journal article·2017-04Open access

EMAT pipe inspection technique using higher mode torsional guided wave T(0,2)

Nurmalia, N. Nakamura, H. Ogi, M. Hirao

Abstract

We developed a pitch-catch system based on electromagnetic acoustic transducers (EMATs) for pipe inspection, which moves inside the pipe in the axial direction. The first higher mode, T(0,2), of the torsional guided wave is transmitted and detected, and variations of amplitude and phase are measured while moving the EMATs. Several aluminum pipes containing dish-shaped defects are inspected, and the amplitude and phase show enough detection sensitivity. It is found that the phase measurement has better potential as a tool for quantitative inspection. The applicability of the technique for steel pipe is also confirmed.
Source: openaire · Quality: candidate unverified · Source record ↗

Research context

OpenAlex topics: Ultrasonics and Acoustic Wave Propagation · Non-Destructive Testing Techniques · Geophysical Methods and Applications

SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.

References (26)

Show source-provided references
1. Empirical structure for characterizing metal loss defects from radial magnetic flux leakage signal10.1016/j.ndteint.2010.05.006 ↗
2. Weak magnetic flux leakage: a possible method for studying pipeline defects located either inside or outside the structures10.1016/j.ndteint.2015.05.008 ↗
3. Application of eddy currents induced by permanent magnets for pipeline inspection10.1016/j.ndteint.2006.07.002 ↗
4. Assessment of wall thinning in insulated ferromagnetic pipes using the time-to-peak of differential pulsed eddy-current testing signals10.1016/j.ndteint.2012.07.004 ↗
5. High end inspection by filmless radiography on LSAW large diameter pipes10.1016/j.ndteint.2009.11.004 ↗
6. Defect detection improvement of digitized radiographs by principal component analysis with local pixel grouping10.1007/s10921-015-0290-z ↗
7. An SH-wave EMAT technique for gas pipeline inspection10.1016/S0963-8695(98)00062-0 ↗
8. Review of magnetostrictive patch transducers and applications in ultrasonic nondestructive testing of waveguides10.1016/j.ultras.2015.05.015 ↗
9. Achenbach · 1999
10. The reflection of the fundamental torsional mode from cracks and notches in pipes10.1121/1.1582439 ↗
11. Scattering of the fundamental torsional mode at an axial crack in a pipe10.1121/1.3277185 ↗
12. The effect of complex defect profiles on the reflection of the fundamental torsional modes in pipes10.1016/j.ndteint.2011.11.003 ↗
13. On the scattering of torsional elastic waves from axisymmetric defects in coated pipes10.1016/j.jsv.2012.04.013 ↗
14. The reflection of the fundamental torsional mode from pit clusters in pipes10.1016/j.ndteint.2011.11.006 ↗
15. Experimental investigation of mode conversion of the T(0,1) mode guided wave propagating in an elbow pipe10.7567/JJAP.50.046601 ↗
16. Mode conversion of torsional waves generated by electromagnetic acoustic transducer10.1063/1.4789141 ↗
17. Mode conversion and total reflection of torsional waves for pipe inspection
18. Circumferential and longitudinal defect detection using T(0,1) mode excited by thickness shear mode piezoelectric elements10.1016/j.ultras.2006.05.154 ↗
19. Torsional wave experiments with a new magnetostrictive transducer configuration10.1121/1.1904304 ↗
20. Generating and detecting torsional guided waves using magnetostrictive sensors of crossed coils10.1016/j.ndteint.2010.11.006 ↗
21. Failure analysis of natural gas pipes10.1016/j.engfailanal.2009.10.016 ↗
22. Physical principles of measurements with EMAT transducers
23. Hirao · 2017
24. Excitation of horizontally polarized shear elastic waves by electromagnetic transducers with periodic permanent magnets10.1063/1.326265 ↗
25. Three-dimensional investigation of the propagation of waves in hollow circular cylinders. I. analytical foundation10.1121/1.1907753 ↗
26. Mode conversion behavior of SH guided wave in a tapered plate10.1016/j.ndteint.2011.10.004 ↗