Floating lid for container - has liquid sealing ring between container and lid with sealing liquid of lower density to accommodate expansion of contained liquid

摘要

The floating lid (1) rests on the surface of the liquid (7) in the bore of the container (8). The central part of the lid has a reservoir (3) which contains liquid of a lower density than the liquid in the container (8). The central reservoir connects with the outer flange (2) of the lid via horizontal passages (5). The liquid leaking from the central tank forms a sealing ring (6) which also floats on the surface of the liquid (7).