A Rapid and Accurate Technique With Updating Strategy for Surface Defect Inspection of Pipelines

Abstract

Defect inspection in pipes at the early stage is of crucial importance to maintain the ongoing safety and suitability of the equipment before it presents an unacceptable risk. Due to the nature of detection methods being costly or complex, the efficiency and accuracy of results obtained hardly meet the requirements from industries. To explore a rapid and accurate technique for surface defects detection, a novel approach QDFT (Quantitative Detection of Fourier Transform) has been recently proposed by authors to efficiently reconstruct defects. However, the accuracy of this approach needs to be further improved. In this paper, a modified QDFT method with integration of an integral coefficient updating strategy, called QDFTU (quantitative detection of Fourier transform of updating), is developed to reconstruct the defect profile with a high level of accuracy throughout iterative calculations of integral coefficients from the reference model updated by a termination criteria (RMSE, root mean square error). Moreover, dispersion equations of circumferential guided waves in pipes are derived in the helical coordinate to accommodate the stress and displacement calculations in the scattered field using hybrid FEM. To demonstrate the superiority of the developed QDFTU in terms of accuracy and efficiency, four types of defect profiles, i.e., a rectangular flaw, a multi-step flaw, a double-rectangular flaw, and a triple-rectangular flaw, are examined. Results show the fast convergence of QDFTU can be identified by no more than three updates for each case and its high accuracy is observed by a smallest difference between the predicted defect profile and the real one in terms of mean absolute percentage error (MSPE) value, which is 6.69% in the rectangular-flaw detection example. INDEX TERMSCircumferential guided wave, Hybrid FEM, reconstruction, reference model, updating strategy. YIHUI DA received the B.S. degree in theoretical and applied mechanics from Henan Polytechnic University, Henan, China, in 2009, and the M.S. degree in general and fundamental mechanics and the Ph.D. degree in engineering mechanics from the Nanjing University of Aeronautics and Astronautics, Nanjing, China, in 2014 and 2018, respectively.Since 2019, he has been working as a Postdoctoral Researcher with the Nanjing University of Aeronautics and Astronautics. His research interests include the numerical modeling of ultrasonic guided waves, ultrasonic nondestructive evaluation, and signal processing.

Modeling of axisymmetric ultrasonic waves reflected from circumferential cracks in a pipe based on a rigorous analytical theory and implementation on distributed devices

“…Moreau et al [19] introduced the adaptive mesh and surface integral method to enhance FE modelling of wave scattering from a defect, with sophisticated discretization being only applied with respect to the defect plane. The combination of cross-section mesh and axial orthogonal factorization constitutes the so-called semi-analytical finite-element (SAFE) method which has been used in modelling guided waves within railways [20,21], metallic plates [22,23] and pipes [24][25][26]. In another way, the computational cost of three-dimensional FEM can also be reduced by improved discretization.…”

Intelligent Structural Defect Reconstruction Using the Fusion of Multi-Frequency and Multi-Mode Acoustic Data

“…Despite a great deal of progress on the subject of UGWT, many methods currently available are only capable of providing a qualitative assessment of structural defects [3], [4]. Consequently, the inverse scattering problem, focusing on quantitative determination of the defect shape and size in the use of various reflection and transmission signals of ultrasonic guided waves, is always a hot research topic in the field of UGWT [5]- [8].…”

“…The ultrasonic array, one of the effective quantitative UGWT technology, has superior features including the large scanning range and high detection accuracy [8]. In earlier ultrasonic array work by Hutchins [10], [11], Achenbach [12], and Degetekin [13], a parallel projection technique with the velocity and attenuation of Lamb waves as the input was developed for the tomographic reconstruction.…”