Journal of the Korean Society for Nondestructive Testing (비파괴검사학회지)

The Korean Society for Nondestructive Testing (한국비파괴검사학회)
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A Study on the Behavior of Ultrasonic Guided Wave Mode in a Pipe Using Comb Transducer

Comb Transducer를 이용한 파이프 내 유도초음파 모드의 거동에 관한 연구

  • 박익근 (서울산업대학교 비파괴평가기술연구센터) ;
  • 김용권 (서울산업대학교 에너지 환경전문대학원) ;
  • 조윤호 (부산대학교 기계공학부) ;
  • 안연식 (한전 전력연구원) ;
  • 조용상 (한전 전력연구원)
  • Published : 2004.04.30
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Abstract

A preliminary study of the behavior of ultrasonic guided wave mode in a pipe using a comb transducer for maintenance inspection of power plant facilities has been verified experimentally. The mode identification has been carried out in a pipe using the time-frequency analysis methods such as the wavelet transform(WT) and the short time Fourier transform (STFT), compared with theoretically calculated group velocity dispersion curves for longitudinal and flexural modes. The results are in good agreement with analytical predictions and show the effectiveness of using the time-frequency analysis method to identify the individual modes. It was found out that the longitudinal mode(0,1) is less affected by mode conversion compared with the other modes. Therefore, L(0,1) is selected as an optimal mode for the evaluation of the surface defect in a pipe.

발전설비의 보수검사에 적용하기 위한 예비 연구로 comb transducer를 이용한 파이프 내에서의 유도초음파 모드의 거동을 실험적으로 검증하였다. 유도초음파의 모드식별은 STFT와 WT에 의한 시간-주파수해석을 통하여 최적의 모드를 선정하였다. 시간-주파수해석과 이론적 해석 방법인 분산 곡선을 비교한 결과 잘 일치함을 알 수 있었으며, pitch-catch법과 선단부로부터 반사된 신호를 모드 분석한 결과 L(0,1) 모드가 다른 모드에 비해 모드변환에 의한 영향이 적었다. 따라서 L(0,1)을 최적의 모드로 선정하고, 결함위치를 추정한 결과 유용함을 알 수 있었다.

Keywords

References

  1. I. K. Park, U. S. Park and H. M. Kim, 'Statistical Reliability Assessment of Ultrasonic Performance Demonstration - A Round Robin test Results - (part Ill),' KSNT/SC0031, pp. 214-219, (2003)
  2. S. J. Song, J. S. Park and H. J. Shin, 'Guided Wave Mode Selection and Flaw Detection for Long Range Inspection of Polyethylene Coated Steel Gas Pipes,' Journal of the Korean Society for Nondestructive Testing, Vol. 21, No.4, pp. 406-414, (2001)
  3. D. N. Alleyne and P. Cawley, 'Long Range Propagation of Lamb Waves in Chemical Plant Pipework,' Materials Evaluation, Vol. 52, No.7, pp. 504-508, (1997)
  4. Tatsuyuki Nagai, Masami Hyodo and Kenichi Takamura, 'Long Range Ultrasonic Technique for Inspection of Buried Pipelines,' Journal of the Japanese Society of Non-Destructive Inspection, Vol. 51, No. 10, pp. 622-627 (2002)
  5. Peter J. Mudge and Alan M. Lank, 'A Long Range Method of Detection of Corrosion under Insulation in process Pipework,' Journal of the Japanese Society of Non-Destructive Inspection, Vol. 46, No.4, pp. 314-319, (1997)
  6. H. J. Shin, Joseph L. Rose and S. J. Song, 'Inspection of Heat Exchanger Tubing Detects with Ultrasonic Guided Waves)' Journal of the Korean Society for Nondestructive Testing, Vol. 20, No.1, pp. 1-9, (2000)
  7. Joseph L. Rose and Dale Jiao, 'Ultrasonic Guided wave NDE for Piping,' Materials Evaluation, Vol. 51, No.5, pp. 1310-1313, (1996)
  8. S. P. Pelts, D. Jiao, and J. J. Rose, 'A Comb Transducer for Guided Wave Generation and Mode Selection,' IEEE Ultrasonics Symposium, pp. 857-860, (1996)
  9. S. Pelts, J. L. Rose and Y. Cho, 'A Comb Transducer for Guided Wave Mode Control,' Review of Progress in Quantitative NDE, Vol. 18, pp. 1029-1036, (1998)
  10. D. N. Alleyne and P. Cawley, 'Optimization of Lamb wave inspection Techniques,' NDT & E International, VoL 25, pp. 11-22, (1992)
  11. Hegeon Kwun, Sang-Young Kim and Glenn M. Light, 'Long-Range Guided Wave Inspection of Structures Using the Magnetostrictive Sensor,' Journal of the Korean Society for Non-Destructive testing, Vol. 21, No. 4, pp. 383-390, (2001)
  12. H. J. Shin and S. J. Song 'Time-localized frequency analysis of ultrasonic guided waves for nondestructive,' Review of Progress in Quantitative Nondestructive Evaluation, D. O. Thompson and D. E. Chimenti eds, Plenum Press, New York, Vol. 19, pp. 709-716, (1999)
  13. W. H. Prosser, Michael D. Seale and Barry T. Smith, 'Time frequency domain analysis of the dispersion of Lamb modes,' Journal of the Acoustical Society of America 105 (5), pp. 2699-2676, (1999)
  14. A. Abbate, J. Frankel and P. Das, 'Wavelet transform signal processing for dispersion analysis of ultrasonic signals,' Proceeding of IEEE Ultrasonics Symposium, (1995)
  15. Zongqi Sun, Yiwei mao, Wenhua Jiang and De Zhang, 'Investigation of Interaction of Lamb Waves and Circumferential Notch in pipe by means of Wavelet Transform,' 2000 IEEE Ultrasonics Symposium, pp. 827-830, (2000)
  16. D. N. Alleyne and P. Cawley, 'A two-dimensional Fourier Transform method for the measurement of propagating multimode SignaIs,' Journal of the Acoustical society of America, 89(3), pp. 1159-1168, (1991)
  17. Takahiro Hayashi and Koichiro Kawashima, 'Mode Extraction from Multi-modes of Lamb Waves,' Review of Progress in Quantitative Nondestructive Evaluation, D. O. Thompson and D. E. Chimenti eds, Plenum Press, New York, Vol. 21, pp. 219-224, (2002)