根据锅炉小径管焊缝的缺陷分布范围，研制出系列超声相控阵检测的对比试块，并进行了模拟与自然缺陷的检测试验。测试采用1 mm横孔制作距离-波幅曲线，对不同外径与壁厚的内外壁缺陷进行定量与指示长度测定，修正了传统检测的误区，建立了超声相控阵小径管焊缝的检测工艺方法。

A series of ultrasonic phased array inspection contrast test blocks were developed according to the distribution range of the boiler pipe weld defect, and at the same time tests were conducted on the simulation and natural defects, respectively. By making distance amplitude curve for 1mm diameter horizontal hole, we quantified and measured indicating length of defects both inside and outside of the tube with different diameter and thickness, and thus corrected the errors of the traditional detection and established the testing method of ultrasonic phased array for small pipe weld.