Evaluation of mechanical cutting for disassembly of fast reactor fuel assemblies

高速炉燃料集合体の機械式解体技術の評価

西川 秀紹*; 竹内 正行 ; 北垣 徹  ; 井上 哲徳*; 佐藤 勇*

Nishikawa, Hidetsugu*; Takeuchi, Masayuki; Kitagaki, Toru; Inoue, Akinori*; Sato, Isamu*

In the fuel reprocessing of fast reactors, it is necessary to cut and pull out the wrapper tube from the fuel assembly, and then cut and remove the fuel pins. Mechanical cutting has no problems such as causing thermal damage to the fuel pins due to laser cutting, and the cutting position can be accurately set, but the replacement of the cutting-off wheel (CW) due to wear or breakage is a problem. In this study, durability of the CBN CW was evaluated based on the grinding ratio obtained from the cutting test using the material of the fuel assembly, and the grinding ratio was considered from the viewpoint of material physical properties. In addition, the effect of preventing the CBN CW breakage by controlling the feed speed, and the cutting mechanism from the CBN CW contact area were considered from evaluation of the CBN CW rotation motor current.