KR20110045299A - Operating process for ship or offshore structure with derrick in low COG condition - Google Patents

Abstract

PURPOSE: A method of operating a ship or an offshore structure with a drilling derrick in a low-cog state is provided to enhance buoyant stability by lowering the COG(Center of Gravity) of a ship since a derrick is folded during the sailing of the ship. CONSTITUTION: A method of operating a ship or an offshore structure with a drilling derrick in a low-cog state is as follows. A derrick is carried in a state of being folded by a support on a ship or a barge(50). When the derrick is carried, the upper part of the derrick can be downwardly folded. The COG of the offshore is lowered by supporting the folded derrick using the support. The foldable drilling derrick is installed on the ship or offshore structure. The COG of the ship or offshore structure can be lowered by maintaining the derrick in a folded state while the derrick does not perform a drilling operation.

Description

Operating process for ship or offshore structure with derrick in low COG condition}

The present invention relates to a method of operating a ship or offshore structure in which a drilling derrick is installed at a low center of gravity (COG). In particular, the invention relates to a method of increasing the operational stability of a ship or offshore structure by folding down the top of the derrick when transporting the derrick or when operating a ship or offshore structure equipped with a drilling derrick.

As the international rapid industrialization and industry develop, the use of global resources such as petroleum is gradually increasing, so that stable production and supply of oil is becoming a very important problem at the global level.

For this reason, the development of marginal oil fields and deep-field oil fields, which have been neglected until recently, have become economic. Therefore, along with the development of seabed mining technology, a drilling vessel equipped with drilling equipment suitable for the development of such an oil field has been developed.

Conventional subsea drilling is mainly used for rig ship or fixed platform dedicated to subsea drilling, which can be sailed only by other tugboats and anchored at one point of the sea using mooring devices. Recently, so-called drill ships, which are manufactured in the same form as general ships so that they can be sailed by their own power and equipped with advanced drilling equipment, have been developed and used for subsea drilling.

In the center of a rig ship or a drilling ship (hereinafter referred to as a drilling ship) equipped with various drilling equipments to drill oil or gas existing in the basement of the seabed, a riser for drilling oil or gas existing in the basement of the seabed Or a moonpool is formed so that a drill pipe can be moved up and down.

1 is a side view showing a conventional drilling vessel performing drilling operation at sea level.

The operator moves the riser 4 and the drill pipe 5 downward through the door pool 3 formed in the center of the drilling rig to the reservoir 12 located below the sea bed 6. (well) Drill undersea resources stored in (13).

The riser 4 provides a passage through which the mud returns as a member that is advanced to the bottom of the sea floor 6 before advancing the drill pipe 5 to the well 13. When the riser 4 is installed, the drill pipe 5 is advanced downwardly into the well 13 through the subsea layer 11 into the riser 4.

As described above, when the riser 4 is advanced downward to the sea bottom 6 or the drill pipe 5 is advanced to the oil well 13, it is necessary to advance the riser 4 or the drill pipe 5 connected long. Rather, the short riser 4 or the drill pipe 5 are connected to each other and advanced downward. A blowout preventer (BOP) 7 is provided at the sea bottom 6 to prevent abnormal high pressure from riding up the drill pipe 5. In the subsea bed 11, the casing 8 is fixed by cement, and then the seabed resources are drilled by inserting the drill pipe 5 equipped with the drill bit 10 into the casing. The mud 9 is inserted into the drill pipe 5 to prevent the drill bit 10 from overheating by the heat generated when the drill bit 10 drills the ground and to lubricate to make drilling easier. do. This mud exits through the drill bit 10 and back through the casing 8 and riser. When the drilling operation is completed, the drill pipe 5 is transported to the drill floor through the door pool 3, separated, and then transported to the loading site.

2 is a diagram illustrating a conventional derrick structure.

The conventional drilling line includes an upper deck 21 and a drill floor 22 positioned above the upper deck 21, and the drill floor 22 is provided with a derrick 20. The drill pipe 5 stacked horizontally in the pipe loading space is erected and gripped by the top drive 23 and the rotary table 24. After the two or more drill pipes 5 are joined together, the combined drill pipes are temporarily loaded vertically in the setback area and then advanced downward through the door pool during drilling.

In general, the derrick 20 is a trust tower made of steel, the height is about 100m, depending on the design.

The conventional derrick has a complex steel structure, the manufacturing method is a manufacturing process is cumulative from the bottom to build a complicated manufacturing process and this is a time-consuming problem, and also required a lot of crane maneuver cost was expensive .

In addition, the recent derrick has become very large, it has been a lot of problems to transport it as a finished product assembled outside the ship or offshore structures to which the derrick is mounted. However, in recent times, each shipyard is a problem because there is a lack of space inside the necessity of assembling the derrick from the outside.

Also, on drilling ships, derricks are large structures that are usually over 100 meters tall. When a drilling ship passes airways subject to air draft limits, such as the Centennial Bridge across the Panama Canal, the Murabask Peacebridge across the Suez Canal, and the Bosphorus Strait Bridge, Derrick passes due to its height. There are cases where this is impossible. In addition, since the height of the derrick is more than 100m, the derrick installed on the drilling ship increases the center of gravity (COG) during the voyage of the ship, which is a factor that hinders the floating stability.

Accordingly, the present invention has been invented in view of the above circumstances, and by allowing the derrick to be folded, it is possible to allow passage in a route to which the maximum height limit is applied, such as a canal, thereby reducing the time and cost required for ship operation. In addition, the object of the present invention is to provide a derrick structure in which the center of gravity (COG) is increased and the stability is improved.

In addition, an object of the present invention is to solve the problems of the prior art, and the object of the present invention is to provide a manufacturing method of a derrick for ships or offshore structures, the manufacturing process of which is simple and takes less time.

In addition, it is an object of the invention to provide a transport and manufacturing method of the derrick for ships or offshore structures that solves the problems caused by moving a large sized derrick.

According to an embodiment of the present invention, in the method of operating a ship or offshore structure equipped with a drilling derrick, the drilling derrick is characterized in that the upper portion can be folded, when not drilling the drilling derrick There is provided a method of operating a vessel or offshore structure with a drilling derrick installed in a low state of backwater, characterized in that to keep the derrick in a folded state to lower the seagull (COG) of the vessel or offshore structure. Preferably, when not drilling by the drilling derrick means that the vessel or offshore structure is in motion.

According to another embodiment of the present invention,

In the method of carrying the drilling derrick,

Loading the drilling derrick onto the ship or barge,

Folding the top of the drilling derrick, supporting the folded derrick with a support supported on the vessel or barge,

Transport the vessel or barge to the destination;

There is provided a method of transporting a derrick, characterized in that to unload the derrick.

The upper derrick is composed of the upper left derrick and the upper right derrick adjacent to the left upper derrick, the lower derrick is located below the left and right upper derrick, the left and right upper derrick When the left upper derrick and the upper right derrick are rotated left and right, respectively, when the left upper derrick and the upper right derrick are folded on the lower derrick, they are seated on a support on a drill floor, thereby folding a ship's derrick such as a drilling line. By constructing, it is desirable that the height of the derrick is lowered and the center of gravity is lowered. In addition, the support is preferably attached detachably.

According to another embodiment of the present invention,

In a ship equipped with a drilling derrick on a floor, the drilling derrick

The upper left derrick;

An upper right derrick adjacent to the left upper derrick;

Consists of a lower derrick positioned below the left and right upper derrick,

The left and right upper derrick are hinged rotatably from side to side on the lower derrick, and when the left upper derrick and the right upper derrick are rotated left and right, respectively, they are seated on a support on a drill follower, such as a drilling line. By constructing the ship's derrick structure, the height of the derrick is lowered and the center of gravity is lowered to provide a ship equipped with a low sea back derrick, characterized in that the floating stability is improved.

The support is preferably attached detachably. In addition, the left and right upper derrick is preferably driven by a hydraulic cylinder, respectively.

According to another embodiment of the present invention,

In the manufacturing method of the drilling derrick consisting of a trust structure,

Forming a left and right preassembly of the lower derrick in a first location;

Forming a left and right preassembly of the upper derrick in a first location;

Transporting the preassembly to a second place where the preassembly is assembled;

Provided are a method of transporting and manufacturing a drilling derrick for a ship or offshore structure comprising the step of assembling the transported preassembly in a second location.

According to another embodiment of the present invention,

In the manufacturing method of the drilling derrick consisting of a trust structure,

Forming a left and right preassembly of the lower derrick in a first location;

Forming a left and right preassembly of the upper derrick in a first location;

Transporting the preassembly to a second place where the preassembly is assembled;

There is provided a method of manufacturing a drilling derrick for a ship or offshore structure comprising the step of assembling the conveyed preassembly at a second location.

Preferably, the second place is characterized in that on or adjacent to the marine structure or the vessel on which the derrick is mounted,

In addition, the left and right pre-assemblies of the lower derrick, forming a left outer skeleton and a right outer skeleton, respectively; Stacking materials constituting the internal trust on the left and right outer skeletons of the lower derrick by bolting to form left and right preassemblies of the lower derrick; and

The left and right preassemblies of the upper derrick may include forming a left outer skeleton and a right outer skeleton of the upper derrick, respectively; And stacking the materials constituting the internal trust on the left and right outer skeleton of the upper derrick by bolting up to form the left and right preassemblies of the upper derrick.

According to still another embodiment of the present invention, in the method for manufacturing a drilling derrick having a trust structure,

Forming a left outer skeleton and a right outer skeleton of the lower derrick, respectively;

Stacking materials constituting the internal trust on the left and right outer skeletons of the lower derrick by bolting to form left and right preassemblies of the lower derrick;

Erecting the left and right pre-assemblies of the lower derrick to an assembly position using a crane, respectively;

Assembling the thrust material adjacent to the inside of the standing lower left and right preassembly to complete the lower derrick;

Forming a left outer skeleton and a right outer skeleton of the upper derrick, respectively;

Stacking materials constituting an internal trust on the left and right outer skeletons of the upper derrick by bolting to form left and right preassemblies of the upper derrick;

Erecting the left and right pre-assemblies of the upper derrick to each assembly position using a crane;

Assembling the thrust material adjacent to the inside of the upright left and right preassembly to complete the upper derrick;

Placing the completed upper derrick on the completed lower derrick to an assembly position using a crane, and assembling upper and lower derricks to complete the derrick;

There is provided a method of manufacturing a drilling derrick for ships or offshore structures.

In order to facilitate the mutual assembly of the left and right preassemblies of the upper and lower parts, it is desirable to prepare bolting holes in advance in the material of the adjacent trust inside the preassembly.

In addition, the mutual assembly of the left and right pre-assembly is preferably fixed to the outside of the left and right pre-assembly in advance of the material interconnecting them, and then assembled by bolting the adjacent materials therein.

According to the present invention, the conventional derrick has a complex steel structure, the manufacturing method is a manufacturing process is cumulatively stacked from the bottom in order to produce a complex and this is a problem that takes a lot of time, and also because the required number of cranes In addition to the cost, the present invention not only has the advantages of a simple manufacturing process and requires less time, but also enables the manufacture of highly accurate derricks.

In addition, according to the present invention there is provided a manufacturing method of the derrick for ships or offshore structures to solve the problems caused by moving the large derrick.

In addition, it is possible to fold the derrick during sailing of the ship to lower the center of gravity of the ship can be improved floating stability.

In addition, in the present invention, when carrying the derrick, the upper part of the derrick is folded down, and by supporting the folded derrick with the support lowers the center of gravity and improves the stability of the built derrick at the same time to increase the stability of the derrick or It can also be transported by barge.

Hereinafter, the configuration and operation of the preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

According to one embodiment of the invention the manufacturing method of the drilling derrick according to the present invention is as follows.

First, assemble the lower derrick. The assembly of the lower derrick separates the left and right sides to form a preassembly, respectively.

The formation of each preassembly forms a lower left outer skeleton and a right outer skeleton, respectively. The materials constituting the inner trust of the outer skeleton are then piled up by bolting to complete the upper left and right preassemblies. 3 is a view showing the outer skeleton of the upper and lower derrick during the manufacturing process of the drilling derrick of the present invention, Figure 4 is a view showing an internal trust formed on the outer skeleton of the derrick of FIG. 4 shows the left preassembly.

When the formation of the preassembly of the lower left and right derrick is completed, the upper derrick is assembled. Assembly of the upper derrick is also separated from the left and right to form a pre-assembly, respectively.

Each assembly first forms an upper left outer skeleton and a right outer skeleton respectively. The materials constituting the inner trust of the outer skeleton are then piled up by bolting to complete the upper left and right preassemblies.

Completion of the left and right preassemblies of the upper derrick may be performed after assembling the left and right preassemblies of the lower derrick to each other to complete the assembly of the lower derrick.

When the formation of the left and right pre-assembly of the upper and lower derrick is completed as described above is completed assembly. These assembly is performed using two cranes. First, the left and right preassembly of the lower part is erected to the assembly position using a crane. Subsequently, the left and right preassembly of the lower part is assembled by bolting adjacent thrust materials adjacent thereto.

In order to facilitate the mutual assembly of the left and right preassemblies, it is desirable to prepare bolting holes in advance in the material of the adjacent trust inside the preassembly. In addition, after fixing in advance with a material connecting to the outside of the left and right pre-assembly, it is preferable to assemble the adjacent material in the inside by bolting.

As above, once the assembly of the lower preassembly is completed, assembly of the left and right preassembly of the upper derrick is then started on top of the lower derrick.

First, the left and right derricks of the upper derrick are raised on the upper part of the lower derrick by using a crane, and then the upper left and right preassembly is erected according to the assembly position. The upper left and right preassembly is then assembled by bolting the adjacent trust material therein.

 In addition, it is preferable to complete the derrick by assembling the upper and lower derricks by assembling the left and right preassemblies of the upper derrick to each other to complete the upper derrick. This will increase the precision of the derrick.

In order to facilitate the assembly of the preassembly, it is desirable to prepare bolting holes in advance in the material of the adjacent trust inside the preassembly. In addition, it is preferable to assemble the adjacent materials inside by bolting after fixing in advance to the outside of the left and right preassembly with materials interconnecting them. Furthermore, in the case where the pre-assembly of the upper derrick is placed on the lower derrick, it is preferable to form a protruding member in the lower part of the upper derrick, and an insertion hole into which the protruding member is insertable in the upper part of the lower derrick. In this way, the precision of the derrick can be increased.

According to yet another embodiment of the present invention, the upper and lower left and right preassemblies are respectively manufactured in a first place, and then the preassembly is transported to a second place, and the preassemblies are mutually assembled in a second place. Provided is a method of manufacturing a derrick for completing a drilling derrick for offshore structures or for ships. 5 illustrates a manufacturing process of a derrick according to an embodiment of the present invention.

Completion of the pre-assembly in the first place, the left and right pre-assembly of the upper and lower parts may be carried separately and four separately, if the derrick is small, each left and right pre-assembly is completed Each of the upper and lower derricks can be transported separately.

The second place is actually a place on or adjacent to the ship or offshore structure, and the derrick completed by assembling the pre-assembly directly on the ship or offshore structure, or by assembling the pre-assembled body on the adjacent place. The crane can be mounted on a ship or offshore structure to mount a derrick.

The pre-assembly can be transported on land if its size is not large, but it must be transported by sea if its size is large. Barges can be used for sea transport. When transporting by sea by barge, the pre-assembly may be shipped to the barge at the first location by crane, but using the conventional load-out method of large structures, i.e. using bogies and skid rails. Sliding is available on the way.

By doing so, there was a problem in the conventional transport of the large derrick, the present invention has a technical significance to solve this problem.

6 to 8 is a view showing an embodiment of folding the derrick in a folded derrick structure for ships as another embodiment according to the present invention.

In this embodiment, the derrick is installed on a drill floor 30. The upper derrick consists of a left upper derrick 31 and a right upper derrick 32. Below the lower derrick 40 is located.

The left hydraulic cylinder 35 is installed on the left upper derrick 31. The left hydraulic cylinder 35 is coupled to the lower derrick 40 at the hinge point 35a.

The right hydraulic cylinder 36 is installed on the right upper derrick 32. The right hydraulic cylinder 36 is coupled to the lower derrick 40 at the hinge point 36a.

As the left hydraulic cylinder 35 is extended, the upper left derrick 31 rotates around the hinge coupler 38 and is folded down to the left. As the upper left derrick 31 rotates, the left hydraulic cylinder 35 is also extended and rotated about the hinge point 35a.

The support 42 is detachably attached to the drill floor 30 in the vicinity of the lower derrick 40 to stably support the fully folded left upper derrick 31.

When the left upper derrick 31 is folded, at the same time, the upper right derrick 32 is also rotated and folded around the hinge coupling portion 38 in the same manner as the left upper derrick 31.

The process of setting up the left and right upper derricks 31 and 32 which have been folded is performed by contracting the left and right hydraulic cylinders 35 and 36. At this time, the left and right upper derrick (31, 32) is rotated and built around the hinge coupling portion 38, and the left and right hydraulic cylinders (35, 36) are also set up around the hinge points (35a, 36a), respectively. You lose.

In the present embodiment, the left and right upper derricks 31 and 32 are supported by the left and right hydraulic cylinders 35 and 36 and fold in accordance with the elongation of the left and right hydraulic cylinders 35 and 36. The folding operation of the upper right derrick (31, 32) is made in a stable and very simple way. In addition, the folding and returning of the upper derrick can be made very quickly. In addition, the left and right upper derrick has a merit that is stably supported by the support 42 installed on the drill flower in a completely folded state.

As described above, by constructing the structure of the ship's derricks, such as drilling ships, the height is lowered and the center of gravity is lowered, not only convenient for the ship to pass through the canal, but also lower the center of gravity when operating in the sea to improve the stability of the float Can be.

9 is a view showing an embodiment of transporting the folded derrick by ship or barge as another embodiment according to the present invention.

In this embodiment, the derrick may be transported in a folded state by a support installed on the ship or barge 50. Conventionally, the derrick can only be transported in a lying state due to the height of 100m or more, in this case there was a problem that requires a very long barge. If you want to carry the derrick upright, its height is so high that it not only raises the COG but also makes it hard to stand on the barge. In the present embodiment, when carrying the derrick, the upper part of the derrick is folded down, and by supporting the folded derrick using a support lowering the center of gravity and at the same time can improve the stability of the derrick.

In another embodiment of the present invention, the drilling derrick, which can be folded as described above, is installed on a ship or offshore structure and actually operated, the drilling derrick is characterized in that the upper portion can be folded, and the drilling derrick When not drilling, the derrick can be kept in a folded state to lower the COG of the vessel or offshore structure. When the drilling derrick is used, it should be used upright, but when the drilling derrick is not drilling, for example, when a ship or offshore structure is moving, or when a worker cannot be made due to wind, the ship is folded and the ship or offshore structure The center of gravity of the can be lowered to improve their stability at sea.

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 and scope of the invention will be.

1 is a side view showing a conventional drilling ship performing drilling operation at sea level.

2 is a view showing the structure of a conventional derrick.

3 is a view showing the outer skeleton of the upper and lower derrick during the manufacturing process of the drilling derrick of the present invention.

4 shows an internal trust formed on the outer skeleton of the derrick of FIG. 3;

5 is a view showing a manufacturing process of the derrick according to an embodiment of the present invention.

6 to 8 is a view showing a folded derrick structure for ships as another embodiment according to the present invention.

9 is a view showing the transport of the folded derrick in a ship or barge according to the present invention.

<Explanation of symbols for the main parts of the drawings>

3: moonpool

4: riser

5: drill pipe

7: BOP

20: Derek

21: upper deck

22: drill floor

30: Drill Follower

31: Upper left derrick

32: upper right derrick

35, 36: left and right hydraulic cylinders

35a, 36a: left and right hydraulic cylinders

40: Lower Derrick

42: support

38: hinge coupling

50: shipping or barge

Claims (2)

In the method of operating a ship or offshore structure equipped with a drilling derrick, The drilling derrick is characterized in that the top can be folded, When the drilling derrick is not drilling, the ship or offshore structure with the drilling derrick, characterized in that to keep the derrick folded state to lower the COG of the vessel or offshore structure. How to drive in low conditions. 2. The method of claim 1, wherein when the drilling derrick is not drilling, the vessel or offshore structure is in motion when the ship or offshore structure is in motion. 3.

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