| 摘要 |
PURPOSE:To detect the presence of a fine pore extremely with ease by sealing a liquid in an airtight gap costituted by a transparent board and a plate, and then monitoring the entrance of a small bubble when the liquid is decompressed. CONSTITUTION:On one flank of a transparent board 1, a packing 4 to be brought into contact with the gasket 3 of a plate to be tested is stuck and fixed annularly, and the packing 4 and the gasket 3 of the plate 3 are abutted each other and retained temporarily to block through holes 5a-5c at four corner parts. While a vacuum pump 12 is driven, valves 10 and 11 are opened to suck up water in a tank 13 with an open water level, and the water level rises in a gap 15 between the transparent board 1 and plate 2 through a feed water pipe 6 and then reaches a waste tank 8 through a waste pipe 7. Then, the valve 10 is closed and the internal space of the waste tank 8 is decompressed to 200- 300mm.Hg by the vacuum pump 12, so that the water in the gap 15 is dcompressed as well. If the plate has a fine pore, air enters the water and rises as an air bubble. |
