The invention relates to the field of floating production
oil storage ships, in particular to a
ballast tank hatch cover of a floating production
oil storage device, which comprises an
oil storage device, the oil storage device comprises an outer protection tank body, a
ballast tank body and a
ballast tank hatch cover, and an
inert gas injection
pipe is mounted on the upper surface of the
ballast tank hatch cover. Adjusting mechanisms are installed on the two sides of the
inert gas injection
pipe and located in the
ballast tank cover, limiting sliding blocks are installed on the outer sides of the extending plates, guiding sliding grooves are formed in the positions, located on the inner side walls of the
swash plates, of the outer sides of the limiting sliding blocks, and telescopic mechanisms are installed in the adjusting mechanisms and located in the
swash plates. The telescopic mechanism comprises a first
bevel gear, a second
bevel gear, a meshing lead screw and a gear rotating seat. After the
inert gas injection
pipe is integrally and externally connected with an
inert gas source, and the
inert gas is used for integrally discharging air remained in the
ballast tank body, so that the ballast tank body can be used as a temporary collection mechanism, and the transportation efficiency and safety of oil are ensured.