KR101681712B1 - Offshore structure having an ubd system - Google Patents

Abstract

An offshore structure having a UBD system is disclosed. An offshore structure provided with the UBD system of the present invention includes a deck; And a UBD system provided in the deck for testing and separating the well cutting wells of drilled wells using drilling fluids designed to a pressure lower than the pressure of the seabed that is the subject of drilling.

Description

BACKGROUND OF THE INVENTION [0001] The present invention relates to an offshore structure having an UBD system,

The present invention relates to an offshore structure having a UBD system, and more particularly, to an offshore structure having a UBD system using a drilling fluid designed to have a pressure lower than that of a seabed layer to be drilled.

The depth of the oil field currently under development is gradually shifting to deep sea. In order to develop oilfields, drilling operations should be preceded by confirmation of the oil stores, and the depth of drilling is also shifting to deep sea due to the trend of oil field development.

Drilling-ship, drilling-rig, jack-up, and drilling-barge are examples of marine structures that perform drilling operations. Among these, Drill-ship and Drilling-Rig are available for deep drilling.

The drill ship is a ship type drill ship, which has the advantage of being able to work for a long time without the help of a supply vessel because of the large loading space. However, due to the disadvantage of poor performance due to the ship type, the input is limited in the sea area where the sea environmental load due to waves and the like is high.

Drilling rigs are also called semi-submersible. Semi-submersible is composed of column and pontoon, and it has good merit because of small repair area. Therefore, it is possible to input even in the sea area where the marine environmental load is relatively high, and it is putting a lot of effort into the development of the deep sea oil field.

On the other hand, the above-described marine structure with drilling rig uses a drilling fluid having a pressure higher than that of the seabed layer when forming the well in the seabed. In this case, since the pressure in the hole is higher than the pressure in the seabed layer, the pressure difference causes the oil or gas to flow from the hole into the seabed layer, resulting in loss of oil or gas.

In addition, damage may occur near the hole in the course of oil or gas being introduced into the seabed layer due to the pressure difference described above. Especially, the pressure of the hole is higher than that of the seabed so that the pressure of the hole pushes the drill pipe to the subsoil and sticks to the subsoil (differential sticking). In this case, it is almost impossible to separate the drill pipe from the seabed.

Furthermore, a loss of the drilling fluid occurs due to the pressure difference between the seabed layer and the de-ringing fluid. That is, there is a problem that the expensive mud which is a drilling fluid is sucked into the seabed layer due to the pressure difference to form a mud cake, thereby wasting the mud.

Korean Patent Registration No. 10-0231802 (Daewoo Corporation) 1999. 09. 01

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide an offshore structure equipped with a UBD system capable of efficiently performing drilling operations by controlling a pressure difference between a seabed layer and a drilling fluid and having an efficient spatial arrangement.

According to an aspect of the present invention, there is provided a lithographic apparatus comprising: a deck; And a UBD system provided in the deck for testing and isolating the well cutting flow of the drilled well using a drilling fluid designed to a pressure lower than the pressure of the seabed that is the subject of drilling .

The UBD system may include a well test separation unit provided on the deck of the aft section of the hull to separate a well cutting stream supplied in the test process of the well cutting stream.

The UBD system may include a nitrogen generating unit that is provided in the deck of the aft area of the hull and produces the nitrogen supplied to the drilling fluid such that the drilling fluid has a pressure lower than the pressure of the seabed.

The nitrogen generating unit may be installed in the platform separately provided in the deck and having at least one rail on the ceiling.

The UBD system may include a separation unit provided in the deck region between the forward portion of the hull and the aft portion to separate the separating material including the cutting water and the drilling fluid from the well cutting stream.

The UBD system may include a hammer mill unit provided on the deck of the aft section of the hull, for separating the solid contained in the well cutting stream into a separated product including oil and liquid.

The UBD system may include a triple cabin and a tool house provided in the deck area between the forward and aft portions of the hull and having an approach path.

The UBD system may include a cementing unit that is provided in a cementing room of the forward portion of the hull and supplies cement to cement the drilled well.

The offshore structure may include a drill ship, drilling rig, jack-up rig or drilling pants.

Embodiments of the present invention can perform effective drilling work by adjusting the pressure difference between the seabed layer and the drilling fluid, and can efficiently perform spatial arrangement.

FIG. 1 is a view schematically showing an underbalanced drilling (UBD) to which the present embodiment is applied and conventional drilling.
2 is a side view schematically showing an offshore structure having the UBD system according to the present embodiment.
FIG. 3 is a schematic view showing a well test separation unit, a nitrogen production unit, a partial separation unit, and a hammer mill unit in a stern part of a marine structure provided with the UBD system shown in FIG.
4 is an enlarged arrangement view of the nitrogen generating unit shown in Fig.
5 and 6 are enlarged arrangement views of the separation unit.
7 is an enlarged arrangement view of the hammer mill unit shown in Fig.
FIG. 8 is an enlarged layout plan view of a cement unit in an offshore structure having the UBD system shown in FIG. 2. FIG.
FIG. 9 is an enlarged layout of a triple cabin and a full house in an offshore structure having the UBD system shown in FIG. 2; FIG.

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.

FIG. 1 is a view schematically showing an underbalanced drilling (UBD) to which the present embodiment is applied and conventional drilling.

The present embodiment is characterized in that as shown in Fig. 1 (a), UBD (drilling) is performed using a drilling fluid P ₂ designed at a pressure lower than the pressure P ₁ of the seabed layer to be drilled in the ocean, .

In conventional drilling, the pressure of the mud, which is a drilling fluid, is designed to have a water pressure that is 200 to 1000 psi higher than the pressure of the seafloor. Thus, as shown in 1 (b), the pressure of the subsea strata (P1) is a lower drilling fluid than the pressure (P ₂₎ of the drilling fluid is flowing into the sea floor resin layer, such as a loss of drilling fluid takes place above Problems arise.

However, this embodiment utilizes a UBD drilling with a drilling fluid pressure lower than the pressure of the seabed layer by 100-200 psi, so that the solid or drilling fluid does not flow into the well-formed seabed layer, and the damage of the seabed layer is reduced.

As soon as the drill bit is drilled in the well, the fluid such as crude oil is immediately raised by the pressure difference, so that the fluid stored in the well can be produced early. Furthermore, UBD does not apply pressure in the direction of the seabed so that differential sticking of the drill pipe to the seafloor during drilling is avoided.

In particular, since no pressure is applied in the direction of the seabed layer, the cost of the expensive mud is reduced, the penetration rate is increased, the penetration speed is increased, and the effective removal of the cut material from the drill bit face portion increases the life of the drill bit, Can be significantly reduced.

On the other hand, nitrogen and natural gas are supplied to the mud to design the pressure of the drilling fluid to be lower than the pressure of the seafloor. Hereinafter, the drilling fluid includes nitrogen contained in the mud, and the wellcutting term includes crude oil, gas, drilling fluid, solid cutting water, etc., and the offshore structure is referred to as a drill ship Explain.

2 is a side view schematically showing an offshore structure having the UBD system according to the present embodiment.

As shown in this figure, an offshore structure 1 according to the present embodiment comprises a deck (deck), a deck (D), and a drilling And a UBD system for testing and separating the well-cutting flow of drilled wells using fluid.

As shown in FIG. 2, the UBD system includes a well test separation unit 100 provided on a deck D of a stern area of a hull to separate a well cutting stream supplied in a test process of a well, A nitrogen generating unit 200 provided in the deck D of the zone and generating nitrogen supplied to the drilling fluid such that the drilling fluid has a pressure lower than the pressure of the seabed layer; A separating unit (300) provided on the deck (D) of the stern area of the hull to separate the solids contained in the well cutting stream, the separating unit A cementing unit 500 for supplying cement to the drilling wells provided in the cementing room of the forefront region of the hull and supplying the cement to the drilled wells; With the athletes It provided on the deck (D) the area between the tail and includes a triple cabin 600 and the tool house 700 having an access path (800).

The well test separation unit 100 separates the well cutting flow supplied in the well test process. As shown in FIGS. 2 and 3, the well test separation unit 100 includes various equipment including drilling equipment, In order to secure an effective space in the ship's stern area.

In the present embodiment, the well test separation unit 100 includes a well test separator 110 for separating the well cutting stream transferred from the well into cutting oil, gas, water, and solid, as shown in FIG. 3, An oil separator 120 for separating oil from the water separated and supplied from the well test separator 110, an oil separator 120 provided in the line to which the well-cutting flow is supplied, and the temperature of the well- A surge tank 140 for storing separated liquid hydrocarbons and a transfer pump 150 for pumping liquid hydrocarbons stored in the surge tank 140 to a burner or the like, And a first control cabin (160).

The well test separator 110 of the well test separating unit 100 is disposed so as to be urged to a crane C provided at the lateral edge of the deck D as shown in Fig. And a vertical well test separator 112 for secondary separation of the well cutting flows separated in the horizontal well test separator 111. The vertical well test separator 111 is provided with a vertical well test separator 111, The installation area can be reduced.

In this embodiment, the well test separator 110 includes a first separator, a second separator for separating the well cutting flow by gravity, a mist extractor for removing small liquid particles from the gas, And a liquid separator for removing gas or vapor.

The nitrogen producing unit 200 produces nitrogen supplied to the drilling fluid such that the drilling fluid is provided at the stern of the hull where the drill pipe is to be loaded, such that the drilling fluid has a pressure lower than the pressure of the seabed layer

4, the nitrogen generating unit 200 includes a nitrogen generator 210 for generating nitrogen, a booster for increasing the pressure of nitrogen generated in the nitrogen generator 210 to a required pressure, A booster compressor 220, an air compressor 230 for supplying compressed air to the booster compressor, a nitrogen generator 210, a booster compressor 220 and an air compressor 230, And a first platform 240 for providing a space for loading a spider (S, spider), gimbals (G, gimbal), and the like.

4, the first platform 240 includes a plurality of first vertical members 241 provided on the upper side of the deck D, a plurality of first vertical members 241, A first ceiling plate 242 coupled to an upper end of the first ceiling plate 242 and at least one of a first ceiling plate 242 and a second ceiling plate 242 disposed inside the first ceiling plate 242 for pulling the hoist trolley HT to facilitate the movement and installation of the nitrogen generator 210, And a first rail 243 of the first rail 242.

The present embodiment is characterized in that the nitrogen generator 210 and the like are not exposed to the external environment even when the rain or the like is turned on by the first platform 240 and the nitrogen generator 210 and the like are driven by the hoist There is an advantage that it can be conveniently moved and installed by the trolley (HT).

In addition, the spider S, the zoom ball G, and the like can be mounted on the upper side of the first ceiling plate 242, thereby enhancing the space efficiency.

The separation unit 300 is for separating the well cutting stream supplied from the drilling operation after the well test is finished. As shown in FIG. 2, the separation unit 300 includes a plurality of well cut- And a deck (D) area between the stern section.

2, the separation unit 300 includes a first separation unit 310 disposed at a position offset toward the stern of the hull and separating a sample of a cutting flow from a supplied well cutting stream, And a second separation unit 320 disposed at a central region between the forward portion and the aft portion of the hull and separating the cutting flow from the supplied well cutting stream.

As shown in FIGS. 3 and 5, the first separation unit 310 of the separation unit 300 includes a choke manifold 311, which is an inlet pipe for drilling fluid, and a choke manifold 311, A sample catcher 312 for separating a cutting flow as a sample to be introduced from an incoming well cutting flow and a flow rate measuring device for measuring a flow rate of a well cutting stream supplied to a channel connecting the choke manifold 311 and the sample catcher 312 A second control cabin 314, a choke manifold 311, a sample catcher 312, a Coriolis flowmeter 313, and a second control cabin 314, A second platform 315 for providing a space for loading a telescopic joint, a pup joint or the like to the first control cabin 314 and a second platform 315 for providing a space for loading a telescopic joint, (Not shown).

5, the second platform 315 includes a plurality of second vertical members 315a provided on the upper side of the deck D, and a plurality of second vertical members 315a provided on the upper side of the deck D, A second ceiling plate 315b which is coupled to the upper end of the second ceiling plate 315b and at least one of the first ceiling plate 315b and the choke manifold 311, And a second rail 315c.

The second platform 315 prevents the choke manifold 311 and the like from being exposed to the outside environment even when the choke manifold 311 or the like is exposed to rain or heavy snow, And can be conveniently moved and installed by the hoist trolley HT supported by the second rail 315c.

Further, a telescopic joint (TJ), a pub joint (PJ), or the like can be mounted on the upper portion of the second ceiling plate 315b, thereby improving space efficiency.

The second separation unit 320 of the separation unit 300 separates the well cutting stream supplied through the choke manifold 311 without passing through the sample catcher 312, A centrifugal separator 321 for separating most of the well cutting fluid supplied from the centrifugal separator 321 by a centrifugal force in the solid state, a cutting dryer 322 for drying the cutting fluid in the solid state separated from the centrifugal separator 321, A cutting blower 323 that feeds the cutting fluid separated by the separator 321 to an ISO pump 324 to be described later and an ISO pump 322 that feeds the cutting air supplied from the cutting blower 323 to the supply source 324).

In this embodiment, the cutting blower 323 includes a pressure vessel main body having an inlet valve and an outlet valve, and a feed hopper which is provided at an upper side of the pressure vessel main body and into which a cutting flow flows, Is discharged by compressed air.

As shown in FIGS. 2 and 3, the hammer mill unit 400 is provided on the deck D of the stern area of the hull so as to crush a solid included in the well cutting stream, It separates into water.

The well cutting stream supplied to the hammer mill unit 400 in this embodiment may be supplied via the separation unit 300 or the well test separation unit 100 and may be supplied via the choke manifold 311 to the separation unit 300. [ May be supplied directly without passing through the test test separation unit 300 and the well test separation unit 100.

7, the hammer mill unit 400 includes a hopper 410 in which a well cutting flow supplied through a choke manifold is stored, a hopper 410 which is supplied with a well cutting stream supplied from the hopper 410, A hammer mill 420 which is driven by the drive motor 430 to crush the contained solid material into fine particles and a solid particle mixed in the fluid by centrifugal force in a well cutting stream supplied from the hammer mill 420 except for fine particles An oil condenser 450 for absorbing heat from the well cutting stream supplied from the cyclone 440 and using oil as a coolant, and a condenser 450 for cooling the oil condenser 450 A steam condenser 460 for cooling the well cutting stream with steam and a separator 470 for separating the well cutting stream supplied from the steam condenser 460 into oil and water.

The hammer mill 420 of the hammer mill unit 400 includes a rotor rotated by a driving motor 430 and a well cutting stream supplied to the hammer mill 420 is rotated by fine particles In this process, the oil and water contained in the well-cutting stream are evaporated by the heat generated by the friction.

7, the hammer mill unit 400 includes an oil scrubber 480 provided between the cyclone 440 and the oil condenser 450 to remove volatile compounds from the well cutting stream, A demister 490 provided between the oil condenser 450 and the steam condenser 460 for removing mist and a storage tank T for storing fine particles pulverized by the hammer mill 420. P is a pump.

The cementing unit 500 is provided in the cementing room of the forward region of the hull as shown in Fig. 2, and supplies cement to cement the drilled well. As shown in Fig. 8, A cement mixer 510, a cement unit 520 for pumping the mixed cement in the cement mixer 510, a slurry remover 530 for removing the slurry present in the mixed cement pumped in the cement unit 520, .

8, the cement unit 520 includes a cement pump 521 for pumping the mixed cement supplied from the cement mixer 510, a cement pump 521 for providing a pumping force to the cement pump 521, .

In the present embodiment, the cementing unit 500, as shown in FIG. 8, is configured such that when the pressure is suddenly changed in the pipe through which the mixed cement supplied with the slurry removed from the slurry removing unit 530 is fed, And a cement surge tank 540 for protecting the piping and the cement pump 521.

8, for the sake of convenience of movement and installation of the cement pump 521 and the cement motor 522, the cement room R of the cement room R, in which the cementing unit 500 is disposed in the present embodiment, At least one third rail 550 is provided.

The hoist trolley HT may be supported on the third rail 550 and the hoist trolley HT may be moved back and forth along the third rail 550 to pull the cement pump 521 and the cement motor 522 Can be moved.

Further, the cementing unit 500 further includes a dust collector 560 provided at one side of the cement room R to collect dust contained in the mixed cement, as shown in FIG. 8 do.

Meanwhile, in the present embodiment, the cementing unit 500 is provided in a separate cement room R at a predetermined height from the deck D, as shown in FIG. 2, unlike the other configurations described above. This is to minimize the influence of the external environment when working in the external environment of the cement work and to prevent the delaying of the cementing work.

The triple cabin 600 and the tool house 700 are disposed at the highest position from the deck D, as shown in Fig. 2, and are narrower in space than the other areas. Accordingly, in this embodiment, as shown in FIG. 9, a separate access path 800 is secured in the area where the triple cabin 600 and the tool house 700 are provided, thereby ensuring convenience of movement and safety of the operator There is an advantage to be able to.

As described above, the present embodiment uses the UBD for drilling by lowering the pressure of the drilling fluid by 100-200 psi lower than the pressure of the seabed stratum, so that the solid or drilling fluid does not flow into the bottom layer formed with the well, .

As soon as the drill bit is drilled in the well, the fluid such as crude oil is immediately raised by the pressure difference, so that the fluid stored in the well can be produced early. Furthermore, UBD does not apply pressure in the direction of the seabed so that differential sticking of the drill pipe to the seafloor during drilling is avoided.

In particular, since no pressure is applied in the direction of the seabed layer, the cost of the expensive mud is reduced, the penetration rate is increased, the penetration speed is increased, and the effective removal of the cut material from the drill bit face portion increases the life of the drill bit, Can be significantly reduced.

Furthermore, there is an advantage that a space for separating a well cutting stream supplied from a well during a well test process or a drilling operation or a configuration for cementing can be efficiently arranged, and the space can be utilized to the maximum extent within a limited space.

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: Offshore structure with UBD system
100: Well test separation unit 110: Well test separator
120: Oil separator 130: Steam heat exchanger
140: Surge tank 150: Feed pump
160: First control cabin 200: Nitrogen generating unit
210: nitrogen generator 220: air compressor
230: booster compressor 240: first platform
300: Separation unit 310: First separation unit
320: second separation unit 400: hammer mill unit
410: hopper 420: hammer mill
430: Driving motor 440: Cyclone
450: Oil condenser 460: Steam condenser
470: Separator 480: Oil scrubber
490: Demister 500: Cementing unit
510: Cement mixer 520: Cement unit
530: slurry removing unit 540: surge tank
550: Third rail 560: Dust collector
600: Triple Cabin 700: Tool House
800: Access path C: Crane
D: Deck HT: Hoist trolley
P: Pump R: Cement room
T: Storage tank

Claims (9)

Deck; And
And a UBD system provided in the deck for testing and separating the well-cutting flow of the drilled well using a drilling fluid designed to a pressure lower than the pressure of the seam bed to be drilled,
In the UBD system,
And a hammer mill unit provided on the deck of the stern area of the hull to crush a solid contained in the well cutting stream and separate the separated solid into an isolated product including oil, gas, and the like. The method according to claim 1,
In the UBD system,
And a well test separation unit provided on the deck of the stern area of the hull to separate a well cutting stream supplied in a test process of the well cutting stream. The method according to claim 1,
In the UBD system,
And a nitrogen generating unit provided in said deck of the stern area of the hull to produce nitrogen supplied to said drilling fluid such that said drilling fluid has a pressure lower than the pressure of said seabed strata. The method of claim 3,
Wherein the nitrogen generating unit is installed inside the platform separately provided in the deck and having at least one rail on the ceiling. The method according to claim 1,
In the UBD system,
And a separation unit provided in said deck area between the forward part of the hull and the stern part for separating the separating material including cutting water and drilling fluid from said well cutting flow. delete The method according to claim 1,
In the UBD system,
An offshore structure comprising a triple cabin and a tool house provided in said deck area between the forward and aft portions of the hull and having an approach path. The method according to claim 1,
In the UBD system,
And a cementing unit provided in a sealing chamber of the forefoot region of the hull to supply cement that cement the drilled well. The method according to claim 1,
The offshore structure may include a drill ship, a drilling rig, a jack-up rig or a drilling pant.

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