面向长输管道螺旋焊管的弯曲模态超声导波定量化检测关键技术研究

Spiral welded pipes are important to long-distance pipeline. The oil & gas explosions caused by the deterioration of spiral welded pipes structure health status have occurred frequently in recent years. As the complex structure of spiral welded pipe, there is no efficient long range NDT method. The project introduces a flexural ultrasonic guided wave quantitative test method for spiral welded pipes in long-distance pipeline. The appropriate mode and frequency of guided wave are determined based on the propagation model of flexural ultrasonic guided wave, which makes the propagation pathway of guided wave parallel with spiral weld. The pathway parallelled with spiral weld eliminates influence of spiral weld on guided wave propagation. The transducer array is installed perpendicular to spiral weld. The coefficient and time delay can be calculated by deconvolution in the helical coordinates, which makes ultrasonic guided wave focus. By multi-scale C-scan, the data fusion of defect edge and amplitude will realize the efficient quantitative defect description. The project lays an important foundation for the guided wave application in long range NDT of spiral welded pipes.

螺旋焊管是一种重要的长输管道用管，其结构健康状况恶化引发的油气泄漏爆炸事故近年来屡有发生。由于螺旋焊管结构复杂，目前尚缺乏高效的螺旋焊管长距离检测方法。本项目提出了一种面向长输管道螺旋焊管的弯曲模态超声导波定量化检测方法，根据螺旋焊管弯曲模态超声导波传播方向数学模型，选择合适的模态和频率激励弯曲模态超声导波，使弯曲模态超声导波的传播轨迹与螺旋焊缝平行，消除螺旋焊缝对超声导波传播的影响。沿垂直螺旋焊缝方向布置超声导波换能器阵列，在螺旋坐标系下通过反卷积算法获得各通道换能器的权重系数和信号延时，实现各通道激励的超声导波在聚焦点汇聚。在此基础上进行多尺度相控阵C扫描，融合缺陷边缘信息和C扫描图像幅值信息实现螺旋焊管缺陷的高效定量表征，为超声导波技术在螺旋焊管长距离无损检测的推广应用奠定了重要基础。

螺旋焊管是一种重要的油气长输管道用管，其结构健康状况恶化引发的油气泄漏爆炸事故近年来屡有发生。本项目研究的一种面向油气长输管道螺旋焊管的弯曲模态超声导波定量化检测方法，旨在激励出平行于螺旋焊缝的弯曲模态超声导波，实现对螺旋焊管的定量化检测。本项目建立了弯曲模态超声导波传播特性的数学模型，获得了弯曲模态超声导波传播特性分析方法；获得了一种基于纵向和扭转轴对称模态磁致伸缩超声导波换能器改进而来的纵弯和扭弯模态超声导波换能器设计方法；获得了一种全域快速低频扫查和缺陷区域高频精细详查相结合的超声导波多分辨率C扫描稀疏成像方法。本项目的研究成果经过优化，可以集成到目前的超声导波管道检测平台，拓展超声导波管道检测平台的检测应用范围。