웨이블릿변환이 접목된 포락처리를 이용한 저속 회전하는 구름요소베어링 결함 진단
Low Speed Rolling Bearing Fault Detection Using AE Signal Analyzed By Envelop Analysis Added DWT
0
조회
0
다운로드
2
인용
0
참고문헌
키워드
초록
Acoustic Emission (AE) technique is a non-destructive testing method and widely used for the early detection of faults in rotating machines in these days, because the sensitivity of AE transducers is higher than normal accelerometers. So it can detect low energy vibration signals. The faults in the rotating machines are generally occurred at bearings and gearboxes which are the principal parts of the machines. It was studied to detect the bearing faults by envelop analysis in several decade years. And the researches showed that AE had a possibility of the application in condition monitoring system(CMS) using the envelope analysis for the rolling bearing. And peak ratio (PR) was developed for expression of the bearing condition in condition monitoring system using AE. Noise level is needed to reduce to take exact PR value because the PR is calculated from total root mean square (RMS) and the harmonics peak levels of the defect frequencies of the bearing. Therefore, in this paper, the discrete wavelet transform (DWT) was added in the envelope analysis to reduce the noise level in the AE signals. And then, the PR was calculated and compared with general envelope analysis result and the result of envelope analysis added the DWT. In the experiment result about inner fault of bearing, defect frequency was difficult to find about only envelop analysis. But it’s easy to find defect frequency after wavelet transform. Therefore, Envelop analysis added wavelet transform was useful method for early detection of default in signal process.
Abstract
Acoustic Emission (AE) technique is a non-destructive testing method and widely used for the early detection of faults in rotating machines in these days, because the sensitivity of AE transducers is higher than normal accelerometers. So it can detect low energy vibration signals. The faults in the rotating machines are generally occurred at bearings and gearboxes which are the principal parts of the machines. It was studied to detect the bearing faults by envelop analysis in several decade years. And the researches showed that AE had a possibility of the application in condition monitoring system(CMS) using the envelope analysis for the rolling bearing. And peak ratio (PR) was developed for expression of the bearing condition in condition monitoring system using AE. Noise level is needed to reduce to take exact PR value because the PR is calculated from total root mean square (RMS) and the harmonics peak levels of the defect frequencies of the bearing. Therefore, in this paper, the discrete wavelet transform (DWT) was added in the envelope analysis to reduce the noise level in the AE signals. And then, the PR was calculated and compared with general envelope analysis result and the result of envelope analysis added the DWT. In the experiment result about inner fault of bearing, defect frequency was difficult to find about only envelop analysis. But it’s easy to find defect frequency after wavelet transform. Therefore, Envelop analysis added wavelet transform was useful method for early detection of default in signal process.
참고문헌 (7)
- KIM, Y. H., "Experimental study on incipient fault detection of low speed rolling element bearings: time domain statistical parament", 12th Asia-Pacific Vivbration Conference (APVC2007) (2007), Hokkaido University
- Kim, Y. H., "A comparative study on the application of acoustic emission technique and acceleration measurements for low speed condition monitoring", Proceedings of the 12th Asia-Pacific Vibration Conference (2007)
- S. A. Mclnerny, "Basic vibration signal processing for bearing fault detection", IEEE Trans, Education, 46, pp.149~165 (2003)
- 양보석, "기계설비의 진동상태 감시 및 진단", pp.328~338 (2006), 인터비젼
- Kim, H. J., "The comparison of AE and Acceleration tranducer for the early detection on the low-speed bearing", Transactions of the Korean Society for Noise and Vibration Engineering Annual Spring Conference, pp.324~328 (2007)
- Jung, H. E., "The application of AE transducer for the bearing condition monitoring of low-speed machine", Transactions of the Korean Society for Noise and Vibration Engineering Annual Spring Conference, pp.319~323 (2007)
- Math work, "Signal processing tollbox user's guide" (1999), Math Work, Inc.