弯管焊缝曲表面超声相控阵成像检测

Ultrasound Phased Array Imaging on Curved Surface For Weld Inspection of Elbow Pipe

介绍弯管焊缝用超声相控阵检测(PAUT)安全取代射线照相检测(RT)的方法要领和细节。针对弯管焊缝沿圆周方向弯头表面几何形状变化特点,提出环焊缝用超声相控阵全聚焦法(TFM)进行成像检测,可获得高分辨力图像,且灵活性好。为验证所提出的方法,对声波在弯管壁内的传播,通过仿真平台,作了数值模拟。仿真结果表明,该法能准确测出反射源位置。最终实验证明:以此法取代RT,适用于不同尺寸的弯管环焊缝缺陷的探、判、测、评,满足相关规范标准要求。

This article introduces the method essentials and details using ultrasound phased array tes- ting （PAUT）, as a safe replacement of RT technique to inspect welds of elbow pipes. Facing the challenge issues caused by the geometrically varying surface along the circumferential direction, imaging by a total focusing method （TFM） is provided for the weld inspection with high resolution images and good flexibil- ity. To verify the proposed method, a numerical simulation of wave propagation on an elbow pipe is made through the simulation platform. The results show the proposed method can precisely localize true reflec- tor position. The final experiments prove that the method can replace RT to inspect various actual pipes for flaw detection, measurement, characterization and evaluation, meeting the relevant code and standard re- quirements.