Pilger die and pilger mandrel for manufacturing dashpot tube for nuclear fuel assembly and method of manufacturing the pilger die and the pilger mandrel

摘要

A pilger die and a pilger mandrel which are used to produce a dashpot tube which can be used in a nuclear fuel assembly having an outer diameter of 31.75 mm or less and an inner diameter 25.654 mm or less, by processing a reduced expression zirconium alloy tube in two pilgering processes (a first step pass and a second step pass) using a single pilgering apparatus. Furthermore, provided are methods of manufacturing the pilger die and the pilger mandrel, and the dashpot tube for the nuclear fuel assembly. The dashpot tube can be manufactured by the single pilgering apparatus provided with the pilger die and the pilger mandrel.