Reverse circulation rotary wing type casing-following drilling tool

Abstract

The utility model discloses a reverse circulation rotary wing type casing-following drilling tool which comprises a rotary wing drill bit, the rotary wing drill bit comprises a drill bit body and a reaming rotary wing, and the reaming rotary wing is configured to be rotationally connected with the front end of the drill bit body so that the reaming rotary wing can be in an unfolded state and a retracted state; the first air channel and the first channel are arranged in the drill bit body, and the first air channel is arranged on the outer side of the first channel; the reverse circulation assembly is in transmission connection with the rear end of the drill bit body, a high-pressure air channel and a center channel are arranged in the reverse circulation assembly, an outlet of the high-pressure air channel is communicated with the first air channel for exhausting, and the center channel is communicated with the first channel for discharging slag; and the protective pipe assembly is sleeved on the outer side of the reverse circulation assembly and is connected with the drill bit body. Compared with the prior art, the reverse circulation rotary wing type casing-following drilling tool can effectively solve the problems of hole shrinkage, collapse and hole wall instability of a soft soil layer, and is better in deslagging effect and more convenient to use.

Description

Technical Field

[0001] The present application relates to the technical field of drilling equipment, and more specifically, to a reverse circulation rotary vane pipe drilling tool. Background Art

[0002] When drilling in soft rock and soil layers that are loose, poorly cemented, easily broken, and easily hydrated, the construction is difficult, and problems such as coring difficulty, hole formation difficulty, and hole wall collapse are often encountered. The drilling effect is not ideal. The main reason is that the drilling process is prone to collapse while drilling, the amount of slag discharge is large, and accidents such as drill sticking, drill clamping, and drill burial may occur, resulting in low drilling efficiency.

[0003] The down-the-hole impactor and casing drilling technology fully utilizes the advantages of the down-the-hole impactor in efficiently impacting and crushing rocks. While drilling to efficiently crush rocks, the casing is followed to protect the borehole wall. The rigid guiding effect of the casing can suppress the bending of the borehole and ensure the straightness of the borehole. Therefore, the casing and casing expansion drilling tools are also widely used in engineering drilling construction in hard, broken, loose and other complex formations at home and abroad.

[0004] The down-the-hole hammer follow-the-hole drilling technology uses the drill pipe and the down-the-hole hammer to drive the drill tool to impact and rotate, driving the eccentric reaming head on the drill tool to rotate. The reaming head expands under the action of the eccentric force, so it is called a "rotor block reaming drill tool". The expanded diameter of the drill bit is larger than the outer diameter of the follow-the-hole and the pipe shoe, thereby achieving the purpose of hole expansion.

[0005] At present, rotary vane follow-through drilling tools mainly adopt positive circulation deslagging. However, when the hole diameter is large or the formation is complex, positive circulation deslagging is difficult, resulting in reduced drilling efficiency, shortened drill tool life and increased drilling costs. In addition, the drill bit is easily stuck by rock cuttings when lifting the drill, which brings inconvenience to the work of lifting the drill.

[0006] Therefore, there is an urgent need for a reverse circulation rotor-type pipe drill that can effectively solve the problems of shrinkage, collapse, and hole wall instability in soft soil layers, has better slag discharge effect, and is more convenient to use. Utility Model Content

[0007] In order to solve the above technical problems, the present application provides a reverse circulation rotor-type pipe drill, which can effectively solve the problems of shrinkage, collapse, and hole wall instability in soft soil layers, has better slag discharge effect, and is more convenient to use.

[0008] The technical solutions provided in this application are as follows:

[0009] A reverse circulation rotary vane casing drilling tool, comprising:

[0010] A rotary wing drill bit comprising a drill bit body and a reaming rotor, wherein the reaming rotor is configured to be rotatably connected to the front end of the drill bit body so that the reaming rotor has an extended state and a retracted state;

[0011] a first air passage and a first channel disposed in the drill body, wherein the first air passage is disposed outside the first channel;

[0012] a reverse circulation assembly drivingly connected to the rear end of the drill bit body, wherein a high-pressure air passage and a central passage are provided in the reverse circulation assembly, wherein the outlet of the high-pressure air passage is connected to the first air passage for exhaust, and the central passage is connected to the first passage for slag discharge;

[0013] A protective tube assembly is sleeved on the outside of the reverse circulation assembly and connected to the drill bit body.

[0014] Preferably, when the reaming rotor rotates around a first direction to an expanded state, the outer diameter of the reaming rotor is larger than the maximum outer diameter of the drill bit body; when the reaming rotor rotates around a second direction to a retracted state, the outer diameter of the reaming rotor is not larger than the maximum outer diameter of the drill bit body.

[0015] Preferably, the maximum outer diameter of the drill bit body is smaller than the inner diameter of the protective tube assembly, and the outer diameter of the reaming rotor in the retracted state is smaller than the inner diameter of the protective tube assembly.

[0016] Preferably, a receiving groove is provided on the front end surface of the drill body, a mounting hole is provided in the receiving groove, and a rotating shaft rotatably connected to the mounting hole is provided on the fixed side of the reaming rotor.

[0017] When the reaming rotor is in the expanded state, the fixed side of the reaming rotor abuts against one end of the accommodating groove, and the movable side of the reaming rotor extends in a direction away from the axis of the drill bit body;

[0018] When the reaming rotor is in a retracted state, the movable side of the reaming rotor is located in the accommodating groove.

[0019] Preferably, a locking shaft is provided along the radial direction of the drill body, and an avoidance groove is provided on the outer circumferential surface of the rotating shaft for use with the locking shaft. The locking shaft and the avoidance groove are used in conjunction with each other to enable the rotating shaft to rotate in the mounting hole.

[0020] Preferably, at least two reaming rotors are provided, and the reaming rotors are spaced apart along the circumference of the drill bit body.

[0021] Preferably, the protective tube assembly includes:

[0022] A pipe shoe, the pipe shoe being sleeved on the outside of the drill body, a positioning step being provided on the outer circumference of the drill body, and a positioning block being provided on the inner circumference of the pipe shoe, the rear end face of the positioning block being in contact with the front end face of the positioning step;

[0023] A heel tube is sleeved on the outer side of the rear end of the pipe shoe and fixedly connected to the pipe shoe.

[0024] Preferably, the reverse circulation component comprises:

[0025] A drill sleeve is sleeved on the outside of the drill body and is transmission-connected to the drill body, a second air passage is formed between the drill sleeve and the drill body, and a third air passage is provided on the drill sleeve for connecting the second air passage with the first air passage;

[0026] An outer sleeve is sleeved on the outside of the clamp sleeve and fixedly connected to the clamp sleeve;

[0027] A collection tube is sleeved in the outer sleeve, and the central channel is arranged in the collection tube;

[0028] a piston movably arranged between the collection tube and the outer sleeve;

[0029] A joint assembly is connected to the rear end of the outer sleeve, and a gas distribution channel for communicating with the second gas channel is formed among the joint assembly, the outer sleeve, the piston, the collection tube and the clamp sleeve.

[0030] Preferably, the first air channel is arranged to penetrate along the length direction of the drill body, and the reverse circulation assembly further comprises a plugging sleeve, which is arranged between the drill sleeve and the protective tube assembly, and is used to abut against the rear end face of the first air channel.

[0031] Preferably, a limiting step is provided on the outer circumference of the clamp sleeve, and a positioning block is provided on the inner circumference of the plug sleeve, the front end face of the positioning block abuts against the rear end face of the limiting step, and the rear end face of the positioning block abuts against the front end face of the outer sleeve.

[0032] The reverse circulation rotary vane pipe drilling tool provided by the present invention is provided with a rotary vane drill bit, a reverse circulation assembly, and a protective tube assembly. The rotary vane drill bit includes a drill bit body and a reaming rotor. The reaming rotor is rotatably connected to the front end of the drill bit body so that the reaming rotor has an expanded state and a retracted state. When the reaming rotor is in the expanded state, the reaming rotor is used to expand the hole. When the reaming rotor is in the retracted state, the reaming rotor is used to lift the drill. The reverse circulation assembly is transmission-connected to the rear end of the drill bit body for providing power to the rotary vane drill bit. The protective tube assembly is arranged on the outside of the reverse circulation assembly and is connected to the drill bit body. The reverse circulation assembly provides power to the rotary vane drill bit so that the rotary vane drill bit can drill a hole. As the rotary vane drill bit drills, the protective tube assembly is used to support the hole wall, which can effectively solve the problems of shrinkage, collapse, and hole wall instability in soft soil layers. When the aperture is large or the formation is complex, in order to facilitate slag discharge, the drill bit body of the present invention is provided with a first air channel and a first channel, the first air channel is provided on the outside of the first channel, and a high-pressure air channel and a central channel are provided in the reverse circulation assembly. The outlet of the high-pressure air channel is connected to the first air channel for exhaust, and the central channel is connected to the first channel for slag discharge. By using the rotary drill bit in conjunction with the reverse circulation assembly, exhaust is discharged from the side and slag is discharged in the middle during the drilling process, and the slag discharge effect is better. Since the residue at the bottom of the hole is discharged through the first channel and the central channel, the rotary drill bit can be prevented from being stuck by rock cuttings when the drill is lifted, and it is more convenient to use. It can be seen that compared with the prior art, the reverse circulation rotary drill bit in the embodiment of the present invention can effectively solve the problems of shrinkage, collapse, and hole wall instability in soft soil layers, has a better slag discharge effect, and is more convenient to use. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 any creative work.

[0034] Figure 1 A schematic structural diagram of a reverse circulation rotary vane casing drilling tool provided by an embodiment of the present utility model;

[0035] Figure 2 for Figure 1 A partial enlarged view of

[0036] Figure 3 A schematic structural diagram of a rotary wing drill bit provided in an embodiment of the present utility model (the reaming rotor is in an expanded state);

[0037] Figure 4A structural schematic diagram of a left view of a rotary wing drill bit provided in an embodiment of the present utility model (with the reaming rotors deployed);

[0038] Figure 5 A structural schematic diagram of a left view of a rotary wing drill bit provided in an embodiment of the present invention (with the reaming rotor retracted);

[0039] Figure 6 A schematic structural diagram of the hole-reaming rotor provided in an embodiment of the present utility model.

[0040] Figure numerals: 1. drill bit body; 2. reaming rotor; 3. reverse circulation assembly; 4. locking shaft; 5. pipe boot; 6. follower pipe; 7. second air channel; 8. third air channel; 11. first air channel; 12. first channel; 13. accommodating groove; 21. rotating shaft; 22. avoidance groove; 31. drill sleeve; 32. outer sleeve; 33. collection tube; 34. piston; 35. joint assembly; 36. plugging sleeve. DETAILED DESCRIPTION

[0041] In order to help those skilled in the art better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without making any creative efforts shall fall within the scope of protection of this application.

[0042] It should be noted that when an element is referred to as being “fixed on” or “set on” another element, it can be directly on the other element or indirectly set on the other element; when an element is referred to as being “connected to” another element, it can be directly connected to the other element or indirectly connected to the other element.

[0043] It should be understood that the terms "length", "width", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this application.

[0044] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of technical features indicated. Thus, a feature specified as "first" or "second" may explicitly or implicitly include one or more of such features. Throughout the description of this application, "plurality" or "several" means two or more, unless otherwise specifically defined.

[0045] It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which this application can be implemented. Therefore, they have no substantive technical significance. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in this application without affecting the efficacy and purpose that can be achieved by this application.

[0046] The embodiments of the present invention are written in a progressive manner.

[0047] like Figures 1 to 6 As shown, Figure 2 The single arrow in the figure indicates the direction of high-pressure airflow. Figure 2 The double arrows in the figure indicate the direction of flow of the residue at the bottom of the hole during slag discharge.

[0048] An embodiment of the present invention provides a reverse circulation rotary vane pipe-following drill tool, comprising: a rotary vane drill bit, the rotary vane drill bit comprising a drill bit body 1 and a reaming rotor 2, the reaming rotor 2 being configured as: rotatably connected to the front end of the drill bit body 1 so that the reaming rotor 2 has an expanded state and a retracted state; a first air duct 11 and a first channel 12 are arranged in the drill bit body 1, the first air duct 11 is arranged on the outside of the first channel 12; a reverse circulation component 3 transmission-connected to the rear end of the drill bit body 1, a high-pressure air duct and a central channel are arranged in the reverse circulation component 3, the outlet of the high-pressure air duct is connected to the first air duct 11 for exhaust, and the central channel is connected to the first channel 12 for slag discharge; a protective pipe component is sleeved on the outside of the reverse circulation component 3 and connected to the drill bit body 1.

[0049] It should be noted that the “front end” in this application refers to the end close to the bottom of the hole, and the “rear end” in this application refers to the end away from the bottom of the hole.

[0050] Current rotary vane follow-through drilling tools mainly use positive circulation to remove slag. However, when the hole diameter is large or the formation is complex, positive circulation to remove slag is difficult, resulting in reduced drilling efficiency, shortened drill tool life and increased drilling costs. In addition, the drill bit is easily stuck by rock cuttings when lifting the drill, which brings inconvenience to the work of lifting the drill.

[0051] The reverse circulation rotary vane pipe drilling tool provided by the present invention comprises a rotary vane drill bit, a reverse circulation assembly 3 and a protective tube assembly, wherein the rotary vane drill bit comprises a drill bit body 1 and a reaming rotor 2, the reaming rotor 2 being rotatably connected to the front end of the drill bit body 1 so that the reaming rotor 2 has an extended state and a retracted state. When the reaming rotor 2 is in the extended state, the reaming rotor 2 is used for reaming the hole, and when the reaming rotor 2 is in the retracted state, the reaming rotor 2 is used for lifting the drill. The reverse circulation assembly 3 is transmission-connected to the rear end of the drill bit body 1 for providing power to the rotary vane drill bit, the protective tube assembly is arranged on the outside of the reverse circulation assembly 3 and is connected to the drill bit body 1, and the reverse circulation assembly 3 provides power to the rotary vane drill bit so that the rotary vane drill bit can drill the hole. As the rotary vane drill bit drills, the protective tube assembly is used to support the hole wall, which can effectively solve the problems of shrinkage, collapse and hole wall instability in soft soil layers. When the aperture is large or the formation is complex, in order to facilitate slag discharge, the drill bit body 1 in the present invention is provided with a first air channel 11 and a first channel 12, the first air channel 11 is provided on the outside of the first channel 12, and the reverse circulation component 3 is provided with a high-pressure air channel and a central channel. The outlet of the high-pressure air channel is connected to the first air channel 11 for exhaust, and the central channel is connected to the first channel 12 for slag discharge. The rotary drill bit is used in conjunction with the reverse circulation component 3, and the exhaust is exhausted from the side and the slag is discharged in the middle during the drilling process, and the slag discharge effect is better. Since the residue at the bottom of the hole is discharged through the first channel 12 and the central channel, the rotary drill bit can be prevented from being stuck by rock cuttings when the drill is lifted, and it is more convenient to use. It can be seen that compared with the prior art, the reverse circulation rotary drill bit in the embodiment of the present invention can effectively solve the problems of shrinkage, collapse, and hole wall instability in soft soil layers, has a better slag discharge effect, and is more convenient to use.

[0052] In the above structure, as one of the specific implementation methods, the outlet of the first air channel 11 and the inlet of the first channel 12 in the embodiment of the utility model are both located on the front end face of the drill bit body 1, and the first air channel 11 is connected to the first channel 12. When the high-pressure gas is discharged from the first air channel 11, the residue at the bottom of the hole is blown into the first channel 12.

[0053] In the above structure, as one of the implementation modes, the front end surface of the rotary wing drill bit in the embodiment of the present invention is provided with alloy teeth, which are used for drilling.

[0054] More specifically, when the reaming rotor 2 rotates around the first direction to the expanded state, as shown in FIG. Figure 4 As described above, the outer diameter of the reaming rotor 2 is larger than the maximum outer diameter of the drill body 1. The reaming rotor 2 drives the drill body 1 to continue rotating in the first direction while the reverse circulation assembly 3 provides an axial pulse impact to the drill body 1, facilitating the reaming rotor 2 to reaming. When the reaming rotor 2 rotates around the second direction to the retracted state, as shown in FIG. Figure 5As shown, the outer diameter of the reaming rotor 2 is no greater than the maximum outer diameter of the drill bit body 1, facilitating the removal of the drill bit and the drill bit body 1 from the casing assembly. The first and second directions are opposite in direction. For example, if the first direction is clockwise, the second direction is counterclockwise; if the first direction is counterclockwise, the second direction is clockwise.

[0055] Furthermore, the maximum outer diameter of the drill body 1 in the embodiment of the present invention is smaller than the inner diameter of the protective tube assembly, so that the drill body 1 and the rotary wing drill bit can be easily withdrawn from the protective tube assembly when the rotary wing drill bit is in the retracted state.

[0056] In the above structure, the expansion and retraction connection structure between the reaming rotor 2 and the drill bit body 1 can adopt the structure of the positive circulation rotor follow-up drill bit in the prior art. In order to facilitate drilling and slag removal with the reverse circulation component 3, the first air duct 11 and the first channel 12 of the drill bit body 1 have been improved in applicability.

[0057] Furthermore, an embodiment of the present invention provides a specific structure of a rotary drill bit. The front end of the drill bit body 1 in the embodiment of the present invention is provided with a accommodating groove 13, and a mounting hole is provided in the accommodating groove 13. A rotating shaft 21 is provided on the fixed side of the reaming rotor 2, and the rotating shaft 21 is used to be rotatably connected to the mounting hole. When the reaming rotor 2 is in the expanded state, the fixed side of the reaming rotor 2 abuts against one end of the accommodating groove 13, and the reaming rotor 2 is limited by the end face of the accommodating groove 13. At this time, the movable side of the reaming rotor 2 extends in the axial direction away from the drill bit body 1, and the outer diameter of the reaming rotor 2 is larger than the maximum outer diameter of the drill bit body 1, which is convenient for reaming; when the reaming rotor 2 rotates in the opposite direction to the retracted state, the movable side of the reaming rotor 2 is located in the accommodating groove 13, which is convenient for lifting the drill.

[0058] Furthermore, in order to prevent the reaming rotor 2 from separating from the drill bit body 1, as one of the specific implementation methods, the reverse circulation pipe drilling tool in the embodiment of the utility model is also provided with a locking shaft 4, wherein the locking shaft 4 is arranged along the radial direction of the drill bit body 1, and an avoidance groove 22 is provided on the outer circumferential surface of the rotating shaft 21. The locking shaft 4 is used in conjunction with the avoidance groove 22 to enable the rotating shaft 21 to rotate in the mounting hole.

[0059] In the above structure, as one embodiment, at least two reaming rotors 2 are provided in the embodiment of the present invention, and the reaming rotors 2 are spaced apart along the axial direction of the drill bit body 1 .

[0060] More specifically, in the embodiment of the present invention, there are two reaming rotors 2 symmetrically arranged on both sides of the front end of the drill body 1 .

[0061] When a plurality of reaming rotor blades 2 are provided, the plurality of reaming rotor blades 2 are evenly spaced along the circumference of the front end of the drill bit body 1 .

[0062] In the above structure, as one embodiment, the pipe protection assembly in the embodiment of the present invention includes a pipe shoe 5 and a heel pipe 6, wherein the pipe shoe 5 is sleeved on the outside of the drill bit body 1, the outer peripheral side of the drill bit body 1 is provided with a positioning step, the inner peripheral side of the pipe shoe 5 is provided with a positioning block, the rear end face of the positioning block abuts the front end face of the positioning step, and the heel pipe 6 is sleeved on the outside of the rear end of the pipe shoe 5, and the heel pipe 6 is fixedly connected to the pipe shoe 5. The positioning step cooperates with the positioning block to locate the position of the drill bit body 1 moving toward the front end, and the heel pipe 6 and the pipe shoe 5 support the hole wall, which can effectively solve the problems of shrinkage, collapse, and hole wall instability in soft soil layers.

[0063] In the above structure, the outer circumference of the pipe shoe 5 in the embodiment of the present invention is provided with an external thread line, and the inner circumference of the heel tube 6 is provided with an internal thread line, and the pipe shoe 5 and the heel tube 6 are connected by threads.

[0064] In the above structure, as one embodiment, the reverse circulation assembly 3 in the embodiment of the present invention includes a drill sleeve 31, an outer sleeve 32, a collection pipe 33, a piston 34 and a joint assembly 35, wherein the drill sleeve 31 is sleeved on the outside of the rear end of the drill body 1, and the drill sleeve 31 is transmission-connected to the drill body 1. A second air passage 7 is formed between the inner wall of the drill sleeve 31 and the drill body 1. A third air passage 8 is provided on the drill sleeve 31. The third air passage 8 is used to connect the first air passage 11 and the second air passage 7. The outer sleeve 32 is sleeved on the outside of the drill sleeve 31, and the outer sleeve 32 and the drill sleeve 31 are fixedly connected. The collection pipe 33 is sleeved on the outside of the outer sleeve 32, and the central channel is provided in the collection pipe 33. 3, the central channel and the first channel 12 form a slag discharge channel. The piston 34 is movably arranged between the collection tube 33 and the outer sleeve 32. The piston 34 is used to separate the outer sleeve 32 and the collection tube 33 into a first air chamber and a second air chamber. There is a pressure difference between the first air chamber and the second air chamber, which is used to push the piston 34 to reciprocate along the axial direction, thereby providing a pulse force to the drill bit body 1 to facilitate drilling. The joint assembly 35 is arranged at the rear end of the outer sleeve 32. A gas distribution channel is formed among the joint assembly 35, the outer sleeve 32, the piston 34, the collection tube 33 and the drill sleeve 31. The gas distribution channel is used to communicate with the second air channel 7 and exhaust gas through the second air channel 7, the third air channel 8 and the first channel 12.

[0065] Furthermore, as one specific embodiment, the drill sleeve 31 is connected to the drill body 1 via a spline. High-pressure gas in the reverse circulation assembly 3 is discharged from the first gas channel 11 through the second gas channel 7 and the third gas channel 8, blowing the residue at the bottom of the hole to the first channel 12 and the center channel for slag removal.

[0066] In the above structure, the first air channel 11 in the embodiment of the present invention is arranged to penetrate along the length direction of the drill bit body 1. In order to avoid leakage of high-pressure gas from the rear end of the first air channel 11, as one of the preferred embodiments, the reverse circulation component 3 also includes a plugging sleeve 36. The plugging sleeve 36 is arranged between the protective tube assembly and the drill sleeve 31. The plugging sleeve 36 is fixedly connected to the outer sleeve 32. The plugging sleeve 36 is used to seal the rear end air outlet of the first air channel 11.

[0067] In the above structure, the plugging sleeve 36 and the outer sleeve 32 are fixedly connected in the following manner: a limiting step is provided on the outer circumference of the front end of the clamping sleeve 31, and a positioning block is provided on the inner circumference of the rear end of the plugging sleeve 36. The front end surface of the positioning block abuts against the positioning limiting step, and the rear end surface of the positioning block abuts against the outer sleeve 32. The outer sleeve 32 is fixedly connected to the clamping sleeve 31, thereby clamping the plugging sleeve 36.

[0068] More specifically, in the above structure, an internal thread is provided on the inner wall of the front end of the outer sleeve 32 in the embodiment of the utility model, and an external thread is provided on the outer wall of the clamp sleeve 31. The outer sleeve 32 and the clamp sleeve 31 are fixedly connected by threads, which makes disassembly and assembly more convenient.

[0069] The above description of the disclosed embodiments will enable one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be readily apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention is not limited to the embodiments shown herein but is intended to conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A reverse circulation rotary vane casing drilling tool, characterized in that: include: A rotary wing drill bit, comprising a drill bit body (1) and a reaming rotor (2), wherein the reaming rotor (2) is configured to be rotatably connected to the front end of the drill bit body (1) so that the reaming rotor (2) has an expanded state and a retracted state; A first air passage (11) and a first channel (12) are provided in the drill body (1), wherein the first air passage (11) is provided outside the first channel (12); A reverse circulation assembly (3) is connected to the rear end of the drill body in a transmission manner, wherein a high-pressure air passage and a central passage are provided in the reverse circulation assembly (3), wherein the outlet of the high-pressure air passage is connected to the first air passage (11) for exhaust, and the central passage is connected to the first passage (12) for slag discharge; A protective tube assembly is sleeved on the outside of the reverse circulation assembly (3) and connected to the drill bit body (1).

2. The reverse circulation rotary vane casing drilling tool according to claim 1, characterized in that: When the reaming rotor (2) rotates around a first direction to an extended state, the outer diameter of the reaming rotor (2) is larger than the maximum outer diameter of the drill bit body (1); when the reaming rotor (2) rotates around a second direction to a retracted state, the outer diameter of the reaming rotor (2) is not larger than the maximum outer diameter of the drill bit body (1).

3. The reverse circulation rotary vane casing drilling tool according to claim 2, characterized in that: The maximum outer diameter of the drill bit body (1) is smaller than the inner diameter of the protective tube assembly, and the outer diameter of the reaming rotor (2) when in a retracted state is smaller than the inner diameter of the protective tube assembly.

4. The reverse circulation rotary vane casing drilling tool according to any one of claims 1 to 3, characterized in that: A receiving groove (13) is provided on the front end surface of the drill bit body (1), a mounting hole is provided in the receiving groove (13), and a rotating shaft (21) rotatably connected to the mounting hole is provided on the fixed side of the hole-reaming rotor (2); When the reaming rotor (2) is in an expanded state, the fixed side of the reaming rotor (2) abuts against one end of the accommodating groove (13), and the movable side of the reaming rotor (2) extends in a direction away from the axis of the drill bit body (1); When the reaming rotor (2) is in a retracted state, the movable side of the reaming rotor (2) is located in the accommodating groove (13).

5. The reverse circulation rotary vane casing drilling tool according to claim 4, characterized in that: A locking shaft (4) is provided along the radial direction of the drill body (1), and an avoidance groove (22) for use with the locking shaft (4) is provided on the outer circumferential surface of the rotating shaft (21). The locking shaft (4) and the avoidance groove (22) are used in conjunction with each other to enable the rotating shaft (21) to rotate in the mounting hole.

6. The reverse circulation rotary vane casing drilling tool according to any one of claims 1 to 3 and 5, characterized in that: At least two reaming rotors (2) are provided, and the reaming rotors (2) are arranged at intervals along the circumference of the drill bit body (1).

7. The reverse circulation rotary vane casing drilling tool according to any one of claims 1 to 3 and 5, characterized in that: The protective tube assembly comprises: A pipe shoe (5), the pipe shoe (5) being sleeved on the outside of the drill body (1), a positioning step being provided on the outer peripheral side of the drill body (1), and a positioning block being provided on the inner peripheral side of the pipe shoe (5), the rear end face of the positioning block being in contact with the front end face of the positioning step; A heel tube (6) is sleeved on the outer side of the rear end of the tube shoe (5) and is fixedly connected to the tube shoe (5).

8. The reverse circulation rotary vane casing drilling tool according to any one of claims 1 to 3 and 5, characterized in that: The reverse circulation component (3) comprises: A clamping sleeve (31) is sleeved on the outside of the drill body (1) and is transmission-connected to the drill body (1), a second air passage (7) is formed between the clamping sleeve (31) and the drill body (1), and a third air passage (8) is provided on the clamping sleeve (31) for connecting the second air passage (7) and the first air passage (11); An outer sleeve (32) sleeved on the outside of the clamping sleeve (31) and fixedly connected to the clamping sleeve (31); a collection tube (33) sleeved within the outer sleeve (32), wherein the central channel is provided within the collection tube (33); a piston (34) movably disposed between the collection tube (33) and the outer sleeve (32); A joint assembly (35) is connected to the rear end of the outer sleeve (32), and a gas distribution channel for communicating with the second gas channel (7) is formed between the joint assembly (35), the outer sleeve (32), the piston (34), the collection tube (33) and the clamping sleeve (31).

9. The reverse circulation rotary vane casing drilling tool according to claim 8, characterized in that: The first air channel (11) is arranged to penetrate along the length direction of the drill bit body (1), and the reverse circulation assembly (3) further comprises a plugging sleeve (36), wherein the plugging sleeve (36) is arranged between the drill sleeve (31) and the protective tube assembly, and the plugging sleeve (36) is used to abut against the rear end face of the first air channel (11).

10. The reverse circulation rotary vane casing drilling tool according to claim 9, characterized in that: A limiting step is provided on the outer circumference of the clamping sleeve (31), and a positioning block is provided on the inner circumference of the blocking sleeve (36). The front end face of the positioning block abuts against the rear end face of the limiting step, and the rear end face of the positioning block abuts against the front end face of the outer sleeve (32).

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