Natural gas hydrate generation simulation cabin coring system convenient for mechanical parameter acquisition

Abstract

The invention discloses a natural gas hydrate generation simulation cabin coring system facilitating mechanical parameter collection, and belongs to the technical field of coring experiment equipment. Comprising a feeding system which is connected with a drilling system, a drilling rod is arranged at the output end of the drilling system, the drilling system drives the drilling rod to rotate, the feeding system controls the drilling rod to ascend and descend, and drilling coring simulation of a natural gas hydrate in-situ reservoir in a reaction kettle is achieved; the mechanical acquisition system comprises a tension and pressure sensor, a torque sensor and a three-way force sensor, the tension and pressure sensor and the torque sensor are mounted between the output end of the drilling system and the drill rod, the three-way force sensor is fixed at the bottom of the reaction kettle, and a test end of the three-way force sensor extends into the reaction kettle. According to the method, the multi-dimensional mechanical parameters in the hydrate reservoir coring drilling process can be obtained, and powerful data support is provided for natural gas hydrate fidelity coring technology research.

Description

Technical Field

[0001] The present invention relates to the technical field of coring experimental equipment, in particular to a natural gas hydrate formation simulation cabin coring system which is convenient for collecting mechanical parameters. Background Art

[0002] Research methods for natural gas hydrate drilling and coring can be categorized into three categories: field experiments, numerical simulations, and laboratory simulations. Currently, field experiments are costly and expensive, and are limited by existing coring equipment and technology. The resulting natural gas hydrate samples can be irreversibly distorted due to temperature, pressure, and other factors. Numerical simulations are time-consuming and the reliability of their results depends on the rationality of the model and the authenticity of the parameters, thus providing only a limited basis for field experiments. Laboratory simulations, however, offer low cost, high controllability, and realistic results, making them a suitable method for studying natural gas hydrate fidelity coring.

[0003] Currently, most of the equipment used in existing laboratories to study natural gas hydrates can only collect conventional temperature and pressure data, but its ability to collect mechanical data is limited. In particular, mechanical data during the drilling and coring process is difficult to collect, and therefore cannot provide sufficient data support for the research on natural gas hydrate fidelity coring technology.

[0004] To this end, the present invention proposes a natural gas hydrate formation simulation chamber coring system that is convenient for collecting mechanical parameters. Summary of the Invention

[0005] The purpose of the present invention is to provide a natural gas hydrate formation simulation chamber coring system that is convenient for collecting mechanical parameters, aiming to solve the technical problem of insufficient collection of mechanical parameters during the coring process.

[0006] To achieve the above-mentioned object, the present invention provides the following solution: The present invention provides a natural gas hydrate formation simulation chamber coring system that facilitates the acquisition of mechanical parameters, comprising:

[0007] A feeding system, wherein the feeding system is connected to the drilling system, a drill rod is provided at the output end of the drilling system, the drilling system drives the drill rod to rotate, and the feeding system controls the lifting movement of the drill rod to realize the drilling and coring simulation of the natural gas hydrate in-situ reservoir in the reactor by the drill rod;

[0008] A mechanical acquisition system includes a tension and pressure sensor, a torque sensor, and a three-axis force sensor. The tension and pressure sensor and the torque sensor are installed in series between the output end of the drilling system and the drill pipe. The three-axis force sensor is fixed to the bottom of the reactor, and its test end extends into the interior of the reactor.

[0009] Preferably, a core hole penetrating the bottom is opened in the middle of the drill rod, and a plug is detachably connected to the bottom of the core hole.

[0010] Preferably, the bottom of the outer side wall of the drill rod is provided with an external thread, and the external thread can be threadedly connected to a coring drill bit of different configurations.

[0011] Preferably, a borehole is provided on the reactor cover, a dynamic sealing device is provided in the borehole, and the drill rod is sealedly connected to the borehole through the dynamic sealing device.

[0012] Preferably, a mounting hole coaxial with the drilled hole is provided on the inner bottom wall of the kettle cover, and the inner diameter of the mounting hole is larger than the inner diameter of the drilled hole; the dynamic sealing device includes a rotary sealing retaining ring, a rotary sealing ring and a rotary sealing pressure cap which are sequentially arranged in the mounting hole, the rotary sealing retaining ring is attached to the inner top wall of the mounting hole, and the rotary sealing ring is located between the rotary sealing retaining ring and the rotary sealing pressure cap.

[0013] Preferably, the rotary sealing retaining ring, the rotary sealing ring and the rotary sealing pressure cap are all rotatably connected to the mounting hole via bearings.

[0014] Preferably, the drilling system includes a bracket fixed to the output end of the feed system, a servo motor is installed on the bracket, the output shaft of the servo motor is connected to the motor coupling, the tension and pressure sensor is arranged between one end of the motor coupling and the bracket, the other end of the motor coupling is connected to the torque sensor, and the other end of the torque sensor is connected to the top of the drill rod.

[0015] Preferably, multiple sets of monitoring components are arranged in layers along the height direction of the side wall of the reactor, and the monitoring components include multiple temperature and pressure sensors. The test ends of the temperature and pressure sensors extend into the interior of the reactor, and the multiple temperature and pressure sensors in each layer are evenly distributed along the circumference of the side wall of the reactor.

[0016] The present invention discloses the following technical effects:

[0017] 1. Multi-dimensional mechanical parameter acquisition capability: Through the coordinated work of tension and pressure sensors, torque sensors, and three-axis force sensors, key mechanical parameters such as axial force, torque, and three-axis force during the drilling and coring process can be comprehensively acquired.

[0018] 2. Strong controllability of process parameters: Process parameters such as drill pipe rotation speed, feed rate and bit pressure can be precisely controlled, and the influence of different drilling processes on hydrate reservoirs can be systematically studied.

[0019] 3. Excellent sealing performance: The innovative dynamic sealing device design ensures that the reactor maintains a high-pressure and low-temperature environment during the movement of the drill pipe, simulating the real submarine hydrate reservoir conditions.

[0020] 4. Strong adaptability: Coring drill bits of different configurations can be replaced to adapt to different formation characteristics and drilling requirements.

[0021] 5. Comprehensive data support: It provides reliable experimental data support for the research on natural gas hydrate fidelity coring technology, filling the gap in existing technology in mechanical parameter collection. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The accompanying drawings, which constitute part of this application, are intended to provide a further understanding of this application. The exemplary embodiments and descriptions of this application are intended to explain this application and do not constitute an improper limitation on this application. In the accompanying drawings:

[0023] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0024] Figure 2 It is a structural schematic diagram of the drilling system of the present invention;

[0025] Figure 3 Schematic diagram of the structure of the dynamic sealing device of the present invention;

[0026] Figure 4 Schematic diagram of the distribution of temperature and pressure sensors in the present invention.

[0027] Explanation of the marks in the figure: 1. Motor coupling; 2. Servo motor; 3. One-way thrust ball bearing; 4. Drill pipe coupling; 5. Deep groove ball bearing; 6. Bracket; 7. Torque sensor; 8. Latch; 9. Drill pipe; 10. Plug; 11. Tension and pressure sensor; 12. Dynamic sealing device; 13. Reactor; 14. Reactor cover; 15. Rotary sealing retaining ring; 16. Rotary sealing ring; 17. Rotary sealing pressure cap; 18. Temperature and pressure sensor; 19. Three-axis force sensor. DETAILED DESCRIPTION

[0028] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0030] Reference Figures 1-4 The present invention provides a natural gas hydrate formation simulation chamber coring system that facilitates the acquisition of mechanical parameters, comprising:

[0031] Feeding system: The feeding system is connected to the drilling system, and a drill rod 9 is provided at the output end of the drilling system. The drilling system drives the drill rod 9 to rotate, and the feeding system controls the raising and lowering movement of the drill rod 9 to simulate the drilling and coring of the natural gas hydrate in situ reservoir in the reactor 13 by the drill rod 9.

[0032] Mechanical acquisition system: This includes a tension and pressure sensor 11, a torque sensor 7, and a three-axis force sensor 19. The tension and pressure sensor 11 and the torque sensor 7 are installed in series between the drilling system output and the drill pipe 9. The three-axis force sensor 19 is fixed to the bottom of the reactor 13, with its test end extending into the reactor 13.

[0033] The feed system and drilling system coordinately drive the drill pipe 9 into the reactor 13, achieving precise simulation of the in-situ coring process for natural gas hydrate reservoirs. During drilling, the tension and pressure sensor 11, torque sensor 7, and triaxial force sensor 19 respectively collect key mechanical data, including the axial force and torque acting on the drill pipe, and the triaxial forces acting on the sediment layer. By controlling the operating parameters of the feed system and drilling system, the effects of different drilling process parameters on hydrate reservoir damage can be systematically studied. Comprehensive mechanical parameters during hydrate reservoir coring can be obtained, providing reliable experimental data support for research on fidelity coring technology for natural gas hydrates.

[0034] In a preferred embodiment, the feeding system may be in the form of a hydraulic cylinder, an air cylinder, a linear motor or a screw-nut mechanism, etc., to achieve precise lifting and lowering control of the drill rod 9.

[0035] In the preferred embodiment, a core hole is defined in the middle of the drill rod 9, extending through the bottom. A plug 10 is removably connected to the bottom of the core hole. This plug 10 is connected to the core hole via a threaded or clipped connection. Removing the plug 10 during drilling simulates coring. During the coring process, the tension and pressure sensor 11 and torque sensor 7 collect real-time data on the axial force and torque acting on the drill rod.

[0036] In a preferred embodiment, the outer bottom wall of the drill pipe 9 is provided with external threads, which can be threaded into coring drill bits of various configurations. The front end of the drill pipe is prefabricated with M27 male threads, allowing for replacement of coring drill bits of various configurations based on the physical and mechanical properties of the hydrate simulated formation, achieving optimal coring performance to accommodate different drilling requirements and formation characteristics.

[0037] In a preferred embodiment, a borehole is provided on the reactor cover 14 of the reactor 13 , a dynamic sealing device 12 is provided in the borehole, and the drill rod 9 is sealedly connected to the borehole via the dynamic sealing device 12 .

[0038] In a preferred embodiment, a mounting hole coaxial with the drilled hole is defined in the inner bottom wall of the kettle cover 14, and the inner diameter of the mounting hole is larger than the inner diameter of the drilled hole. The dynamic seal 12 includes a rotary seal retainer 15, a rotary seal ring 16, and a rotary seal pressure cap 17, which are sequentially disposed within the mounting hole. The rotary seal retainer 15 is attached to the inner top wall of the mounting hole, and the rotary seal ring 16 is located between the rotary seal retainer 15 and the rotary seal pressure cap 17.

[0039] The rotary seal retainer 15, rotary seal ring 16, and rotary seal pressure cap 17 are all annular structures, with the drill pipe extending through their inner bores. When the drill pipe 9 enters the rotary seal ring 16, pressure is generated, squeezing the drill pipe 9 circumferentially against the inner wall of the reactor cover to achieve a seal. The rotary seal retainer 15 and rotary seal pressure cap 17 act as a fixed stop at both ends to prevent excessive deformation of the rotary seal ring 16 and stabilize it. This device ensures that the reactor maintains a pressure seal while simultaneously enabling coring during drill pipe drilling, maintaining a high-pressure, low-temperature environment within the hydrate reservoir.

[0040] In a preferred embodiment, the rotary seal retainer ring 15, the rotary seal ring 16, and the rotary seal pressure cap 17 are all rotatably connected to the mounting holes via bearings. When the drill rod 9 rotates, the seals rotate accordingly, reducing relative motion with the drill rod, reducing wear, and extending service life.

[0041] In a preferred embodiment, the drilling system includes a bracket 6 fixed to the output end of the feed system, a servo motor 2 is installed on the bracket 6, the output shaft of the servo motor 2 is connected to the motor coupling 1, a tension and pressure sensor 11 is arranged between one end of the motor coupling 1 and the bracket 6, and the other end is connected to the torque sensor 7, and the other end of the torque sensor 7 is connected to the top of the drill rod 9.

[0042] A drill pipe coupling 4 is provided between the torque sensor 7 and the drill pipe 9. The torque sensor 7 is threadedly connected to the top of the drill pipe coupling 4. The bottom of the drill pipe coupling 4 is threadedly connected to the top of the drill pipe 9 and further locked by a latch 8. The drill pipe coupling 4 is rotationally connected to the bracket 6 via a one-way thrust ball bearing 3 and a deep groove ball bearing 5.

[0043] In a preferred embodiment, multiple monitoring assemblies are layered along the height of the reactor 13's sidewalls. These monitoring assemblies include multiple temperature and pressure sensors 18. The test ends of the temperature and pressure sensors 18 extend into the reactor 13, and the multiple temperature and pressure sensors 18 in each layer are evenly distributed along the circumference of the reactor 13's sidewalls.

[0044] During hydrate formation, five distributed temperature and pressure sensors 18 monitor temperature and pressure changes within the reactor 13 in real time, inferring hydrate formation activity. During hydrate coring experiments, real-time temperature and pressure changes around the hydrate borehole are collected to investigate the impact of the coring process on hydrate decomposition. A torque sensor 7 monitors drilling torque within the drill pipe 9, a tension-pressure sensor 11 measures axial force within the drill pipe, and a triaxial force sensor 19 monitors triaxial forces acting on the entire sediment layer. These multiple sensors work together to provide real-time monitoring of multiple key thermal and mechanical parameters.

[0045] Workflow: After the hydrate is generated in the reactor 13, the drilling and coring simulation begins. The servo motor 2 drives the drill rod 9 into the reactor 13 for drilling. The drill rod rotation speed (0-200r / min), feed speed (0-0.1m / min), and drilling pressure can be adjusted. The maximum drilling depth is 570mm to study the destructive effects of different drilling parameters on the hydrate reservoir. The front end of the drill rod 9 is equipped with a special coring drill bit. The coring action simulation can be realized by removing the plug 10. During the drilling and coring process, the tension and pressure sensor 11 and the torque sensor 7 collect the axial force and torque of the drill rod in real time. The front end of the drill rod 9 is prefabricated with an M27 male thread. Coring drill bits of different configurations can be replaced according to the physical and mechanical properties of the hydrate simulated formation to achieve optimal coring performance to adapt to different drilling requirements and formation characteristics.

[0046] In the description of the present invention, it should be understood that the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention.

[0047] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Without departing from the design concept of the present invention, various modifications and improvements made by ordinary technicians in this field to the technical solution of the present invention should fall within the scope of protection determined by the claims of the present invention.

Claims

1. A natural gas hydrate formation simulation chamber coring system that facilitates the acquisition of mechanical parameters, characterized in that: include: A feeding system, wherein the feeding system is connected to a drilling system, a drill rod (9) is provided at an output end of the drilling system, the drilling system drives the drill rod (9) to rotate, and the feeding system controls the lifting movement of the drill rod (9) to realize a simulation of drilling and coring of a natural gas hydrate in-situ reservoir in a reactor (13) by the drill rod (9); A mechanical acquisition system, comprising a tension and pressure sensor (11), a torque sensor (7) and a three-axis force sensor (19), wherein the tension and pressure sensor (11) and the torque sensor (7) are installed in series between the output end of the drilling system and the drill rod (9), and the three-axis force sensor (19) is fixed to the bottom of the reactor (13), with its test end extending into the interior of the reactor (13).

2. The natural gas hydrate formation simulation chamber coring system for facilitating mechanical parameter collection according to claim 1, characterized in that: A core hole penetrating the bottom is provided in the middle of the drill rod (9), and a detachable connecting plug (10) is provided at the bottom of the core hole.

3. The natural gas hydrate formation simulation chamber coring system for facilitating mechanical parameter collection according to claim 1 is characterized in that: The bottom of the outer side wall of the drill rod (9) is provided with an external thread, and the external thread can be threadedly connected to a coring drill bit of different configurations.

4. The natural gas hydrate formation simulation chamber coring system for facilitating mechanical parameter collection according to claim 1, characterized in that: A borehole is provided on the reactor cover (14) of the reactor (13), a dynamic sealing device (12) is provided in the borehole, and the drill rod (9) is sealedly connected to the borehole via the dynamic sealing device (12).

5. The natural gas hydrate formation simulation chamber coring system for facilitating mechanical parameter collection according to claim 4 is characterized in that: The inner bottom wall of the kettle cover (14) is provided with a mounting hole coaxial with the drilled hole, and the inner diameter of the mounting hole is larger than the inner diameter of the drilled hole; the dynamic sealing device (12) comprises a rotary sealing retaining ring (15), a rotary sealing ring (16) and a rotary sealing pressure cap (17) which are sequentially arranged in the mounting hole, the rotary sealing retaining ring (15) is attached to the inner top wall of the mounting hole, and the rotary sealing ring (16) is located between the rotary sealing retaining ring (15) and the rotary sealing pressure cap (17).

6. The natural gas hydrate formation simulation chamber coring system for facilitating mechanical parameter collection according to claim 5, characterized in that: The rotary sealing retaining ring (15), the rotary sealing ring (16) and the rotary sealing pressing cap (17) are all rotatably connected to the mounting hole via bearings.

7. The natural gas hydrate formation simulation chamber coring system for facilitating mechanical parameter collection according to claim 1, characterized in that: The drilling system comprises a bracket (6) fixed to the output end of the feed system, a servo motor (2) is mounted on the bracket (6), an output shaft of the servo motor (2) is connected to a motor coupling (1), a tension and pressure sensor (11) is arranged between one end of the motor coupling (1) and the bracket (6), the other end of the motor coupling (1) is connected to the torque sensor (7), and the other end of the torque sensor (7) is connected to the top of the drill rod (9).

8. The natural gas hydrate formation simulation chamber coring system for facilitating mechanical parameter collection according to claim 1, characterized in that: The side wall of the reactor (13) is provided with multiple sets of monitoring components in layers along the height direction. The monitoring components include multiple temperature and pressure sensors (18). The test ends of the temperature and pressure sensors (18) extend into the interior of the reactor (13). The multiple temperature and pressure sensors (18) in each layer are evenly distributed along the circumference of the side wall of the reactor (13).

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