A composite rotary steering drilling biasing device with auxiliary pushing-out function

Abstract

The application discloses a composite rotary steering drilling biasing device with an auxiliary pushing-out function, which comprises a drill bit shaft, a rear drill bit shaft, a hollow universal joint and a drill string shaft which are sequentially connected in series through screwing to form a rotating assembly, a center of the rotating assembly forms a main flow channel of drilling fluid, an inner sleeve shell is coaxially sleeved, a secondary flow channel of drilling fluid is formed between the inner sleeve shell and the outer sleeve shell, an outer pushing mechanism and an inner pushing mechanism are sequentially arranged in the secondary flow channel of drilling fluid, the outer pushing mechanism extends out of the outer sleeve shell, an auxiliary pushing-out mechanism is arranged on the outer pushing mechanism, the outer pushing mechanism is matched with the well wall through the auxiliary pushing-out mechanism, the inner pushing mechanism extends into the inner sleeve shell, and the inner pushing mechanism is matched with the rear drill bit shaft through pushing; and the inner sleeve shell, the outer sleeve shell, the auxiliary pushing-out mechanism, the outer pushing mechanism and the inner pushing mechanism jointly form a non-rotating assembly. The application can meet the need of building an inclination under various complex working conditions, adopts the working mode of pushing the well wall outward and pushing the main shaft inward, greatly improves the inclination building capacity, reduces the dependence on the well wall, and further improves the wellbore quality.

Description

Technical Field

[0001] This invention belongs to the field of rotary steerable drilling technology, and in particular relates to a composite rotary steerable drilling offset device with an auxiliary ejection function. Background Technology

[0002] Rotary Steerable System (RSS) is developed from the traditional sliding steerable drilling system. It mainly uses a bottom steerable actuator to change the azimuth and inclination of the drill string while rotating, thereby achieving automatic guidance.

[0003] Rotary steerable drilling systems employ measurement-while-drilling (MSW) technology. A microprocessor installed downhole can collect real-time data on the bottom hole conditions and transmit it to the surface via drilling fluid, forming a two-way closed-loop control with the surface and the bottom hole, thereby achieving automatic guidance.

[0004] Because rotary steerable drilling tools drill by rotating, compared with traditional sliding steerable drilling tools, they overcome the disadvantage of high frictional resistance during drilling, reduce the number of drilling trips, and produce a smoother wellbore, which can effectively improve the efficiency and economic benefits of oil and gas well development.

[0005] Currently, conventional rotary steerable drilling tools can be classified into static offset push rotary steerable drilling tools, dynamic offset push rotary steerable drilling tools, static offset pointing rotary steerable drilling tools, and dynamic offset pointing rotary steerable drilling tools.

[0006] Conventional static offset push-type rotary steerable drilling tools rely on telescopic ribs near the drill bit to push against the well wall, thereby causing the drill bit to deflect and change the drilling direction. They are characterized by precise wellbore trajectory and low frictional resistance. However, they also have disadvantages such as very complex structure, low hydraulic control precision, poor extension capability, and the potential to result in spiral wellbores.

[0007] Conventional dynamic offset push-type rotary steerable drilling tools rely on an offset actuator to generate an offset force, which directly or indirectly bends the mandrel, thereby causing the drill bit to offset and change the drilling direction. They feature precise wellbore trajectory, low frictional resistance, smooth wellbore, and good cleaning effect. However, they also have disadvantages such as impact and vibration caused by the guide push plate, severe tool wear, sealing difficulties, the possibility of spiral wellbore formation, tool lateral force dependence on drill bit pressure drop, and significant dependence on the wellbore.

[0008] Conventional static offset directional rotary steerable drilling tools do not rotate with the drill string during drilling. When guidance is needed, the offset actuator provides guiding force in a fixed direction. They feature low frictional resistance, high efficiency, facilitate the elimination of wellbore helical deformation, low vibration, and good wellbore cleaning. However, their control spindle is subjected to high-load alternating stress, making it prone to fatigue fracture and significantly impacting tool life.

[0009] Conventional dynamic offset directional rotary steerable drilling tools have a steerable actuator that rotates with the drill string during drilling. When guidance is needed, the control system directs the offset actuator to provide directional force at a specific position. These tools feature low frictional resistance, high efficiency, the ability to eliminate borehole helicalization, independence from drill bit pressure drop, high stability, and high reliability. However, the ball bearings in these tools experience significant wear, which substantially impacts their lifespan. Summary of the Invention

[0010] To address the problems existing in the prior art, this invention provides a composite rotary steerable drilling offset device with an auxiliary ejection function, which can meet the needs of directional drilling under various complex working conditions. It adopts an external pushing well wall and internal pushing spindle working mode, which greatly improves the directional drilling capacity, effectively reduces the dependence on the well wall, and further improves the wellbore quality. The auxiliary ejection mechanism is installed on a non-rotating sleeve housing, which prevents the auxiliary ejection mechanism from rotating with the spindle, reduces the wear of the auxiliary ejection mechanism, and improves the service life of the auxiliary ejection mechanism. The auxiliary ejection mechanism adopts a purely mechanical structure, which only uses the upward drilling fluid as a power source and does not require external power supply, making it more adaptable.

[0011] To achieve the above objectives, the present invention adopts the following technical solution: a composite rotary steerable drilling offset device with an auxiliary ejection function, comprising a front drill bit shaft, a rear drill bit shaft, a hollow universal joint, a drill string shaft, an inner sleeve housing, an outer sleeve housing, and an auxiliary ejection mechanism; the front drill bit shaft, the rear drill bit shaft, the hollow universal joint, and the drill string shaft are sequentially connected in series to form a rotating assembly, and the center of the rotating assembly forms the main channel for drilling fluid; the lower end of the front drill bit shaft is provided with an enlarged diameter section, and the upper end of the drill string shaft is provided with an enlarged diameter section; the inner sleeve housing is coaxially fitted on the outside of the rotating assembly, and the inner sleeve housing is located between the enlarged diameter sections of the front drill bit shaft and the drill string shaft; a thrust bearing is provided between the upper end of the inner sleeve housing and the drill string shaft, and a deep groove ball bearing assembly is provided between the inner sleeve housing below the thrust bearing and the drill string shaft; the inner sleeve... The contact surface between the lower end face of the outer casing and the stepped surface of the expanded section of the front drill bit shaft is set as a spherical surface; the outer casing is coaxially fixedly fitted onto the outside of the inner casing, forming a drilling fluid secondary flow channel between the outer casing and the inner casing. The lower end of the drilling fluid secondary flow channel is connected to the main drilling fluid flow channel, and the upper end of the drilling fluid secondary flow channel is connected to the external space of the outer casing; an outward pushing mechanism and an inward pushing mechanism are sequentially arranged in the drilling fluid secondary flow channel; the outward pushing mechanism extends outward from the outer casing, and the auxiliary pushing mechanism is set on the outward pushing mechanism, which cooperates with the well wall through the auxiliary pushing mechanism; the inward pushing mechanism extends inward from the inner casing, and cooperates with the rear drill bit shaft through the push; the inner casing, outer casing, auxiliary pushing mechanism, outward pushing mechanism, and inward pushing mechanism together form a non-rotating assembly.

[0012] There are four drilling fluid auxiliary channels, which are evenly distributed along the circumference. Each drilling fluid auxiliary channel is equipped with an external push mechanism and an internal push mechanism. Each external push mechanism is equipped with an auxiliary push mechanism. The outer sleeve shell adopts a four-petal combined splicing structure. Each single petal of the outer sleeve shell is provided with a drilling fluid auxiliary channel between it and the inner sleeve shell.

[0013] The main drilling fluid channel and the secondary drilling fluid channel are connected by a drilling fluid inlet hole, and the secondary drilling fluid channel is connected to the external space of the outer casing by a drilling fluid outlet hole.

[0014] A valve block is provided at the drilling fluid inlet. A power chamber is located between the inner and outer sleeve shells below the valve block. The power chamber houses the valve block actuator and a power battery. The valve block actuator includes a servo motor, a coupling, a ball screw, a nut slider, and a bearing seat. The servo motor is fixedly mounted in the power chamber. The motor shaft of the servo motor is coaxially connected to one end of the ball screw via the coupling. The nut slider is fitted onto the other end of the ball screw. The valve block and the nut slider are fixedly connected together. The ball screw is connected to the power chamber via a bearing seat. The servo motor is powered by a power battery.

[0015] The push mechanism includes a piston chamber and a push piston. The piston chamber is built into the outer sleeve shell, and the push piston is located in the piston chamber. The rodless chamber of the piston chamber is connected to the drilling fluid auxiliary flow channel, and the rod chamber of the piston chamber is connected to the external space of the outer sleeve shell. The piston rod of the push piston extends to the external space of the outer sleeve shell, and the auxiliary push mechanism is installed at the end of the piston rod of the push piston.

[0016] The internal pushing mechanism includes an active wedge, a driven wedge, and a buffer spring; an active wedge limiting groove is built into the outer sleeve shell, the active wedge is located in the active wedge limiting groove, and the buffer spring is disposed between the active wedge and the active wedge limiting groove; a driven wedge through hole is opened on the inner sleeve shell, and the driven wedge is inserted into the driven wedge through hole; the driven wedge is perpendicular to the active wedge, the outer end inclined surface of the driven wedge is in abutting contact with the lower end inclined surface of the active wedge, and a buffer pad is fixedly fitted on the rear drill bit shaft directly opposite the inner end of the driven wedge, and the inner end of the driven wedge is in abutting contact with the rear drill bit shaft through the buffer pad.

[0017] The auxiliary ejection mechanism includes a supporting bottom cover, an outer push-out top cover, a drive gear, a first intermediate gear, a second intermediate gear, a first driven gear, a second driven gear, a first stud, a second stud, a one-way valve, a first electromagnetic inlet valve, and a second electromagnetic inlet valve. The supporting bottom cover and the outer push-out top cover are fastened together. The drive gear is located at the center of the inner side of the supporting bottom cover, and a speed sensor is configured at the shaft end of the drive gear. The first intermediate gear and the second intermediate gear are mirror-symmetrically distributed on both sides of the drive gear, and the first intermediate gear and the second intermediate gear mesh with the drive gear simultaneously. The first stud is located directly above the first intermediate gear, and the first driven gear is coaxially fixed to the lower part of the first stud, meshing with the first intermediate gear. The second stud is located directly above the second intermediate gear, and the second driven gear is coaxially fixed to the lower part of the second stud, meshing with the second intermediate gear. The drive gear, the first intermediate gear, the second intermediate gear, the first stud, the second stud ... The stud and the second stud have only rotational freedom relative to the support bottom cover; a first upward drilling fluid inlet hole is provided on the support bottom cover below the first intermediate gear, and the first electromagnetic inlet valve is installed at the first upward drilling fluid inlet hole; a second upward drilling fluid inlet hole is provided on the support bottom cover below the second intermediate gear, and the second electromagnetic inlet valve is installed at the second upward drilling fluid inlet hole; a flow guide platform is provided between the first electromagnetic inlet valve and the second electromagnetic inlet valve, and the flow guide surface of the flow guide platform is tangentially distributed with the drive gear; an upward drilling fluid outlet hole is provided on the support bottom cover directly above the drive gear, and the one-way valve is installed at the upward drilling fluid outlet hole; a first threaded sleeve stud and a second threaded sleeve stud are fixedly provided inside the outer push top cover; the first stud and the first threaded sleeve stud are screwed together, and the second stud and the second threaded sleeve stud are screwed together; filter screens are provided at the outer openings of the first upward drilling fluid inlet hole, the second upward drilling fluid inlet hole, and the drilling fluid outlet hole.

[0018] Lifting guide blind holes are provided at the four corners of the inner side of the supporting bottom cover, and lifting guide columns are provided at the four corners of the inner side of the outer push top cover. The lifting guide columns are inserted and guided by the lifting guide blind holes.

[0019] Both the first intermediate gear and the second intermediate gear have extended shaft structures. A first guide cylinder and a second guide cylinder are fixed inside the outer push-top cover. The extended section of the gear shaft of the first intermediate gear is inserted into and guided by the first guide cylinder. The extended section of the gear shaft of the second intermediate gear is inserted into and guided by the second guide cylinder.

[0020] The bottom center of the support cover is provided with a transition boss, and the top of the piston rod of the outward-pushing piston is provided with a transition groove. The support cover is fixedly connected to the transition groove at the top of the piston rod of the outward-pushing piston through the transition boss.

[0021] The beneficial effects of this invention are:

[0022] The composite rotary steerable drilling offset device with auxiliary pushing function of the present invention combines the features of directional and push-type rotary steerable drilling tools, and can realize the cooperation of "pushing outward well wall" and "pushing inward spindle", which greatly improves the tool's directional drilling capability.

[0023] The composite rotary steerable drilling offset device of the present invention with an auxiliary ejection function can meet the directional drilling task by activating the auxiliary ejection mechanism when the internal and external drilling hydraulic pressure difference is insufficient, thus compensating for the disadvantage of poor directional drilling capability when the drilling hydraulic pressure difference is insufficient.

[0024] The composite rotary steerable drilling offset device of the present invention, which has an auxiliary pushing function, reduces the dependence on the well wall through the cooperation of "pushing the well wall" and "pushing the spindle", and the wellbore quality is also smoother.

[0025] The composite rotary steerable drilling offset device of the present invention, with an auxiliary push-out function, has a certain directional drilling capability when facing formations with relatively smooth well walls, such as salt layers, through the working mode of "inward push spindle", without relying on the well wall.

[0026] The composite rotary steerable drilling offset device with auxiliary ejection function of the present invention has an auxiliary ejection mechanism that is a purely mechanical structure that uses only the upward drilling fluid as a power source and does not require external power supply, thus having a stronger adaptability.

[0027] The present invention relates to a composite rotary steerable drilling offset device with an auxiliary ejection function, wherein the auxiliary ejection mechanism is mounted on a non-rotating sleeve housing, thereby preventing the auxiliary ejection mechanism from rotating with the main shaft, reducing wear on the auxiliary ejection mechanism, and improving the service life of the auxiliary ejection mechanism.

[0028] The composite rotary steerable drilling offset device with auxiliary ejection function of the present invention adopts a gear reduction transmission structure for its auxiliary ejection mechanism, which makes the transmission smoother and stronger, and ensures the reliability of the directional drilling task. Attached Figure Description

[0029] Figure 1 This is a schematic diagram (sectional view) of the overall structure of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention;

[0030] Figure 2 This is a three-dimensional schematic diagram of the overall structure of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention.

[0031] Figure 3 This is a schematic diagram of the rotating component structure of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention;

[0032] Figure 4 This is a schematic diagram of the inner sleeve shell structure of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention;

[0033] Figure 5 This is a schematic diagram of the single-lobed structure of the outer casing of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention;

[0034] Figure 6 This is a schematic diagram of the valve block actuator structure of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention;

[0035] Figure 7 This is a schematic diagram of the internal thrust mechanism of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention.

[0036] Figure 8 This is a schematic diagram of the pusher piston structure of the composite rotary steerable drilling offset device with auxiliary push-out function of the present invention;

[0037] Figure 9 This is a schematic diagram of the auxiliary ejection mechanism of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention;

[0038] Figure 10 This is a schematic diagram of the auxiliary ejection mechanism of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention (view 1, external push-out top cover not shown);

[0039] Figure 11 This is a schematic diagram of the auxiliary ejection mechanism of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention (view 2, external push-out top cover not shown);

[0040] Figure 12 This is a schematic diagram of the auxiliary ejection mechanism of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention (view 3, external push-out top cover not shown);

[0041] Figure 13 This is a schematic diagram of the support bottom cover structure of the composite rotary steerable drilling offset device with auxiliary ejection function of the present invention;

[0042] Figure 14 This is a schematic diagram of the external push-top cover structure of the composite rotary steerable drilling offset device with auxiliary push-out function of the present invention;

[0043] In the diagram, 1—front drill bit shaft, 2—rear drill bit shaft, 3—hollow universal joint, 4—drill string shaft, 5—inner sleeve housing, 6—outer sleeve housing, 7—auxiliary ejection mechanism, 8—drilling fluid main channel, 9—thrust bearing, 10—deep groove ball bearing assembly, 11—drilling fluid secondary channel, 12—outer thrust mechanism, 13—inner thrust mechanism, 14—drilling fluid inlet, 15—drilling fluid outlet, 16—valve block, 17—power chamber, 18—valve block actuator, 19—power battery, 20—servo motor, 21—coupling, 22—ball screw, 23—nut slider, 24—bearing seat, 25—piston chamber, 26—outer thrust piston, 27—active wedge, 28—driven wedge, 29—buffer spring, 30—active wedge limit groove. 31—Driven wedge through hole; 32—Buffer pad; 33—Support bottom cover; 34—Outward push top cover; 35—Drive gear; 36—First intermediate gear; 37—Second intermediate gear; 38—First driven gear; 39—Second driven gear; 40—First stud; 41—Second stud; 42—One-way valve; 43—First electromagnetic inlet valve; 44—Second electromagnetic inlet valve; 45—First upward drilling fluid inlet hole; 46—Second upward drilling fluid inlet hole; 47—Upward drilling fluid outlet hole; 48—First threaded sleeve column; 49—Second threaded sleeve column; 50—Lifting guide blind hole; 51—Lifting guide column; 52—First guide column; 53—Second guide column; 54—Transition boss; 55—Transition groove; 56—Drainage platform. Detailed Implementation

[0044] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0045] like Figures 1-14As shown, a composite rotary steerable drilling offset device with an auxiliary ejection function includes a front drill bit shaft 1, a rear drill bit shaft 2, a hollow universal joint 3, a drill string shaft 4, an inner sleeve housing 5, an outer sleeve housing 6, and an auxiliary ejection mechanism 7. The front drill bit shaft 1, the rear drill bit shaft 2, the hollow universal joint 3, and the drill string shaft 4 are sequentially connected in series to form a rotating assembly, and a drilling fluid main channel 8 is formed at the center of the rotating assembly. The lower end of the front drill bit shaft 1 is provided with an enlarged diameter section, and the upper end of the drill string shaft 4 is provided with an enlarged diameter section. The inner sleeve housing 5 is coaxially fitted on the outside of the rotating assembly, and the inner sleeve housing 5 is located between the enlarged diameter sections of the front drill bit shaft 1 and the drill string shaft 4. A thrust bearing 9 is provided between the upper end of the inner sleeve housing 5 and the drill string shaft 4, and a deep groove ball bearing assembly 10 is provided between the inner sleeve housing 5 and the drill string shaft 4 below the thrust bearing 9. The lower end face of the inner sleeve housing 5 is connected to the enlarged diameter section of the front drill bit shaft 1. The contact surface between the trapezoidal surfaces is set as a spherical surface; the outer sleeve shell 6 is coaxially fixedly fitted on the outside of the inner sleeve shell 5, forming a drilling fluid secondary flow channel 11 between the outer sleeve shell 6 and the inner sleeve shell 5. The lower end of the drilling fluid secondary flow channel 11 is connected to the main drilling fluid flow channel 8, and the upper end of the drilling fluid secondary flow channel 11 is connected to the external space of the outer sleeve shell 6; an outward pushing mechanism 12 and an inward pushing mechanism 13 are sequentially arranged in the drilling fluid secondary flow channel 11; the outward pushing mechanism 12 extends outward from the outer sleeve shell 6, and the auxiliary pushing mechanism 7 is arranged on the outward pushing mechanism 12, which cooperates with the well wall through the auxiliary pushing mechanism 7; the inward pushing mechanism 13 extends inward from the inner sleeve shell 5, and cooperates with the rear drill bit shaft 2; the inner sleeve shell 5, the outer sleeve shell 6, the auxiliary pushing mechanism 7, the outward pushing mechanism 12, and the inward pushing mechanism 13 together form a non-rotating assembly.

[0046] There are four drilling fluid auxiliary channels 11, which are evenly distributed along the circumference. Each drilling fluid auxiliary channel 11 is equipped with an outward pushing mechanism 12 and an inward pushing mechanism 13. Each outward pushing mechanism 12 is equipped with an auxiliary pushing mechanism 7. The outer sleeve shell 6 adopts a four-petal combined splicing structure. Each single petal of the outer sleeve shell 6 is provided with a drilling fluid auxiliary channel 11 between it and the inner sleeve shell 5.

[0047] The main drilling fluid channel 8 and the secondary drilling fluid channel 11 are connected by the drilling fluid inlet hole 14, and the secondary drilling fluid channel 11 is connected to the external space of the outer casing 6 by the drilling fluid outlet hole 15.

[0048] A valve block 16 is provided at the drilling fluid inlet 14. A power chamber 17 is provided between the inner sleeve housing 5 and the outer sleeve housing 6 below the valve block 16. A valve block actuator 18 and a power battery 19 are provided in the power chamber 17. The valve block actuator 18 includes a servo motor 20, a coupling 21, a ball screw 22, a nut slider 23, and a bearing seat 24. The servo motor 20 is fixedly embedded in the power chamber 17. The motor shaft of the servo motor 20 is coaxially fixed to one end of the ball screw 22 through the coupling 21. The nut slider 23 is fitted onto the other end of the ball screw 22. The valve block 16 is fixedly connected to the nut slider 23. The ball screw 22 is connected to the power chamber 17 through the bearing seat 24. The servo motor 20 is powered by the power battery 19.

[0049] The push mechanism 12 includes a piston chamber 25 and a push piston 26. The piston chamber 25 is built into the outer sleeve housing 6. The push piston 26 is located in the piston chamber 25. The rodless chamber of the piston chamber 25 is connected to the drilling fluid auxiliary flow channel 11, and the rod chamber of the piston chamber 25 is connected to the external space of the outer sleeve housing 6. The piston rod of the push piston 26 extends to the external space of the outer sleeve housing 6, and the auxiliary push mechanism 7 is installed at the end of the piston rod of the push piston 26.

[0050] The inner pushing mechanism 13 includes an active wedge 27, a driven wedge 28, and a buffer spring 29. An active wedge limiting groove 30 is built into the outer sleeve housing 6, the active wedge 27 is located in the active wedge limiting groove 30, and the buffer spring 29 is disposed between the active wedge 27 and the active wedge limiting groove 30. A driven wedge through hole 31 is opened on the inner sleeve housing 5, and the driven wedge 28 is inserted into the driven wedge through hole 31. The driven wedge 28 is perpendicular to the active wedge 27, the outer end inclined surface of the driven wedge 28 abuts against the lower end inclined surface of the active wedge 27, and a buffer pad 32 is fixedly fitted on the rear drill shaft 2 directly opposite the inner end of the driven wedge 28. The inner end of the driven wedge 28 abuts against the rear drill shaft 2 through the buffer pad 32.

[0051] The auxiliary ejection mechanism 7 includes a supporting bottom cover 33, an outer push top cover 34, a drive gear 35, a first intermediate gear 36, a second intermediate gear 37, a first driven gear 38, a second driven gear 39, a first stud 40, a second stud 41, a one-way valve 42, a first electromagnetic inlet valve 43, and a second electromagnetic inlet valve 44; the supporting bottom cover 33 and the outer push top cover 34 are fastened together; the drive gear 35 is located at the center of the inner side of the supporting bottom cover 33, and a speed sensor is arranged at the shaft end of the drive gear 35; the first intermediate gear 36 and the second intermediate gear 37 are mirror-symmetrically distributed. On both sides of the driving gear 35, the first intermediate gear 36 and the second intermediate gear 37 simultaneously mesh with the driving gear 35; the first stud 40 is located directly above the first intermediate gear 36, and the first driven gear 38 is coaxially fixed to the lower part of the first stud 40, meshing with the first intermediate gear 36; the second stud 41 is located directly above the second intermediate gear 37, and the second driven gear 39 is coaxially fixed to the lower part of the second stud 41, meshing with the second intermediate gear 37; the driving gear 35, the first intermediate gear 36, and the second intermediate gear... 37. The first stud 40 and the second stud 41 have only rotational freedom relative to the support base cover 33; a first upward drilling fluid inlet hole 45 is provided on the support base cover 33 below the first intermediate gear 36, and the first electromagnetic inlet valve 43 is installed at the first upward drilling fluid inlet hole 45; a second upward drilling fluid inlet hole 46 is provided on the support base cover 33 below the second intermediate gear 37, and the second electromagnetic inlet valve 44 is installed at the second upward drilling fluid inlet hole 46; a diversion platform 56 is provided between the first electromagnetic inlet valve 43 and the second electromagnetic inlet valve 44. The drainage surface of 56 is tangentially distributed with the drive gear 35; an upward drilling fluid discharge hole 47 is provided on the support bottom cover 33 directly above the drive gear 35, and the one-way valve 42 is installed at the upward drilling fluid discharge hole 47; a first threaded sleeve column 48 and a second threaded sleeve column 49 are fixedly provided inside the outer push top cover 34; the first threaded column 40 is screwed into the first threaded sleeve column 48, and the second threaded column 41 is screwed into the second threaded sleeve column 49; a filter screen is provided at the outer opening of the first upward drilling fluid inlet hole 45, the second upward drilling fluid inlet hole 46, and the drilling fluid discharge hole 47.

[0052] Lifting guide blind holes 50 are provided at the four corners of the inner side of the support bottom cover 33, and lifting guide columns 51 are provided at the four corners of the inner side of the outer push top cover 34. The lifting guide columns 51 are inserted into the lifting guide blind holes 50 for guidance.

[0053] The gear shafts of the first intermediate gear 36 and the second intermediate gear 37 are both extended shaft structures. A first guide cylinder 52 and a second guide cylinder 53 are fixed inside the outer push-top cover 34. The extended section of the gear shaft of the first intermediate gear 36 is inserted into the first guide cylinder 52 for guiding engagement. The extended section of the gear shaft of the second intermediate gear 37 is inserted into the second guide cylinder 53 for guiding engagement.

[0054] The support bottom cover 33 has a transition boss 54 at the center of its bottom and a transition groove 55 at the top of the piston rod of the outward-pushing piston 26. The support bottom cover 33 is fixedly connected to the transition groove 55 at the top of the piston rod of the outward-pushing piston 26 through the transition boss 54.

[0055] The following describes a single use of the present invention with reference to the accompanying drawings:

[0056] When directional drilling is required, the servo motor 20 inside the valve block actuator 18 is first activated. The servo motor 20 drives the ball screw 22 to rotate in the forward direction, causing the nut slider 23 and the valve block 16 to move upward synchronously. The valve block 16 releases the blockage of the drilling fluid inlet hole 14. The high-pressure downward drilling fluid flowing in the main drilling fluid channel 8 will enter the secondary drilling fluid channel 11 through the unsealed drilling fluid inlet hole 14. After passing through the external push mechanism 12 and the internal push mechanism 13 in sequence, it finally flows into the external space of the outer sleeve shell 6 from the drilling fluid outlet hole 15 and mixes with the upward drilling fluid.

[0057] When the high-pressure downhole drilling fluid passes through the push mechanism 12, it directly acts on the push piston 26 through the rodless chamber of the piston chamber 25, driving the piston rod of the push piston 26 to push outward, and finally driving the auxiliary push mechanism 7 to push outward as a whole. The push top cover 34 of the auxiliary push mechanism 7 directly contacts the well wall, realizing the "pushing outward well wall" directional drilling task.

[0058] Meanwhile, when the high-pressure down-draft drilling fluid passes through the internal thrust mechanism 13, it will directly push the active wedge 27 to slide down in the active wedge limiting groove 30, and the impact force during the sliding process will be reduced by the buffer spring 29. As the active wedge 27 moves, the axial movement of the active wedge 27 will be synchronously converted into the radial movement of the driven wedge 28. The driven wedge 28 directly abuts against the rear drill bit shaft 2 through the buffer pad 32, causing the front drill bit shaft 1 and the rear drill bit shaft 2 to deflect around the hollow universal joint 3 as a whole, thus realizing the directional drilling task of the "internal thrust spindle".

[0059] If the directional drilling rate still does not meet the requirements after the outward pushing mechanism 12 and the inward pushing mechanism 13, the auxiliary pushing mechanism 7 is further activated to control the opening of the first electromagnetic inlet valve 43. The upward drilling fluid in the outer space of the outer casing 6 flows into the support bottom cover 33 through the first upward drilling fluid inlet hole 45. Under the guidance of the diversion platform 56, the upward drilling fluid will first drive the drive gear 35 to rotate clockwise, and then directly return to the outer space of the outer casing 6 through the drilling fluid discharge hole 47 via the one-way valve 42. As the drive gear 35 rotates clockwise, it will synchronously drive the first intermediate... Gear 36 and the second intermediate gear 37 rotate counterclockwise, which in turn drives the first driven gear 38 and the second driven gear 39 to rotate clockwise synchronously. This ultimately drives the first stud 40 and the second stud 41 to rotate clockwise synchronously. The rotational motion of the first stud 40 and the second stud 41 is synchronously converted into the linear outward movement of the first guide cylinder 52 and the second guide cylinder 53, which ultimately drives the push-out top cover 34 to push out independently, further increasing the push-out distance of the "push-out well wall" and thus further increasing the build-up rate. When the build-up rate reaches the required level, the second electromagnetic inlet valve 44 is closed.

[0060] After the directional drilling task is completed, the valve block actuator 18 controls the valve block 16 to reset, and the valve block 16 re-seals the drilling fluid discharge hole 14, cutting off the inflow of high-pressure downward drilling fluid. The drilling fluid secondary flow channel 11 is only connected to the external space of the outer casing 6 through the drilling fluid discharge hole 15. The drilling fluid secondary flow channel 11 achieves pressure balance with the external space of the outer casing 6. At this time, the external push mechanism 12 and the internal push mechanism 13 also reset under pressure balance after losing the pressure difference effect.

[0061] Simultaneously, the second electromagnetic inlet valve 44 opens, and the upward drilling fluid in the outer space of the outer sleeve shell 6 flows into the support bottom cover 33 through the second upward drilling fluid inlet hole 46. Under the guidance of the diversion platform 56, the upward drilling fluid will first drive the drive gear 35 to rotate counterclockwise, and then directly return to the outer space of the outer sleeve shell 6 through the drilling fluid discharge hole 47 via the one-way valve 42. As the drive gear 35 rotates counterclockwise, it will synchronously drive the first intermediate gear 36 and the second intermediate gear 37 to rotate clockwise, and then drive the first driven gear 38 and the second driven gear 39 to rotate counterclockwise synchronously. Finally, it will drive the first stud 40 and the second stud 41 to rotate counterclockwise synchronously. The rotational motion of the first stud 40 and the second stud 41 will be synchronously converted into the linear downward motion of the first guide cylinder 52 and the second guide cylinder 53, and finally drive the outer push top cover 34 to fall back and reset. At this time, the second electromagnetic inlet valve 44 returns to the closed state.

[0062] In this embodiment, the distance by which the push-out top cover 34 is pushed outward independently is set to 5mm to 8mm, which is controlled by the number of rotations of the first stud 40 and the second stud 41. The number of rotations of the first stud 40 and the second stud 41 is indirectly measured by the speed sensor equipped on the shaft end of the drive gear 35. The external threads of the first stud 40 and the second stud 41 adopt 0.3750-24UNJF-3A external threads with an outer diameter of 9.525mm, a pitch of 1.06mm, and a thread accuracy grade of 3A, which can ensure that the external threads of the first stud 40 and the second stud 41 have a relatively thick thickness, thereby ensuring that the external threads have good strength when working.

[0063] The solutions described in the embodiments are not intended to limit the scope of patent protection of this invention. All equivalent implementations or modifications that do not depart from the scope of this invention are included in the patent scope of this case.

Claims

1. A composite rotary steerable drilling offset device with auxiliary ejection function, characterized in that: The assembly includes a front drill bit spindle, a rear drill bit spindle, a hollow universal joint, a drill string spindle, an inner sleeve housing, an outer sleeve housing, and an auxiliary ejection mechanism. The front drill bit spindle, rear drill bit spindle, hollow universal joint, and drill string spindle are sequentially connected in series to form a rotating assembly, with the center of the rotating assembly forming the main drilling fluid channel. The lower end of the front drill bit spindle has an enlarged diameter section, and the upper end of the drill string spindle also has an enlarged diameter section. The inner sleeve housing is coaxially fitted onto the outside of the rotating assembly, located between the enlarged diameter sections of the front drill bit spindle and the drill string spindle. A thrust bearing is provided between the upper end of the inner sleeve housing and the drill string spindle, and a deep groove ball bearing assembly is provided between the inner sleeve housing below the thrust bearing and the drill string spindle. The contact surface between the lower end face of the inner sleeve housing and the stepped surface of the enlarged diameter section of the front drill bit spindle is designed with... The outer sleeve shell is spherical; it is coaxially fixedly fitted onto the outside of the inner sleeve shell, forming a drilling fluid secondary flow channel between the outer sleeve shell and the inner sleeve shell. The lower end of the drilling fluid secondary flow channel is connected to the main drilling fluid flow channel, and the upper end of the drilling fluid secondary flow channel is connected to the external space of the outer sleeve shell. An outward pushing mechanism and an inward pushing mechanism are sequentially arranged in the drilling fluid secondary flow channel. The outward pushing mechanism extends outward from the outer sleeve shell, and an auxiliary pushing mechanism is set on the outward pushing mechanism. The outward pushing mechanism cooperates with the well wall through the auxiliary pushing mechanism. The inward pushing mechanism extends inward from the inner sleeve shell and cooperates with the rear drill bit shaft. The inner sleeve shell, outer sleeve shell, auxiliary pushing mechanism, outward pushing mechanism, and inward pushing mechanism together form a non-rotating assembly. The auxiliary ejection mechanism includes a supporting bottom cover, an outer push-out top cover, a drive gear, a first intermediate gear, a second intermediate gear, a first driven gear, a second driven gear, a first stud, a second stud, a one-way valve, a first electromagnetic inlet valve, and a second electromagnetic inlet valve. The supporting bottom cover and the outer push-out top cover are fastened together. The drive gear is located at the center of the inner side of the supporting bottom cover, and a speed sensor is configured at the shaft end of the drive gear. The first intermediate gear and the second intermediate gear are mirror-symmetrically distributed on both sides of the drive gear, and the first intermediate gear and the second intermediate gear mesh with the drive gear simultaneously. The first stud is located directly above the first intermediate gear, and the first driven gear is coaxially fixed to the lower part of the first stud, and the first driven gear meshes with the first intermediate gear. The second stud is located directly above the second intermediate gear, and the second driven gear is coaxially fixed to the lower part of the second stud, meshing with the second intermediate gear. The driving gear, the first intermediate gear, the second intermediate gear, the first stud, and the second stud have only rotational freedom relative to the support base cover. A first upward drilling fluid inlet hole is provided on the support base cover below the first intermediate gear, and the first electromagnetic inlet valve is installed at the first upward drilling fluid inlet hole. A second upward drilling fluid inlet hole is provided on the support base cover below the second intermediate gear, and the second electromagnetic inlet valve is installed at the second upward drilling fluid inlet hole. At the well fluid inlet; a flow guide platform is provided between the first and second electromagnetic inlet valves, with the flow guide surface of the platform tangentially distributed to the drive gear; an upward drilling fluid discharge hole is provided on the support bottom cover directly above the drive gear, and the one-way valve is installed at the upward drilling fluid discharge hole; a first and second threaded sleeve are fixedly provided inside the outer push top cover; the first threaded sleeve is screwed into the first threaded sleeve, and the second threaded sleeve is screwed into the second threaded sleeve; a filter screen is provided at the outer openings of the first upward drilling fluid inlet, the second upward drilling fluid inlet, and the upward drilling fluid discharge hole.

2. The composite rotary steerable drilling offset device with auxiliary ejection function according to claim 1, characterized in that: There are four drilling fluid auxiliary channels, which are evenly distributed along the circumference. Each drilling fluid auxiliary channel is equipped with an external push mechanism and an internal push mechanism. Each external push mechanism is equipped with an auxiliary push mechanism. The outer sleeve shell adopts a four-petal combined splicing structure. Each single petal of the outer sleeve shell is provided with a drilling fluid auxiliary channel between it and the inner sleeve shell.

3. A composite rotary steerable drilling offset device with auxiliary ejection function according to claim 1, characterized in that: The main drilling fluid channel and the secondary drilling fluid channel are connected by a drilling fluid inlet hole, and the secondary drilling fluid channel is connected to the external space of the outer casing by a drilling fluid outlet hole.

4. A composite rotary steerable drilling offset device with auxiliary ejection function according to claim 3, characterized in that: A valve block is provided at the drilling fluid inlet. A power chamber is located between the inner and outer sleeve shells below the valve block. The power chamber houses the valve block actuator and a power battery. The valve block actuator includes a servo motor, a coupling, a ball screw, a nut slider, and a bearing seat. The servo motor is fixedly mounted in the power chamber. The motor shaft of the servo motor is coaxially connected to one end of the ball screw via the coupling. The nut slider is fitted onto the other end of the ball screw. The valve block and the nut slider are fixedly connected together. The ball screw is connected to the power chamber via a bearing seat. The servo motor is powered by a power battery.

5. A composite rotary steerable drilling offset device with auxiliary ejection function according to claim 1, characterized in that: The push mechanism includes a piston chamber and a push piston. The piston chamber is built into the outer sleeve shell, and the push piston is located in the piston chamber. The rodless chamber of the piston chamber is connected to the drilling fluid auxiliary flow channel, and the rod chamber of the piston chamber is connected to the external space of the outer sleeve shell. The piston rod of the push piston extends to the external space of the outer sleeve shell, and the auxiliary push mechanism is installed at the end of the piston rod of the push piston.

6. A composite rotary steerable drilling offset device with auxiliary ejection function according to claim 1, characterized in that: The internal pushing mechanism includes an active wedge, a driven wedge, and a buffer spring; an active wedge limiting groove is built into the outer sleeve shell, the active wedge is located in the active wedge limiting groove, and the buffer spring is disposed between the active wedge and the active wedge limiting groove; a driven wedge through hole is opened on the inner sleeve shell, and the driven wedge is inserted into the driven wedge through hole; the driven wedge is perpendicular to the active wedge, the outer end inclined surface of the driven wedge is in abutting contact with the lower end inclined surface of the active wedge, and a buffer pad is fixedly fitted on the rear drill bit shaft directly opposite the inner end of the driven wedge, and the inner end of the driven wedge is in abutting contact with the rear drill bit shaft through the buffer pad.

7. A composite rotary steerable drilling offset device with auxiliary ejection function according to claim 1, characterized in that: Lifting guide blind holes are provided at the four corners of the inner side of the supporting bottom cover, and lifting guide columns are provided at the four corners of the inner side of the outer push top cover. The lifting guide columns are inserted and guided by the lifting guide blind holes.

8. A composite rotary steerable drilling offset device with auxiliary ejection function according to claim 1, characterized in that: Both the first intermediate gear and the second intermediate gear have extended shaft structures. A first guide cylinder and a second guide cylinder are fixed inside the outer push-top cover. The extended section of the gear shaft of the first intermediate gear is inserted into and guided by the first guide cylinder. The extended section of the gear shaft of the second intermediate gear is inserted into and guided by the second guide cylinder.

9. A composite rotary steerable drilling offset device with auxiliary ejection function according to claim 5, characterized in that: The bottom center of the support cover is provided with a transition boss, and the top of the piston rod of the outward-pushing piston is provided with a transition groove. The support cover is fixedly connected to the transition groove at the top of the piston rod of the outward-pushing piston through the transition boss.

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