abstract: Bearing failure is often attributed to be one of the major causes of breakdown in industrial rotating machines that operate at high and low speeds. This paper presents results of a comparative experimental study on the application of the ultrasound technique for condition monitoring of low speed rolling element bearings and conventional vibration measurements with seeded faults on inner-race defects. The effectiveness of the ultrasound technique is demonstrated through signal processing techniques; use of statistical parameters derived from the time domain, and enveloped spectra in the frequency domain. The results reveal that the ultrasound technique is more effective in detecting low speed bearings failure than that of the vibration measurement. Key Words: Condition Monitoring, Low Speed Machinery, Rolling Element Bearings, Ultrasound Technique, Vibration Measurements 1 INTRODUCTION Condition Monitoring (CM) is the process used to determine the operational state and health of a machine