Shear-horizontal wave-based pipe damage inspection by arrays of segmented magnetostrictive patches

• Published in: IEEE transactions on ultrasonics, ferroelectrics, and frequency control Vol. 58; no. 12; pp. 2689 - 2698
• Main Authors: Kim, Hoe Woong, Kwon, Young Eui, Cho, Seung Hyun, Kim, Yoon Young
• Format: Journal Article
• Language: English
• Published: New York, NY IEEE 01.12.2011; Institute of Electrical and Electronics Engineers; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Acoustics; Antenna radiation patterns; Applied sciences; Arrays; Circumferences; Coils; Cracks; Damage; Equipment Design; Equipment Failure Analysis - instrumentation; Equipment Failure Analysis - methods; Exact sciences and technology; Flaw detection; Fundamental areas of phenomenology (including applications); Industrial metrology. Testing; Magnetic Fields; Magnetic resonance imaging; Magnetostriction; Mechanical engineering. Machine design; Non-destructive testing: methods and equipments; Physics; Pipe; Rheology - instrumentation; Scattering, Radiation; Segments; Shear Strength; Surface waves; Transducers; Ultrasonics, quantum acoustics, and physical effects of sound; Crack array; Phase velocity; Group velocity; Analytical method; SH wave; Guided wave; Crack detection; Pipe; Torsional vibration; Magnetostrictive device; Non destructive test; Damaging
• ISSN: 0885-3010; 1525-8955; 0885-3010
• DOI: 10.1109/TUFFC.2011.2131

The lowest-branch torsional guided wave is very effective in pipe damage inspection because of its non-dispersive characteristics, but it cannot be used for the simultaneous identification of axial and circumferential locations of a defect in a pipe. Motivated by recent developments in magnetostrictive transducer technology, which is especially efficient in torsional and shear wave generation, the goal of this investigation is to extend this technology for simultaneous identification of the axial and circumferential locations of cracks by using shear horizontal (SH) waves. Unlike the conventional magnetostrictive patch method using a single complete patch wound around the pipe's circumference, the proposed method segments the patch into several pieces to generate SH waves propagating over the pipe surface. Accordingly, SH waves in a pipe are generated and sensed individually by a meander coil placed separately on each segment. By using two sets of segmented-patch arrays separated by some distance, the cylindrical surface of a pipe can be inspected both axially and circumferentially. After the underlying angular profile of the patch segment is investigated, experiments identifying the axial and circumferential locations of multiple cracks in a pipe are carried out to demonstrate the potential of the proposed methodology.