| 摘要 |
PURPOSE:To improve the resistance to leakage by a method wherein silica particles are impregnated in a passage wall, a ceramic made heat exchanger being immersed in a liquid, in which special colloid type silica is impregnated. CONSTITUTION:A vessel 23 contained impregnated liquid 22 is placed on a base stand 21, and the heat exchanger 11 is put in the impregnated liquid 22 and a part of the heat exchanger 11 is exposed from said liquid 22. The impregnated liquid 22 is mainly composed of colloid type silica in which silica particles of which particle diameter being under 20mum are dispersed in a water at the density of under 50wt%. Next, the vessel 23 is covered with a chamber 25 from upside, and between the chamber 25 and the base stand 21 is sealed by a seal member 26 which is attached at the under part of the chamber 25, and the pressure in the chamber 25 is reduced by driving an exhaust pump 27 and the heat exchanger 11 is exposed to the lower pressure. A leak valve 28 is connected to the chamber 25, and the reduced pressure condition is removed by introducing air in the chamber 25 by the operation of the leak valve 28. Thereby, impregnated liquid 22 smoothly enters in an evacuated hollow space of the heat exchanger 11, and silica particles are impregnated inside of the passage wall of the heat exchanger 11, and the sealing of the passage wall is carried out. |
