管座角焊缝由于结构特殊、受力复杂，在焊接过程中容易出现未焊透、未熔合等危险性缺陷，在运行过程中易产生应力集中。针对小径管管座角焊缝的结构特点，设计制作了两种不同形式（安放式、插入式）的角焊缝对比试块，用于调整检测灵敏度以提高检测精度。利用制作的典型缺陷试样进行试验，总结形成了小径管管座角焊缝的相控阵检测专用工艺方案。通过在火力发电机组安装和检修工程中的应用，验证了检测工艺的可行性和准确性。该检测工艺的制定可为相控阵超声检测技术在管座角焊缝检测中的推广应用提供参考与借鉴。

Because of unique structure and complex stress, the socket fillet weld of pipe usually has dangerous defects arising from incomplete penetration and fusion during welding process, and yields stress concentration in the operation process. According to the structural characteristics of socket fillet weld of small-diameter pipe, two different types of reference blocks (placement type and insertion type) were designed and manufactured, and they were used to adjust the detection sensitivity to improve the detection accuracy. Typical defect samples were made for experimental research.The unique phased array inspection technology for socket fillet weld of small-diameter pipe was summarized. The feasibility and accuracy of the inspection technology were confirmed by the application in the installation and maintenance of thermal power units. The development of this testing technology provides a reference for the popularization and application of phased array ultrasonic testing technology in socket fillet weld detection.