衍射时差图像处理与缺陷识别技术综述

Overview of Time of Flight Diffraction Image Processing and Defect Recognition Technology

焊缝是压力容器的质量薄弱环节,焊缝缺陷直接影响压力容器的安全运行。衍射时差(time of flight diffraction,TOFD)检测是目前焊缝质量评价的主要手段。随着TOFD成像检测技术的不断发展,TOFD成像结果自动判读的不足,正成为制约TOFD检测规模化应用的障碍。图像处理和缺陷识别是TOFD成像检测的技术关键。将TOFD图像处理技术归纳为噪声去除、直通波处理、曲线拟合和图像分割,将TOFD缺陷识别技术归纳为特征提取和模式分类,详细介绍了中外的相关研究成果,并对TOFD图像分割、特征提取和缺陷分类识别的研究提出了建议。

Weld is the weakness of pressure vessel quality,and the weld defect directly affects the safe operation of pressure vessel.Time of flight diffraction(TOFD)detection is the main method of weld quality evaluation.With the rapid development of TOFD imaging detection technology,the lack of automatic interpretation of TOFD images is becoming an obstacle to the large-scale application of TOFD detection.Image processing and defect recognition are the key technologies of TOFD imaging detection.TOFD image processing technology was summarized as noise removal,lateral wave processing,curve fitting and image segmentation,and TOFD defect recognition technology was summarized as feature extraction and pattern classification.The related research results at home and abroad were introduced in detail,and suggestions on the research of TOFD image segmentation,feature extraction and defect classification were discussed.