Abstract

The pipelines are commonly existing in the oil, gas and chemical industry. Ultrasonic guided wave with large-scale and long-distance detection capacity is extensively used for the nondestructive testing of all kinds of pipelines. In the past the majority of published works on the reflection from defects have been done mainly by studying amplitude characteristics of reflection coefficient. Phase characteristics is one of the most important relationships between an incident wave and its reflection wave in inspecting pipelines. From the standpoint of reflection coefficient and acoustic impedance, the phase characteristics are investigated by theoretical analysis in this paper firstly. Then a method based on the phase characteristics of guided wave is proposed for pipes inspection, and its stability and validity are verified by numerical experiments, and the fundamental torsional mode T(0, 1) interacting with rectangular notches with different geometries in pipes are carried out in finite element software ABAQUS. By calculating the similarity coefficient of guided-wave reflection signals and reference signals, the types of the defects can be confirmed and recognized, and the results including circumferential information of the pipes are visualized by guided-wave B-scan imaging technique. The research has important value in engineering application and the proposed method provides a new research perspective for the detection and characterization of defects in pipelines.

How to Cite:

Liu, W. ., Tang, Z. . & Lv, F. ., (2019) “Research on three-dimensional information acquisition of changes in the pipe cross section based on circumferential scanning and phase characteristics”, Review of Progress in Quantitative Nondestructive Evaluation .