Trajectory-controllable radial horizontal well drilling process

Abstract

The invention discloses a track-controllable radial horizontal well drilling process, and relates to the field of drilling technologies and oil and gas exploitation. According to the technology, in the horizontal drilling operation process, tools needed for track control mainly comprise a steering tool and an orientation tool, in the horizontal drilling operation process, the two tools are matched and cooperatively work, precise control and adjustment of the well track are achieved, and the drilling task of the radial horizontal well can be efficiently completed. A track-controllable radial horizontal well drilling process mainly comprises the steps of borehole preparation, steering tool sitting hanging and positioning, casing windowing, directional deflecting, horizontal drilling and multi-branch horizontal well drilling, and multi-branch radial horizontal wells with different depths can be achieved through the complete process. Aiming at resources of small marginal oil reservoirs, fault block oil reservoirs, thin oil reservoirs, low-permeability oil reservoirs and the like with different depths, the oil drainage radius is greatly increased, the production capacity of oil and gas wells and the water injection efficiency of water injection wells are improved, and the method is economical, efficient and safe and is an effective means for old well transformation of oil fields, potential tapping of the oil reservoirs and stable production and yield increase.

Description

Technical Field

[0001] The present invention relates to the field of drilling technology and oil and gas exploitation, and in particular to a trajectory-controllable radial horizontal well drilling tool and process. Background Art

[0002] Radial horizontal well technology can penetrate the near-well contamination zone, greatly increase the oil leakage radius, improve the production capacity of oil and gas wells and the injection efficiency of water injection wells, and is economical, efficient and safe. It is an effective means for the transformation of old wells in oil fields, tapping oil reservoirs and stabilizing and increasing production. It is especially suitable for the development of thin oil layers, vertical fractures, heavy oil, low permeability and other reservoirs.

[0003] At present, radial horizontal well side drilling mainly uses tools such as whipstock and diverters to side drill out of the original wellbore at a preset angle. It is impossible to adjust the side drilling direction, angle and other parameters in real time according to the actual situation, and it is also impossible to complete the control of the wellbore trajectory. Summary of the invention

[0004] In view of the defects existing in the prior art, the purpose of the present invention is to achieve the above purpose, and the technical solution adopted by the present invention is:

[0005] A trajectory controllable radial horizontal well drilling process, comprising the steps of:

[0006] 1) Wellbore preparation: well drilling tool assembly - well drilling gauge (5) + weighted drill pipe (4) + screw drill tool (3) + connector (2) + coiled tubing; scraping and milling drilling tool assembly - scraper (8) + screw drill tool (3) + weighted drill pipe (4) + scraper (7) + connector (2) + coiled tubing (1); after determining the target layer for horizontal drilling, first use the coiled tubing to carry the well drilling gauge (5) to conduct well drilling on the shallow casing (6) at the window opening point, and then carry the scraper (7) and scraper (8) to scrape the pipe; the well drilling gauge (5) clears the channel inside the casing to ensure that there are no obstacles; the scraper (7) and scraper (8) perform multiple scraping operations on the inner wall of the casing to remove various pipe wall attachments, laying the foundation for subsequent window opening operations;

[0007] 2) The steering tool (11) is set and positioned: the drilling tool assembly is composed of the steering tool (11) + the conversion joint (10) + the electronic gyroscope (9) + the connector (2) + the coiled tubing (1); the steering tool (11) is lowered to the designed well depth by the coiled tubing (1), the steering tool (11) includes a guide sub (11-1), the electronic gyroscope (9) is used to measure the azimuth and well depth of the guide sub (11-1) to ensure that the steering tool (11) is in the correct position, and then the tool anchor claw (11-7) is pressurized by the internal oil pressure of the steering tool to seal the steering tool (11), and the pipe string above the steering tool (11) is pulled out; the guide sub (11-1) is adjusted to the desired azimuth angle by the steering of the hydraulic motor in the steering tool (11), and then the guide anchor claw (11-8) at the lower end of the guide sub (11-1) is pressurized to fix the guide sub (11-1), and the whole tool is set and positioned;

[0008] 3) Casing (6) window opening: drilling tool assembly - window opening milling cone (13) + screw drill (3) + directional tool (12) + connector (2) + coiled tubing (1); lower the coiled tubing (1) to a certain distance above the guide short section (11-1) of the steering tool (11); slowly probe the top position of the guide short section (11-1), record the length of the coiled tubing (1) at this moment and mark it; continue to slowly lower it, while the directional tool (12) deflects in real time according to the situation, driving the window opening milling cone (13) to perform casing window opening operation at a suitable position. After reaching the designed footage, lift and lower the drilling tool to repeatedly trim the window until the drilling tool is lifted and lowered without obstruction;

[0009] 4) Directional deflection: Drilling tool assembly - deflection drill bit (14) + screw drill (3) + directional tool (12) + connector (2) + coiled tubing (1); the drilling tool assembly is lowered into the coiled tubing (1), and when the deflection drill bit (14) is lowered to the bottom of the well, a mark is made on the surface of the coiled tubing (1); the coiled tubing (1) is lowered to the marked position, and the directional tool (12) adjusts the deflection drill bit (14) to the required deflection angle, and the drilling is completed to the designed well depth, and the eye is reamed several times to ensure that the drill tool is not blocked, and the deflection drilling tool assembly is pulled out;

[0010] 5) Horizontal drilling: drilling tool assembly - PDC drill bit (15) + screw drill bit (3) + directional tool (12) + connector (2) + coiled tubing (1); the drilling tool assembly is lowered into the coiled tubing (1), and drilling begins when the drill bit reaches the bottom of the well. After drilling is normal, the displacement is adjusted to keep the speed of the screw drill bit (3) at an appropriate level, and the hole is reamed several times after drilling a certain length; during horizontal drilling, the built-in gyroscope of the directional tool (12) sends the deflection angle information of the drill bit to the ground in real time, and the wellbore trajectory can be roughly obtained based on the information;

[0011] 6) Multi-branch horizontal well drilling: After completing the drilling of a horizontal wellbore, the drilling tool assembly is pulled out, and a signal is released to relieve the pressure on the anchor claw (11-7) at the deflection guide short section (11-1) of the steering tool and retract it, loosening the deflection guide short section (11-1), and then driving the hydraulic motor to turn the deflection guide short section (11-1) to another direction, and then performing casing window opening, directional deflection and horizontal drilling in this direction to obtain a multi-branch horizontal well; if a multi-branch horizontal well of different depths is required, the steering tool (11) can be unanchored, adjusted to the required depth and re-seated;

[0012] As a further solution, a trajectory controllable radial horizontal well drilling process is characterized in that the tools required for trajectory control during the horizontal drilling operation mainly include a steering tool (11) and a directional tool (12). During the horizontal drilling operation, the two tools cooperate with each other and work in coordination to achieve precise control and adjustment of the wellbore trajectory, and can efficiently complete the radial horizontal well drilling task;

[0013] As a further solution, the steering tool (11) is mainly composed of a guide sub (11-1), a transmission sub (11-2), a valve group sub (11-3), a fuel tank sub (11-4), an anchor sub (11-5) and a battery sub (11-6); a pressure signal preloaded with the working position of the guide sub (11-1) can be released from the wellhead, and the control circuit in the steering tool (11) controls the solenoid valve, thereby completing the control of the hydraulic motor inside the steering tool (11), and adjusting the working position of the guide sub (11-1) so that the drilling tool group is in a specified working position, thereby achieving control of the sidetracking position of the drilling tool;

[0014] As a further solution, the directional tool (12) is mainly composed of a battery and control circuit short section (12-1), an oil tank short section (12-2), a hydraulic drive short section (12-3), and a hydraulic cylinder deflection structure (12-4). In terms of function, it is a directional rotary steering tool, characterized in that an electric drive hydraulic solution is adopted, a closed oil circuit is adopted inside the tool, a drilling trajectory control tool is installed between the drill bit and the remaining functional short sections, and a drilling fluid channel is provided throughout the tool; the hydraulic cylinder deflection structure (12-4) has a built-in gyroscope, which feeds back the deflection angle information of the drill bit to the ground through pressure waves, and then controls the valve group, thereby controlling the extension and retraction of the hydraulic cylinder, and uses the different extension and retraction amounts of the two hydraulic cylinders to give the drill bit a pushing force for deflection, thereby realizing two-dimensional control of the drill bit. As a further solution, a trajectory-controllable radial horizontal well drilling process is characterized in that the tools required for trajectory control during the horizontal drilling operation mainly include a steering tool and a directional tool. During the horizontal drilling operation, the two tools cooperate with each other and work together to achieve precise control and adjustment of the wellbore trajectory, and can efficiently complete the radial horizontal well drilling task; BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0016] Figure 1 It is a schematic diagram of a wellbore preparation and clearing process in a trajectory controllable radial horizontal well drilling process of the present invention;

[0017] Figure 2 It is a schematic diagram of a wellbore preparation scraper pipe in a trajectory controllable radial horizontal well drilling process of the present invention;

[0018] Figure 3 It is a schematic diagram of the sitting and positioning of a steering tool in a trajectory controllable radial horizontal well drilling process of the present invention;

[0019] Figure 4 It is a schematic diagram of casing window opening in a trajectory controllable radial horizontal well drilling process of the present invention;

[0020] Figure 5 It is a schematic diagram of directional deflection in a trajectory-controllable radial horizontal well drilling process of the present invention;

[0021] Figure 6 It is a schematic diagram of horizontal drilling in a trajectory controllable radial horizontal well drilling process of the present invention;

[0022] Figure 7 It is a schematic diagram of multi-branch horizontal well drilling in a trajectory controllable radial horizontal well drilling process of the present invention;

[0023] Figure 8 It is a schematic diagram of the appearance of a directional tool in a trajectory-controllable radial horizontal well drilling process of the present invention;

[0024] Fig. 9 It is a schematic diagram of the appearance of a steering tool in a trajectory-controllable radial horizontal well drilling process of the present invention;

[0025] Fig.10 It is a process flow chart of a trajectory controllable radial horizontal well drilling process of the present invention;

[0026] In the figure: 1. coiled tubing, 2. connector, 3. screw drilling tool, 4. weighted drill pipe, 5. long through-hole gauge, 6. casing, 7. scraper, 8. scraper milling machine, 9. electronic gyroscope, 10. conversion joint, 11. steering tool, 11-1. guide short section, 11-2. transmission short section, 11-3. valve group short section, 11-4. oil tank short section, 11-5. anchoring short section, 11-6. battery short section, 11-7. tool anchor claw, 11-8. guide anchor claw, 12. directional tool, 12-1. battery and control circuit short section, 12-2. oil tank short section, 12-3. hydraulic drive short section, 12-4. hydraulic cylinder deflection structure, 13. window milling cone, 14. deflection drill bit, 15. PDC drill bit. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the embodiments of the present application clearer, the technical solution in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of this application.

[0028] The embodiments of the present invention are further described in detail below with reference to the accompanying drawings.

[0029] A trajectory controllable radial horizontal well drilling process, comprising the steps of:

[0030] 1) Wellbore preparation: Figure 1 and Figure 2 , well-drilling drilling tool combination - well-drilling gauge 5 + weighted drill pipe 4 + screw drill tool 3 + connector 2 + continuous pipe; scraping and milling drilling tool combination - scraper 8 + screw drill tool 3 + weighted drill pipe 4 + scraper 7 + connector 2 + continuous pipe 1; after determining the target layer for horizontal drilling, first use the continuous pipe to carry the well-drilling gauge 5 to dredge the casing 6 shallow at the window opening point, and then carry the scraper 7 and scraper 8 to scrape the pipe; the well-drilling gauge 5 clears the channel inside the casing to ensure that there are no obstacles; the scraper 7 and scraper 8 perform multiple scraping operations on the inner wall of the casing to remove various pipe wall attachments, laying the foundation for subsequent window opening operations;

[0031] 2) Steering tool 11 sitting and positioning: Figure 3, drilling tool assembly - steering tool 11 + conversion joint 10 + electronic gyroscope 9 + connector 2 + coiled tubing 1; the coiled tubing 1 is used to lower the steering tool 11 to the designed well depth. The steering tool 11 contains a guide short section 11-1. The electronic gyroscope 9 is used to measure the azimuth and well depth of the guide short section 11-1 to ensure that the steering tool 11 falls in the correct position, and then the tool anchor claw 11-7 is pressurized by the internal oil pressure of the steering tool to seal the steering tool 11 and pull out the pipe string above the steering tool 11; the guide short section 11-1 is adjusted to the required azimuth angle by the steering of the hydraulic motor in the steering tool 11, and then the guide anchor claw 11-8 at the lower end of the guide short section 11-1 is pressurized to fix the guide short section 11-1, and the entire tool is hung and positioned;

[0032] 3) Casing 6 window: Figure 4 , drilling tool assembly - window milling cone 13 + screw drill 3 + directional tool 12 + connector 2 + coiled tubing 1; lower the coiled tubing 1 to a certain distance above the guide short section 11-1 of the steering tool 11; slowly probe the top position of the guide short section 11-1, record the length of the coiled tubing 1 at this moment and mark it; continue to slowly lower it, and at the same time, the directional tool 12 deflects in real time according to the situation, driving the window milling cone 13 to perform casing window opening operation at a suitable position. After reaching the designed footage, lift and lower the drilling tool to repeatedly trim the window until there is no obstruction when the drilling tool is lowered;

[0033] 4) Directional deflection: Figure 5 , drilling tool assembly - deflection drill bit 14 + screw drill 3 + directional tool 12 + connector 2 + coiled tubing 1; lower the drilling tool assembly from the coiled tubing 1, and when the deflection drill bit 14 reaches the bottom of the well, make a mark on the surface of the coiled tubing 1; lower the coiled tubing 1 to the marked position, and use the directional tool 12 to adjust the deflection drill bit 14 to the required deflection angle, drill to the designed well depth to complete the deflection section, and ream several times to ensure that the drill tool is not blocked, and then pull out the deflection drilling tool assembly;

[0034] 5) Horizontal drilling: Figure 6 , drilling tool assembly - PDC drill bit 15 + screw drill 3 + directional tool 12 + connector 2 + coiled tubing 1; the drilling tool assembly is lowered into the coiled tubing 1, and drilling begins when the drill bit reaches the bottom of the well. After drilling normally, the displacement is adjusted to keep the speed of the screw drill 3 at an appropriate level, and the hole is reamed several times after drilling a certain length; during horizontal drilling, the built-in gyroscope of the directional tool 12 sends the deflection angle information of the drill bit to the ground in real time, and the wellbore trajectory can be roughly obtained based on the information;

[0035] 6) Multi-branch horizontal well drilling: Figure 7After completing the drilling of a horizontal wellbore, the drilling tool assembly is pulled out, and a signal is released to relieve the pressure on the anchor claw 11-7 at the deflection guide short section 11-1 of the steering tool and retract it, loosening the deflection guide short section 11-1, and then driving the hydraulic motor to turn the deflection guide short section 11-1 to another direction, and then performing casing window opening, directional deflection and horizontal drilling in this direction to obtain a multi-branch horizontal well; if a multi-branch horizontal well with different depths is required, the steering tool 11 can be unanchored, adjusted to the required depth and re-seated;

[0036] Furthermore, a trajectory-controllable radial horizontal well drilling process is characterized in that the tools required for trajectory control during the horizontal drilling operation mainly include a steering tool 11 and a directional tool 12. During the horizontal drilling operation, the two tools cooperate with each other and work together to achieve precise control and adjustment of the wellbore trajectory, and can efficiently complete the radial horizontal well drilling task;

[0037] Further, such as Fig. 9 The steering tool 11 is mainly composed of a guide short section 11-1, a transmission short section 11-2, a valve group short section 11-3, a fuel tank short section 11-4, an anchor short section 11-5 and a battery short section 11-6; a pressure signal preloaded with the working position of the guide short section 11-1 can be released from the wellhead, and the control circuit in the steering tool 11 controls the solenoid valve, thereby completing the control of the hydraulic motor inside the steering tool 11, and adjusting the working position of the guide short section 11-1 so that the drilling tool group is in a specified working position, thereby achieving the control of the sidetracking position of the drilling tool;

[0038] Further, such as Figure 8 The directional tool 12 is mainly composed of a battery and control circuit short section 12-1, a fuel tank short section 12-2, a hydraulic drive short section 12-3, and a hydraulic cylinder deflection structure 12-4. It is a directional rotary steering tool in terms of function. It is characterized by the use of an electric drive hydraulic solution, a closed oil circuit inside the tool, and a drilling trajectory control tool installed between the drill bit and the remaining functional short sections, and a drilling fluid channel is provided throughout the tool; the hydraulic cylinder deflection structure 12-4 has a built-in gyroscope, which feeds back the deflection angle information of the drill bit to the ground through a pressure wave, and then controls the valve group, and then controls the extension and retraction of the hydraulic cylinder, and uses the different extension and retraction amounts of the two hydraulic cylinders to give the drill bit a pushing force for deflection, thereby realizing two-dimensional control of the drill bit.

Claims

1. A trajectory controllable radial horizontal well drilling process, comprising the steps of: 1) Wellbore preparation: well drilling tool assembly - well drilling gauge (5) + weighted drill pipe (4) + screw drill tool (3) + connector (2) + coiled tubing; scraping and milling drilling tool assembly - scraper (8) + screw drill tool (3) + weighted drill pipe (4) + scraper (7) + connector (2) + coiled tubing (1); after determining the target layer for horizontal drilling, first use the coiled tubing to carry the well drilling gauge (5) to conduct well drilling on the shallow casing (6) at the window opening point, and then carry the scraper (7) and scraper (8) to scrape the pipe; the well drilling gauge (5) clears the channel inside the casing to ensure that there are no obstacles; the scraper (7) and scraper (8) perform multiple scraping operations on the inner wall of the casing to remove various pipe wall attachments, laying the foundation for subsequent window opening operations; 2) The steering tool (11) is set and positioned: the drilling tool assembly is composed of the steering tool (11) + the conversion joint (10) + the electronic gyroscope (9) + the connector (2) + the coiled tubing (1); the steering tool (11) is lowered to the designed well depth by the coiled tubing (1), the steering tool (11) includes a guide sub (11-1), the electronic gyroscope (9) is used to measure the azimuth and well depth of the guide sub (11-1) to ensure that the steering tool (11) is in the correct position, and then the tool anchor claw (11-7) is pressurized by the internal oil pressure of the steering tool to seal the steering tool (11), and the pipe string above the steering tool (11) is pulled out; the guide sub (11-1) is adjusted to the desired azimuth angle by the steering of the hydraulic motor in the steering tool (11), and then the guide anchor claw (11-8) at the lower end of the guide sub (11-1) is pressurized to fix the guide sub (11-1), and the whole tool is set and positioned; 3) Casing (6) window opening: drilling tool assembly - window opening milling cone (13) + screw drill (3) + directional tool (12) + connector (2) + coiled tubing (1); lower the coiled tubing (1) to a certain distance above the guide short section (11-1) of the steering tool (11); slowly probe the top position of the guide short section (11-1), record the length of the coiled tubing (1) at this moment and mark it; continue to slowly lower it, while the directional tool (12) deflects in real time according to the situation, driving the window opening milling cone (13) to perform casing window opening operation at a suitable position. After reaching the designed footage, lift and lower the drilling tool to repeatedly trim the window until the drilling tool is lifted and lowered without obstruction; 4) Directional deflection: Drilling tool assembly - deflection drill bit (14) + screw drill (3) + directional tool (12) + connector (2) + coiled tubing (1); the drilling tool assembly is lowered into the coiled tubing (1), and when the deflection drill bit (14) is lowered to the bottom of the well, a mark is made on the surface of the coiled tubing (1); the coiled tubing (1) is lowered to the marked position, and the directional tool (12) adjusts the deflection drill bit (14) to the required deflection angle, and the drilling is completed to the designed well depth, and the eye is reamed several times to ensure that the drill tool is not blocked, and the deflection drilling tool assembly is pulled out; 5) Horizontal drilling: drilling tool assembly - PDC drill bit (15) + screw drill bit (3) + directional tool (12) + connector (2) + coiled tubing (1); the drilling tool assembly is lowered into the coiled tubing (1), and drilling begins when the drill bit reaches the bottom of the well. After drilling is normal, the displacement is adjusted to keep the speed of the screw drill bit (3) at an appropriate level, and the hole is reamed several times after drilling a certain length; during horizontal drilling, the built-in gyroscope of the directional tool (12) sends the deflection angle information of the drill bit to the ground in real time, and the wellbore trajectory can be roughly obtained based on the information; 6) Multi-branch horizontal well drilling: After completing the drilling of a horizontal wellbore, the drilling tool assembly is pulled out, and a signal is released to relieve the pressure on the anchor claw (11-7) at the deflection guide short section (11-1) of the steering tool to retract the anchor claw (11-7), loosen the deflection guide short section (11-1), and then drive the hydraulic motor to turn the deflection guide short section (11-1) to another direction, and then perform casing window opening, directional deflection and horizontal drilling in this direction to obtain a multi-branch horizontal well; if a multi-branch horizontal well of different depths is required, the steering tool (11) can be unanchored, adjusted to the required depth and re-seated.

2. According to claim 1, a trajectory controllable radial horizontal well drilling process, characterized in that The tools required for trajectory control during horizontal drilling operations mainly include a steering tool (11) and a directional tool (12). During horizontal drilling operations, these two tools cooperate with each other and work in coordination to achieve precise control and adjustment of the wellbore trajectory, thereby efficiently completing the radial horizontal well drilling task.

3. The steering tool (11) according to claim 2 is mainly composed of a guide sub (11-1), a transmission sub (11-2), a valve group sub (11-3), a tank sub (11-4), an anchor sub (11-5) and a battery sub (11-6); a pressure signal preloaded with the working position of the guide sub (11-1) can be released from the wellhead, and the control circuit in the steering tool (11) controls the solenoid valve, thereby completing the control of the hydraulic motor inside the steering tool (11), and adjusting the working position of the guide sub (11-1) so that the drilling tool group is in a specified working position, thereby achieving control of the side drilling position of the drilling tool.

4. The directional tool (12) according to claim 2 is mainly composed of a battery and control circuit short section (12-1), a fuel tank short section (12-2), a hydraulic drive short section (12-3), and a hydraulic cylinder deflection structure (12-4). It is a directional rotary steering tool in terms of function, characterized in that An electric drive hydraulic solution is adopted, a closed oil circuit is used inside the tool, the drilling trajectory control tool is installed between the drill bit and the other functional short sections, and a drilling fluid channel is provided throughout the tool; the hydraulic cylinder deflection structure (12-4) has a built-in gyroscope, which feeds back the deflection angle information of the drill bit to the ground through pressure waves, and then controls the valve group, thereby controlling the extension and contraction of the hydraulic cylinder, and using the different extension and contraction amounts of the two hydraulic cylinders to give the drill bit a pushing force for deflection, thereby realizing two-dimensional control of the drill bit.

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