JPS5810317B2 - Offshore storage tanks for flammable liquids - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a marine storage tank for flammable liquid that is installed floating on the sea.

In recent years, offshore oil stockpiling has been considered with the aim of ensuring a stable and sustainable supply and safe storage of oil, and a candy-shaped tank floating on the sea surface is used as an offshore storage tank for this purpose. Are known.

However, in such conventional offshore storage tanks, the mounting support (the height from the water line to the top of the tank) changes depending on the increase or decrease in the amount of oil in the tank, and the mounting support changes particularly when the amount of oil is low. As the wind load on the tank increases, the oscillation of the tank itself also increases, so it is necessary to increase the capacity of the tank's mooring device.

Also, when the tank is not fully loaded with oil, the space inside the tank is filled with gas, which is dangerous.

This invention has been made in view of the above-mentioned circumstances, and is a flammable liquid that does not change the mounting support due to an increase or decrease in the amount of flammable liquid in the tank, and does not cause the tank to be filled with gas. The purpose is to provide marine storage tanks for liquids.

This invention will be explained in detail below with reference to the drawings.

FIG. 1 shows an embodiment of the present invention, and a marine storage tank includes a tank upper body (first tank body) 1 floating on the sea surface, and a tank lower body fitted from below into the upper body 1. (Second tank body) 2.

The upper main body 1 is provided with a top wall 3 and has a bottomless cylindrical shape with an open bottom, and a horizontal partition wall 4 is provided on the top thereof, the upper side of this partition wall 4 is a buoyancy tank 5, and the lower side is an oil storage room. (Flammable liquid storage chamber) 6.

An oil supply/discharge pipe 7 with a valve for supplying and discharging oil is connected to the upper part of the storage chamber 6.

Further, a stopper 8 is provided at the lower end of the upper body 1 to prevent the lower body 2 from falling.

The upper body 1 is connected to a mooring chain 9, and its upper end slightly protrudes above the sea surface.

Note that the oil storage chamber 6 is provided with an air vent as necessary.

The lower body 2 has a bottomless cylindrical shape similar to the upper body 1, and is fitted into the oil storage chamber 6 of the upper body 1 so as to be vertically movable, thereby forming the bottom of the oil storage chamber 6.

The lower body 2 is provided with a buoyancy chamber 10 at its top, and a stopper 11 for preventing falling that corresponds to the stopper 8 of the upper body 1 on its outer peripheral surface.

One end of a large number of oil leakage prevention valve mounting members 13 is pivotally attached to the outer surface of the top wall 12 of the lower body 2, and these members 13
An annular oil leakage prevention valve 14 made of a flexible body is attached to.

As shown in FIG. 2, the inner edge of the valve 14 is watertightly attached to the top wall 12, and the outer edge projects slightly outwardly from the member 13.

Further, the top wall 12 is provided with a stopper 15 for restricting the downward movement of the member 13 and a spring 16 for urging the member 13 downward, so that the outer edge of the valve 14 is brought into close contact with the inner surface of the peripheral wall 17 of the upper body 1. The gap between the two city bodies 1 and 2 is sealed.

In the above, only oil is always filled in the storage chamber 6, and when the amount of oil in the storage chamber 6 increases, the lower body 2 is pushed down against buoyancy, and the amount of oil in the storage chamber 6 decreases. The buoyancy of the lower body 2 is then adjusted so that the lower body 2 moves upward due to the buoyancy.

Therefore, even if the amount of oil in the storage chamber 6 changes, the upper main body 1 hardly moves up and down, and furthermore, the storage chamber 6 is never filled with gas.

The shapes of the two tank bodies can be suitably shaped, and may be rectangular when viewed from above, for example.

Furthermore, as shown in FIG. 3, the bottomless rectangular parallelepiped-shaped first tank body 21 is divided into a plurality of flammable liquid storage chambers by partition walls, and the plurality of rectangular parallelepiped-shaped second tank bodies 22 are divided into a plurality of flammable liquid storage chambers. It is also possible to insert them into each.

The marine stockpiling tank according to the present invention includes a flammable liquid storage chamber 6 with an open bottom, a first tank body 1 floating on the sea surface, and a first tank body 1 that is fitted into the storage chamber 6 so as to be vertically movable for storage. a second tank body 2 forming the bottom of the chamber 6; when the amount of flammable liquid in the storage chamber 6 increases;
When the second tank body 2 is pushed down against the buoyant force and the amount of flammable liquid in the storage chamber 6 decreases, the second tank body 2 moves upward due to the buoyant force, thereby causing the storage chamber 6 to move upward. Since the tank is filled only with flammable liquid, the mounting structure will not change due to an increase or decrease in the amount of flammable liquid in the tank, and the tank will not be filled with gas.

Therefore, by setting the support to be small in advance, it is possible to reduce the wind load that the tank receives and downsize the mooring device.

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 show one embodiment of the present invention.
The figure is a vertical sectional view, FIG. 2 is a partially enlarged view of section A in FIG. 1, and FIG. 3 is a perspective view showing another embodiment of the present invention. 1.21-...Tank lower body (first tank body), 2
, 22-...tank lower body (second tank body), 6...
...Oil storage room (flammable liquid storage room).

Claims (1)

[Claims] 1 A first tank body 1.21 comprising a flammable liquid storage chamber 6 with an open bottom and floating on the sea surface, and a tank body 1.21 fitted into the storage chamber 6 so as to be movable up and down so as to open the bottom of the storage chamber 6. When the amount of flammable liquid in the storage chamber 6 increases, the second tank body 2 is pushed down against the buoyancy, and the amount of flammable liquid in the storage chamber 6 increases. When the amount of the flammable liquid decreases, the second tank body 2 moves upward due to buoyancy, thereby filling the storage chamber 6 with only the flammable liquid. .