JPS62236910A - Floating and sinking type offshore working platform - Google Patents

Abstract

PURPOSE:To keep an offshore working platform in a stable state during the floating or sinking period by making the draft of the platform smaller during the floating-up period by providing symmetrically and pivotally set ballast tanks in a vertically rocking manner to the outside of the offshore working platform. CONSTITUTION:A plurality of water-chargeable and dischargeable ballast tanks 2 are provided for an offshore working platform 1 for controlling the floating and sinking of the platform 1. The tanks 2 are symmetrically and pivotally attached through a support frame 3 to the outside of the platform 1. The tanks 2 are moved downwards in a rocking manner during the floating-up period of the platform 1 and the draft of the platform 1 is also reduced. Furthermore, during the way of floating or sinking of the platform 1, the tanks 2 are moved upwards in a rocking manner to keep the platform 1 in a stable state.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a submersible underwater work platform that is submerged to the seabed and used for various operations and investigations.

[Conventional technology]

Conventional floating underwater work platforms include those shown in Figures 5 and 6, in which ballast tanks 02, which can be filled with water, are installed on both sides of the underwater work platform 01 to control the floating and sinking of the underwater work platform 01. , 02 are provided respectively.

Therefore, when performing maintenance and inspection work on equipment on the underwater workbench 01, as shown in Fig. 5, the ballast water 03 in the ballast tank 02 (see Fig. 16)
The ballast tank 02 uses the buoyancy to make the underwater work platform 01 float above the sea surface 04. Ballast water 03 is injected into the vessel, and the underwater work platform 01 is lowered to land on the seabed.

[Problem that the invention seeks to solve]

By the way, when the underwater work platform 01 is floated above the sea surface 04 for maintenance and inspection work, etc., it is necessary to reduce the swamp A as shown in Fig. 5. In order to maintain the stability of the underwater work platform 01 while the work platform 01 is rising (see arrow B) or sinking (see arrow C), the center of the 17 points is always at the center of the underwater work platform 0.
The ballast tank 0 is positioned 1n above the center of gravity E of 1.
It is necessary to adjust the path of ballast water 03 in 2.

In order to satisfy these requirements, the conventional submersible underwater work platform must be equipped with an extremely large-capacity parast tank 02, which leads to an increase in weight.

Furthermore, if the parast tank 02 has a large capacity, when operating the underwater platform 01 submerged in shallow waters, the underwater platform 01 may slide on the seabed due to external forces such as waves and currents. In particular, the external force that the underwater work platform 01 receives from waves increases as the pressure receiving volume of the underwater work platform 01 increases, and the external force that the underwater work platform 01 receives from the tides increases.
The larger the pressure receiving area of the underwater workbench 01 is, the larger the pressure is.

The present invention aims to solve these four layer points,
By using a parast tank with the minimum necessary buoyancy, we can reduce the amount of water during ascent, maintain a sufficiently stable state during ascent and descent, and reduce the effects of external forces such as waves and currents. The purpose is to provide a submersible underwater work platform with

[Means for solving interlayer points]

For this reason, the floating underwater work platform of the present invention is equipped with a plurality of palast tanks that can be filled with water to control the floating and sinking of the underwater work platform, and these palast tanks are arranged symmetrically and vertically on the outside of the underwater work platform. It is characterized in that it is pivotably mounted so as to be swingable, and is also provided with a tank driving means that can swing the ballast F tank up and down.

[Made by Tears]

In the above-described floating underwater work platform of the present invention, when the platform floats, the plurality of palast tanks are arranged at a lower position by the tank driving means, and a certain amount of water is obtained. A plurality of paralast tanks are arranged in an upper position by the tank driving means, so that the center of buoyancy is always located above the center of gravity of the underwater platform.

〔Example〕

Hereinafter, a submersible underwater work platform as an embodiment of the present invention will be explained with reference to the drawings.
FIG. S2 is a plan view thereof, FIG. FA3 is a schematic front view showing the floating state, and FIG. 4 is a schematic front view showing the state during floating or sinking.

As shown in Figures 1 and 2, on both sides of the underwater work platform 1, there are palast tanks 2.2 that can be filled with water to control the floating and sinking of the underwater work platform 1, and are supported symmetrically. Each paralast tank 2 is fixed to the tip of the support 7 frame 3, and the base end of the support 7 frame 3 is attached to the underwater work platform 1.
By being pivotally connected to the undersea workbench 1 with a pin 4, it is provided so as to be able to swing up and down with respect to the underwater workbench 1.

Further, an eye plate 5 and a riser 9 are attached to the upper and lower parts of each pallast tank 2, respectively, and one end of a wire 6.10 is secured to each of these fibres 5 and 9.

The other end of this wire 6 is guided by an id sheep 7 and connected to a winch 8 on the underwater platform 1, while the wire 1
The other end of 0 is guided by the id sheep 11,
Wire hole 1 penetrating from the bottom to the top of the underwater work platform 1
It is connected to the winch 8 via 2.

These wires 6.10 are arranged so that when the winch 8 is operated, one side is cut off and the other side is let out.
It is connected to winch 8.

These wires 6.10, the winch 8, etc. constitute tank driving means that can vertically swing the palast tank 2, and in this embodiment, one set of such tank driving means is provided at the front and rear of each palast tank 2. Each is provided separately.

Furthermore, injecting palast water into each palast tank 2 or discharging palast water from the same palast tank 2 is performed using a pump (not shown) in the underwater work platform 1, and when discharging palast water, Compressed air is supplied from a compressed air cylinder 13 installed in the underwater workbench 1 into each paralast tank 2 via a supply pipe 14.

The submersible underwater work platform as an embodiment of the present invention is configured as described above, so that when the underwater work platform 1 floats,
By letting out the wire 6 and winding up the wire 10 with the winch 8, each ballast tank 2 is swung to a lower position and disposed as shown in Figure 1:tS3.

In this way, by adjusting the position of each ballast tank 2, the water level can be adjusted appropriately, and when performing maintenance and inspection work on the underwater work platform 1, the ballast tanks 2, 2, which have the minimum necessary buoyancy, can be used underwater. The stuttering of the workbench 1 can be sufficiently reduced.

Insects, while the underwater work platform 1 is rising or sinking,
By letting out the wire 10 and winding up the wire 6 with the winch 8, each ballast tank 2 is swung to the upper position and disposed as shown in FIG.

In this state, by adjusting the amount of ballast water in each ballast tank 2, the underwater platform 1 can float or sink, and the center of buoyancy always remains on the underwater platform 1.
Since it is located above the center of gravity of the aircraft, a sufficiently stable state is maintained during ascent and descent.

The submersible platform 1 is lowered by injecting ballast water into each ballast tank 2 using a pump (not shown), while the underwater platform 1 is floated by pumping compressed air from a compressed air cylinder 13 (supply pipe This is carried out by supplying ballast water into each ballast tank 2 through 14 and discharging the ballast water in the ballast tank 2 by a pump (not shown).

As mentioned above, in this embodiment, 11! :The ballast tanks 2, 2 with minimal buoyancy adjust the water intake and float/sink the underwater work platform 1, so the underwater work platform 1
The entire structure can be made smaller and lighter, and costs can be reduced.

In addition, since the ballast tanks 2, 2 are considerably smaller than conventional ones, the pressure receiving volume and pressure receiving area become smaller when the underwater work platform 1 sinks, and when the underwater work platform 1 is operated in shallow water, the undersea work platform 1 has the advantage of significantly reducing the influence of external forces such as waves and currents.

〔Effect of the invention〕

As described in detail above, the floating underwater work platform of the present invention is provided with a plurality of ballast tanks that can be filled with water to control the floating and sinking of the underwater work platform, and these ballast tanks are connected to each other outside the underwater work platform. A ballast tank which has the minimum required buoyancy and has an extremely simple structure in which the ballast tank is pivoted symmetrically and swingably up and down, and is provided with a tank driving means that can swing the ballast tank up and down. By using this, water can be reduced during surfacing, and a sufficiently stable state can be maintained during surfacing and sinking, making it possible to make the entire underwater workbench smaller and lighter, and significantly reducing costs.

Additionally, since the pressure receiving volume and pressure receiving area during subsidence are smaller than in the past, there is also the advantage that the influence of external forces such as waves and currents is significantly reduced.

[Brief explanation of drawings]

Figures Pt51 to 4 show a submersible underwater work platform as an embodiment of the present invention; Figure 1 is a front view thereof, Figure 2 is a plan view thereof, and Figure 3 is a schematic diagram showing its floating state. Fig. 4 is a schematic front view showing the state in the process of ascent or subsidence, Fig. 5.6 shows a conventional submersible subsea work platform, and the fjSS diagram shows its floating state. FIG. 6 is a schematic front view showing the state in the process of floating or sinking. 1. Undersea workbench, 2. Ballast tank, 3. Support frame, 4. Bin, 5. Eye plate, 6.
・Wire, 7..Guide sheave, 8..Winch, 9.
・Eye plate, 10... Wire, 11... Guide sheave, 12... Wire hole, 13... Compressed air cylinder,
14... Supply pipe.

Claims (1)

[Claims] The underwater work platform is equipped with a plurality of ballast tanks that can be filled with water to control its floating and sinking, and these ballast tanks are pivoted to each other symmetrically and vertically swingable on the outside of the underwater work platform. A submersible submersible work platform is also provided with tank drive means capable of vertically swinging the ballast tank.