[en] This paper introduces the function of TNPS refueling machine, the structure of rod cluster assembly protective jacket, and the condition of functionality recovering. It also describes some problems found when fuel assemblies and rod cluster assemblies are rearranged and replaced during refueling outage, as well as the analysis and processing of problems. In addition, it investigates the general causes of problems by disassembling inspection on rod cluster assembly protective jacket. (authors)