Drilling system

Abstract

The invention belongs to the technical field of ocean drilling, and discloses a drilling system which comprises a drilling platform, a drilling assembly, a drill lifting coring assembly, a rope coring assembly and a gas lift reverse circulation coring assembly. A derrick is arranged on the drilling platform; the drilling assembly comprises a top drive and a drill rod set, the top drive is arranged on the derrick, the drill rod set is connected to the output end of the top drive, and the top drive drives the drill rod set to move along the center line of the derrick; the drill lifting coring assembly, the wire line coring assembly and the gas lift reverse circulation coring assembly are all arranged on the drilling platform and selectively connected with the drilling assembly so that the drilling system can be switched among a drill lifting coring mode, a wire line coring mode and a gas lift reverse circulation coring mode. The drilling system has various coring processes, can meet coring operation requirements in various environments such as shallow sea or deep sea, and effectively improves operation efficiency.

Description

Technical Field

[0001] The present invention relates to the field of marine drilling technology, and in particular to a drilling system. Background Art

[0002] Currently, ocean exploration and development are becoming more and more frequent. In order to obtain more information about the seabed strata, more cores need to be taken, especially ocean scientific drilling requires full-hole coring.

[0003] According to the current riser construction technology level, the working water depth cannot exceed 3,000 meters. The original drilling system designed for offshore oil and gas exploration and development will not be able to meet the coring needs in complex environments. Drilling and coring requires frequent removal of the drill rod from the hole, low drilling efficiency, difficulty in re-entering the hole, frequent addition of drill rods, and a series of other problems. At the same time, deep-sea drilling is difficult and the operation time window is narrow. A single drill-lifting and coring method is difficult to meet actual needs.

[0004] Therefore, a drilling system is urgently needed to solve the above-mentioned coring problem. Summary of the invention

[0005] The object of the present invention is to provide a drilling system which has a variety of coring processes, can meet the coring operation requirements in a variety of environments such as shallow sea or deep sea, and effectively improve the operation efficiency.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] Drilling system, including:

[0008] A drilling platform, wherein a derrick is arranged on the drilling platform;

[0009] A drilling assembly, comprising a top drive and a drill rod group, wherein the top drive is arranged on the derrick, the drill rod group is connected to an output end of the top drive, and the top drive drives the drill rod group to move along the center line of the derrick;

[0010] A drill lifting and coring assembly, a rope coring assembly and a gas lift reverse circulation coring assembly, wherein the drill lifting and coring assembly, the rope coring assembly and the gas lift reverse circulation coring assembly are all arranged on the drilling platform and can be selectively connected to the drilling assembly respectively, so that the drilling system can be switched between a drill lifting and coring mode, a rope coring mode and a gas lift reverse circulation coring mode.

[0011] Optionally, the drilling platform includes a coring deck, a drilling deck and a stern pipe deck arranged in sequence along the bow and stern directions of the ship, the derrick is arranged on a drilling floor of the drilling deck, the center line of the derrick is coaxial with the center line of the wellhead on the drilling floor, the coring deck is flush with the drilling floor, and the drilling floor is higher than the stern pipe deck.

[0012] Optionally, two coring rat holes are opened on the side of the wellhead of the drilling platform close to the bow part, and the two coring rat holes are symmetrically distributed along the center line of the wellhead parallel to the bow and stern direction of the ship. The drilling platform is also provided with a bow track, which is arranged on the side of the coring rat holes close to the bow part of the ship and extends along the bow and stern direction of the ship.

[0013] Optionally, the drill lifting and coring assembly includes a coring device conveyor and a conveyor track. The conveyor track is detachably arranged on the drilling platform and connected with the head track. The coring device conveyor is arranged on the conveyor track. When the drilling system is in the drill lifting and coring mode, the coring device conveyor can move along the conveyor track and the head track to transfer the coring device between the coring rat hole and the ship core processing system.

[0014] Optionally, two coring rat holes are opened on one side of the wellhead of the drilling platform close to the bow part, and the two coring rat holes are symmetrically distributed along the wellhead center line parallel to the bow and stern direction of the ship;

[0015] The rope coring assembly includes a coring winch, a rope and a salvage device. The coring winch is arranged on one side of the derrick. A center pulley is arranged on the top of the derrick. The rope is wound around the center pulley. Both ends of the rope are respectively connected to the coring winch and the salvage device. When the drilling system is in the rope coring mode, the coring winch can drive the salvage device to move along the center line of the derrick through the rope, and can also drive the salvage device to move between the wellhead and the coring rat hole through the rope.

[0016] Optionally, the drilling platform is further provided with a bow track, which is arranged on a side of the coring rat hole close to the bow part of the ship and extends along the bow and stern direction of the ship;

[0017] The rope coring assembly also includes a coring machine conveyor and a conveyor track. The conveyor track is detachably arranged on the drilling platform and connected with the head track. The coring machine conveyor is arranged on the conveyor track. The coring machine conveyor can move along the conveyor track and the head track to transfer the coring machine between the coring rat hole and the ship core processing system.

[0018] Optionally, the rope coring assembly further comprises a wire rope blowout preventer, and the wire rope blowout preventer is mounted on the upper end of the main shaft of the top drive.

[0019] Optionally, the gas lift reverse circulation coring assembly includes a core separation device, an air compressor, a dual-channel faucet and a reverse circulation flushing pipe. When the drilling system is in the gas lift reverse circulation coring mode, the core separation device is detachably arranged on the drilling platform and is connected to the top end of the main shaft of the top drive through the reverse circulation flushing pipe. The bottom end of the main shaft of the top drive is connected to the drill pipe group through the dual-channel faucet, and the air compressor is connected to the top end of the dual-channel faucet.

[0020] Optionally, the solid output end of the core separation device is communicated with a ship core processing system, and the liquid output end of the core separation device is communicated with a mud processing system.

[0021] Optionally, a catwalk machine and a catwalk machine track are also provided on the drilling platform. The catwalk machine track is located on a side of the derrick close to the stern and extends in the direction of the bow and stern. The catwalk machine is movably arranged on the catwalk machine track, and the catwalk machine is used to transport drilling tools.

[0022] Beneficial effects of the present invention:

[0023] The drilling system provided by the present invention includes a drilling platform, a drilling assembly, a drill coring assembly, a rope coring assembly and a gas lift reverse circulation coring assembly. Among them, a derrick is arranged on the drilling platform, and the drilling assembly includes a top drive and a drill rod group. The top drive is arranged on the derrick, and the drill rod group is connected to the output end of the top drive. The top drive drives the drill rod group to move along the center line of the derrick, so as to realize the drilling operation at the target position. At the same time, the drill coring assembly, the rope coring assembly and the gas lift reverse circulation coring assembly are all arranged on the drilling platform, and can be selectively connected to the drilling assembly respectively. That is to say, according to actual needs, the drilling assembly can be connected to the drill coring assembly, the rope coring assembly and the gas lift reverse circulation coring assembly respectively, so that the drilling system can switch between the drill coring mode, the rope coring mode and the gas lift reverse circulation coring mode, thereby meeting the operational requirements of drilling and coring in different situations and effectively improving the operational efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments of the present invention. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the contents of the embodiments of the present invention and these drawings without paying any creative work.

[0025] Figure 1 is a schematic structural diagram of a drilling system provided by an embodiment of the present invention;

[0026] Figure 2 is a cross-sectional view of a drilling system provided by an embodiment of the present invention;

[0027] Figure 3 is a top view of a drilling system provided by an embodiment of the present invention;

[0028] Figure 4 It is a schematic diagram of a drilling system provided by an embodiment of the present invention when it is in a gas lift reverse circulation coring mode.

[0029] In the figure:

[0030] 1. Drilling platform; 11. Derrick; 12. Coring deck; 131. Drilling table; 132. Coring rathole; 133. Head track; 134. Tail track; 135. Power rathole; 14. Tail pipe deck; 141. Catwalk; 142. Catwalk track;

[0031] 2. Drilling assembly; 21. Top drive; 22. Drill rod group; 23. Rotary table; 24. Iron roughneck; 25. Driller's room; 26. Hydraulic cathead; 27. Multifunctional manipulator; 28. Stand box;

[0032] 3. Drilling and coring assembly; 31. Coring device conveyor; 32. Conveyor track;

[0033] 4. Rope coring assembly; 41. Coring winch; 42. Rope;

[0034] 5. Air lift reverse circulation coring assembly; 51. Core separation device; 52. Air compressor; 53. Dual-channel faucet; 54. Reverse circulation flushing pipe;

[0035] 61. Cementing manifold; 62. Mud riser manifold. DETAILED DESCRIPTION

[0036] The technical solution of the present invention is further described below with reference to the accompanying drawings and through specific implementation methods.

[0037] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0038] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] It should be noted that similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, further definition and explanation thereof is not required in subsequent drawings.

[0040] In the description of the present invention, it should be noted that the terms "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, or are the positions or positional relationships in which the inventive product is usually placed when in use. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", "third", etc. are only used to distinguish the description, and cannot be understood as indicating or implying relative importance. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0041] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed" and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0042] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0043] In the description of the present invention, the term "and / or" is only a description of the association relationship of associated objects, indicating that there may be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in the present invention generally indicates that the associated objects before and after are in an "or" relationship.

[0044] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0045] This embodiment provides a drilling system, such as Figure 1 and Figure 2 As shown, it includes a drilling platform 1, a drilling assembly 2, a drill lifting and coring assembly 3, a rope coring assembly 4 and a gas lift reverse circulation coring assembly 5.

[0046] Among them, a derrick 11 is arranged on the drilling platform 1, and the drilling assembly 2 includes a top drive 21 and a drill rod group 22. The top drive 21 is arranged on the derrick 11, and the drill rod group 22 is connected to the output end of the top drive 21. The top drive 21 drives the drill rod group 22 to move along the center line of the derrick 11, so as to realize the drilling operation at the target position. At the same time, the drill coring assembly 3, the rope coring assembly 4 and the gas lift reverse circulation coring assembly 5 are all arranged on the drilling platform 1, and can be selectively connected to the drilling assembly 2 respectively. That is to say, according to actual needs, the drilling assembly 2 can be connected to the drill coring assembly 3, the rope coring assembly 4 and the gas lift reverse circulation coring assembly 5 respectively, so that the drilling system can switch between the drill coring mode, the rope coring mode and the gas lift reverse circulation coring mode, thereby meeting the operational requirements of drilling and coring in different situations and effectively improving the operational efficiency.

[0047] Specifically, the drilling platform 1 can be selected as a ship or other offshore operating platform. In this embodiment, the drilling platform 1 is a ship.

[0048] Continue to refer to Figure 1 Along the bow and stern direction of the ship, the drilling platform 1 includes a coring deck 12, a drilling deck and a stern pipe deck 14 which are arranged in sequence. The derrick 11 is arranged on the drilling floor 131 of the drilling deck. The center line of the derrick 11 is coaxial with the center line of the wellhead on the drilling floor 131, which is used to carry out drilling and coring related operations. The coring deck 12 is flush with the drilling floor 131. The coring deck 12 is used to process and assemble coring drill tools and connect with the ship's core processing system. The ship's core processing system can be located at the bow of the coring deck 12 or the lower side of the coring deck 12 to detect and store cores. The drilling floor 131 is higher than the stern pipe deck 14, and the stern pipe deck 14 is used to store tools for laying drill pipes, watertight pipes, etc.

[0049] like Figure 2 and Figure 3As shown, two coring rat holes 132 are opened on the side of the wellhead of the drilling platform 1 close to the bow, and the two coring rat holes 132 are symmetrically distributed along the center line of the wellhead parallel to the bow and stern direction of the ship. The coring rat holes 132 can be used to store the coring device, so as to serve as a temporary storage tool during the period when the coring device is taken out from the wellhead until it is transferred to the ship core processing system. Specifically, the coring rat holes 132 are arranged at a position as close to the wellhead as possible and within the operation coverage of the pipe laying machine. The pipe laying machine can put the coring device taken out from the wellhead into the coring rat hole 132 for temporary storage, and can also send the coring device in the coring rat hole 132 to the wellhead position. A bow track 133 is also provided on the drilling platform 1, and the bow track 133 is arranged on the side of the coring rat hole 132 close to the bow of the ship, and extends along the bow and stern direction of the ship.

[0050] Optionally, the drill lifting and coring assembly 3 includes a coring device conveyor 31 and a conveyor track 32. The conveyor track 32 is detachably arranged on the drilling platform 1 and connected with the head track 133, and the coring device conveyor 31 is arranged on the conveyor track 32. When the drilling system is in the drill lifting and coring mode, the conveyor track 32 is installed on the coring deck 12, and the coring device conveyor 31 can move along the conveyor track 32 and the head track 133 to transfer the coring device between the coring rat hole 132 and the ship core processing system. The coring device conveyor 31 can put the transported empty coring barrel into the coring rat hole 132 for temporary storage, and can also send the coring device storing the core in the coring rat hole 132 into the coring device conveyor 31 for transportation.

[0051] Optionally, the rope coring assembly 4 includes a coring winch 41, a rope 42 and a salvage. The coring winch 41 is arranged on one side of the derrick 11, a central pulley is arranged on the top of the derrick 11, and a rope 42 is wound around the central pulley, and the two ends of the rope 42 are respectively connected to the coring winch 41 and the salvage. The salvage has a locking mechanism and can salvage the coring device in the well. When the drilling system is in the rope coring mode, the coring winch 41 can drive the salvage device to move along the center line of the derrick 11 through the rope 42, and can also drive the salvage device to move between the wellhead and the coring rat hole 132 through the rope 42. At the same time, a conveyor track 32 is installed on the coring deck 12, and the coring device conveyor 31 is arranged on the conveyor track 32. The coring device conveyor 31 can move along the conveyor track 32 and the head track 133 to transfer the coring device between the coring rat hole 132 and the ship core processing system.

[0052] Furthermore, the rope coring assembly 4 further comprises a wire rope blowout preventer, which is mounted on the upper end of the main shaft of the top drive 21. During the process of the coring winch 41 driving the rope 42 to lift up, if gas backflow occurs, the wire rope blowout preventer can be closed to seal the wire rope to prevent gas from overflowing the derrick 11.

[0053] More optionally, if Figure 1and Figure 4 As shown, the gas lift reverse circulation coring assembly 5 includes a core separation device 51, an air compressor 52, a dual-channel faucet 53 and a reverse circulation flushing pipe 54. The air compressor 52 is arranged on the rear pipe deck 14, and the core separation device 51 is detachably arranged on the drilling platform 1. When the drilling system is in the gas lift reverse circulation coring mode, the core separation device 51 is installed on the coring deck 12, and the core separation device 51 is connected to the top of the main shaft of the top drive 21 through the reverse circulation flushing pipe 54. The bottom end of the main shaft of the top drive 21 is connected to the drill pipe group 22 through the dual-channel faucet 53, and the air compressor 52 is connected to the top of the dual-channel faucet 53. The core separation device 51 is used to separate the solid and liquid of the fluid returned in the well.

[0054] Specifically, the solid output end of the core separation device 51 is connected to the core processing system of the ship, and the liquid output end of the core separation device 51 is connected to the mud processing system. In other words, the liquid output end of the core separation device 51 is connected to the mud processing pipeline pre-buried in the hull. After the core separation device 51 separates the core and the seawater, the core is collected on the coring deck 12, and the seawater is discharged to the mud processing system through the pre-buried mud processing pipeline.

[0055] Optionally, continue to refer to Figure 1-Figure 3 The drilling platform 1 also includes a moon pool, a main deck and a moon pool elevation platform. The moon pool is located directly below the drilling platform 131 and is used to connect the drilling platform 131 and the seabed. The main deck is flush with the rear pipe deck 14. Left and right elevation platforms are set in the moon pool, and the drilling platform 131 is higher than the rear pipe deck 14. The drilling platform 131 is also provided with a turntable 23, an iron roughneck 24, a power mouse hole 135, a driller's room 25 (control system), a hydraulic cathead 26, a cementing manifold 61, a mud riser manifold 62, a multifunctional manipulator 27 and a root box 28. The derrick 11 is also equipped with a lifting system, a finger beam, a pipe laying machine and a salvage manipulator. The top drive 21 is installed with different accessories according to different coring modes. When the drill coring mode and the rope coring mode are used, a wire rope blowout preventer is installed on the upper part of the hollow main shaft of the top drive 21. When the gas lift reverse circulation coring mode is used, the hollow main shaft of the top drive 21 is directly connected to the mud pipeline, and the mud pipe hose is connected to the core separation device 51 through the mud pipe hard pipe.

[0056] Optionally, the drilling platform 1 is also provided with a catwalk machine 141 and a catwalk machine track 142. Specifically, a tail track 134 is also provided on the drilling platform 131, and the tail track 134 is provided on the side of the coring rat hole 132 close to the stern of the ship, and extends along the bow and stern direction of the ship. A catwalk machine platform is provided on the rear pipe deck 14, and the catwalk machine platform is flush with the drilling platform 131. The catwalk machine 141 and the catwalk machine track 142 are arranged on the catwalk machine platform. The catwalk machine track 142 is connected with the tail track 134, and the catwalk machine 141 moves along the catwalk machine track 142 and the tail track 134 to transport the drilling tools on the rear pipe deck 14 in and out of the drilling platform 131.

[0057] The two coring rat holes 132 in this embodiment are respectively recorded as No. 1 coring rat hole 132 and No. 2 coring rat hole 132. The operation steps of the drilling system provided in this embodiment when in the drill lifting coring mode, the rope coring mode and the gas lift reverse circulation coring mode are as follows:

[0058] 1. When the drilling system is in the drilling and coring mode:

[0059] During the operation, the coring device to be used in the next step is placed in advance in the No. 1 coring rat hole 132, and a drill rod is drilled into the well using the drilling equipment so that the coring device in the well is filled with cores. Subsequently, the drill rod is brought out and placed in the root box 28, and the coring device filled with cores is placed in the No. 2 coring rat hole 132, and the coring device pre-stored in the No. 1 coring rat hole 132 is immediately taken out, and the drill rod stored in the root box 28 is connected to start the next round of coring work. Finally, the coring device with cores stored in the No. 1 coring rat hole 132 is transported to the ship's core processing system through the corer conveyor 31 on the drilling table 131, and a new coring device is placed in the No. 1 coring rat hole 132. Repeat the above steps to carry out the work of lifting the drill and coring.

[0060] 2. When the drilling system is in rope coring mode:

[0061] During the operation, the corer to be used in the next step is placed in advance in the No. 1 coring rat hole 132, and a drill rod is drilled using drilling equipment to fill the corer in the well with cores. Subsequently, the coring winch 41 is started, and the salvage at the terminal of the coring winch 41 is lowered to the bottom of the borehole through the wire rope blowout preventer and the top drive 21, so that the salvage is connected to the corer. Next, the coring winch 41 is started to recover the corer filled with cores. During the process of the coring winch 41 driving the rope 42 to lift up, if gas returns, the wire rope blowout preventer can be closed to close the wire rope to prevent gas from overflowing the derrick 11. The corer filled with cores is placed in the No. 2 coring rat hole 132, and the salvage at the terminal of the coring winch 41 is immediately used to connect the corer pre-stored in the No. 1 coring rat hole 132, and it is dropped into the wellbore through the upper top drive 21 to start the next round of coring work. Finally, the corer with the core stored in the No. 1 coring rat hole 132 is transported to the ship core processing system through the corer conveyor 31 on the drilling floor 131, and a new corer is placed in the No. 1 coring rat hole 132. Repeat the above steps to carry out the rope 42 coring work.

[0062] 3. When the drilling system is in gas lift reverse circulation coring mode:

[0063] During operation, the high-pressure air compressor 52 is started and begins to deliver high-pressure gas. The gas enters the drill pipe annulus through the double-channel faucet 53 at the bottom of the top drive 21 and mixes with the liquid in the drill pipe. Then the core in the drill pipe is returned through the top drive 21 and the reverse circulation flushing pipe 54, and enters the core separation device 51 through the slag discharge pipeline. The core separation device 51 separates the core and collects it.

[0064] Obviously, the above embodiments of the present invention are only examples for clearly explaining the present invention, and are not intended to limit the implementation methods of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A drilling system, characterized in that: include: A drilling platform (1), wherein a derrick (11) is arranged on the drilling platform (1); A drilling assembly (2), comprising a top drive (21) and a drill rod group (22), wherein the top drive (21) is arranged on the derrick (11), the drill rod group (22) is connected to the output end of the top drive (21), and the top drive (21) drives the drill rod group (22) to move along the center line of the derrick (11); A drill-lift coring assembly (3), a rope coring assembly (4) and a gas-lift reverse circulation coring assembly (5), wherein the drill-lift coring assembly (3), the rope coring assembly (4) and the gas-lift reverse circulation coring assembly (5) are all arranged on the drilling platform (1) and can be selectively connected to the drilling assembly (2) respectively, so that the drilling system can be switched between a drill-lift coring mode, a rope (42) coring mode and a gas-lift reverse circulation coring mode.

2. The drilling system according to claim 1, characterized in that: The drilling platform (1) comprises a coring deck (12), a drilling deck and a stern pipe deck (14) which are arranged in sequence along the bow and stern directions of the ship; the derrick (11) is arranged on a drilling floor (131) of the drilling deck; the center line of the derrick (11) is coaxial with the center line of a wellhead on the drilling floor (131); the coring deck (12) is flush with the drilling floor (131); and the drilling floor (131) is higher than the stern pipe deck (14).

3. The drilling system according to claim 1, characterized in that: Two coring rat holes (132) are provided on a side of the wellhead of the drilling platform (1) close to the bow part, and the two coring rat holes (132) are symmetrically distributed along a wellhead center line parallel to the bow and stern direction of the ship. A bow track (133) is also provided on the drilling platform (1), and the bow track (133) is provided on a side of the coring rat holes (132) close to the bow part of the ship and extends along the bow and stern direction of the ship.

4. The drilling system according to claim 3, characterized in that: The drill lifting and coring assembly (3) comprises a coring device conveyor (31) and a conveyor track (32). The conveyor track (32) is detachably arranged on the drilling platform (1) and connected with the head track (133). The coring device conveyor (31) is arranged on the conveyor track (32). When the drilling system is in the drill lifting and coring mode, the coring device conveyor (31) can move along the conveyor track (32) and the head track (133) to transfer the coring device between the coring rat hole (132) and the ship core processing system.

5. The drilling system according to claim 1, characterized in that: Two coring rat holes (132) are provided on one side of the wellhead of the drilling platform (1) close to the bow portion, and the two coring rat holes (132) are symmetrically distributed along a wellhead center line parallel to the bow and stern direction of the ship; The rope coring assembly (4) comprises a coring winch (41), a rope (42) and a salvage device. The coring winch (41) is arranged on one side of the derrick (11). A central pulley is arranged on the top of the derrick (11). The rope (42) is wound around the central pulley. The two ends of the rope (42) are respectively connected to the coring winch (41) and the salvage device. When the drilling system is in the rope (42) coring mode, the coring winch (41) can drive the salvage device to move along the center line of the derrick (11) through the rope (42), and can also drive the salvage device to move between the wellhead and the coring rat hole (132) through the rope (42).

6. The drilling system according to claim 5, characterized in that: The drilling platform (1) is also provided with a bow track (133), which is arranged on a side of the coring rat hole (132) close to the bow part and extends along the bow and stern direction of the ship; The rope coring assembly (4) also includes a coring machine conveyor (31) and a conveyor track (32). The conveyor track (32) is detachably arranged on the drilling platform (1) and connected to the head track (133). The coring machine conveyor (31) is arranged on the conveyor track (32). The coring machine conveyor (31) can move along the conveyor track (32) and the head track (133) to transfer the coring machine between the coring rat hole (132) and the ship core processing system.

7. The drilling system according to claim 6, characterized in that: The rope coring assembly (4) further comprises a wire rope blowout preventer, which is mounted on the upper end of the main shaft of the top drive (21).

8. The drilling system according to claim 1, characterized in that: The gas lift reverse circulation coring assembly (5) comprises a core separation device (51), an air compressor (52), a dual-channel faucet (53) and a reverse circulation flushing pipe (54). When the drilling system is in the gas lift reverse circulation coring mode, the core separation device (51) is detachably arranged on the drilling platform (1) and is connected to the top end of the main shaft of the top drive (21) through the reverse circulation flushing pipe (54). The bottom end of the main shaft of the top drive (21) is connected to the drill pipe group (22) through the dual-channel faucet (53), and the air compressor (52) is connected to the top end of the dual-channel faucet (53).

9. The drilling system according to claim 8, characterized in that: The solid output end of the core separation device (51) is in communication with the ship core processing system, and the liquid output end of the core separation device (51) is in communication with the mud processing system.

10. The drilling system according to any one of claims 1 to 9, characterized in that: The drilling platform (1) is also provided with a catwalk machine (141) and a catwalk machine track (142); the catwalk machine track (142) is located on a side of the derrick (11) close to the stern and extends in the direction of the bow and stern; the catwalk machine (141) is movably arranged on the catwalk machine track (142); and the catwalk machine (141) is used to transport drilling tools.

Images