DE2218775A1 - Floating drilling platform or similar floating arrangement - Google Patents

Description

Patent attorneys Dipl.-Ing. F. Weickmann,

Dipl.-Ing * H.Weickmann, Dipl.-Phys. Dr-K. Fincke Dipl.-Ing. F. ä / Weickmann, Dipl ^ -Chem * B. Huber

8 MUNICH 86, POST BOX 860 820

MÖHLSTRASSE 22, CALL NUMBER 48 3921/22

<98 3921/22>

INGENIEURSBÜKSAU IiARCON (MARINE CONSULTANTS) "N.V., The Hague / Holland

SCHEEPSBOUWBSLAHGEM N.V., The Hague / Holland

Floating drilling platform or similar floating one arrangement

The invention relates to a floating drilling rig or drilling platform or a similar floating arrangement with more than three vertical columns extending down from the platform extend from and are rigidly connected to this, the columns at their lower ends floating bodies with facilities for submerging the floats by filling them with water, and with a central connection arrangement between, the pillars from which struts extend to the upper and lower points of the pillars, with the centerlines of the struts converging at approximately a single point and no connecting means for each of the several struts in the vertical side surfaces of the platform by adjacent ones Pillars are provided.

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Such floating arrangements are known, for example, from US Pat. No. 3,507,239 and the corresponding British Pat. No. 1,211,091. In these publications an arrangement is shown in which the central connection of the struts is at an appreciable distance below the working deck of the platform and preferably at the level of the upper edge of the floating body and thus at the lower End of the pillars is provided. Substantially horizontal and inclined struts extend from this point towards lower and upper points of the pillars. In the deck structure, a second, secondary connection can be provided through a substantially vertical strut is connected to the first link and from which only deck beams to the pillars go out.

It has been shown that this structure, despite considerable advantages, can be improved with regard to the management of the Forces and loads and the influence of water and waves.

To achieve such an improvement, the arrangement of the initially mentioned type according to the invention characterized in that the central connecting arrangement is essentially in the Height of the deck of the platform is provided, and that of this connecting arrangement substantially horizontal struts to the Pillars back and forth inclined struts downward, each without interruption to the lower end of a pillar get lost.

This has the following advantages compared to the known one Construction.

When towing, the floating bodies of the floating arrangement float generally on the water and only partially submerged, and in this condition the known arrangement becomes significant Influences of the waves on the connecting arrangement exposed to its low height between the columns, as this Connection arrangement should have significant dimensions. Using the invention this is avoided and therefore it is in bad weather it is possible to continue towing, while

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rend the connection arrangement is high above the water. It is therefore not necessary to ballast the float assembly so early that it can be towed further in is reduced to a considerable extent, with the partial lowered position results in a significantly higher drag resistance. ■

Furthermore, if the float assembly is partially lowered, so for example in very bad weather while towing and always when the platform is in a stationary position for normal Use, such as located in drilling, is the influence of the Waves less as they close the link assembly near the Can't reach working decks · Zwai? become the forces $ which are exerted by the waves on the columns, partially transferred to the connecting arrangement, but only indirectly over the struts and therefore dampened so that they only act on the connecting assembly after it has been reduced and shocks are balanced.

The inclined struts extending from the connecting arrangement according to the invention to the lower points of the pillars, carry the loads from the working deck in the middle area between the columns with the entire heavy structure on them, such as the drilling rigs, directly from the connection arrangement in the vicinity of the floating body and thus to the swimming surface the arrangement, so that the load on the pillars is significantly reduced. These struts are under pressure, so that a possible buckling or bowing should be expected, but it is easy to do so in this regard strong enough without them becoming heavy and bulky. Furthermore, a connection arrangement at a greater height in the Close to the deck can be easily controlled and maintained during long periods of work at sea. This is with a connection arrangement at a low altitude easily reached by the waves, impossible or much more difficult. Therefore, it is it is also possible to better protect the connection arrangement against corrosion at a greater height.

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In a preferred, further embodiment of the invention the arrangement mentioned at the outset is characterized in that it essentially has a second central connecting arrangement has perpendicularly below the central main connection arrangement, which second central connection arrangement has only a connection with the struts that are in the essentially horizontal to one lower end of each column extend, wherein the second connection arrangement by a substantially perpendicular strut with the central connection arrangement connected near the deck. This second connection arrangement is used in this way only for the horizontal Connection between the lower ends of the columns and therefore does not have to transmit very high forces, while only one small number of struts must be connected by it, so that it is possible to use this second connection arrangement with small Dimensions and light weight to manufacture, the small dimensions of the influence of the waves on the connection arrangement appear negligible.

An arrangement according to the invention is preferably also characterized characterized in that the central connection arrangement in the vicinity of the deck as a connection core with connections for the essentially horizontal struts and with downwardly inclined, essentially prism-shaped or truncated pyramid-shaped Parts is formed directly or via connected transition pieces that are inclined from these parts extend, or are connected to both devices in an extension of the parts with struts, the struts a smaller Have cross-sectional area than the projecting parts at their end that are furthest away from the struts and therefore lie closer to the connection arrangement.

In some cases, however, another embodiment is the Connection arrangement preferred, which is made possible in that the connection arrangement is raised and not through Water and waves is affected, and the many advantages for a better support of the working deck and those on it heavy parts such as a derrick etc. over a

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has a large area. This further embodiment is thereby characterized in that the central connection arrangement in near the deck as a horizontal box or an annular, hollow beam with a substantially rectangular one Cross-section is formed.

This annular box or hollow beam can be in a horizontal The plane may be circular, but is preferably polygonal in shape in the horizontal plane, preferably with straight areas without kinks between the points where the struts connect to the polygonal box. As a result, the forces are transmitted in the most favorable way between the hollow beam or the box and the struts.

If, as indicated above, a second central connection arrangement is used at a lower height, it is in the case of the use of an upper, central main connection arrangement in Form of an annular, hollow beam or box. In the vicinity of the working deck advantageous, the vertical connection between to form the two connection arrangements as one or more struts, which if desired in a slightly inclined Direction from the lower surface of the hollow beam or box near the deck to the secondary connection assembly.

In the following, for example, preferred embodiments of the invention are explained in more detail with reference to the accompanying drawings.

Fig. 1 is a side view of the arrangement according to the invention in the form of a floating drilling platform;

Fig. 2 is a plan view of this platform;

Fig. 3 shows a vertical section of the central area the platform essentially along the line HI-III in Figure 2;

Figure 4 is a side view of another embodiment the drilling platform according to the invention;

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S ¹ Ig. Figure 5 is a top plan view of the ilitt of the Pig construction. 4;

Pig. 6 shows a section of part of the arrangement of FIG Pig. 4 and 5 in a vertical plane along the line VI-VI in Pig. 5.

The floating platforms shown in the drawing derive their buoyancy essentially from five floating bodies 1 with a circular cross-section, the ^ e via conical transition pieces 2 are connected to a column 3 which extends upwards and has the same axis as the floating body 1. The pillars and the floating bodies are arranged at the corners of a horizontal, equilateral pentagon.

The columns 3 can extend down into the floating body 1 and be connected to their flat bottom surface, see above that in the floating bodies a suitable annular space for receiving ballast around the lower extent of the columns arises.

At the upper ends of this arrangement a deck structure 5 is provided, which is not shown in detail and its contours by dashed and dot-dash lines in Pig. 2 between the horizontal cover struts 16 and 20 are indicated, which are to be described later. This structure can be one or comprise several decks in a manner known per se. A floating oil rig or drilling platform often has three decks, that is, a machine room deoc, a material and tool storage deck and a residence declc provided. At 6 in Pig. a derrick can be attached and at 7 a higher one can be installed Deck are located, which can protrude outward if desired over the arrangement and a landing platform for helicopters can form.

According to Pig. 1, 2 and 3 is a central connection arrangement 8 provided, which geometrically consists of a central, prismatic core 9 with a vertical axis. This core is

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pol3 ^r gonal, go that each of its side surfaces is perpendicular to the axis of the struts 16, which extend horizontally to one of the columns 3. In the embodiment shown, in which the columns are attached to the corners of an equilateral pentagon, the core 9 is also an equilateral pentagon in a horizontal section and in a plan view from above. '

Each vertical interface of the core 9 is two protruding 'Jeile 10 and 11, which merge vertically into each other and the form a one-piece assembly and have a common perpendicular interface 12. The core 9 does not have to be a separate part with its own closed, vertical side surfaces, but can be a unit with the parts 10 and 11 form, which is mainly open and hollow inside, but inside reinforcement struts and plates or the like exhibit. These reinforcements can be formed by plates which are welded inside the core and transfer the forces in the desired directions. In addition, can an external reinforcement between the surfaces 12 may be provided. As can be seen from FIG. 2, two perpendicular boundary surfaces 12 each time extend in parallel from the center point of the connection to the outside, but it is also possible to let the surfaces converge a little on the outside. The upper interfaces 13 and the lower interfaces of the protruding parts 11 are also parallel, however, these can also. Areas if desired converge slightly on the outside, so that the projecting parts 11 have a truncated pyramid shape. The upper interfaces 13 and the lower boundary surfaces can also have a different internal angle than the vertical side surfaces 12 The end face 15 of the projecting part 11 has the transverse shape of an even polygon, in this lalle of a square.

Right-angled, horizontal struts 16 extend horizontally along the lower surface of the deck from the protruding ones Parts 10 to the pillars 5. The inclined struts 22 extend nit a circular or other round cross-section from the projecting parts 11 and in their

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Axis down to the lower ends of the pillars. For a good Connection of the projecting parts 11 with the struts 22 goes each side of the square end face of the rope 11 into one flat surface 17, which ends at 18 in the strut 22 with a round or circular cross-section, and between the four flat surfaces 17 are four conical surfaces 14 on each projecting part 11 is provided. In this case the conical surfaces (form parts of cones with inclined axes and with circular base, provided that the struts 22 have a circular cross-section, each of their apex in a Corner of the square at the end of the protruding rope 11. The flat surfaces 17 and the conical surfaces 14 are straight Boundary lines between one another so that the surfaces 17 represent triangles. This enables easy production and welding, since the plates that make up this structure have no boundary lines in the form of curved conic sections.

The struts 22 go in the vicinity of the columns 3 over transition areas 23, which are formed similar to the surfaces 14 »17 and four flat surfaces similar to surfaces 17 and four curved surfaces similar to surfaces 14 on iron, essentially prismatic or pyramidal cables 24, by means of which they are each connected to their columns 3. Of the four interfaces of the parts 24, the two perpendicular surfaces can be parallel to one another, and so can the upper and lower surfaces be parallel, so that prismatic connecting parts 24 arise. If desired, however, it is also possible that two of the opposite surfaces or both pairs of surfaces diverge and a truncated pyramidal rope or the like form, which is connected to the column via a cross-section that is larger than the cross-section at the transition into the struts 22 is due to the alternating flat and curved surfaces.

From Fig. 2 it can be seen that the struts 19 and 20 in the same horizontal plane as the struts 16 connect the columns 3 with each other. In Fig. 1, the front strut 19 is in the middle The rope is shown interrupted so that the connection 8 can be seen. The struts 20 are right-angled, like the struts

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16, and the three struts 19 are circular in cross section with approximately truncated prism-shaped transition parts 21 on the columns, the upper surface of which is horizontal and the two protruding lateral ones Flats are perpendicular, while the lower surface is extends downward to the column as shown in FIG. These transition parts .21 go over in the circumferential direction alternating.) triangular flat and inclined conical plates at 28 in the struts 19 over. In the vicinity of the transition between the conical transition pieces 2 and the columns 3 is also each time in each plane through the axes of the two adjacent Pillars a strut 26 is provided which extends horizontally between the adjacent pillars, and a strut 27> in the same vertical plane through the two adjacent pillars 3 and upwards in the vicinity of a horizontal strut 19 »20 in the upper area of the structure runs. All of these struts preferably have a circular cross-section and are essentially prismatic at both ends or pyramidal transition parts 30, which have four levels Faces and intervening four conical faces at 29 in the circular struts 26, 27 pass over.

Ton the lower surface of the prismatic core 9 of the compound extends from a circular strut 31 perpendicular to below. This strut goes at the upper and lower ends over a transition part 32, which also alternates between a flat and has a curved surface, on the one hand in the core 9 and on the other hand in a connection 33, which is also pentagonal and is prismatic in shape and merges via connecting parts 34, 35 into five horizontal struts j36_ each in a column. This lower connection has essentially the same shape in plan view as the connection 8 (see FIG. 1) but much simpler, since no inclined struts are connected to it, so that, as can be seen from Fig. 1, is designed much lower in the vertical cross-section and thus offers significantly less water resistance. The transition parts 32 of course don't have four each, but rather five triangular faces interrupted by five conical faces v / er den-.

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All struts are hollow with the necessary reinforcements if desired inside, v / ie with plates, ribs or sheet parts.

In the pig. 4 »5 and 6 an embodiment is shown in which the central connection according to ELg. 1 and 2 by an annular Body 36 is replaced, which is composed of flat plates to form a hollow beam. As can be seen from Fig. 5, this body 36 is essentially pentagonal with parts 37 at the connection points to the struts 16 and 22, and thus at the corners of the pentagon, which are perpendicular to the Uinkeliialierungen of the five corners of the pentagon so that the pentagon is flattened in these corners and thus an irregular decagon is created.

In this way the forces in these corners are favorably between the struts and the annular, hollow body 56 transferred.

The struts 22 have connecting parts 38 opposite the hollow body 36, which are also the connecting parts for the struts 16 are. In this way, the axes of the inclined struts 22 do not intersect at the intersection of the axis of the horizontal Striving 22, as in the previous embodiment, but above deck 5.

This structure facilitates the support of the deck structure, as it now covers a large area and is very effective due to the hollow body 36 is supported.

In this case a strut 39 extends from the hollow Body 36 in an averted, but somewhat inclined, direction to the simple, lower connection 40. The struts 39 go, as can be seen from FIG. 4, into the annular hollow body 36 in a straight portion in the lower surface thereof between two parts 37 over. This strut 39 has essentially the same transitions with alternating flat and curved Areas, which are designated here by 41, to the prismatic connecting parts 42 at the ends, through which they at their upper

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End n to the hollow body 36 and connected at its lower end to the connection 40. The struts 16 and 22 could also be in the hollow body 36 dm ^s eh pass horizontally inclined connecting portions so that they are in the area 36 as the hollow body is substantially wider in the area of the strut. In this case, the struts are preferably not connected to the corners of the pentagonal, hollow body, but to the central areas of its sides.

The hollow body 36 may be replaced v / ground, the upper and lower in its horizontal surface is fully closed by a hollow box with the same outer ~ I ^p orm.

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Claims (8)

P a t e η t a η G ρ r ii c Ii e 1. Floating Lohr platform or similar arrangement nothing more as three vertical Säuion, which extend downward from one Extend the platform and are rigidly connected to it, the columns with floating bodies at their lower ends with devices for lowering the floating body by Millon Have water, and with a: *? central connection arrangement wipe the pillars, from the struts to the top and bottom Point of the pillars emanate, their center lines roughly in a Point together and without connections for the various struts that are in the vertical side faces of the platform, which run through adjacent columns, provided are characterized by » that the central connection arrangement (8, 36) approximately in de :. ' Height of the decks of the platform is provided, and that of this Connecting arrangement (8, 36) essentially horizontal struts (16) with columns (3) and, moreover, downwards inclined struts (22) without interruption to the lower linden of the columns (3) run. 2. Floating drilling platform according to claim 1, characterized characterized in that a second central connection arrangement ^ 33.40 JLm essentially vertical below the first central connection arrangement (8, 36) is provided, the second central connection arrangement (33> 40) including a connection with the struts (43) j which si ~ jh essentially horizontally; each one below:.: en End of each column (3) extending, and wherein the second connecting arrangement 33,40) through a substantially vertical strut (31, 39) with the central connecting arrangement (ü, 36) near the deck. 3. Floating drilling platform according to claim 1 or 2, d a through characterized in that the central connection arrangement (8, 36) in the italia of the deck as a fore 209847/0695 binding core (9) with parts (10) for the essentially horizontal struts (16) and downwardly inclined, substantially prismatic or truncated pyramidal parts (11) is formed, which extend directly or via transition parts that extend from these parts (10, 11), and are beveled from these, or connected via both devices to the struts (16, 22) in their direction are, these struts (16, 22) have a smaller.quetzalsfläche than the protruding parts (10, 11) on their Have ends * facing away from the struts (16, 22) and so closer to the connecting arrangement (8, 36) » 4. Floating drilling platform according to claim 1 or 2 ,. there - characterized by that the central Connection arrangement near the basin as a horizontal one Box or annular, hollow body (36) with essentially rectangular, perpendicular cross-section is formed. 5. Floating drilling platform according to claim 4 »d a d u r c h ' characterized in that the annular body or Box (36) straight outer wall parts between the joints the struts (16) and thus essentially forms a "pentagon" in the horizontal plane. 6. Floating drilling platform according to claim 2 and one that Claims 4 and 5, characterized in that that the substantially vertical strut between the two connecting arrangements (36, 40) consists of one or more Strut (39) consists, if desired, in a slightly inclined! Direction from the lower surface of the hollow Body (36) near the deck to the secondary connection assembly (40) extend. 7. Floating drilling platform according to claim 2 and one of the claims 3 to 6, characterized in that the second connection arrangement. (40) in the lesser Height a connection with a number of essentially 209847/0695 horizontal prismatic or pyramidal 'jeilon' includes, each aligned with a substantially horizontal strut (43), as well as a or nolreere upward, essentially prismatic or has truncated pyramidal parts (42), "each for one the essentially vertical struts (31 »59) on the connection with the central connection arrangement (8, 36) are provided in the vicinity of the deck. 8. Floating drilling platform according to one of the preceding Claims, characterized in that essentially the downward and oblique downward from de: .- central Connection measuring arrangement (8, 56) made of aligned struts (51> 59) have an essentially circular cross-section, and that the transition parts between the connecting arrangement (8, 56) and the struts (22, 51,;> 9) each through as many flat planes (17> 52, 41) are formed as the adjoining, preliminary: -? ing ropes (11, 52, 42) dex 'connection arrangement have, the flat surfaces alternating in the circumferential direction with parts of the conical surface. 209347/0695 bath ns Blank page