| 摘要 |
<p>The method involves providing an element i.e. flange, of guide (4) with a recess i.e. chamber, surrounding a tubular shuttle (3). The recess is formed laterally by an internal surface of the guide and an external surface of the shuttle and longitudinally by contact zones between the external surface and extension of the internal surface. Pressure greater than/equal to pressure of liquid i.e. liquefied natural gas (1a) in a tank (1), is maintained in the recess during the displacement of the shuttle along a vertical direction (5) by injecting inert gas e.g. nitrogen, into the recess. An independent claim is also included for an air lock for creating input/output of instrument in a tank containing fluid at pressure greater than atmospheric pressure.</p> |
