NB/T 47013.3-2015超声检测标准中, 对Ⅱ型焊接接头给出了缺陷实际指示长度的修正公式, 但在实际超声检测中, 由于声场、工件几何形状的影响, 缺陷的实际指示长度与测量值之间存在偏差, 精确评定时需要修正。针对超声检测中曲率表面工件的外圆柱面、内圆柱面沿周向测出的缺陷指示长度的修正问题, 进行了讨论。得出结论: 如本着从严的原则, 对外圆柱面检测可以不进行修正的话, 那么对内圆柱面检测结果则应进行修正, 才能使产品符合标准的要求。

The formula indicating the actual length of the defect in the ultrasonic detection of welded joint is given in NB/T 47013.3-2015 ultrasonic testing standards, but in fact, because the sound effect of the workpieces, the deviation between the actual length and value measurement of defect indication exists, and therefore precise timing evaluation needs to be revised. Ultrasonic testing for the workpiece surface curvature in the outer cylindrical correction within the cylindrical surface along the circumferential direction of the measured length of flaw indication was discussed. Conclusions might be drawn that in the strict term in order to make the products meet the requirements of the standard, if the external cylindrical surface detection can not be modified, then the inner cylindrical surface detection should be modified.