| 摘要 |
<p>An underwater gas/liquid reservoir 1, particularly designed to be used as a ballast/buoyancy tank in an offshore drilling platform, has a pressurized supply duct 2 for introducing gas into the reservoir to control the liquid level therein. The gas supply duct has two openings 8, 11, one near the bottom of the reservoir and the other near the top. A movable straddle packer 14 is disposed in the gas supply duct for selectively closing the bottom opening 8 so that gas is allowed to flow only through the top opening 11 of the supply duct. The packer can also be positioned to uncover the bottom opening 8 of the gas supply duct. In operation, the liquid level within the reservoir is controlled by the introduction or release of pressurized gas into or from the reservoir through the openings of the gas supply duct either to force liquid from the reservoir or to allow liquid to flow into it.</p> |
