用于腐蚀介质环境下的法兰，密封面的腐蚀缺陷容易使其泄漏，影响安全生产，导致危害性的后果。利用超声相控阵检测技术<参考文献原文>声束角度可变和动态聚焦的优点、适合复杂结构件以及实时成像等特点，通过结构分析、声场模拟，试验研究和现场检测应用，确定了法兰超声相控阵针对性检测工艺，实现了不拆卸从法兰外部对密封面腐蚀缺陷进行有效检测。

Under corrosion environment, the flange is susceptible of corrosion defects on the sealing surface resulting to the leakage, thus affect the safety of production and leading to harmful consequences. In this paper, by making use of the features of ultrasonic phased array detection technology, i.e. the variable beam angle and the advantages of dynamic focusing, suitable for complex structures and real-time imaging, etc., the ultrasound phased array testing procedures targeted for the flange was determined through structural analysis, sound field simulation, experimental research and the applications of field testing. Effective detection of corrosion defect on the sealing surfaces from the flange external side was achieved without disassembling it.