蒸汽发生器安全端焊缝位于蒸汽发生器房间, 该区域属于高剂量区。与蒸汽发生器安全端相连接的主管道具有外径大、管壁厚的特点, 同时由于主管道为离心铸造, 使用超声波检测的方法难以实施。而使用射线检测方法时, 只需将源头放置在合适位置, 工作人员即可离开。当曝光结束后, 再进入房间将底片取出, 检测过程中无需在房间逗留太久, 并且通过底片就可以对焊缝的质量进行评价, 因此射线检测较超声检测更具有适用性。介绍了蒸汽发生器安全端焊缝射线检测的技术要点。通过岭澳核电站役前检查的实践, 探讨了检测方法的适用性及可靠性。对于同类部件的在役检查, 提出了改进意见与方法。

The safety weld of steam generator is located in the SG(steam generator) room, and it is an area of high dose level. The pipeline has a major diameter and thick tube skin, and it is made by cast. So it is hard to inspect it with other NDT methods, such as ultrasound. Radiation inspection was chosed to detect the weld, it need only to place the radioactive source in the right position, then the inspector can leave. When the exposure is ended, the inspector can go into the SG room and take out the film. During the process, the inspectors don’t need to stay in the room too long, and the quality of the weld could be evaluated through the film, so it is more adaptive than ultrasound. The article describes the main points of inspecting the safety weld with RT method, it is proved the correctness and reliability by the practice in the Ling Ao Nuclear Power Station, and the improved methods and views for the testing in service was expressed at last.