蒸汽发生器二次侧外来物可造成传热管外壁磨损，对蒸汽发生器传热管完整性产生危害。简述了外来物在役检查要求，对传热管涡流在役检查期间发现的自由段外壁信号进行了BOBBIN探头、MRPC探头的数据分析，结合二次侧视频检查等方式，确认该信号为外来物造成的外壁磨损，并给出了后续在役检查信号的跟踪处理建议。

Steam generator secondary side foreign object may cause heat exchange tube wear which might threaten the integrity of steam generator tubes. A brief description was given on in-service inspection requirements for foreign objects. During the in-service eddy current inspection of steam generator tubes, an outer wall signal was found. Through BOBBIN probe and MRPC probe data analysis combined with secondary side video inspection, the tube outside wear caused by foreign objects was confirmed. Suggestions on monitoring the signal in the following in-service inspections were given.