MARINE CRAFT Russian patent published in 2006 - IPC B63B11/04 B63B13/00 

FIELD: shipbuilding; building of marine craft equipped with group of ballast tanks and designed for transportation of cargoes on deck.

SUBSTANCE: marine craft has pressure hull with group of ballast tanks equipped with ballast system with tubes for filling the tanks and vent tubes. At least one group of ballast tanks is equipped with common vent-overflow manifold mounted inside said tank above waterline. Manifold is provided with vent and overflow branch pipes. Each tank is provided with at least one such branch pipe whose open end is located under tank top. Each end section of manifold is provided with vent tube for admitting and evacuating air and at least one discharge outboard pipe line fitted with check valve. Vent tube of said end section of manifold may be connected directly to manifold and may be mounted on ballast tank top. It is good practice to equip vent-overflow branch pipes of manifolds located in zone of assumed damage of craft with automatic units to exclude admission of water from common vent-overflow manifold to tanks.

EFFECT: increased productivity; enhanced safety of cargo handling operations at absence of blockage of weather deck.

4 cl, 6 dwg