| 摘要 |
PURPOSE:To perform easily pressure test of an optional part by cooling a part of a tube in a closed section to freeze water and using increase of the volume due to freezing to raise a water pressure in the closed section. CONSTITUTION:When water is packed in tubes 31 and 33 and a liquid nitrogen or the like is charged into a cooling jackets 36 and 36' and is cooled, water in these parts is frozen and expanded to close tubes 31 and 33, and ice plugs 39 and 39' are formed. When cooling is continued gradually, expansion due to freezing of ice plugs 39 and 39' is advanced, and ice plugs are made thicker gradually to compress water sealed in tubes 31 and 33. The intra-tube pressure at this time is measured by a strain gauge 40 and a pressure gauge 41. |
