| 摘要 |
<p>A shipboard storage tank for liquids, such as petroleum products or chemicals. To prevent pressure buildup, and to permit overflow during filling, a vent and overflow conduit is provided. In order to prevent this vent and overflow conduit from becoming a source of pollution if the ship should sink and also in order to prevent loss of the contents of the tank upon sinking, the invention provides an anti-pollution valve installed in the conduit, which automatically closes the conduit, should the ship sink. The anti-pollution valve is actuated to its closed position by the hydrostatic pressure as the ship sinks and it automatically equalizes the pressures between the sea and the liquid within the tank as the vessel sinks to deeper depths. Transient effects, such as surface waves, are prevented from actuating the valve. The anti-pollution valve also includes means that make it possible to dump the liquid out from the tanks of sunken ships and thereby salvage it.</p> |
