NDT Technology

NDT Technology

Detection of dimensions of axisymmetric surface defects located on the pipe using the first order symmetric torsional guided waves

Document Type : Original Article

Authors
Amin Yaghootian 1
Ali Valipour 1
Armin Mokhtarizadeh 2
1 Department of Mechanical Engineering, Shahid Chamran University of Ahvaz
2 Department of Mechanical Engineering,, Shahid Chamran University of Ahvaz
10.30494/jndt.2021.277451.1067
Abstract
Nowadays, ultrasonic guided waves are widely used in non-destructive inspection of pipelines due to their high accuracy and speed. One of the advantages of using the symmetric modes of guided waves is simplicity in propagation and easier interpretation of the results. This has led to their significant use in the inspection of pipelines. Depending on the type of damage, defects can appear on the surface of pipe in different forms such as cracks, cavities, porosity, etc. In this paper, by using the propagation of the first-order torsional symmetric mode, symmetric defects in the different dimensions and sizes are investigated. The various factors such as the excitation frequency, the thickness of pipe and position of the defects are investigated to determine the effect of each on the reflection. Also, in this study, the reflection coefficients for the defects with different sizes have been calculated and their related diagrams have been drawn to use them for estimating the geometric dimensions of symmetrical defects. Finally, with the study of reflection coefficients, it is observed that the excitation frequency, the thickness of pipe and position of the defects can be considered as factors that affecting the reflected wave reflection.
Keywords
Wave Propagation
Non Destructive Testing (NDT)
Reflection Coefficient
Guided Waves
Symmetric Defects

Subjects

[1]     جعفری، ح، (1385) ، آزمون فراصوت و کاربرد آن در صنایع، چاپ اول، تهران، دانشگاه شهید رجایی.
[2]     Demma, A., Cawley, P., Lowe, M., Roosenbrand, A.G., (2004), Pavlakovic, B., The reflection of guided waves from notches in pipes: a guide for interpreting corrosion measurements, NDT&E International, Vol 37, pp167-180.
[3]     Demma, A., Cawley, P., Lowe, M., Roosenbrand, A.G., (2003) The reflection of the fundamental torsional mode from cracks and notches in pipes. The Journal of the Acoustical Society of America, 114(2), pp.611-625.
[4]     Lowe, M.J.S, Alleyne, D. N., Cawley, P., (1998), The Mode Conversion of a Guided Wave Part Circumferential Notch in a Pipe, Journal of Applied Mechanics, Vol 65(3), pp 649-656.
[5]     Niu, X., Duan, W., Chen, H. P., Marques H. R., (2018), Excitation and propagation of torsional T(0,1) mode for guided wave testing of pipeline integrity, Vol 131, pp341-348.

  • Receive Date 15 March 2021
  • Revise Date 08 April 2021
  • Accept Date 15 April 2021