JPS6387394A - Floating type petroleum production vessel - Google Patents

Abstract

PURPOSE:To obtain a floating type petroleum production vessel which can increase the capacity of an oil storage tank by the portion of the reduced ballast tank by adjusting the variation of the draft mark due to the increase and decrease of the stored oil quantity by a weight installed outside the vessel. CONSTITUTION:When an oil storage tank 4 is charged with petroleum, a hull 1 is sunk by the weight and the draft mark becomes equal to the full loading draft mark (d). A weight 10 is and onto the sea bottom 12, and the hull 1 is hot loaded. When the petroleum in the oil storage tank 4 is unloaded, the buoyancy corresponding to the weight of the petroleum acts, and the hull 1 tends to be gradually floated up, and when floating-up is started, a winch 6 is driven, and the weight 10 in continuous chain form which is connected to a pulling cable 9 is pulled up gradually, and the weight 10 and the buoyancy of the hull 1 based on the unloaded petroleum are balanced. As the load is reduced, the buoyancy is suppressed by generating the full loading state of the ballast water in a ballast tank 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an improvement in a floating oil production vessel having an oil storage tank and a ballast tank.

[Prior art]

Conventionally, floating oil production vessels have been designed to temporarily store the produced oil (oil storage tanks and a tank to prevent the ship from surfacing and becoming unstable when the oil storage tanks are empty). They had ballast tanks to hold ballast water, and these tanks were designed to serve both functions in one tank in order to maximize the tank capacity.

However, in dual-purpose tanks, residual oil in the tank mixes with ballast water and is discharged overboard, causing marine pollution. Therefore, in order to prevent this marine pollution, ships are now equipped with two separate dedicated tanks: an oil storage tank and a ballast tank. That is, the dual-purpose tank has been divided into two parts, and one part is used as an oil storage tank and the other part is used as a ballast tank.

However, this two-part system has the disadvantage that both the oil storage tank and the ballast tank have approximately half the capacity of the dual-purpose tank, resulting in a significant reduction in oil storage capacity.

In addition, if the oil storage capacity is to be maintained at the same capacity as the dual-purpose tank, a separate ballast tank with approximately the same capacity as the dual-purpose tank must be installed, which increases the size of the hull structure and reduces strength and production costs. This has the disadvantage of causing various problems.

[Purpose of the invention]

The present invention is intended to eliminate the drawbacks of the conventional floating oil production vessel, and is aimed at reducing the capacity of the ballast tank to the minimum ratio required to maintain the stanchion for safe navigation of the vessel, and reducing the capacity of the ballast tank. The purpose is to provide a floating oil production ship whose oil storage tank can be enlarged by the capacity of the ballast tank.

[Structure of the invention]

To achieve the above object, the present invention provides a floating oil production ship in which an oil storage tank and a ballast tank are submerged in water, in which a weight formed in a chain is connected to one end of a hanging device, The floating oil production ship is characterized in that the other end of the hanging device is connected to a hoisting machine installed on the ship so that it can be hoisted and twisted, so that it can be suspended underwater or on the bottom of the water. .

〔Example〕

Next, the present invention will be described in detail with reference to the drawings.

1 and 2 show a floating oil production vessel according to the present invention, with an oil storage tank 4 full of produced oil.

The hull 1 includes a submerged body 3 that is submerged in water (seawater) and an upper structure 2. The submerged body 3 is composed of left and right oil storage tanks 4.4, and a ballast tank 5.5 that connects both ends of the oil storage tanks 4, 4, respectively. The upper structure 2 has a hoist 6 and a guide roller 7 installed at each of its four corners, and correspondingly guide rollers 8 are installed at the lower four corners of the submerged body 3. The hoisting machine 6
A suspension rope 9 is wound around the suspension rope 9, and a chain-shaped weight 10 is connected to the end of the suspension rope 9 so as to be able to be wound up and twisted.

Further, mooring cables 11 (detailed illustrations are omitted) each having the other end moored to the seabed are connected to the four corners of the ship 1, so that the ship 1 is moored at a fixed position.

Furthermore, in the present invention, the ballast tank 5 has a much smaller capacity than the oil storage tank 4 because its purpose is to secure the water necessary for navigation of the hull 1.

In the floating oil production ship of the present invention having the above configuration, first, as shown in Fig. 1.2, when the oil storage tank 4 is fully loaded with oil, the hull 1 sinks due to its weight and the water swells when fully loaded. d.

At this time, all of the weights 10 land on the seabed 12 so that no load is placed on the hull 1. At this time, it is preferable to drain the ballast water in the ballast tank 5 and increase the oil storage amount accordingly.

Next, when the oil in the oil storage tank 4 is loaded, a buoyant force corresponding to the weight of the oil acts, and the hull 1 gradually tries to float, but at the same time as it starts to float, the hoisting machine 6 is activated. The chain-shaped dust 10 connected to the hanging rope 9 is gradually pulled up, and the dust 10 and the buoyancy of the hull 1 based on the loaded oil are balanced.

In the above-mentioned stanchion adjustment operation, if the buoyancy of the hull 1 is greater than the weight of the weight 10, the ship will float further, but the weight can be adjusted by lifting the dust 10 from the seabed by the required amount by hoisting the hoist 6. and ensure safe stuttering at or close to d. Further, during this operation, the guide rollers 7 and 8 prevent the sling 9 and the hull 1 from coming into direct contact and causing damage to both.

On the other hand, it is preferable that as the ballast tank 5 becomes empty, the ballast water in the ballast tank 5 is brought to a full state to suppress buoyancy as much as possible.

When the oil in the oil storage tank 4 is completely emptied by the above operation, the state shown in Fig. 3 is reached, and all the weights 10 are hoisted from the seabed and their entire weight is applied to the hull 1. The ship body 1 is maintained at approximately the same position as d, thereby maintaining the safety of the hull 1.

〔Effect of the invention〕

As described above, in the floating oil production ship according to the present invention, the weights formed in a chain are connected to one end of the lifting device, and the other end of the lifting device is connected to the hoisting machine installed on the ship. It is characterized by being able to be connected to the vessel by winding and twisting freely, and being able to be suspended underwater or on the bottom of the water.Changes in water intake caused by increases and decreases in the amount of oil stored can be adjusted using a weight attached to the outside of the vessel. Therefore, the ballast tank should have the minimum capacity necessary to secure the necessary water for navigation. Therefore, the reduced capacity of the ballast tank can be increased for the oil storage tank.

[Brief explanation of the drawing]

FIG. 1 is a side view of the floating oil carrier according to the present invention showing the oil loaded state, FIG. 2 is a plan view of the same, and FIG. 3 is a side view of the floating oil carrier of the present invention showing the boat in an empty state. 1... Hull, 2... Upper structure, 3... Submerged body,
4...Oil storage tank, 5...Ballast tank, 6...
・Hoisting machine, 7, 8... Guide roller, 9... Suspension rope,
10... Chain weight.

Claims (1)

[Claims] In a floating oil production ship with an oil storage tank and a ballast tank submerged in water, a chain of weights is connected to one end of a sling, and the other end of the sling is connected to the top of the ship. 1. A floating oil production vessel, which is connected to a hoist installed on a hoist for winding and twisting, and is capable of being suspended underwater or on the bottom of the water.