Yibo Li, Liying Sun, Zhidong Song, Yuankai Zhang
State Key Laboratory on Precise Measuring and Testing Technique and Instrument, Tianjin University, Tianjin 300072, China.
Ultrasonics. 2006 Dec 22;44 Suppl 1:e1111-6. doi: 10.1016/j.ultras.2006.05.108. Epub 2006 Jun 6.
Ultrasonic guided wave is introduced as a new non-destructive long range pipe inspection method. It can be used to inspect pipe which is inaccessible to other conventional NDT methods, and rapid, long distance inspection can be achieved. An investigation of the guided ultrasonic waves traveling along pipe with special geometry characteristics, such as elbow, several girth welds, and some artificial defects is described. In this paper, factors that may cause attenuation of ultrasonic guided waves are discussed and energy attenuation of longitudinal and torsional guided waves is studied on an experimental pipe having seven girth welds. Good agreement has been obtained between the experiments and the predictions. In the end, the detection sensitivity and locating precision of two guided waves, namely longitudinal and torsional, were compared on defects, such as notch, burr and branch.
超声导波作为一种新型的无损长距离管道检测方法被引入。它可用于检测其他传统无损检测方法无法触及的管道，并且能够实现快速、长距离检测。本文描述了对沿具有特殊几何特征（如弯头、多个环焊缝和一些人工缺陷）的管道传播的导波进行的研究。文中讨论了可能导致超声导波衰减的因素，并在一根有七个环焊缝的试验管道上研究了纵向和扭转导波的能量衰减。实验结果与预测结果取得了良好的一致性。最后，比较了纵向和扭转这两种导波在缺口、毛刺和支管等缺陷上的检测灵敏度和定位精度。
