CLOSED-LOOP PRE-COOLING METHOD OF CRYOGENICALLY COOLED APPARATUS, AND ITS DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a pre-cooling method of a cryogenically cooled apparatus capable of reducing a cryogenically cooling agent (helium amount) required for pre-cooling, and eliminating a risk related to the introduction of nitrogen into a cryogenic vessel, and simplified in a pre-cooling procedure, and to provide its device. SOLUTION: This device for pre-cooling a cryogenically cooled apparatus housed in a cryogenic vessel 26 comprises: a first closed-loop cooling circuit 30 with a heat transferring fluid enclosed therein; a circulator 32 for causing the heat transferring fluid to circulate around the closed-loop cooling circuit; and a heat extractor 34 structured to extract heat from the heat transferring fluid, where the closed-loop cooling circuit carries the heat transferring fluid into and from an internal space of the cryogenic vessel 26. COPYRIGHT: (C)2007,JPO&INPIT