为实现在役井口阀门内部阀杆腐蚀情况的检测与评价，针对井口阀杆难以拆卸，磁粉、涡流、超声等无损检测方法难以直接穿透阀体进入内部检测等关键问题，提出了一种端部激励的相控阵超声检测方法。首先使用COMSOL有限元分析软件建立仿真模型，研究了典型阀杆结构的声场分布规律并分析结构回波特征，然后制作缺陷深度为2~8 mm的阀杆试件，对刻有人工缺陷的阀杆试件进行检测，并装入阀门内部进行检测，完成对阀杆特征结构与缺陷的定位。仿真和试验结果表明，在阀杆端部进行相控阵超声激励可以有效地识别阀门内部深度为2 mm的缺陷，验证了在不拆卸阀门内部阀杆的情况下，对其进行相控阵超声检测的可行性。

To achieve the detection and evaluation of corrosion on the internal valve stem of in-service wellhead valves, a phased array ultrasonic testing method with end excitation was proposed to address key issues such as difficulty in disassembling and testing the wellhead valve stem, and difficulty in directly penetrating the valve body for internal testing using non-destructive testing methods such as magnetic powder, eddy current, and ultrasound. Firstly, a simulation model was established using COMSOL finite element analysis software. The sound field distribution pattern of typical valve stem structures was studied and the echo characteristics of the structure was analyzed. Then, valve stem specimens with defect depths of 2-8 mm were manufactured, the valve stem specimens with artificial defects were tested and installed inside the valve for testing, the positioning of the valve stem characteristic structure and defects was performed. The simulation and experimental results indicated that phased array ultrasonic excitation at the end of the valve stem can effectively identify defects with a depth of 2 mm inside the valve, verifying the feasibility of phased array ultrasonic testing without dismantling the valve stem.