KR101616848B1 - Swivel stack - Google Patents

Abstract

A swivel stack that can be provided in a turret of a floating structure is disclosed. A swivel stack according to an embodiment of the present invention includes a plurality of swivelers stacked in a vertical direction, a connecting member extending in a vertical direction and connected to an outer portion of at least two swivels of the plurality of swivels, And the other end may include a torque arm connected to the connecting member. When the floating structure rotates about the turret, the outer side of the swivel connected by the connecting member can rotate together with the floating structure.

Description

Swivel Stack {SWIVEL STACK}

The present invention relates to a swivel stack.

Generally, the FPSO (floating oil production cargo storage and retrieval facility) that collects gas or crude oil from the seabed is equipped with a turret to aid in harvesting.

The turret is usually mounted in a vertical opening or moon pool at one end of the ship, usually at the forefront, and secured to the seabed by a chain or the like, thereby mooring the ship to the seabed.

Further, the turret is installed so that the ship can rotate around the turret. In other words, the turret is fixed to the platform of the submarine channel, and a sliding bearing is interposed between the turret and the vertical opening (the portal) of the ship, so that the ship can rotate naturally around the turret by the action of wind, have. This allows the gas or crude oil to be stably transported to the ship side through a pipe or the like in the fixed turret, even if wind, tide or wave acts during the drilling operation.

Meanwhile, the turret may be provided with a swivel stack including a plurality of swivels. Each swivel is placed vertically, like a tower, and the gas or oil taken from the bottom of the seabed or the well can be transferred to each part of the vessel through this swivel stack. The inner side of each swivel remains stationary with the turret, and the outer side is connected to the hull so that it can rotate together as the ship rotates about the turret. Here, a pipe for transferring gas or crude oil to the ship is connected to the outer side.

In general, a torque arm is connected to the outer side of the swivel, so that the load can be transmitted to the pipe connecting portion when the outer side of the swivel rotates together with the ship. As a result, the risk of damage to the piping connection portion is lowered, so that the outer side of the swivel can be stably rotated.

However, the above-described conventional techniques have the following problems.

Since the swivel stack has a plurality of torque arms connected to the hull, the overall structure of the swivel stack is complicated and the productivity is low.

Further, since the torque arm is an expensive product, there is a problem that the manufacturing cost of the swivel stack increases when a plurality of the torque arms are provided.

U.S. Published Patent Application No. 6093068

An embodiment of the present invention is to provide a swivel stack of a simplified structure.

Embodiments of the present invention are also intended to provide a swivel stack that can save material costs.

Further, an embodiment of the present invention is to provide a swivel stack which can facilitate maintenance of the swivel.

According to an aspect of the present invention, a swivel stack provided in a turret of a floating structure includes a plurality of swivel laminates stacked in a vertical direction, a plurality of swivels extending in a vertical direction and connected to outer sides of at least two swivels Member and one side thereof may be connected to the floating structure and the other side may comprise a torque arm connected to the connecting member, and when the floating structure rotates about the turret, The outer side can rotate with the floating structure.

The connecting member and the swivel may be slidable in a direction perpendicular to each other.

To this end, a depression is formed in the outer side of the swivel, and the connection member includes a protrusion inserted into the depression, and the depression may be provided with a bearing for supporting the sliding movement of the connection member and the swivel .

The connection member may be provided with a depression, and the outer side of the swivel may include a protrusion inserted into the depression, and the depression may include a bearing for supporting the sliding movement of the connection member and the swivel.

The bearing portion may include three bearing members disposed on the left, right, and tip ends of the projecting portion, respectively.

According to an embodiment of the present invention, a swivel stack of a simplified structure can be provided.

It also provides a swivel stack that can save material costs.

Further, it is possible to provide a swivel stack which can facilitate the maintenance of the swivel.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 schematically shows the construction of a general swivel stack; FIG.
Fig. 2 is an enlarged perspective view of a portion A of Fig. 1; Fig.
3 is a perspective view of a swivel stack according to an embodiment of the present invention.
4 is a plan view of a swivel stack according to another embodiment of the present invention;
5 is a plan view of a swivel stack according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the following description of the present invention, detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

Hereinafter, a swivel stack according to embodiments of the present invention will be described as being provided on a turret installed on a ship, but the present invention is not limited thereto. The swivel stack according to embodiments of the present invention can be equally applied to various floating structures such as a marine plant as well as a ship.

Before describing the present invention in more detail, the operation of the ship centered on the turret and the turret will be described.

Turrets may be equipped with floating structures that drill gas or crude oil from the seabed, such as drill rigs or FPSO (Floating Production Storage and Offloading). It may be divided into an internal turret or an external turret depending on where the hull is located.

The turret allows the ship to freely rotate about the turret when the ship flows by the action of wind, tide or wave while the gas or crude oil is being transported. The gas or crude oil, It can be stably transported to the ship side through the piping of the ship. For example, there is no possibility that various pipes such as a riser are caught by the flow of the ship.

In the case of an inner turret, a vertical opening (a portal) through the hull can be formed inside the vessel, and the turret can be installed in such a vertical opening. The vertical opening may be provided with a plurality of bearings such that the hull is rotatable about the turret. That is, the one side and the other side of each bearing can contact the hull and the turret, respectively, to perform rolling motion, thereby helping to smoothly implement the relative rotational movement of the hull and the turret.

The turret may include, from the bottom up, the bottom turret, the top turret, the piping deck, the manifold deck, the top and bottom gantries, and the like in the above order. A swivel stack and a utility pipe connected to the swivel stack may be installed inside the upper gantry. Utility pipes can be supported by piping decks and manifold decks, one side can be connected to each part of the vessel and the drilled crude oil or gas can be transferred to each part of the vessel. The other side of the utility pipe can be connected to a riser installed in the turret. The riser is connected to a submarine block platform so that the gas or crude oil from the block can be transferred to the utility pipe through the riser.

1 is a view schematically showing the construction of a general swivel stack.

As shown, the swivel stack has a plurality of swivels arranged in the vertical direction. The bottom-most swivel may be a production swivel 10. It can receive crude oil or gas from a riser installed in the turret and transfer it to the hull via a utility pipe. Above the production swivel 10 various swivels may be placed, such as a water injection swivel 20, a gas export swivel 30, a gas lift and injection swivel 40, have. 1, there may be a utility swivel, a test swivel, an electrical / optical swivel, and a power / signal swivel. As such, each swivel included in the swivel stack performs its function and can safely transport crude oil or gas drilled from the seabed to the hull.

1, the first torque arm 11 is attached to the production swivel 10, the second torque arm 21 is attached to the water injection swivel 20, and the second torque arm 21 is fixed to the gas lift and injection swivel 40 And the third torque arm 41 may be respectively connected. These torque arms 11, 21 and 41 are connected to the swivels 10, 20 and 40 and a hull (mainly a swivel supporting structure or a gantry structure connected to the hull). As will be described later, since the outer side of the swivel is connected to the hull by the torque arm, the hull can rotate together with the hull when the hull rotates around the turret. Further, as described above, since the torque arm is usually provided for each swivel, the overall structure is complicated and the material cost can be raised. The present invention can solve such a problem, and the details will be described later.

FIG. 2 is a perspective view enlargedly showing a portion A of FIG. 1, and a portion of the swivel 40 is shown in a cutaway view to show both the outside and the inside of the swivel 40. FIG.

An inner core 41 may be located at the center. The inner core 41 does not rotate together with the vessel when the vessel is rotated, as in the case of various pipes installed in the turret and the turret. The inner core 41 may be provided with a first flow path 42 for transferring drilled gas or crude oil. An inner ring 43 may be disposed on the outer circumferential surface of the inner core 41. The inner ring 43 is also an element that does not rotate when the ship rotates. Hereinafter, the fixing elements such as the inner core 41 and the inner ring 43 will be referred to as inner portions of the swivel.

An outer ring (44) may be disposed on the outer circumferential surface of the inner ring (43). Since the outer ring 44 is connected to the hull through the torque arm, the outer ring 44 rotates together with the ship when the ship rotates. The relative rotation of the inner ring 43 and the outer ring 44 can be realized by the bearing 46. Hereinafter, the element rotating together with the ship is referred to as the outer side of the swivel.

The inner ring 43 and the outer ring 44 may be recessed by a predetermined distance in the direction away from each other so that a second flow path 45 is formed between the inner ring 43 and the outer ring 44 . The crude oil or gas supplied to the swivel 40 through the first flow path 42 flows into the second flow path 45 and flows through a utility pipe communicating with the pipe connection part 47 of the outer ring 44, Can be transferred to each part.

3 is a perspective view of a swivel stack 100 according to an embodiment of the present invention. For convenience of explanation, a part of the structure of the swivel stack 100 in which similar shapes are repeated is omitted. Therefore, another swivel may be further disposed below the first swivel 110 disposed at the bottom, and another swivel may be further disposed above the fourth swivel 140 disposed at the uppermost position. The first to fourth swivels 110, 120, 130, and 140 described below are merely examples for illustrating the present invention.

The swivel stack 100 according to the present embodiment may include a plurality of swivels. As described above, the four swivels 110, 120, 130 and 140 are exemplified. In the first swivel 110 and the third swivel 130, a utility pipe connected to each part of the ship Pipe connection portions 115 and 135 that can be connected to each other may be respectively formed. Also, the first to fourth swivels 110, 120, 130, and 140 may have piping connections to communicate with utility pipes.

The swivel stack 100 according to the present exemplary embodiment may include a connecting member 150. The connecting member 150 may include at least two swivels of the plurality of swivels 110, In all four swivels). Accordingly, the plurality of swivels 110, 120, 130, and 140 can be mutually connected, and particularly, each of the outer sides thereof can be moved (rotated) integrally through the connecting member 150.

In this embodiment, instead of connecting the torque arm to each swivel, the torque arm 160 may be connected to the connecting member 150 as described above. 3, one side of one torque arm 160 is connected to the side of the hull 1, and the other side of the torque arm 160 is connected to each of the swivels 110, 120, 130, 140 (Not shown).

The outer side of each of the plurality of swivels 110, 120, 130 and 140 is rotatable together with the hull 1 when the hull 1 rotates around the turret. In the conventional case, a separate torque arm has to be connected to each swivel so that the structure becomes complicated and the material cost rises unreasonably. However, according to the swivel stack 100 according to the present embodiment, only one or at least a torque arm is installed The structure is much simpler and economical advantage is also great.

3, each of the swivels 110, 120, 130, and 140 has a cylindrical structure having the same diameter. However, in the case of a plurality of swivels included in the swivel stack, the diameter of the swivel decreases gradually toward the upper portion have. In this case, the connecting member 150 is not a straight member as shown in FIG. 3 but may be a member adapted to a difference in diameter of the swivel, for example, have. Alternatively, the connecting member 150 may be provided in a straight shape and arranged to directly contact the swivel having the largest diameter, and may be connected to the swivel having a small diameter through a separate auxiliary connecting member (not shown) disposed horizontally.

On the other hand, the connecting member and each swivel can be slidable in the vertical direction with respect to each other. This makes it possible to stably install the swivel, to reliably remove the swivel even when maintenance is required, and to re-install the swivel after the maintenance is completed, without requiring a separate alignment confirmation operation. To illustrate this, FIG. 4 is presented.

4 is a top view of a swivel stack 200 according to another embodiment of the present invention.

As shown, the swivel 240 and the connecting member 250 may be slidable relative to each other. Specifically, a depression 245 may be formed on the outer side of the swivel 240, more precisely the swivel 240, to be recessed inward of the swivel 240. The connection member 250 may be formed with a protrusion 255 protruding toward the swivel 240. The protruding portion 255 of the connecting member 250 can be inserted into the depressed portion 245 of the swivel 240 and the space between the protruding portion 255 and the surface of the depressed portion 245 can be supported by the bearing portion have.

The bearing portion is disposed in the depression 245 to smoothly support the sliding movement of the connecting member 250 and the swivel 240. In this embodiment, the bearing portion is provided on the surface of the depressed portion 245 of the swivel 240 The bearing members 270, 271 and 272 can support the protrusions 255 of the connecting member 250 at three points. 4, two bearing members 270 and 271 may be disposed on the left and right sides of the protrusion 255, respectively, when viewed from the insertion direction of the protrusion 255, And the other one of the bearing members 272 may be disposed on the distal end side of the protruding portion 255.

In FIG. 4, the bearing members 270, 271, and 272 are formed as roller bearings. However, the bearing members 270, 271, and 272 are merely examples, and the bearings may be formed through a ball bearing or the like.

5 is a plan view of a swivel stack 300 according to another embodiment of the present invention. The present embodiment is based on the similarity to FIG. 4, and also shows a structure in which the swivel 340 and the connecting member 350 are mutually slidable.

4, the concave portion 355 may be formed on the connecting member 350, and the protrusion 345 may be formed on the outer side of the swivel 340. In this case, The protrusion 345 formed on the outer side of the swivel 340 is inserted into the depression 355 of the connecting member 350 and is supported by the bearing portion and is capable of sliding motion.

Like the embodiment of FIG. 4, this embodiment also illustrates a bearing portion including three roller bearings 370, 371, and 372, and the present invention is not limited thereto as described above.

It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. It will be understood that various changes, modifications, or substitutions may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

1: Hull 100: Swivel stack
110, 120, 130, 140: swivel 115, 135: pipe connection
150: connecting member 160: torque arm

Claims (5)

In a swivel stack provided in a turret of a floating structure,
A plurality of swivels stacked in a vertical direction;
A connecting member extending in the vertical direction and connected to an outer side of at least two of the plurality of swivels; And
One side connected to the floating structure and the other side including a torque arm connected to the connecting member,
As the floating structure rotates about the turret, the outer side of the swivel connected by the connecting member rotates together with the floating structure,
Wherein the connecting member and the swivel are slidable in a direction perpendicular to each other. delete The method according to claim 1,
Wherein a depression is formed on an outer side of the swivel, the connection member includes a protrusion inserted into the depression, and the depression includes a bearing portion for supporting the sliding movement of the connection member and the swivel. The method according to claim 1,
Wherein the connecting member is formed with a depression, the outer side of the swivel includes a protrusion inserted into the depression, and the depression is provided with a bearing portion for supporting the sliding movement of the connecting member and the swivel. The method according to claim 3 or 4,
Wherein the bearing portion includes three bearing members disposed on left, right, and tip ends of the protrusion, respectively.

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