应力腐蚀裂纹的检出和定量-PAUT三向显示图解读

Interpretation of Three Types of PAUT Display for SCC Detection and Depth Sizing

介绍了满足断裂力学验收条件要求、依据超声相控阵成像数据,对SCC(应力腐蚀裂纹)进行检测和测深定高的CI(计算机成像)技术应用的最新进展。详述用超声三向图像显示进行数据评定的过程和方法,包括B型显示(横断面视图)、C型显示(俯视图)和D型显示(纵断面视图)。数据评定解析使用由SCC试样获取的相控阵数据。此法强调以下三要素的重要性:(1)波型选择对重建SCC图像;(2)SCC端部回波识别对避免错判误定;(3)纵断面视图对评估SCC深度轮廓。企望对国内承压设备在役无损检测和定量评价提供有用借鉴。

The latest international development of a PAUT image-based data evaluation procedure for detection and depth sizing of SCC （ Stress Corrosion Cracking ） is presented, in order to meet the code re- quirements on a fracture mechanics based acceptance criteria. The developed procedure details data evalua- tion processes and techniques based on ultrasonic images, including cross-sectional views （ B-scan ）, plan views （ C-scan ） and end views （ D-scan ）. The explanations of the data evaluation techniques are suppor- ted by the phased array data taken on a test sample with SCC. The developed procedure emphasizes the im- portance of the following three major factors, ie： （1） the wave mode selection for precise reconstruction of SCC images （2） SCC tip echo identification for avoiding false call; （3） the end view for estimating SCC depth contour. The intention is to provide a source of reference for the in-service NDE and quantity evalua- tion of pressure equipment in our country.