射线检测是核电站建造过程中保障焊缝焊接质量的重要手段，但其存在一定的局限性，包括面积型缺陷检出率低、存在辐射安全风险、检测效率低、检测成本高等。针对壁厚大于12. 7 mm的细晶铁素体钢管道焊缝制定了相控阵超声检测工艺，并与传统射线检测的缺陷检出率、缺陷定位误差和缺陷定量误差等进行了对比分析。结果表明，相控阵超声检测能够达到甚至优于传统射线检测的检出能力，具有广阔的应用前景。

Radiographic testing is an important means to ensure the quality of welds during the construction of nuclear power plants, but it has certain limitations, including low detection rate of area defects, radiation safety risks, low inspection efficiency, and high inspection costs. This paper developed the Phased Array Ultrasonic Testing (PAUT) procedure of fine-grainted ferritic steel pipe welds with more than 12 mm thickness. Also the defect detection rate, quantitative deviation and location error of PAUT were analyzed by constrast with that of RT. The results show that phased array ultrasonic testing can reach or even surpass the detection ability of traditional radiographic testing, and has broad application prospects.