KR101873453B1 - Half lurking equation marine construction - Google Patents

Abstract

A semi-submergible offshore structure is disclosed. A semi-submergible offshore structure according to an embodiment of the present invention includes a platform; A pontoon disposed below the platform and providing buoyancy to the platform; A column interposed between the platform and the pontoon, the column supporting the platform with respect to the pontoon; And a column load reduction unit disposed in the lateral direction of the column with respect to the column, the column load reduction unit extending in the vertical direction and reducing the environmental load due to the fluid flowing into the column.

Description

Half lurking equation marine construction {

The present invention relates to semi-submergible offshore structures.

In general, semi-submergible offshore structures are used as drilling rigs to drill crude oil and gas buried in the seabed. For example, a semi-submergible offshore structure may include a platform on which a drilling rig is installed, a pontoon forming buoyancy below the platform, and a plurality of columns connecting the platform and the pontoon.

Such semi-submergible offshore structures need to maintain a constant position for stable drilling operations. For this purpose, the semi-submergible offshore structure may have a dynamic positioning system, such as an azimuth thruster, or may be installed via a mooring system.

On the other hand, the wind and ocean currents in the working area make it difficult to maintain the position of semi-submergible offshore structure (position keeping). In other words, the wind can act on the semi-submergible offshore structure to generate six degrees of freedom motion. Sea currents can act as an external force against the subsurface part of the semi-submergible offshore structure, resulting in motion on semi-submerged offshore structures.

In particular, winds and currents flowing toward the column increase the environmental load on the column, making it difficult to maintain the position of the semi-submergible offshore structure. In order to solve this problem, it is necessary to develop a semi-submergible offshore structure that can maintain an accurate position even under the action of environmental loads caused by winds and currents in the present working area.

An embodiment of the present invention is to provide a semi-submergible offshore structure capable of stably maintaining its position under the action of environmental loads due to wind and current.

According to an aspect of the present invention, there is provided an apparatus comprising: a platform; A pontoon disposed below the platform and providing buoyancy to the platform; A column interposed between the platform and the pontoon, the column supporting the platform with respect to the pontoon; And a column load reducing section extending in the vertical direction with respect to the column, the column load reducing section being disposed laterally of the column and reducing an environmental load caused by the fluid flowing into the column. have.

The column load reducing portion may be formed to be movable toward the fluid flowing into the column.

The column load reduction unit may further include a driving unit that provides a driving force to move the column load reduction unit.

The column load reducing portion may be provided in a plate shape.

The column load reducing portion may have a width different from that of the upper portion and the lower portion with respect to the water surface.

When the environmental load due to the sea current is greater than the environmental load due to wind, the width of the lower portion of the column can be made larger than the width of the upper portion.

When the environmental load due to wind is larger than the environmental load due to the current flow, the width of the column load reducing portion may be formed to be larger than the width of the lower portion.

According to the embodiment of the present invention, since the fluid introduced into the column is disturbed by the column load reducing section spaced apart from the column, the environmental load acting on the column by the fluid flowing into the column is effectively reduced, The position can be stably maintained.

1 is a front view of a semi-submergible offshore structure according to an embodiment of the present invention.
FIG. 2 is a view showing a semi-submergible offshore structure according to an embodiment of the present invention viewed from the left side.
3 is a view showing a semi-submergible offshore structure according to an embodiment of the present invention viewed from above.
Fig. 4 is a view showing a modification of the column load reducing section of Fig. 2;
5 and 6 are views for explaining the operation of the column load reducing unit of a semi-submergible offshore structure according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. It is to be understood, however, that the invention is not to be limited to the specific embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described in detail with reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Referring to the accompanying drawings, the same or corresponding components are denoted by the same reference numerals, do. In the following description, terms such as first and second terms are used to describe various components, and the meaning is not limited to itself, and is used only for the purpose of distinguishing one component from another component do.

FIG. 1 is a front view of a semi-submergible offshore structure according to an embodiment of the present invention. FIG. 2 is a side view of a semi-submergible offshore structure according to an embodiment of the present invention. FIG. 3 is a top view of a semi-submergible offshore structure according to an embodiment of the present invention.

1 to 3, a semi-submergible offshore structure 100 according to an embodiment of the present invention includes a platform 110, a pontoon 120, a column 130, and a column load reduction unit 140 do.

The platform 110 is located above the water surface. The platform 110 may be equipped with various equipment (not shown) such as drilling equipment.

A pontoon 120 is disposed below the platform 110. The pontoon 120 provides buoyancy to the platform 110. The pontoons 120 are capable of buoyancy control. In this case, the pontoons 120 may be provided with a ballast tank (not shown).

A column 130 is interposed between the pontoons 120 and the platform 110. Column 130 interconnects platform 110 and pontoon 120 and supports platform 110 relative to pontoon 120.

The column 130 may extend vertically from the pontoon 120 toward the platform 110 as shown in FIG. Or the column may extend obliquely from the pontoon toward the platform, though not shown.

The column 130 may have a rectangular cross section as shown in FIG. In addition, although the column is not shown, it may have a circular or cross-section of various shapes.

The column 130 may be provided in plurality.

The column load reducer 140 is spaced laterally of the column 130 with respect to the column 130. In this case, the column load reducing unit 140 may be disposed apart from the column 130 in the outward direction of the platform 110 as shown in FIGS.

The column load reducing section 140 is formed to extend in the vertical direction. In this case, the column load reducing section 140 may extend along the extending direction of the column 130.

For example, the column load reduction unit 140 may extend vertically along the extending direction of the column 130 extending vertically as shown in FIG. Or the column load reducing portion may be inclinedly extended along the extending direction of the column that is not shown, but which extends in an inclined manner.

In this embodiment, the column load reduction unit 140 extending in the vertical direction can be supported on the upper surface of the platform 110 and the lower surface of the pontoons 120 as shown in FIG. This will be described later.

In another embodiment, the column load reducing portion extending in the vertical direction is not shown, but it goes without saying that the column supporting portion may be arranged in various supporting structures such that the upper portion is supported on the lower surface of the platform and the lower portion is supported on the upper surface of the pontoon.

Such a column load reducing unit 140 disturbs the flow of the fluid flowing into the column 130, thereby reducing the environmental load due to the fluid flowing into the column 130. Here, the fluid entering the column 130 may be wind or current, and the environmental load refers to the load acting on the column 130 by wind or current.

More specifically, when fluid flows into the column, the pressure on the side of the column on which the fluid flows is greater than the pressure on the opposite side. This pressure differential acts as an environmental load on the column and makes it difficult to maintain the position of semi-submergible offshore structures.

At this time, when the column load reduction unit 140 is spaced apart from the column 130, the fluid moving toward the column 130 may be disturbed by the column load reduction unit 140 and may be introduced into the column 130 have. In this case, the difference between the pressure on the side of the column 130 on which the fluid flows (that is, between the column load reduction section 140 and the column 130) and the pressure on the opposite side of the column load reduction section 140 Can be reduced.

Therefore, the environmental load acting on the column 130 by the fluid flowing into the column 130 can be effectively reduced, and the semi-submergible offshore structure 100 according to the present embodiment can be stably maintained in the working area .

The column load reducing section 140 may be formed to be movable toward the fluid flowing into the column 130. In this case, the column load reducing unit 140 can effectively reduce the environmental load acting on the column 130 corresponding to the fluid flowing in various directions.

The semi-submergible offshore structure 100 according to the present embodiment may further include a driving unit 150 that provides a driving force to move the column load reducing unit 140. At this time, the column load reducing unit 140 can be turned around the column 130 by the driving force of the driving unit 150 as shown in FIG.

The driving unit 150 may include, but is not limited to, a motor 151.

When the driving unit 150 is the motor 151, the motor 151 may be provided to transmit the rotational force to the upper and lower portions of the column load reducing unit 140 as shown in FIG.

A motor 151 for providing a rotational force to the upper portion of the column load reducing portion 140 is installed inside the platform 110 and a motor 151 for providing rotational force to the lower portion of the column load reducing portion 140 And may be installed inside the pontoon 120.

At this time, the motor 151 installed on the platform 110 and the motor 151 installed on the pontoon 120 can be synchronized to operate together. In this case, the column load reduction unit 140 can perform the turning operation effectively by receiving the rotational force simultaneously from the upper and lower portions.

In the present embodiment, the column load reducing section 140 can receive the driving force through the upper rotation supporting section 160 and the lower rotation supporting section 170. [

The upper rotation support portion 160 may include an upper rotation shaft 161 and an upper support member 162 as shown in FIG.

The upper rotating shaft 161 protrudes from the upper surface of the platform 110 and can be connected to the motor shaft 151a of the motor 151 installed on the platform 110. [ The upper rotating shaft 161 can rotate integrally with the motor shaft 151a when the motor 151 installed on the platform 110 rotates.

The upper support member 162 may be fixedly coupled to the upper end of the upper rotation shaft 161 at one end. In this case, the upper support member 162 can be rotated along the rotating upper rotating shaft 161.

The other end of the upper support member 162 may extend laterally of the column 130 to support the upper end of the column load reducing portion 140 spaced apart from the column 130. In this case, the upper end of the column load reducing section 140 can be rotated along the upper support member 162.

The lower rotation support portion 170 may include a lower rotation shaft 171 and a lower support member 172 as shown in FIG.

The lower rotating shaft 171 may protrude from the lower surface of the pontoon 120 and may be connected to the motor shaft 151a of the motor 151 installed in the pontoon 120. [ The lower rotating shaft 171 can rotate integrally with the motor shaft 151a when the motor 151 installed on the pontoon 120 rotates.

One end of the lower support member 172 may be fixedly coupled to the lower end of the lower rotation shaft 171. In this case, the lower support member 172 can be rotated along the rotating lower rotating shaft 171.

The lower support member 172 can support the lower end portion of the column load reduction portion 140 spaced apart from the column 130 by extending the other end in the lateral direction of the column 130. In this case, the lower end of the column load reducing section 140 can be rotated along the lower support member 172.

It is needless to say that the semi-submergible offshore structure 100 according to the present embodiment may be provided in various structures capable of providing the driving force of the driving unit 150 to the column load reducing unit 140.

In the present embodiment, the column load reducing section 140 may be provided in a plate shape, but the column load reducing section 140 may be provided in various shapes capable of disturbing the fluid flowing into the column 130 Of course.

The column load reduction unit 140 may be formed extending from the water surface to the water surface as shown in FIG. At this time, the column load reducing section 140 can reduce the load caused by the wind on the upper part of the water surface, and reduce the load caused by the current on the lower part.

In the working area where the semi-submergible offshore structure 100 according to the present embodiment is installed, the environmental load due to the action of either the wind or the sea current may be larger than the environmental load due to another action. At this time, the column load reduction unit 140 may be formed to have different widths of the upper and lower portions with respect to the water surface.

For example, when the environmental load due to the current is greater than the environmental load due to wind, the column load reduction unit 140 may be formed such that the lower width is larger than the upper width as shown in FIG. In this case, the column load reducing section 140 can effectively reduce the environmental load due to the current flow.

As another example, when the environment load due to wind is larger than the environmental load due to the current, the column load reduction unit 140 'may be formed such that the upper width is larger than the lower width as shown in FIG. 4 is a view showing a modification of the column load reducing section of Fig. 2. Fig.

In this case, the column load reducing section 140 'can effectively reduce the environmental load due to the wind.

In addition, it is needless to say that the column load reducing portion may be formed in various ways such that the widths of the upper and lower portions are the same.

Referring to FIGS. 1 and 3, the column load reduction unit 140 may be provided corresponding to the number of the columns 130. In this case, the plurality of column load reduction sections 140 may be provided with the driving section 150 and may be supported by the upper rotation support section 160 and the lower rotation support section 170 so as to be rotatable.

5 and 6 are views for explaining the operation of the column load reducing unit of a semi-submergible offshore structure according to an embodiment of the present invention. 5 and 6 illustrate a semi-submergible offshore structure 100 according to an embodiment of the present invention, viewed from above.

3, 5 and 6, the operation of the column load reducing section 140 of the semi-submergible offshore structure 100 according to the embodiment of the present invention will be described. In the semi-submergible offshore structure 100 according to the present embodiment, four columns 131, 132, 133, and 134 and four column load reduction sections 141, 142, 143, 132, 133, and 134, and each of the column load reduction sections 141, 142, 143, and 144 is provided with a width of the lower portion larger than that of the upper portion, .

3, 5, and 6, the + X axis direction is defined as the forward direction of the semi-submergible offshore structure 100 and the + Y axis direction of the semi-submergible offshore structure 100 The column 131 located on the left rear side is referred to as a first column 131 and the column load reduction section 141 provided corresponding to the first column 131 is referred to as a first column load reduction section 143 and 144 located in the clockwise direction with respect to the first column 131 and the first column load reduction section 141 and the respective column load reduction sections 142, Quot ;, " second ", " third ", and " fourth "

Referring first to FIG. 3, a semi-submergible offshore structure 100 according to an embodiment of the present invention may be disposed in a working area.

At this time, the column load reducing sections 141, 142, 143, and 144 may be disposed in an initial installation state. In this case, the first column load reducing section 141 and the fourth column load reducing section 144 are spaced apart from each other in the left direction with respect to the first column 131 and the fourth column 134 as viewed in FIG. 3 . 3, the second column load reducing section 142 and the third column load reducing section 143 are disposed apart from each other in the right direction with respect to the second column 132 and the third column 133 .

The column load reduction sections 141, 142, 143, and 144 arranged in this manner can move toward the current flowing into each of the columns 131, 132, 133, and 134.

Referring to FIG. 5, in the working area, the sea current can flow from the left rear to the right front side with respect to the semi-submergible offshore structure 100 according to the present embodiment as viewed in FIG. In this case, the current may flow into the first column 131, the second column 132, and the fourth column 134.

At this time, the first column load reducing section 141, the second column load reducing section 142, and the fourth column load reducing section 144 are disposed in the first column 131, the second column 132, (134). ≪ / RTI >

At this time, the third column load reducing section 143 may be disposed in an initial installation state. In this case, the third column load reducing section 143 is configured to prevent the third column load reducing section 143 from colliding with the platform 110 or the pontoons (120 in FIG. 1) in the course of turning operation toward the current flowing from the left- It may be preferable not to perform the turning operation.

The flow of currents can change over time.

Referring to FIG. 6, in the working area, the ocean current can flow from the rear to the front for the semi-submergible offshore structure 100 according to the present embodiment when viewed in FIG. In this case, the current may flow toward the first column 131 and the second column 132.

At this time, the first column load reduction unit 141 and the second column load reduction unit 142 can be turned toward the current flowing toward the first column 131 and the second column 132, respectively.

At this time, the third column load reducing section 143 and the fourth column load reducing section 144 can be disposed in an initial installation state. In this case, the third column load reducing section 143 and the fourth column load reducing section 144 are disposed in the platform 110 or the pontoons (see FIG. 1) in the process of turning toward the current flowing in from the rear, It may be desirable not to pivot so as to prevent collision with the first and second wheels 120, 120.

Although not shown, the column load reduction unit corresponding to each column may be operated in various manners to disturb the current flowing in various directions.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, many modifications and changes may be made by those skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims. The present invention can be variously modified and changed by those skilled in the art, and it is also within the scope of the present invention.

100: semi-submergible offshore structure
110: Platform
120: pontoon
130: Column
140, 140 ': column load reducing section
150:
151: Motor
160: Upper rotation support
161: upper rotating shaft
162: upper support member
170: Lower rotation support
171: Lower rotating shaft
172: Lower support member

Claims (7)

A platform;
A pontoon disposed below the platform and providing buoyancy to the platform;
A column interposed between the platform and the pontoon, the column supporting the platform with respect to the pontoon;
An upper portion extending upwardly and downwardly with respect to the column so as to be supported by the platform and a lower portion supported by the pontoons and being spaced apart from the platform in the outward direction of the platform and reducing the environmental load by the fluid flowing into the column A column load reducing section; And
Wherein the column load reduction portion includes a driving portion that provides a driving force so as to move so as to be directed toward a fluid flowing into the column. delete delete The method according to claim 1,
Wherein the column load reduction portion is provided in a plate shape. The method according to claim 1,
Wherein the column load reducing part is formed such that widths of the upper part and the lower part are different with respect to the water surface. 6. The method of claim 5,
Wherein when the environmental load due to the current is greater than the environmental load due to the wind, the column load reduction portion is formed such that the width of the lower portion is greater than the width of the upper portion. 6. The method of claim 5,
Wherein when the environmental load due to the wind is greater than the environmental load due to the current, the column load reduction portion is formed such that the width of the upper portion is larger than the width of the lower portion.

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