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Development of an Array of EMAT for a Long-Range Inspection of a Pipe Using a Torsional Guided Wave  

Cheong, Yong-Moo (Nuclear Materials Research Center, Korea Atomic Energy Research Institute)
Jung, Hyun-Kyu (Nuclear Materials Research Center, Korea Atomic Energy Research Institute)
Publication Information
Journal of the Korean Society for Nondestructive Testing / v.27, no.3, 2007 , pp. 239-245 More about this Journal
Abstract
A torsional guided wave mode in a tubular structure has many advantages in obtaining a higher sensitivity and lower attenuation for a defect, because it shows no dispersion characteristics and no radial displacement for a tubular structure. Many attempts have been made to excite and receive torsional guided waves by conventional piezoelectric transducers, but only a few examples are used during a practical field inspection. In this study, an array of electromagnetic acoustic transducers (EMATs) were for an excitation and reception of the torsional guided waves in a pipe was designed and fabricated. The signal patterns were analyzed based on various beam path length. The feasibility of detecting the defects was investigated through a series of experiments with artificial notches on a pipe.
Keywords
Guided Waves; Pipe Inspection; EMAT; Torsional Vibration Mode;
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Times Cited By KSCI : 1  (Citation Analysis)
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