In neutron beam research, it is necessary for the shielding block and experimental equipment a dance floor in a nuclear reactor to travel in a fixed direction with little friction. However, precise travel is difficult to achieve due to factors such as vibration or gear backlash. We have imported air bearings from more developed nations to perform the role of moving instruments. In the beginning, an air bearing for use in three-dimensional measuring instruments similar to an air bearing was used; however, the performance was found to be insufficient. Accordingly, we collected data and conducted reverse engineering on this type of thrust pad. Through this process, it was confirmed that two issues were influencing the performance: the slant of the bottom of the air bearing and the bottom outside edge of the air bearing plate. The air bearing begins to move at 5 bar and moves smoothly without interruption at 7 bar. The result of this process was the development of a thrust pad which is superior in performance to the imported product and is being used in neutron beam research. We anticipate that this air bearing which has been developed will be used for experimental equipment which requires this type of precision in the future.

The Cold Neutron Research Facility(CNRF) is being built to produce a cold neutron which has peculiar physical property. In-Pool Assembly(IPA) was manufactured in a domestic factory, which is composed of moderator cell, heat exchanger, vacuum chamber, joint flange assembly and bracket etc. We had difficulties with the mechanical fabrication process due to the thin moderator cell. The special flange for the double flexible piping was developed. The tests of moderator cell, heat exchanger, vacuum chamber, double flexible pipe and IPA include the pressure test, normal temperature leak test and low temperature leak test. The moderator cell and heat exchanger were tested in the severe environmental condition and the burst tests of moderator cell were carried out. Above all, the bursting point took place at the area of the 0.01mm thinner place. It shows that the severe environmental test affects the bursting strength. The double flexible pipe welding at the IPA top plate was related with the arrangement of moderator cell in the vacuum chamber. Therefore the connecting welding of the double flexible pipe linked to sequent of the vacuum piping, helium piping and hydrogen piping. The fabrication, test and assembling of cryogenic in radiation zone were developed.