直缝焊管焊缝超声波检测中误判案例及分析

用多通道自动超声波探伤系统对φ559 mm×10 mm×12 000 mm直缝埋弧焊管纵向焊缝进行检测时,发现有些焊管局部段出现报警现象,检验人员对这些有异常反射的信号(伪缺陷)进行了分析和再检测试验。结果表明:内、外焊缝的焊偏是造成此次误判的主要根源;数字式探伤仪显示的信息与工件内实际情况的差别也是造成误判的另一因素;在检测过程中如遇到疑问时,采用多种检测方式进行综合判断是必要的。

Miscarriage of Justice Cases Introduction and Analysis on Weld Ultrasonic Testing for Longitudinal Steel Pipe

Adopting multi-channel ultrasonic testing system to detect longitudinal weld of φ559mm×10mm×12000mm SAWL pipe,it found alarm in some parts of steel pipe.The inspectors analyzed and retested these false defects,the results indicated misalignment of inside and outside weld was the main reason of miscarriage of justice;the difference between information which was showed in digital flaw detector and actual situation was the other factor;during detection course,adopting many kinds of inspection methods to carry out judgment was necessary,if meet some questions.