U-shaped counterweight structure for deepwater dynamic cable laying

Abstract

The present invention discloses a U-shaped counterweight structure for laying deepwater dynamic pipes and cables, comprising a counterweight body and a lifting lug assembly arranged on the counterweight body; the counterweight body is provided with a through groove penetrating the first surface and the second surface opposite thereto, and the through groove also penetrates the third surface of the adjacent counterweight body, forming a U-shaped groove for the dynamic flexible pipe and cable to fit therein. The U-shaped counterweight structure for laying deepwater dynamic pipes and cables of the present invention has a simple structure, provides counterweight for the dynamic flexible pipe and cable, and can prevent the dynamic flexible pipe and cable from being damaged by the counterweight structure, solves the interference problem between the dynamic flexible pipe and cable and the operating vessel during the vertical laying process, and assists the connection of the dynamic flexible pipe and cable to the anchor foundation.

Description

Technical Field

[0001] The invention relates to the technical field of marine engineering, and in particular to a U-shaped counterweight structure for laying deep-water dynamic pipes and cables. Background Art

[0002] In the development of deepwater offshore oil, dynamic flexible risers are widely used to connect submarine oil and gas pipelines back to FPSO tankers. Wave configuration is one of the common configurations of dynamic flexible risers. During the vertical laying process of the floating section of the wave-configuration dynamic flexible riser, the float makes the riser float, which makes it easy for the riser to interfere with the bottom of the ship or the moon pool of the ship, and it will also be difficult to connect the riser to the anchor foundation near the seabed.

[0003] Regarding the above-mentioned riser laying problem, the traditional approach is to hang a counterweight on the riser. However, the hanging of the counterweight causes a collision problem with the riser, which is also a problem that urgently needs to be solved. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a U-shaped counterweight structure for laying deep-water dynamic umbilical cables, which can avoid collision with dynamic flexible umbilical cables.

[0005] The technical solution adopted by the present invention to solve the technical problem is: to provide a U-shaped counterweight structure for deepwater dynamic pipe and cable laying, comprising a counterweight body and a lifting lug assembly arranged on the counterweight body;

[0006] The counterweight body is provided with a through slot penetrating the first and second opposite surfaces thereof, and the through slot also penetrates the adjacent third surface of the counterweight body to form a U-shaped slot for the dynamic flexible pipe cable to fit therein.

[0007] Preferably, the inner surface of the U-shaped groove is a smooth surface, and the junction between the U-shaped groove and the surface of the counterweight body is chamfered to form a transitionally smooth connection.

[0008] Preferably, the U-shaped groove includes a first U-shaped segment penetrating the first surface, and a second U-shaped segment axially connected to the first U-shaped segment and penetrating the second surface; the first U-shaped segment is trumpet-shaped.

[0009] Preferably, all edges and all vertices of the counterweight body are rounded to form rounded transitions.

[0010] Preferably, the eye assembly comprises at least one first suspension eye, and the first suspension eye is arranged on the first surface of the counterweight body.

[0011] Preferably, there are four first hanging ears, which are arranged in a U-shape on the first surface.

[0012] Preferably, the eye assembly further comprises at least one second hanging eye, and the second hanging eye is arranged on the second surface of the counterweight body.

[0013] Preferably, there are four second hanging ears, which are arranged in a U-shape on the second surface.

[0014] Preferably, the lifting eye assembly further comprises at least one lifting eye, which is arranged on a fourth surface of the counterweight body opposite to the third surface.

[0015] Preferably, one lifting lug is provided, and when the U-shaped counterweight structure is lifted and lowered by means of the lifting lug, the lifting lug is located directly above the center of gravity of the U-shaped counterweight structure.

[0016] The U-shaped counterweight structure of the present invention has a simple structure, provides counterweight for the dynamic flexible pipe and cable, and can prevent the dynamic flexible pipe and cable from being damaged by the counterweight structure; solves the interference problem between the dynamic flexible pipe and cable and the operating vessel during the vertical laying process, and can also assist in the connection of the dynamic flexible pipe and cable to the riser anchor foundation. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0018] Figure 1 is a schematic structural diagram of a U-shaped counterweight structure in one direction according to an embodiment of the present invention;

[0019] Figure 2 is a schematic structural diagram of a U-shaped counterweight structure in another direction according to an embodiment of the present invention;

[0020] Figure 3 It is a schematic diagram of the suspension state of a U-shaped counterweight structure according to an embodiment of the present invention;. DETAILED DESCRIPTION

[0021] In order to have a clearer understanding of the technical features, purposes and effects of the present invention, specific embodiments of the present invention are now described in detail with reference to the accompanying drawings.

[0022] like Figure 1 , 2 As shown, a U-shaped counterweight structure for deepwater dynamic umbilical cable laying according to an embodiment of the present invention includes a counterweight body 10 and a lifting lug assembly arranged on the counterweight body 10 .

[0023] The counterweight body 10 is a polyhedral structure. Figure 1 The rectangular parallelepiped structure shown can also be a semicircular structure. All edges and vertices of the counterweight body 10 are rounded to form a rounded transition to prevent sharp edges or sharp angles from colliding with the dynamic flexible pipe cable.

[0024] The counterweight body 10 is provided with a through groove that penetrates the first surface 11 and the second surface 12 opposite thereto, and the through groove also penetrates the third surface 13 of the adjacent counterweight body 10, forming a U-shaped groove 20 for the dynamic flexible umbilical cable to fit therein. The inner size of the U-shaped groove 20 is larger than the diameter of the dynamic flexible umbilical cable. After the counterweight body 10 is hung on the dynamic flexible umbilical cable, the U-shaped groove 20 can surround the dynamic flexible umbilical cable, so that the entire U-shaped counterweight structure can be hung and fitted on the outer periphery of the dynamic flexible umbilical cable. The dynamic flexible umbilical cable includes but is not limited to a hose (such as a flexible riser), an umbilical cable and a submarine cable.

[0025] The inner surface of the U-shaped groove 20 is smoothed to form a smooth surface, which will not scratch the outer peripheral surface of the dynamic flexible pipe cable. In addition, the U-shaped groove 20 and the surface of the counterweight body 10 are chamfered to form a transitional smooth connection to prevent sharp edges or sharp angles from colliding with the dynamic flexible pipe cable.

[0026] Structurally, the U-shaped groove 20 may include a first U-shaped segment 21 and a second U-shaped segment 22 connected axially. The first U-shaped segment 21 penetrates the first surface 11 of the counterweight body 10, and the second U-shaped segment 22 penetrates the second surface 12 of the counterweight body 10. The first U-shaped segment 21 is widened to form a trumpet shape, with the end with a smaller diameter connected to the second U-shaped segment 22, and the end with a larger diameter connected to and penetrating the first surface 11. The trumpet-shaped setting of the first U-shaped segment 21 increases the gap between its inner surface and the dynamic flexible pipe and cable, so that the dynamic flexible pipe and cable can have a certain gap in the U-shaped groove 20 to tilt.

[0027] The eye assembly comprises at least one first suspension eye 31, which is disposed on the first surface 11 of the counterweight body 10 and is used to be connected with a suspension rigging to suspend the U-shaped counterweight structure on the dynamic flexible umbilical cable.

[0028] In this embodiment, four first suspension lugs 31 are provided, arranged in a square shape on the first surface 11, so that the heel and pitch posture of the U-shaped counterweight structure can be easily controlled by the suspension rigging, and the heel and pitch movement amplitude of the U-shaped counterweight structure can be reduced. After the U-shaped counterweight structure is suspended on the dynamic flexible pipe cable, the center of gravity of the four first suspension lugs 31 is located directly above the center of gravity of the counterweight body 10.

[0029] The eye assembly also includes at least one second hanging eye 32, which is arranged on the second surface 12 of the counterweight body 10. After the U-shaped counterweight structure is hung on the dynamic flexible pipe cable, another counterweight structure can be hung below through the second hanging eye 32 to form a counterweight series connection, increase the counterweight tonnage, and solve the problem of overloading the laying system due to hanging a large counterweight at a time. The counterweight structure suspended below the U-shaped counterweight structure can be another U-shaped counterweight structure or a conventional counterweight structure used in the prior art.

[0030] Similar to the arrangement of the first hanging ears 31 , four second hanging ears 32 are provided and arranged in a square shape on the second surface 12 .

[0031] The lifting lug assembly also includes at least one lifting lug 33, which is disposed on the fourth surface 14 of the counterweight body 10, and the fourth surface 14 is opposite to the third surface 13. The lifting lug 33 is used to connect with the lifting rigging to realize the lifting of the U-shaped counterweight structure during the lifting into the water, transfer, and transportation. When transferring or storing the U-shaped counterweight structure, the U-shaped counterweight structure is lifted or lowered after being connected to the lifting lug 33 by the lifting rigging. When lowering the U-shaped counterweight structure, its third surface 13 is placed downward on a supporting surface such as a ship deck or the ground. The third surface 13 passes through the U-shaped groove 20 to form two surfaces located on both sides of the U-shaped groove 20, and the two surfaces are preferably located in the same plane to ensure the stable placement of the U-shaped counterweight structure.

[0032] like Figure 2 As shown, in this embodiment, one lifting lug 33 is provided, which is conducive to simplifying the lifting rigging of the U-shaped counterweight structure. When the U-shaped counterweight structure is lifted and lowered by the lifting lug 33, the lifting lug 33 is located directly above the center of gravity of the U-shaped counterweight structure.

[0033] The U-shaped counterweight structure of the present invention is suitable for vertical and horizontal laying of dynamic flexible pipe cables in deep water.

[0034] The following description will be made by taking the example of suspending the U-shaped counterweight structure of the present invention on a vertically laid dynamic flexible riser.

[0035] refer to Figure 1-3 The method of hanging the U-shaped counterweight structure on the dynamic flexible riser is as follows:

[0036] On the ship deck, two sets of suspension rigging 100 are connected to the first suspension lugs 31 of the U-shaped counterweight structure, one set of suspension rigging 100 is connected to the two first suspension lugs 31 on the same side, and the other set of suspension rigging 100 is connected to the other two first suspension lugs 31 on the same side. The lifting rigging is connected to the lifting lugs 33 of the U-shaped counterweight structure, and the U-shaped counterweight structure is lifted and lowered into the water by connecting the lifting rigging with a crane.

[0037] When the U-shaped counterweight structure is lowered to the same water depth as the dynamic flexible riser pull-down card (such as 80 meters or 160 meters in water depth), the crane starts active heave compensation, and the ROV grabs the long-handled ROV hook of the suspension rigging 100 on the U-shaped counterweight structure and connects it to the rigging on the pull-down card; two sets of suspension rigging 100 are respectively connected to the rigging on both sides of the pull-down card, and ensure that the U-shaped groove 20 on the U-shaped counterweight structure faces the dynamic flexible riser.

[0038] After the connection of the suspension rigging 100 is completed, the crane continues to lower the U-shaped counterweight structure. When the weight of the U-shaped counterweight structure has been completely transferred to the pull-down card of the dynamic flexible riser, the crane hook continues to be lowered until the hook is lowered to the water depth where the U-shaped counterweight is located, and the lifting rigging of the U-shaped counterweight structure is relaxed. The ROV releases the lifting rigging from the U-shaped counterweight structure and connects the long-handled ROV hook on the lifting rigging to the lifting rigging, so that the lifting rigging is doubled and shortened. Then, the crane recovers the lifting rigging to the deck.

[0039] When one or more counterweight structures (U-shaped counterweight structures or conventional counterweight structures) need to be connected in series below the above-mentioned U-shaped counterweight structure, after the suspension rigging 100 on the U-shaped counterweight structure is connected to the rigging on both sides of the pull-down card, another suspension rigging is connected to the second suspension lug 32 below the U-shaped counterweight structure. The counterweight structure is lowered to the same water depth as the above-mentioned U-shaped counterweight structure, and the suspension rigging on the counterweight structure to be lowered subsequently is connected to the suspension rigging on the second suspension lug of the U-shaped counterweight structure. The specific operation is similar and can refer to the above-mentioned operation.

[0040] Monkey fists can be tied to the long-handled ROV hooks of the above-mentioned hanging rigging and lifting rigging, respectively, so that the ROV can grab the rigging or the long-handled ROV hook by grabbing the monkey fists.

[0041] During the above operation, when hoisting and lowering the U-shaped counterweight structure, the required length of rigging is selected according to the situation to ensure that the wire rope of the crane does not interfere with the ship's side.

[0042] It can be understood that the U-shaped counterweight structure of the present invention can be used for horizontal laying of dynamic flexible risers, or vertical or horizontal laying of other hoses, umbilical cables and submarine cables, and the above-mentioned operation method can be referred to.

[0043] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A U-shaped counterweight structure for deepwater dynamic pipe and cable laying, characterized in that: It includes a counterweight body and a lifting lug assembly arranged on the counterweight body; The counterweight body is provided with a through groove penetrating the first surface and the second surface opposite thereto, and the through groove also penetrates the adjacent third surface of the counterweight body to form a U-shaped groove for the dynamic flexible pipe cable to fit therein; The U-shaped groove comprises a first U-shaped segment that penetrates the first surface, and a second U-shaped segment that is axially connected to the first U-shaped segment and penetrates the second surface; the first U-shaped segment is trumpet-shaped, and the first U-shaped segment is connected to the second U-shaped segment at one end with a smaller diameter, and is connected to and penetrates the first surface at one end with a larger diameter; The eye assembly includes at least one first suspension eye, which is arranged on the first surface of the counterweight body and is used to connect with the suspension rigging to suspend the U-shaped counterweight structure on the dynamic flexible tube cable.

2. The U-shaped counterweight structure according to claim 1, characterized in that: The inner surface of the U-shaped groove is a smooth surface, and the junction between the U-shaped groove and the surface of the counterweight body is chamfered to form a transitionally smooth connection.

3. The U-shaped counterweight structure according to claim 1, characterized in that: All edges and vertices of the counterweight body are rounded to form rounded transitions.

4. The U-shaped counterweight structure according to claim 1, characterized in that: There are four first hanging ears, which are arranged in a square shape on the first surface.

5. The U-shaped counterweight structure according to claim 1, characterized in that: The eye assembly further includes at least one second suspension eye disposed on a second surface of the counterweight body.

6. The U-shaped counterweight structure according to claim 5, characterized in that: There are four second hanging ears, which are arranged in a square shape on the second surface.

7. The U-shaped counterweight structure according to claim 1, characterized in that: The lifting eye assembly further includes at least one lifting eye disposed on a fourth surface of the counterweight body opposite to the third surface.

8. The U-shaped counterweight structure according to claim 7, characterized in that: One lifting lug is provided, and when the U-shaped counterweight structure is lifted and lowered by the lifting lug, the lifting lug is located just above the center of gravity of the U-shaped counterweight structure.

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