KR20140086200A - Assembling and deassembling heave motion reduction apparatus for semi-submersible structure - Google Patents

Abstract

Disclosed is a detachable vertical motion reduction apparatus for semi-submersible structures. The present invention relates to a detachable vertical motion reduction device for a semi-submergible structure, comprising: a truss unit detachably connected to a semi-submergible structure; A heave plate coupled to the other side of the truss unit to reduce vertical motion of the semi-submerged structure; And a lifting guide member connected to at least one of the truss unit and the hive plate and guiding the lifting of the semi-submergible structure when the truss unit is coupled to the semi-submergible structure.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a semi-submersible structure,

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a detachable vertical motion reduction apparatus for a semi-submergible structure, and more particularly, to a detachable vertical movement reducing apparatus for a semi-submergible structure that is detachably coupled to a semi-submergible structure, And a motion reduction device.

Semi-submersible offshore structures such as Drilling RIGs are equipped with an expensive drilling system for drilling on the upper deck, and are suspended and used at a fixed position in the sea.

The drilling rig is greatly influenced by the vertical movement of the drilling rig because various equipments are extended from the upper deck of the drilling rig to the seabed during drilling.

Floating Production Unit (FPU), which is a kind of semi-submergible offshore structure, is also affected by up and down movement of the hull because the crude oil production facility is floated in the sea.

In other words, the semi-submergible floating structure is used floating in the sea, so that the movement is inevitably caused by the flow of seawater. Heave motion or vertical acceleration, which is a vertical motion, greatly affects the performance of various drilling equipments and crude oil production equipments, and there is a risk that these equipments and equipments are damaged.

Especially, the operation rate of semi-submergible offshore structure is greatly affected by the sea condition, and the heave motion directly affects the work rate. Therefore, a vertical motion reduction device is installed below the semi-submergible offshore structure to suppress the vertical motion.

A conventional heave motion reduction apparatus, for example, as described in U. S. Patent Publication No. < RTI ID = 0.0 > 2012-0034034, < / RTI > is adapted to connect a support structure of a vertical motion reduction apparatus to a column of a semi-submergible offshore structure, The rear support structure is installed in the direction of the sea floor.

Since the conventional vertical motion reduction device is lowered from the sea surface below the sea surface, the vertical motion reduction device can be shaken due to the influence of waves or wind on the sea surface during the descent. As a result, the vertical motion reduction device and the semi-submergible offshore structure There is a danger that various equipment and facilities may be damaged.

In addition, when the vertical motion reduction device is moved to the target area, a separate fixing means for fixing the vertical motion reduction device to the semi-submergible offshore structure is required, and a large-sized vertical motion reduction device is disposed in the space between the column and the pontoon There are also difficulties in doing.

Furthermore, it is necessary to maintain and repair the vertical motion abatement apparatus that has been installed, so that the supporting structure of the vertical motion abatement apparatus or a separate pulling means for separating the heave plate must be used. There is a downside.

U.S. Patent Publication No. 2012-0034034 (TECHNIP FRANCE) 2012. 02. 09.

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a detachable vertical motion reduction device for a semi-submergible structure that can be conveniently installed at sea, can perform maintenance and repair operations safely and conveniently, .

According to an aspect of the present invention, there is provided a semi-submergible structure, comprising: a truss unit detachably coupled to a semi-submerged structure; A heave plate coupled to the other side of the truss unit to reduce vertical motion of the semi-submergible structure; And a lifting guide member connected to at least one of the truss unit and the hive plate to guide lifting of the semi-submergible structure when the truss unit is coupled to the semi-submergible structure, A detachable vertical motion reduction device of the present invention can be provided.

The truss unit may include a plurality of truss legs each having a first flange at one side and coupled to a second flange provided at a lower side of the semi-submergible structure in a bolted manner.

Two pairs of the truss legs may be provided and each pair may be arranged to be mutually symmetrical in the longitudinal direction of the semi-submergible structure with respect to the center of the semi-submergible structure.

The truss unit may further include a plurality of truss reinforcement members for interconnecting the plurality of truss legs to reinforce the plurality of truss legs.

The lifting guide member connected to the truss unit is disposed inside the plurality of truss legs and the truss unit is provided inside the plurality of truss legs to prevent interference between the lifting guide member and the inner wall of the plurality of legs And an interference preventing member for preventing interference.

The hive plate may include a base plate having a plurality of holes coupled to the other side of the truss unit and serving as a drain passage for seawater.

A moonpool may be provided on the base plate.

The plurality of holes include a plurality of small holes provided on the base plate on both sides in the longitudinal direction of the door frame; And a plurality of large holes provided in a region of the base plate excluding both sides in the longitudinal direction thereof and having a larger diameter than the plurality of small holes.

The heave plate may further include a plurality of extension plates provided in the longitudinal direction of the base plate.

The lifting guide member may comprise a chain.

The lifting guide member may be connected to the semi-submergible structure to support the truss unit when the truss unit is separated from the semi-submerged structure.

A guider provided on the semi-submergible structure for guiding the lifting and guiding of the lifting guide member; And a stopper provided on the semi-submergible structure for stopping the lifting guide member.

Said semi-submerged structure comprising: a deck; A plurality of columns coupled to an upper portion of the deck to support the deck; And a plurality of pontoons coupled to a lower portion of the plurality of columns to support the plurality of columns and to which the truss unit is detachably coupled.

According to another aspect of the present invention, there is provided a vertical motion reduction apparatus for a semi-submergible structure including a heave plate for reducing vertical motion of a semi-submergible structure and a truss unit for connecting the heave plate to the semi-submergible structure Wherein the truss unit is lifted by a lifting guide member connected to at least one of the truss unit and the hive plate and is detachably coupled to the semi-submergible structure. May be provided.

The lifting guide member connected to the truss unit may be disposed inside the truss unit.

The embodiments of the present invention can improve the convenience of installation and stability because the lifting guide member connected to the semi-submergible structure is connected to at least one of the truss unit and the hive plate, Since the vertical motion reduction device is supported by the lifting guide member even when the motion reduction device is disassembled, the maintenance and repair can be performed conveniently and stably.

1 is a front view schematically illustrating a detachable vertical motion reduction apparatus of a semi-submergible structure according to an embodiment of the present invention.
Fig. 2 is a view schematically showing a state in which the interference preventing member is provided inside the truss leg shown in Fig. 1. Fig.
3 is a plan view schematically showing the hive plate shown in Fig.
4 is a schematic view illustrating a state where a detachable vertical motion reduction device is coupled to a semi-submergible structure.
5 is an enlarged view of an area "A" of Fig. 4. Fig.
Fig. 6 is a plan view of Fig. 4 showing a state in which a heave plate is installed.
FIGS. 7 to 12 are flowcharts sequentially showing a process of installing the detachable vertical motion reduction device, which is the present embodiment, in a semi-submergible structure.

In order to fully understand the present invention, operational advantages of the present invention, and objects achieved by the practice of the present invention, reference should be made to the accompanying drawings and the accompanying drawings which illustrate preferred embodiments of the present invention.

Hereinafter, the present invention will be described in detail with reference to the preferred embodiments of the present invention with reference to the accompanying drawings. Like reference symbols in the drawings denote like elements.

In this embodiment, the semi-submerged structure includes a drilling rig line and a floating production unit (FPU).

FIG. 1 is a front view schematically showing a detachable vertical motion reduction apparatus of a semi-submergible structure according to an embodiment of the present invention. FIG. 2 is a schematic view showing a state in which the interference prevention member is provided inside the truss leg shown in FIG. Fig. 3 is a plan view schematically showing the hibb plate shown in Fig. 1, Fig. 4 is a view schematically showing a state where a detachable vertical motion reduction device is coupled to a semi-submergible structure, and Fig. 5 is an enlarged view of an area "A" in Fig. 4, and Fig. 6 is a plan view of Fig. 4 showing a state in which a hive plate is installed.

As shown in these drawings, the detachable vertical motion reduction apparatus 1 of the semi-submergible structure according to the present embodiment includes a truss unit 100 detachably coupled to a semi-submergible structure 600, A heave plate 200 coupled to the other side of the truss unit 100 to reduce vertical motion of the semi-submergible structure 600 and a truss unit 100 connected to at least one of the truss unit 100 and the hive plate 200, A lifting guide member 300 for guiding the lifting of the semi-submergible structure 600 when the unit 100 is coupled to the semi-submergible structure 600.

4, the upper part of the truss unit 100 is coupled to the lower part of the semi-submergible structure 600 to support the submergible structure 600, which reduces the vertical motion of the semi-submergible structure 600 .

4, the truss unit 100 includes a plurality of truss legs 110 having an upper portion coupled to a lower portion of the semi-submergible structure 600 in a bolt-coupling manner, A plurality of truss reinforcing members 120 for reinforcing a plurality of truss legs 110 by interconnecting the legs 110 and a plurality of truss reinforcing members 120 provided inside the plurality of truss legs 110, (See FIG. 2) for preventing interference with the inner wall of the housing 110.

1 and 5, a first flange 111 is provided at an upper end of a plurality of truss legs 110 of the truss unit 100, and a semi-submergible structure And is supported by the lifting guide member 300 at the time of attaching and detaching, so that the installation and dismounting operation can be performed simply and stably.

In the present embodiment, the plurality of truss legs 110 are provided with two pairs in order to ensure sufficient strength and rigidity during lifting, each pair of which has a semi-submergible structure Symmetrically with respect to the longitudinal direction of the substrate 600.

The plurality of truss reinforcement members 120 of the truss unit 100 are connected to the plurality of truss legs 110 to structurally reinforce the plurality of truss legs 110. [

In the present embodiment, the plurality of truss reinforcing members 120 may be provided orthogonally to the truss leg 110 as shown in FIG. 1, and may be inclined so that the center portions intersect with each other.

2, the interference preventing member 130 of the truss unit 100 is provided inside the plurality of truss legs 110 to prevent the interference of the plurality of truss legs 110 with the lifting guide member 300 And reinforces the inside of the plurality of truss legs 110 with strength.

In the present embodiment, the interference preventing members 130 may be formed in a ring shape, and as shown in FIG. 5, a plurality of the interference preventing members 130 may be provided at regular intervals.

The interference preventing member 130 may be coupled to the inner wall of the truss leg 110 in a welded manner or bolted manner.

4, the heave plate 200 is coupled to the lower portions of the plurality of truss legs 110 of the truss unit 100 and is locked down below the sea level to reduce the vertical motion of the semi-submersible structure 600 .

In this embodiment, as shown in Fig. 1, the heave plate 200 includes a base plate (not shown) having a plurality of holes 212 (see Fig. 3) coupled to a lower portion of a plurality of support legs and serving as a drain passage for seawater 210 and a plurality of extension plates 220 (see FIG. 3) provided in the longitudinal direction of the base plate 210.

3, a moonpool 211 is provided on the base plate 210 of the hive plate 200. The hinged plate 211 has a drill rig including a riser and the like, This is a large hole provided for avoiding interference and has the same function as a door frame provided on the deck 610 of the semi-submergible structure 600.

3, the base plate 210 may be formed in a rectangular planar shape, and a plurality of holes 212 may be formed in the base plate 210, and a plurality of holes 212 may be formed in the base plate 210, Drain water well.

The plurality of holes 212 are provided in a region excluding both sides in the longitudinal direction of the base plate 210 and a plurality of small holes 212a provided on both sides of the base plate 210 in the longitudinal direction of the base plate 210 And a plurality of large holes (212b) having a larger diameter than the plurality of small holes (212a).

The diameters of the plurality of holes 212 are different from each other for the structural reinforcement of the hive plate 200 in the area where the door frame 211 is provided. That is, the peripheral area of the door frame 211 can function as a drainage function of the seawater by the door frame 211, and its peripheral area can be structurally weakened by the large-hole door frame 211. Therefore, A plurality of small holes 212a having a relatively smaller diameter than the large holes 212b can be structurally reinforced in the peripheral area of the door frame 211. [

When the plurality of holes 212 are provided in the heave plate 200, the seawater circulates through the plurality of holes 212 during the vertical movement of the semi-submergible structure 600, so that the plurality of holes 212 serve as a buffer There is an advantage that the area in which the heave plate 200 contacts the seawater in the vertical direction can be reduced, and the abrupt vertical movement of the semi-submergible structure 600 can be effectively mitigated.

3, a plurality of pad eyes (PE) are provided on the base plate 210, and a lifting guide member 300 is connected to and fixed to the plurality of pad eyes PE .

3, the extension plate 220 of the hub plate 200 is provided on both longitudinal sides of the base plate 210 and structurally reinforces the base plate 210. As shown in FIG.

The base plate 210 may be provided in the shape of a rectangle and the base plate 210 may be provided with the door frame 211 so that the vertical movement of the semi-submergible structure 600 is compensated for, The center portion of the base plate 210 may be bent or fatigued.

However, if the extension plate 220 is provided on both sides of the center of the base plate 210 as shown in FIG. 3, the bending or fatigue fracture can be significantly reduced have.

Also, a plurality of large holes 212b may be formed in the extension plate 220.

As shown in FIGS. 1 and 4, the lifting guide member 300 has a lower end connected to the truss unit 100 and the hive plate 200, so that when the present embodiment is installed in the semi-submergible structure 600 The semi-submergible structure 600 is connected to a chain member C having an upper end connected thereto to guide the lifting of the present embodiment.

Therefore, since the present embodiment is supported by the semi-submergible structure 600 by the lifting guide member 300, it is possible to stably and conveniently perform the joining operation.

Further, since the present embodiment is supported by the semi-submergible structure 600 by the lifting guide member 300 when the semi-submerged structure 600 is separated to maintain and repair the present embodiment, the dismantling operation can be performed conveniently and stably .

1 and 2, the lifting guide member 300 connected to the truss unit 100 according to the present embodiment may be provided with a plurality of lifting guide members 300 for preventing corrosion by contact with seawater, And may be disposed inside the plurality of truss legs 110.

The upper portion of the lifting guide member 300 disposed inside the plurality of truss legs 110 can be fixed to the plurality of truss legs 110 (see FIG. 9) by a fixing member F including a fixing pin And the lower end of the lifting guide member 300 may be coupled to a pad eye (PE) coupled to the hub plate 200 by a combination of a bolt and a nut.

In this embodiment, the lifting guide member 300 and the chain member C include a chain.

5 and 6, the present embodiment includes a guider 400 provided on the pontoons 630 of the semi-submergible structure 600 and guiding the lifting guide member 300 up or down, 4, a stopper 500 is provided on the pontoons 630 to stop the lifting guide member 300 before coupling the embodiment to the semi-submergible structure 600 .

In the present embodiment, as shown in FIG. 5, the guider 400 may be formed in a shape having a lower side of the funnel shape and a smaller upper side than a lower side and a constant diameter.

The guider 400 may be provided over the entire height of the pontoons 630 or may be provided higher than the height of the pontoons 630 to prevent inflow of seawater.

In this embodiment, the stopper 500 can stop the lifting guide member 300 in such a manner that the lifting guide member 300 is inserted into the lifting guide member 300 through the guider 400, Or may be provided on the deck 610 of the submersible structure 600.

In this embodiment, the semi-submergible structure 600 includes a deck 610 having various drilling equipments and crude oil production facilities, a plurality of columns (not shown) coupled to the deck 610 and supporting the deck 610, And a plurality of pontoons 630 coupled to a lower portion of the plurality of columns 620 to support the plurality of columns 620 and to which the truss unit 100 is detachably coupled.

Hereinafter, the detachment method of the detachable vertical motion reduction apparatus 1 of the semi-submergible structure 600 according to the present embodiment will be described in detail with reference to FIGS. 7 to 12. FIG.

First, as shown in FIG. 7, the detachable vertical motion reduction apparatus 1 according to the present embodiment is positioned below the semi-submergible structure 600. In the present embodiment, the detachable vertical motion reduction apparatus 1 can be connected to a crane (not shown) provided in the deck 610 by a wire or the like and can be lowered to the seabed. In the undersea, a remotely operated vehicle 0.0 > ROV, < / RTI >

The present embodiment performs the coupling operation at the seabed after lowering the detachable vertical motion reduction apparatus 1 to the seabed so that the detachable vertical motion reduction apparatus 1 is prevented from being dangerous such as being shaken due to the influence of waves or winds .

8, a lifting guide member 300 of the truss unit 100 and a chain member C (one end) of which one end is connected to a winch W provided on a deck 610 of the semi-submergible structure 600, ).

9, the fixing member F, which is coupled to the first flange 111 of the truss leg 110 to fix the lifting guide member 300, is removed.

10, the first flange 111 of the truss unit 100 and the pontoon 630 of the truss unit 100 are connected to each other by using the winch W provided on the deck 610, The truss unit 100 is lifted up until the provided second flanges 631 come into contact with each other.

When the first flange 111 and the second flange 631 abut on each other, the lifting guide member 300 is stopped by the stopper 500 provided on the pontoons 630 as shown in FIG. 11 The first flange 111 and the second flange 631 are held in contact with each other.

Finally, as shown in FIG. 12, the first flange 111 and the second flange 631 are coupled in a bolt-coupled manner to complete the coupling operation. On the other hand, the disassembly of the detachable vertical motion reduction device 1 can be performed in the reverse order of the above-described combination order.

As described above, according to the present embodiment, since the lifting guide member connected to the semi-submergible structure is connected to at least one of the truss unit and the hive plate, the lifting guide member can be coupled in a lifting manner underwater, Since the vertical motion reduction device is supported by the lifting guide member even when the vertical motion reduction device is dismantled, the maintenance and repair can be performed conveniently and stably.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the invention. Accordingly, such modifications or variations are intended to fall within the scope of the appended claims.

1: detachable vertical motion reduction device 100: truss unit
110: truss leg 111: first flange
120: truss reinforcing member 130: interference preventing member
200: Hive plate 210: Base plate
211:
220: extension plate 300: lifting guide member
400: Gader 500: Stopper
600: semi-submerged structure 610: deck
620: Column 630:
631: second flange C: chain member
F: Fixing member PE: Pad Eye
W: Winch

Claims (15)

A truss unit detachably connected to the semi-submerged structure;
A heave plate coupled to the other side of the truss unit to reduce vertical motion of the semi-submergible structure; And
And a lifting guide member connected to at least one of the truss unit and the hive plate to guide lifting of the semi-submergible structure when the truss unit is coupled to the semi-submergible structure. Removable vertical motion reduction device. The method according to claim 1,
The truss unit includes:
And a plurality of truss legs having a first flange at one side and coupled to a second flange provided at a lower side of the semi-submergible structure in a bolt-coupled manner. The method of claim 2,
Wherein each of the plurality of truss legs is provided with two pairs, each pair of the truss legs being arranged to be mutually symmetrical in the longitudinal direction of the semi-submergible structure with respect to the center of the semi-submergible structure. Abatement device. The method of claim 2,
The truss unit includes:
Further comprising a plurality of truss reinforcement members interconnecting the plurality of truss legs to reinforce the plurality of truss legs. The method of claim 2,
Wherein the lifting guide member connected to the truss unit is disposed inside the plurality of truss legs,
The truss unit includes:
Further comprising an interference preventing member provided inside the plurality of truss legs to prevent interference between the lifting guide member and the inner wall of the plurality of legs. The method according to claim 1,
Wherein the hive plate includes a base plate having a plurality of holes coupled to the other side of the truss unit and serving as drainage passage for seawater. The method of claim 6,
Wherein the base plate is provided with a moonpool. The method of claim 7,
Wherein the plurality of holes
A plurality of small holes provided on both sides of the base plate in the longitudinal direction of the door frame; And
And a plurality of large holes provided in a region of the base plate excluding both sides in the longitudinal direction thereof and having a larger diameter than the plurality of small holes. The method of claim 6,
Wherein the heave plate further comprises a plurality of extension plates provided in the longitudinal direction of the base plate. The method according to claim 1,
Wherein the lifting guide member comprises a chain. The method according to claim 1,
Wherein the lifting guide member is connected to the semi-submergible structure to support the truss unit when the truss unit is separated from the semi-submerged structure. The method according to claim 1,
A guider provided on the semi-submergible structure for guiding the lifting and guiding of the lifting guide member; And
Further comprising a stopper provided on the semi-submergible structure for stopping the lifting guide member. The method of claim 12,
The semi-
Deck;
A plurality of columns coupled to an upper portion of the deck to support the deck; And
And a plurality of pontoons coupled to a lower portion of the plurality of columns to support the plurality of columns and to which the truss unit is detachably coupled.
1. A vertical motion reduction apparatus for a semi-submergible structure, comprising a heave plate for reducing vertical motion of a semi-submergible structure and a truss unit for connecting the heave plate to the semi-submergible structure,
Wherein the truss unit is lifted by a lifting guide member connected to at least one of the truss unit and the hive plate and is detachably coupled to the semi-submergible structure. 15. The method of claim 14,
Wherein the lifting guide member connected to the truss unit is disposed inside the truss unit.

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