A tool for preventing horizontal well collapse and drill sticking and its use method

Abstract

The present invention relates to the technical field of horizontal drilling, and in particular to a tool for preventing horizontal wells from collapsing and getting stuck, and a method for using the tool, comprising a lower housing, an upper housing, a power unit, a transmission shaft, and at least one set of crushing devices; each set of crushing devices comprises a transmission gear and two crushing gears meshing with the transmission gear at the same time, and crushing teeth are arranged on the periphery of the crushing gear; a plurality of crushing teeth are distributed and embedded on the periphery of the lower housing, and mounting cavities are also arranged on the lower housing; the transmission gear is connected to the transmission shaft; along the direction from the lower housing to the upper housing, the lower housing is in a variable diameter shape, comprising an outward expansion section and a retracted section, and the mounting cavities are all located on the outward expansion section; the circumferential force of the crushing teeth and the rotational extrusion force between the crushing gears break the rock blocks into small sizes, and the crushed rock blocks pass through the wellbore annulus and smoothly pass through the rotary guide tool with a larger radial size. The tool and the method for using the tool can effectively solve the problem of rock blocks getting stuck.

Description

Technical Field

[0001] The invention relates to the technical field of horizontal drilling, and in particular to a tool for preventing horizontal well collapse and drill sticking, and a use method thereof. Background Art

[0002] Horizontal drilling technology is one of the core technologies for shale gas development. It is widely used in shale gas development drilling due to its large single well volume and long production cycle. Due to the fragile nature of shale, the well wall becomes unstable after drilling to a certain depth, which easily leads to rock falling. In this case, it is easy to cause high friction and torque, drill sticking, drilling difficulties, etc.

[0003] In the prior art, a Chinese invention patent document with publication number CN107387003A and publication date November 24, 2017 was proposed to solve the above-mentioned technical problems. The technical solution disclosed in the patent document is as follows: A pulse jet valve for preventing borehole cuttings from getting stuck in the drill, belonging to the technical field of downhole tools for oil drilling. It consists of an outer shell, a rotating shaft, a valve wheel and an impeller; the outer shell is provided with a rotating shaft, the middle part of the rotating shaft is provided with a valve wheel, and the rotating shaft between the valve wheel and the upper bearing seat and the lower bearing seat is provided with an impeller; bypass holes are evenly distributed on the circumference of the outer shell corresponding to the valve wheel.

[0004] Although the above technical solution uses pulse jet to improve the migration efficiency of rock blocks in the horizontal well annulus and the cleanliness of the wellbore to a certain extent, during the current drilling construction process, although the circulation displacement is increased in the formation where rock blocks are prone to occur to ensure that the rock blocks are returned to the wellhead in time, due to the limited adjustment of the on-site drilling fluid displacement and the fact that rotary steering tools are often used in horizontal well drilling, the radial size of rotary steering tools is large, and large-sized rock blocks are not easy to pass through the wellbore annulus gap here, resulting in the deposition of rock blocks and cuttings at the front end of the rotary steering tool, which eventually evolves into a rock block stuck drill accident. Summary of the invention

[0005] In order to solve the above technical problems, the present invention proposes a tool for preventing horizontal well collapse and drill jamming and a method for using the tool, which breaks rock into pieces and reduces their size. The broken small-sized rock pieces are carried out of the wellhead by the drilling fluid, thereby improving the cleanliness of the wellbore and effectively solving the problem of rock block jamming.

[0006] The present invention is achieved by adopting the following technical solutions:

[0007] A tool for preventing horizontal wells from collapsing and getting stuck, characterized in that it comprises a lower shell, an upper shell, a power unit, a transmission shaft and at least one group of crushing devices; one end of the lower shell is connected to the drill bit, and one end of the upper shell is connected to a rotary guide tool; each group of crushing devices comprises a transmission gear and two crushing gears that mesh with the transmission gear at the same time, and the periphery of the crushing gear is provided with crushing teeth; a plurality of crushing teeth are distributed and embedded on the periphery of the lower shell, and the lower shell is also provided with mounting cavities for mounting the crushing gears; the transmission gear is connected to the transmission shaft, and the power unit drives the transmission shaft and the transmission gear to rotate, and further drives the two crushing gears in the same group to rotate relative to each other to squeeze and crush rock blocks; along the direction from the lower shell to the upper shell, the lower shell is in a variable diameter shape, including an outward expansion section and a retraction section, and the mounting cavities are all located on the outward expansion section.

[0008] One set of crushing devices is located between the expansion section and the retraction section.

[0009] Along the direction from the lower shell to the upper shell, the outer diameter of the transmission gear becomes smaller and the outer diameter of the crushing gear becomes larger.

[0010] The power device includes a stator and a rotor, which are a pair of conjugated spatial geometric bodies and mesh with each other to form a sealed cavity; the inner wall surface of the upper shell is in contact with the stator, and a first step surface for axial positioning of the stator is provided on the upper shell.

[0011] It also includes a jet device, which includes a triangular rotor, a drilling fluid inlet and a plurality of one-way jet valves arranged at intervals along the circumferential direction, and the one-way jet valve includes a valve body, a valve core, a spring and an oblique jet hole; the triangular rotor is connected to the rotor and forms a drilling fluid sealing chamber with the upper shell, and the rotation of the triangular rotor causes the volume of the drilling fluid sealing chamber to change periodically.

[0012] It also includes a connecting shaft, on which a drilling fluid through hole and a sealing ring groove are arranged, one end of the connecting shaft is connected to the transmission shaft, and the other end is connected to the rotor.

[0013] A connecting shell is also provided between the lower shell and the upper shell, and a groove is provided on one end of the connecting shell close to the lower shell for placing a sealing ring.

[0014] It also includes a bearing, the transmission shaft is provided with a second step surface for installing the bearing, the interior of the upper shell is provided with a third step surface for axial positioning of the bearing, and the connecting shell is provided with a fourth step surface for bearing positioning.

[0015] The crushing gear is a bevel gear, and transmission teeth meshing with the crushing teeth are arranged on both sides of the transmission gear.

[0016] A method for using a tool to prevent horizontal well collapse and drill bit jamming, characterized in that: the two ends of the tool are respectively connected to a rotary guide tool and a drill bit, a power device drives the transmission shaft to rotate, and the transmission gears are respectively engaged with the crushing gears to transmit power; during the drilling process, the lower shell rotates accordingly, and in the process of rock blocks moving from the lower shell to the upper shell, due to the variable diameter of the lower shell, the rock blocks are broken step by step, and the circumferential force of the crushing teeth and the rotational extrusion force between the crushing gears break the rock blocks into small sizes, and the broken rock blocks pass smoothly through the rotary guide tool with a larger radial size through the wellbore annulus; at the same time, the drilling fluid enters the drilling fluid sealing chamber through the drilling fluid inlet, and the volume of the drilling fluid sealing chamber changes periodically under the drive of the triangular rotor, and the drilling fluid is injected into the one-way jet valve to form a pulse jet, and the broken rock leaves the wellbore annulus under the action of the pulse jet.

[0017] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0018] 1. Through the tool and the method for using the tool, the crushing teeth and the crushing gear can effectively crush the rock blocks generated by the drill bit, improve the crushing efficiency of the rock blocks in the annulus of the horizontal well, make the size of the rock blocks smaller after crushing, and can effectively pass through the rotary guide tool with a larger radial size, so as to prevent the occurrence of rock block jamming accidents.

[0019] In the process of rock blocks moving from the lower shell to the upper shell, the lower shell is in a variable diameter shape, so that the outer surface of the lower shell is an inclined surface, and the installation cavity is located on the expansion section, so that the rock blocks can be broken step by step and broken multiple times. The strong circumferential force of the crushing teeth and the rotational extrusion force between the crushing gears work together to better crush the rock blocks. And only when the size of the crushed rock blocks is smaller than the set size, which is the distance between the crushing gear and the well wall, can the rock blocks pass through the crushing device, making the crushing of the rock blocks more thorough and more accurate.

[0020] 2. One set of crushing devices is located between the expansion section and the retraction section, which makes the crushing effect of the crushing device better and can better control the maximum size of the rock after breaking.

[0021] 3. Along the direction from the lower shell to the upper shell, the outer diameter of the crushing gear increases successively. When the transmission shaft rotates one circle, the crushing gear with a small outer diameter rotates more circles than the crushing gear with a large outer diameter. The drilling speed of the crushing gear decreases successively with the increase of the outer diameter of the crushing gear, so that the crushing gear has a better effect in initially crushing rock blocks.

[0022] 4. It also includes a jet device, which generates a pulse jet through a one-way jet valve and uses hydraulic shock waves to greatly enhance the displacement of rock fragments in the wellbore annulus, reduce the retention time of rock fragments in the wellbore annulus, effectively prevent drill sticking accidents, significantly improve drilling efficiency, improve wellbore cleanliness, and extend the service life of drilling tools.

[0023] 5. This tool converts liquid energy into kinetic energy through a power device, which can provide a large crushing force to actively break rock blocks. During the drilling process, the drill bit drives the crushing teeth, and the transmission shaft drives the crushing gears. The two work simultaneously, which is convenient and efficient.

[0024] 6. The installation and use of bearings can support the transmission shaft, reduce the friction coefficient during its movement, and ensure the rotation accuracy. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments, wherein:

[0026] Figure 1 It is a structural schematic diagram of the present invention;

[0027] Figure 2 It is a schematic diagram of the cross-sectional structure of AA;

[0028] Figure 3 It is a structural schematic diagram of the one-way jet valve of the present invention;

[0029] Figure 4 It is a structural schematic diagram of the lower shell of the present invention;

[0030] Figure 5 It is a structural schematic diagram of the connecting shaft of the present invention;

[0031] Figure 6 The schematic diagram of the overall crushing of the present invention (wherein L represents the specified size of rock falling and crushing);

[0032] Figure 7 It is a schematic diagram of the crushing of the crushing gear of the present invention;

[0033] Figure 8 It is a schematic structural diagram of the crushing gear of the present invention;

[0034] Fig. 9 It is a three-dimensional structural schematic diagram of the transmission gear of the present invention;

[0035] Fig.10 It is a schematic elevational structural diagram of the transmission gear of the present invention;

[0036] Markings in the figure:

[0037] 1. Lower housing, 2. Crushing teeth, 3. First-stage crushing gear, 4. Second-stage crushing gear, 5. Third-stage crushing gear, 6. Flat key, 7. Connecting housing, 8. Deep groove ball bearing, 9. Drilling fluid through hole, 10. One-way jet valve, 11. Stator, 12. Rotor, 13. Upper connecting thread, 14. Upper housing, 15. Triangular rotor, 16. Connecting shaft, 17. Sealing ring, 18. Third-stage transmission gear, 19. Second-stage transmission gear, 20. First-stage transmission gear, 21. Transmission shaft, 22. Lower connecting Thread, 23, well wall, 24, rock falling, 1a, first installation cavity, 1b, second installation cavity, 1c, third installation cavity, 3a, crushing teeth, 3b, contact end face, 10a, spring, 10b, valve body, 10c, jet hole, 10d, valve core, 14a, internal thread, 14b, sealing ring groove, 14c, external thread, 15a, connecting key hole, 15b, drilling fluid inlet, 15c, drilling fluid sealing cavity, 15d, drilling fluid outlet, 18a, key mouth, 18b, transmission teeth. DETAILED DESCRIPTION

[0038] Example 1

[0039] As a basic embodiment of the present invention, the present invention includes a tool for preventing horizontal well collapse and drill jamming, including a lower shell 1, an upper shell 14, a power unit, a transmission shaft 21 and a group of crushing devices. One end of the lower shell 1 is connected to the drill bit, and one end of the upper shell 14 is connected to the rotary guide tool. Each group of crushing devices includes a transmission gear and two crushing gears that are meshed with the transmission gear at the same time, and the periphery of the crushing gear is provided with crushing teeth 3a. A plurality of crushing teeth 2 are distributed and embedded on the periphery of the lower shell 1, and the lower shell 1 is also provided with mounting cavities for installing crushing gears. The transmission gear is connected to the transmission shaft 21, and the power unit can be a motor, which drives the transmission shaft 21 and the transmission gear to rotate, and further drives the two crushing gears in the same group to rotate with each other to squeeze and crush rock blocks 24. Along the direction from the lower shell 1 to the upper shell 14, the lower shell 1 is in a variable diameter shape, including an outward expansion section and a retracted section. The installation cavity is located on the outward expansion section. The minimum distance between the outward expansion section and the well wall 23 is the specified size for the rock blocks 24 to be crushed, which is also the maximum size of the rock blocks 24 after being crushed. By controlling the specified size for crushing, the maximum size of the rock blocks 24 can also be controlled to avoid the rock blocks 24 being stuck at the maximum radial size of the rotary guide tool.

[0040] Example 2

[0041] As a preferred embodiment of the present invention, the present invention includes a tool for preventing horizontal well collapse and drill bit jamming, including a lower shell 1, an upper shell 14, a power device, a transmission shaft 21, a jet device and two sets of crushing devices. One end of the lower shell 1 is connected to the drill bit, and one end of the upper shell 14 is connected to the rotary guide tool. The power device includes a stator 11 and a rotor 12, and the stator 11 and the rotor 12 are a pair of conjugated spatial geometric bodies, which are meshed with each other to form a sealed cavity.

[0042] Each set of crushing devices includes a transmission gear and two crushing gears meshing with the transmission gear at the same time. The crushing gear is a bevel gear, the periphery of the crushing gear is provided with crushing teeth 3a, and both sides of the transmission gear are provided with transmission teeth 18b meshing with the crushing teeth 3a.

[0043] A plurality of crushing teeth 2 are embedded in the periphery of the lower shell 1, and mounting cavities for mounting crushing gears are also provided on the lower shell 1. The transmission gear is connected to the transmission shaft 21, and the power device drives the transmission shaft 21 and the transmission gear to rotate, and further drives the two crushing gears in the same group to rotate with each other to crush the rock blocks 24. Along the direction from the lower shell 1 to the upper shell 14, the lower shell 1 is in a variable diameter shape, including an outward expansion section and a retracted section. The mounting cavities are all located on the outward expansion section, and the two groups of crushing gears are sequentially arranged on the outward expansion section.

[0044] The jet device includes a triangular rotor 15 and a plurality of one-way jet valves 10 arranged at intervals along the circumferential direction. The one-way jet valve 10 includes a valve body 10b, a valve core 10d, a spring 10a and an oblique jet hole 10c. The triangular rotor 15 is connected to the rotor 12 and forms a drilling fluid sealing chamber 15c with the upper shell 14. The rotation of the triangular rotor 15 causes the volume of the drilling fluid sealing chamber 15c to change periodically. When the drilling fluid pressure is greater than the threshold set by the spring 10a, the drilling fluid forms a jet through the oblique jet hole 10c, and the valve core 10d is periodically opened and closed to form a pulse jet.

[0045] Example 3

[0046] As another preferred embodiment of the present invention, the present invention includes a tool for preventing horizontal well collapse and drill jamming, comprising a lower shell 1, an upper shell 14, a power device, a transmission shaft 21 and four sets of crushing devices. One end of the lower shell 1 is connected to the drill bit, and one end of the upper shell 14 is connected to the rotary guide tool.

[0047] Each set of crushing devices includes a transmission gear and two crushing gears meshing with the transmission gear at the same time. The periphery of the crushing gear is provided with crushing teeth 3a. The periphery of the lower shell 1 is distributed with a plurality of crushing teeth 2, and the lower shell 1 is also provided with mounting cavities for mounting the crushing gears. The transmission gear is connected to the transmission shaft 21, and the power device drives the transmission shaft 21 and the transmission gear to rotate, and further drives the two crushing gears in the same group to rotate relative to each other to squeeze and crush the rock pieces 24.

[0048] Along the direction from the lower shell 1 to the upper shell 14, the lower shell 1 is in a variable diameter shape, including an expansion section and a retraction section, the installation chambers are all located on the expansion section, and the outer diameter of the transmission gear becomes smaller and smaller, and the outer diameter of the crushing gear becomes larger and larger. Along the direction from the lower shell 1 to the upper shell 14, the distance between the four groups of crushing gears and the well wall 23 becomes smaller and smaller. When one group of crushing devices is located between the expansion section and the retraction section, the distance between the crushing gear and the well wall 23 reaches the minimum, which is the specified size for the crushing of rock blocks 24.

[0049] Example 4

[0050] As the best embodiment of the present invention, refer to the attached specification Figure 1 The present invention includes a tool for preventing horizontal well collapse and drill bit jamming, including a housing part, a power device, a connecting shaft 16, a transmission shaft 21, a crushing tooth 2, a bearing, a sealing ring 17, a flat key 6, a triangular rotor 15, a jet device and three sets of crushing devices. The housing part includes an upper housing 14, a lower housing 1 and a connecting housing 7, wherein both ends of the connecting housing 7 are provided with threads for connecting the upper housing 14 and the lower housing 1, the connecting housing 7 is provided with a fourth step surface for positioning the deep groove ball bearing 8, and a groove is provided near one end of the lower housing 1 for placing the sealing ring 17.

[0051] The power device comprises a stator 11 and a rotor 12, which are a pair of conjugated spatial geometric bodies that mesh with each other to form a sealed cavity. The rotor 12 is a screw. Figure 5 The connecting shaft 16 has an internal thread 14a at one end connected to the transmission shaft 21, and an external thread 14c at the other end connected to the rotor 12. The connecting shaft 16 has a drilling fluid through hole 9 for the circulation of drilling fluid, and a sealing ring groove 14b is provided on the connecting shaft 16.

[0052] The inner wall of the upper shell 14 contacts the stator 11, and a first step surface is provided to realize the axial positioning of the stator 11. A third step surface for axial positioning of the bearing is provided inside the upper shell 14. An upper connecting thread 13 is provided at one end of the upper shell 14 for connecting with a rotary guide tool.

[0053] Refer to the instruction manual Figures 8-10Each group of crushing devices includes a transmission gear and two crushing gears that mesh with the transmission gear at the same time. The crushing gear is a bevel gear, and the outer periphery of the crushing gear is provided with crushing teeth 3a. The transmission gear is provided with transmission teeth 18b that mesh with the crushing teeth 3a on both sides. In this embodiment, it specifically includes a primary crushing gear 3, a secondary crushing gear 4, a tertiary crushing gear 5, a tertiary transmission gear 18, a secondary transmission gear 19 and a primary transmission gear 20. The contact end face 3b of the primary crushing gear 3 is in contact with the lower shell 1, and the crushing teeth 3a and the transmission teeth 18b are meshed with each other to realize transmission. The contact and transmission of the secondary crushing gear 4 and the tertiary crushing gear 5 are the same as those of the primary crushing gear 3.

[0054] A keyway is provided at the position of the transmission shaft 21 corresponding to the transmission gear, and a key opening 18a is provided on the transmission gear. The transmission shaft 21 is connected to the primary transmission gear 20, the secondary transmission gear 19 and the tertiary transmission gear 18 through a flat key 6. A groove is provided on the contact surface between the transmission shaft 21 and the lower housing 1 to install the sealing ring 17. The bearing can be a deep groove ball bearing 8, and the transmission shaft 21 is provided with a second step surface for installing the deep groove ball bearing 8.

[0055] Refer to the instruction manual Figure 4 , both ends of the lower shell 1 are provided with threads, one end is connected to the drill bit through the lower connecting thread 22, and the other end is connected to the connecting shell 7. Along the direction from the lower shell 1 to the upper shell 14, the lower shell 1 is in a variable diameter shape, including an outward expansion section and a retraction section. Crushing teeth 2 are distributed and embedded on the periphery of the lower shell 1, and installation cavities for placing crushing gears are sequentially provided in the outward expansion section, specifically including a first installation cavity 1a, a second installation cavity 1b and a third installation cavity 1c, which are respectively used to install a first-stage crushing gear 3, a second-stage crushing gear 4 and a third-stage crushing gear 5. The installation cavity varies according to the size of the crushing gear. Along the direction from the lower shell 1 to the upper shell 14, the outer diameters of the first-stage crushing gear 3, the second-stage crushing gear 4 and the third-stage crushing gear 5 become larger in sequence, and the outer diameters of the first-stage transmission gear 20, the second-stage transmission gear 19 and the third-stage transmission gear 18 become smaller in sequence. The tertiary crushing gear 5 can be located between the expansion section and the retraction section, so that the distance between the tertiary crushing gear 5 and the well wall 23 is minimized. This distance is also the specified size L for the rock blocks 24 to be crushed. Rocks larger than this size cannot pass through the crushing device.

[0056] Refer to the instruction manual Figure 2 And the instruction manual Figure 3The jet device includes a triangular rotor 15, a drilling fluid inlet 15b, a drilling fluid outlet 15d and four one-way jet valves 10 arranged at intervals along the circumferential direction. The triangular rotor 15 is connected to the rotor 12 through a connecting key hole 15a, and forms a drilling fluid sealing chamber 15c with the upper shell 14. The rotation of the triangular rotor 15 causes the volume of the drilling fluid sealing chamber 15c to change periodically. The one-way jet valve 10 includes a valve body 10b, a valve core 10d, a spring 10a and an oblique jet hole 10c. When the drilling fluid pressure is greater than the threshold set by the spring 10a, the drilling fluid passes through the jet hole 10c to form a jet, and the valve core 10d is periodically opened and closed to form a pulse jet.

[0057] When in use, the tool is connected to the rotary guide tool through the upper connecting thread 13, and is connected to the drill bit through the lower connecting thread 22. When the drilling fluid flows into the tool through the rotary guide tool, due to the pressure difference, the rotor 12 will rotate around the stator 11 as an axis. The drilling fluid passes through the stator 11 and the rotor 12 and enters the inside of the connecting shaft 16 through the drilling fluid through hole 9, and finally reaches the drill bit part along the inside of the transmission shaft 21. The rotation of the rotor 12 drives the connecting shaft 16 to rotate. The connecting shaft 16 is connected to the transmission shaft 21 through a thread. The transmission shaft 21 and the first-stage transmission gear 20, the first-stage transmission gear 20, and the first-stage transmission gear 20 are connected through a flat key 6. The third-stage transmission gear 18, the second-stage transmission gear 19, and the first-stage transmission gear 20 are respectively meshed with the corresponding first-stage crushing gear 3, the second-stage crushing gear 4, and the third-stage crushing gear 5 to transmit power. Refer to the attached manual Figure 7 The first-stage crushing gear 3, the second-stage crushing gear 4, and the third-stage crushing gear 5 crush the rock pieces 24 through the crushing teeth 3a. During the drilling process, the lower shell 1 rotates accordingly, and the crushing teeth 2 arranged on the lower shell 1 rotate to crush the rock pieces 24. During the movement of the rock pieces 24 from the lower shell 1 to the upper shell 14, the lower shell 1 is a variable diameter, resulting in the tool having an inclined surface. Figure 6 The rock pieces 24 are broken step by step. The strong circumferential force of the breaking teeth 2 and the rotational extrusion force between the first-stage breaking gear 3, the second-stage breaking gear 4 and the third-stage breaking gear 5 break the rock pieces 24 into small sizes. The broken rock pieces 24 can pass through the wellbore annulus smoothly through the rotary guide tool with a larger radial size. The drilling fluid enters the drilling fluid sealing chamber 15c through the drilling fluid inlet 15b. Driven by the triangular rotor 15, the volume changes periodically, and the drilling fluid is pumped into the one-way jet valve 10 to form a pulse jet. The broken rock pieces 24 quickly leave the wellbore annulus under the action of the pulse jet, thereby achieving the purpose of improving the migration speed of the rock pieces 24 in the horizontal well annulus and the wellbore cleanliness, and can effectively prevent the occurrence of drill sticking accidents.

[0058] In summary, after reading the present invention document, ordinary technicians in this field can make various other corresponding transformation schemes based on the technical scheme and technical concept of the present invention without creative mental labor, which all fall within the scope of protection of the present invention.

Claims

1. A tool to prevent horizontal well collapse and drill bit sticking, characterized by: The invention comprises a lower shell (1), an upper shell (14), a power device, a transmission shaft (21) and at least one set of crushing devices; one end of the lower shell (1) is connected to a drill bit, and one end of the upper shell (14) is connected to a rotary guide tool; each set of crushing devices comprises a transmission gear and two crushing gears meshing with the transmission gear at the same time, and the periphery of the crushing gear is provided with crushing teeth (3a); a plurality of crushing teeth (2) are distributed and embedded on the periphery of the lower shell (1), and the lower shell (1) is also provided with mounting cavities for mounting the crushing gears; the transmission gear is connected to the transmission shaft (21), and the power device drives the transmission shaft (21) and the transmission gear to rotate, and further drives the two crushing gears in the same set to rotate relative to each other to squeeze and crush rock pieces (24); along the direction from the lower shell (1) to the upper shell (14), the lower shell (1) is in a variable diameter shape, comprising an outward expansion section and a retracted section, and the mounting cavities are all located on the outward expansion section.

2. A tool for preventing horizontal well collapse and drill bit sticking according to claim 1, characterized in that: One set of crushing devices is located between the expansion section and the retraction section.

3. A tool for preventing horizontal well collapse and drill bit sticking according to claim 2, characterized in that: Along the direction from the lower shell (1) to the upper shell (14), the outer diameter of the transmission gear gradually decreases, and the outer diameter of the crushing gear gradually increases.

4. A tool for preventing horizontal well collapse and drill sticking according to claim 3, characterized in that: The power device comprises a stator (11) and a rotor (12), wherein the stator (11) and the rotor (12) are a pair of conjugated spatial geometric bodies that mesh with each other to form a sealed cavity; the inner wall surface of the upper shell (14) is in contact with the stator (11), and the upper shell (14) is provided with a first step surface for axial positioning of the stator (11).

5. A tool for preventing horizontal well collapse and drill sticking according to claim 4, characterized in that: The invention also comprises a jet device, the jet device comprising a triangular rotor (15), a drilling fluid inlet (15b) and a plurality of one-way jet valves (10) arranged at intervals along the circumferential direction, the one-way jet valve (10) comprising a valve body (10b), a valve core (10d), a spring (10a) and an oblique jet hole (10c); the triangular rotor (15) is connected to the rotor (12) and forms a drilling fluid sealing chamber (15c) with the upper shell (14); the triangular rotor (15) rotates to cause the volume of the drilling fluid sealing chamber (15c) to change periodically.

6. A tool for preventing horizontal well collapse and drill sticking according to claim 4, characterized in that: It also comprises a connecting shaft (16), on which a drilling fluid through hole (9) and a sealing ring groove (14b) are provided, one end of the connecting shaft (16) being connected to the transmission shaft (21), and the other end being connected to the rotor (12).

7. A tool for preventing horizontal well collapse and drill sticking according to claim 1, characterized in that: A connecting shell (7) is further provided between the lower shell (1) and the upper shell (14), and a groove is further provided at one end of the connecting shell (7) close to the lower shell (1) for accommodating a sealing ring (17).

8. A tool for preventing horizontal well collapse and drill sticking according to claim 1, characterized in that: It also includes a bearing, the transmission shaft (21) is provided with a second step surface for mounting the bearing, the interior of the upper housing (14) is provided with a third step surface for axial positioning of the bearing, and the connecting housing (7) is provided with a fourth step surface for positioning the bearing.

9. A tool for preventing horizontal well collapse and drill bit sticking according to claim 1, characterized in that: The crushing gear is a bevel gear, and transmission teeth (18b) meshing with the crushing teeth (3a) are provided on both sides of the transmission gear.

10. The method for using the tool for preventing horizontal well collapse and drill sticking according to claim 5, characterized in that: The two ends of the tool are respectively connected to the rotary steering tool and the drill bit, and the power device drives the transmission shaft (21) to rotate, and the transmission gears are respectively meshed with the crushing gears to transmit power. During the drilling process, the lower shell (1) rotates accordingly. In the process of the rock pieces (24) moving from the lower shell (1) to the upper shell (14), due to the variable diameter of the lower shell (1), the rock pieces (24) are broken step by step. The circumferential force of the crushing teeth (2) and the rotational extrusion force between the crushing gears break the rock pieces (24) into small sizes. The broken rock pieces (24) pass smoothly through the rotary steering tool with a larger radial size through the wellbore annulus. At the same time, the drilling fluid enters the drilling fluid sealing chamber (15c) through the drilling fluid inlet (15b). Driven by the triangular rotor (15), the volume of the drilling fluid sealing chamber (15c) changes periodically, and the drilling fluid is injected into the one-way jet valve (10) to form a pulse jet. The broken rock leaves the wellbore annulus under the action of the pulse jet.

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