DE2500975A1 - SEA PLATFORM - Google Patents

Description

Our mark Our Ref.

B / p 80? 7

James G. Brown & Associates, Inc., ¥ 2505. Holcombe Blvd. Houston, Texas 77025, USA

Sea platform

The invention "relates to self-adhering marine platforms "or drilling rigs, as they are widely used for offshore oil drilling and oil extraction self-lifting sea platform has a main hull, whose decks accommodate cargo, machinery and personnel. At least three shafts are provided in the main hull. they are arranged horizontally and at a distance from each other. Each shaft contains an elevator. A vertical leg extends his way through every elevator to the bottom of the ocean. The elevators can move up and down the legs and thus move the platform up and down over water at a drilling site. When a sea platform is high above the surface of the water When lifted, it is exposed to the action of wind and high waves and has a tendency to tip over. Is the On the other hand, if the platform is tied up in a shipping route, it has a tendency to sink.

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Large-volume tanks are provided on the deck of the main hull. The tanks can be empty or filled with fresh water or sea water. When the tanks are flooded with water, they act as preload tanks. The combined weight of the water in all pre-load tanks lowers the platform's center of gravity and prevents the platform from tipping over, even in strong winds and waves. When the tanks are empty, i ± e serve as ballast tanks and control the center of buoyancy, which stabilizes the platform as it is towed from one deployment site to another.

The above-described sea platforms have the following disadvantages, among others: (1) After a platform is calculated and designed, the design data cannot be easily accessed used to build another platform with different dimensions. (2) The preload tanks require relative a lot of space on deck, which is desirable for the staff, the machines and the load. Because the tanks are inside the main hull are arranged on the platform, their preload and ballast effects are significantly reduced.

The present invention is intended to remedy the disadvantages outlined above.

According to the invention, a self-lifting marine platform is proposed, which has a main hull and a plurality of Has auxiliary hulls. The main vaccine is structured in such a way that he takes load, machines and accommodation rooms for the personnel. The auxiliary hulls are horizontal and spaced from each other arranged outside the main hull, but welded to it. Each auxiliary hull is watertight and is welded to a side wall of the main hull. Each auxiliary hull forms an inner shaft running in the vertical direction that accommodates an elevator. Inside, each auxiliary hull is the interior designed as a large-volume, watertight tank around the shaft. If the tank is overflowed, it serves as a preload tank. is

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the tank is empty, it can serve as a ballast tank.

The combined volume of all preload tanks in the auxiliary hulls is preferably chosen so that the tanks, when they are flooded, give the entire Y-load necessary for stability the platform is required.

In a further embodiment of the invention, the upper and The lower deck of the main runner is rectangular in shape and each side wall of the HauOtrumpfee is rectangular in top view. There are at least three auxiliary hulls connected to the port, starboard and forward ends of the main body. are welded. The rear end of the main hull creates an opening with a rectangular cross-sectional area fixed.

The invention is explained below in conjunction with the drawing using an exemplary embodiment. The. Figures show:

Figure 1 is a perspective view of a sea platform according to the present invention,

Figure 2 is a perspective view showing the position of the auxiliary hulls before they with the HpuDtrunrnf are welded,

Have been for Figure 3 is a plan view of the platform after the Hilfse c ¹ OIt> em Hauntruropf welded; Figure

Figure 4- a -Ders-nekti ^ ri see view of an auxiliary srumpfes defined animal a shaft which t elevator and qi ^ h vertically extending through don elevator leg enthfO,

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FIG. 5 shows a "preferred arrangement" in an exploded view the decks of the platform,

FIG. 6 shows the manner in which three auxiliary hulls are interconnected for the purpose of pulling them together for final assembly,

FIG. 7 shows the legs of the platform standing on the seabed, and

Figure 8 is a partial perspective view of forces acting on the components of the platform act.

The self-lifting marine platform assembly 10 according to the present invention has a main hull 11 and at least three separate ones outer auxiliary hulls 12-14- on. The auxiliary hulls are horizontally displaced from one another and preferably with the port, starboard and forward ends of the main hull welded.

According to FIGS. 1-5, the main body 11 preferably points an approximately rectangular cross-sectional area. The rear At the end of the main hull lays a rectangular opening 11 ' fixed. The essential, the stress-absorbing components are the longitudinal bulkheads 40 and the transverse bulkheads 41. The Bulkheads divide the main hull into rectangular units. A typical main hull has a main deck 50 upper quarters deck 51> an engine deck and a lower quarters deck 52 and a floor deck 53. The main body 11 needs no longer to contain inner preload tanks. Accordingly, the entire space within the main body 11 can now be used Used to accommodate cargo, machinery and accommodation.

The platform assembly 10 is shown in Figure 1 for offshore oil drilling and extraction. For this purpose, the platform has

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moderately the following facilities; A helipad 18, a derrick 19 »hoists 20, material separation systems 21» 22,; a support crane 25, a rescue capsule 2A, a floor hatch 25, an anchor winch 26, a line boom assembly 27, a slide rail arrangement 28, a fresh water tunnel 29, an anchor frame 30 and a caterpillar 31. .

When the platform 10 is raised on legs 17 that are shown in the sea floor 33 (Figure 7) are embedded, the most important stresses are the bending moments 34 and the shear forces. (Figure 8). A general strain analysis can be found in either mathematical equations or preferably in programs for computers. Since the main body 11 is in rectangular shape Subunits can be subdivided, and since the main body Furthermore, it is no longer needed to accommodate Yorlast tanks, the setting up of such computer programs is essential - licb through the simplified structural design of the platform arrangement 10 facilitated according to the present invention.

After a construction for the platform 10 has been laid out is, either in equation form or in the form of a computer program, platforms of different length dimensions and load-bearing properties can be constructed relatively simply. Construction plans can also be a Platform in a simple way for another platform with. different dimensions can be modified. The modified plans are so complete and usable that with you can make estimates of the cost and time required for construction. : ..

Each of the auxiliary hulls 12-14 forms a shaft 15 »of the one Contains elevator 16, which is suitable for receiving a leg 17. The platform 10 can move in the vertical direction the legs 17 are moved. Since neither the elevator 16 nor the Legs 17 are the subject of the present invention, these parts are not explained in more detail. In the patent literature,

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different types of such lifts and legs. .1.7 _{"Loading: written,} ...., ··.....

According to one of the essential features of the present invention, each of the auxiliary hulls forms around the shaft. 15 a large-volume tank, which serves as a pre-load tank. when. the platform is raised above the surface of the water, and which can be used as a ballast tank when the platform is anchored in the sea. The auxiliary hulls 12-14 are shown to have preload tanks 12 ^! -14 · included. > .......

The cross-sectional area of each Hilfsrumpfes.ist _{trapezoidal,:} although they may also be formed semi-circular or may have einen.oeliebigen cross section between trapezoidal and circular. For example, it can be hyperbolic and parabolic. However, a trapezoidal cross-sectional area is the easiest to design and construct. , Each auxiliary hull preferably has longitudinal and transverse bulkheads 42 und43 on (Figure 3), in particular, each auxiliary hull the same height as the main body .11, so that the side walls of each Hilfsrunrofes completely between the main deck 50 and _the. .Bodendeck 53 < This main body 11 extend.

According to a further essential feature of the present invention, the main hull 11 and auxiliary hulls 12-14 are constructed and welded to one another in such a way that they are always watertight independently of one another. Accordingly, the main and auxiliary bodies can be prepared in the _wide-1 in different yards at different locations. For example, the auxiliary hulls 12-14 with their elevators 15 can expediently be manufactured in a shipyard with greater construction experience, while the main hull 11 can be manufactured by another shipyard with less experience, for example in another country. Such a "versatility in the choice of the place of manufacture makes it possible to have favorable economic conditions

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and take advantage of lower labor costs, thereby reducing overall costs in the manufacture of the entire platform assembly

10 can be reduced considerably. After the main body

11 and the auxiliary hulls 12-14- have been manufactured separately are (they can of course also be produced in a verft are), they can be connected to each other by connecting links 32 (Fig. 6) and towed into a shipyard in which the platform 11 is fully assembled.

Before welding the auxiliary hulls to the main hull

they dressed the edges of the auxiliary hulls so that / in alignment stand with the walls of the main hull. Even after the main hull and auxiliary hulls are welded together, everyone makes Auxiliary hull still has a watertight tank around its Shaft 15.

The volume capacity of each tank in each auxiliary hull is sufficiently large so that a sufficient preload on the associated leg 17 is achieved. The common volume of all tanks 12 '- 14 ·' is sufficient if the tanks are filled with water be flooded so that the platform assembly 10 withstands maximum moments and shear forces on the platform can act, and which are generated by the combined action of wind and waves. As a result, additional, smaller preload tanks within the main hull can be completely dispensed with in the case of the present invention.

Another essential advantage of the present invention is to be seen in the fact that the preload tanks 12 '- 14-' are complete lie outside the main hull and this gives the tanks far better control of the center of gravity of the platform and the buoyancy can be achieved than would be the case if the preload tanks were arranged within the main hull 11, as is the case with conventional platforms.

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Claims (3)

Β / ρ 8037 -8- January 8, 75 patents Proverbs 1. Self-lifting seas? Pü att form an order for oil wells with a main hull to accommodate cargo, machines and accommodation for the crew above the water level for offshore (offshore) wells, characterized in that the platform has a number "of horizontal , at a distance staggered auxiliary hulls (12, 1J, 14), the leather of which is arranged completely outside the main hull (11) and welded to these, that each auxiliary hull (12, 15-14-) has sufficiently large cross-sectional dimensions that therein a vertically extending shaft (15) and a large-volume watertight tank (12J 13J 14 ') can be found around the shaft (15), wherein each tank (12', 13 ', 14') can be filled with water or empty that , each shaft (15) has an elevator (16) which movably receives a leg (17) extending vertically to the seabed, and wherein the platform can be moved vertically up and down on the legs (17), and that all tanks (12 ¹ , 13 ^r , 14 ¹ ) when full in all auxiliary hulls (12, 13? 14) have a common volume sufficient to provide the desired preload on the platform when the platform is raised completely above water. 2. Sea platform arrangement according to claim 1, characterized in that that the main hull (11) has a plurality of decks (50-53), the upper and lower decks of the Main hull are rectangular, and that the Side walls between the decks are also rectangular. 3. Sea splattform arrangement according to claims 1 and 2, thereby characterized in that three auxiliary hulls (12, 13 »14) are provided are, one with the port end, the second 509830/0676 Β / ρ 8037 -9- 8.1.75 with the starboard end and their third with the front on The end of the main body (11) is welded. 509830/06 76 , ⁱ⁰ ■ Blank page