在对焊缝超声检测检出缺陷数字定量分析的基础上，探讨了在不同检测灵敏度时检出缺陷直径当量的变化，以及不同尺寸对比试块的等效代用方法。为检测人员确定合适的检测灵敏度、等效选用检测对比试块和更直接了解缺陷情况提供参考，也为制定科学合理的检测验收标准提供帮助。

On the basis of the quantitative analysis of the amount of the defects detected when weld ultrasonic test, discussion was made on the change of the equivalent defect diameter under different test sensitivity, and on the equivalent substitute method of different size ultrasonic blocks. It can help test persons to confirm suitable test sensitivity, choose suitable equivalent ultrasonic block and understand the condition of the defects more directly. It can also help test persons to constitute scientific and reasonable test acceptance standards.