Air lift reverse circulation double-wall drilling tool used in cooperation with air compressor

Abstract

The utility model discloses an air lift reverse circulation double-wall drilling tool used in cooperation with an air compressor, and relates to the field of drilling equipment. The device comprises an outer pipe and an inner pipe which are coaxially arranged, the inner pipe comprises an inner sleeve and an outer sleeve which are coaxially and detachably connected in a sleeved mode, the bottom face of the inner sleeve protrudes out of the bottom face of the outer sleeve, the top face of the outer sleeve protrudes out of the top face of the inner sleeve, and the protruding height of the top face of the outer sleeve is not larger than that of the bottom face of the inner sleeve; alignment rings are evenly arranged on the outer sleeve in the height direction, the alignment rings are in threaded connection with the inner pipe wall of the outer pipe, and circulation holes are evenly formed in the alignment rings in the circumferential direction. The utility model has the beneficial effects that the inner pipe is formed by sleeving the outer sleeve and the inner sleeve, the strength of the inner pipe is enhanced, and the outer convex structures of the outer sleeve and the inner sleeve form a plug-in structure, so that the inner pipe is convenient to disassemble and maintain, the disassembly and maintenance efficiency is improved, and the use flexibility and high efficiency are ensured.

Description

Technical Field

[0001] This utility model relates to the field of drilling equipment, specifically to the field of air-lift reverse circulation drilling tools, and particularly to air-lift reverse circulation double-wall drilling tools used in conjunction with air compressors. Background Technology

[0002] Air-lift reverse circulation drilling is a highly efficient drilling method that utilizes an air compressor to precisely deliver compressed air through an air supply line, the double-walled active drill pipe, and the annular space of the double-walled drill pipe to the mixing chamber inside the drill string. This compressed air then enters the inner tube of the double-walled drill pipe, where it mixes thoroughly with the existing flushing fluid and drilled cuttings, forming a mixture with a lower density than the flushing fluid. Due to its lower density, this mixture causes a significant drop in the fluid column pressure inside the drill pipe, creating a distinct pressure difference between the inside and outside of the drill pipe. This pressure difference drives the mixture to rise within the drill pipe and eventually exit.

[0003] The inner tube of a double-walled drill pipe is typically a single-tube structure, which is susceptible to damage when transporting flushing fluid and rock cuttings. This is especially true when the inner tube is connected via a plug-in joint; frequent plugging and unplugging causes wear at the joint, interfering with the normal use of the double-walled drill pipe. Furthermore, current maintenance procedures are inconvenient, both in terms of disassembly and assembly, significantly reducing maintenance efficiency. Utility Model Content

[0004] This invention addresses the technical problem of low operational efficiency caused by the inconvenience of disassembling and maintaining the inner tube of double-walled drill pipes by providing an air-lift reverse circulation double-walled drill tool for use with an air compressor. The inner tube is composed of an outer tube and an inner sleeve, which enhances the strength of the inner tube. The protruding structures of the outer tube and the inner sleeve form a plug-in structure, facilitating disassembly and maintenance, improving disassembly and maintenance efficiency, and ensuring flexibility and high efficiency in use.

[0005] The technical solution adopted by this utility model is as follows: a double-walled air-lift reverse circulation drill bit for use with an air compressor is provided, including an outer tube and an inner tube arranged coaxially. The inner tube includes an inner sleeve and an outer sleeve that are coaxially and detachably sleeved. The bottom surface of the inner sleeve protrudes from the bottom surface of the outer sleeve, and the top surface of the outer sleeve protrudes from the top surface of the inner sleeve. The protrusion height of the top surface of the outer sleeve is not greater than the protrusion height of the bottom surface of the inner sleeve. Alignment rings are uniformly arranged along the height direction on the outer sleeve. The alignment rings are threadedly connected to the inner tube wall of the outer tube, and flow holes are provided along the circumferential direction on the alignment rings.

[0006] The inner tube consists of an outer tube and an inner sleeve. The top surface of the outer tube protrudes beyond the top surface of the inner sleeve, while the bottom surface of the inner sleeve protrudes beyond the bottom surface of the inner sleeve. The outer tube is then placed inside the outer tube, and the alignment ring on the outer tube is threaded onto the outer tube, thus assembling the inner tube onto the outer tube. Assembly is simple. When assembling and using double-walled drill pipes, after threading the outer tubes on each double-walled drill pipe, the inner sleeve is inserted into the outer tube on the other double-walled drill pipe, and the protrusion height of the top surface of the outer tube is not greater than the protrusion height of the bottom surface of the inner sleeve. To ensure the reliability of the connection, the assembly of the double-walled drill pipe is completed. During air-lift reverse circulation drilling, the air compressor is connected to the double-walled drill pipe through pipelines. After the drilling fluid and compressed air are mixed, they are introduced into the passage between the outer tube and the outer sleeve of the double-walled drill pipe, and flow along the flow holes on the alignment ring to be transported downhole. The drill fluid also carries rock cuttings into the inner sleeve and transports the rock cuttings upward to the external sedimentation tank. The assembly of the outer sleeve and the inner sleeve on the inner tube enhances the strength of the inner tube and ensures its reliability.

[0007] To further optimize this technical solution, the outer sleeve and the inner sleeve are threadedly connected, and a positioning ring is provided on the inner wall of the outer sleeve. The top surface of the inner sleeve abuts against the positioning ring, and the positioning ring is locked to the inner sleeve by means of a locking member.

[0008] The outer sleeve and the inner sleeve are assembled by threaded connection. After the inner sleeve abuts against the positioning ring, the outer sleeve and the inner sleeve are assembled in place, and the locking device ensures the firmness of the assembly of the outer sleeve and the inner sleeve.

[0009] To further optimize this technical solution, the locking component includes a bolt threaded onto the positioning ring, and the bolt is threaded onto the inner sleeve.

[0010] The positioning ring is secured to the inner sleeve with bolts, making operation simple and reliable.

[0011] To further optimize this technical solution, the top surface of the bolt is flush with the top surface of the positioning ring, and sealing gaskets are provided on both the upper and lower end faces of the positioning ring.

[0012] The top surface of the bolt is flush with the top surface of the locating ring, so that the sealing gasket is not interfered with and the reliability of the seal is guaranteed.

[0013] To further optimize this technical solution, the inner ring wall of the positive ring is welded and fixed to the outer tube wall of the outer sleeve.

[0014] The welding and fixing of the positive ring and the outer sleeve ensures a firm assembly and stable and reliable use.

[0015] To further optimize this technical solution, the upper and lower parts of the inner wall of the outer tube are provided with connecting grooves, and elastic retaining rings are provided in the connecting grooves. The elastic retaining rings abut against the end face of the alignment ring.

[0016] By inserting an elastic retaining ring into the connecting groove, and having it abut against the end face of the alignment ring, the assembly of the inner tube and the outer tube is ensured to be firm and reliable.

[0017] To further optimize this technical solution, the inner wall of the outer tube is provided with external threads corresponding to the position and number of the alignment rings along the height direction, and each alignment ring is provided with an internal thread that matches the external threads.

[0018] The internal thread on the positive ring does not interfere with its movement along the inner wall of the outer tube, and the positive ring is threaded together with the external thread of the outer tube after contact, making the operation simple.

[0019] The beneficial effects of this utility model are as follows:

[0020] 1. The inner tube consists of an outer tube and an inner tube, which enhances the strength of the inner tube. The threaded connection between the outer tube and the inner tube makes it easy to disassemble and maintain. After the inner tube abuts against the positioning ring on the outer tube, it is tightened with bolts to ensure the firmness of the assembly. After the double-wall drill rod is assembled, the inner tube abuts against the positioning ring to prevent the bolts from loosening. The sealing gasket on the positioning ring ensures the sealing of the assembly.

[0021] 2. The inner tube is assembled with the outer tube through the alignment ring. The internal thread on the alignment ring allows it to move smoothly along the outer tube. After contacting the external thread on the outer tube, the outer sleeve is screwed to connect the alignment ring and the outer tube. After the alignment ring is assembled in place, the elastic retaining ring is inserted into the connecting groove on the outer tube and abuts against the end face of the alignment ring. This restrains and restricts the alignment ring, ensuring the firmness of the outer sleeve assembly with the outer tube.

[0022] 3. When performing air lift reverse circulation drilling, the air compressor is connected to the double-wall drill pipe through pipelines. After the drilling fluid and compressed air are mixed, they are transported to the passage between the outer casing and the outer casing, as well as to the downhole along the flow holes on the alignment ring. The air compressor carries rock cuttings into the inner casing and transports the rock cuttings upward to the external sedimentation tank. The operation is smooth and reliable. Attached Figure Description

[0023] Figure 1 This is a schematic diagram of the structure of the air-lift reverse circulation double-wall drill string in this embodiment;

[0024] Figure 2 This is a cross-sectional structural diagram of the air-lift reverse circulation double-wall drill string in this embodiment;

[0025] Figure 3 This is a schematic diagram of the disassembled structure of the outer tube and the elastic retaining ring in this embodiment;

[0026] Figure 4 This is a schematic diagram of the inner tube structure in this embodiment;

[0027] Figure 5 This is a schematic diagram of the disassembled structure of the outer sleeve and inner sleeve in this embodiment;

[0028] Figure 6 This is a schematic diagram showing the disassembled structure of the positioning ring and sealing gasket in this embodiment.

[0029] In the diagram, 1 is the outer tube; 101 is the connecting groove; 102 is the elastic retaining ring; 103 is the external thread; 2 is the inner tube; 201 is the inner sleeve; 202 is the outer sleeve; 3 is the alignment ring; 301 is the flow hole; 302 is the internal thread; 4 is the positioning ring; 5 is the bolt; and 6 is the sealing gasket. Detailed Implementation

[0030] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments.

[0031] Please see the appendix Figure 1 Appendix Figure 5 Appendix Figure 6 The air-lift reverse circulation double-wall drill bit used in conjunction with an air compressor includes an outer tube 1 and an inner tube 2 arranged coaxially. The inner tube 2 includes an outer sleeve 202 and an inner sleeve 201 that are coaxially and detachably sleeved. The outer sleeve 202 and the inner sleeve 201 can be connected by threads. A positioning ring 4 is provided on the inner tube 2 wall of the outer sleeve 202. After the inner sleeve 201 abuts against the positioning ring 4, the inner sleeve 201 and the outer sleeve 202 are assembled in place. Bolts 5 are threaded along the circumferential direction on the positioning ring 4. All bolts 5 are threaded to the inner sleeve 201, thereby locking the outer sleeve 202 and the inner sleeve 201. The top surface of the bolts 5 is flush with the top surface of the positioning ring 4. Sealing gaskets 6 are provided on the top and bottom surfaces of the positioning ring 4. The sealing gasket 6 on the bottom surface ensures the sealing of the connection between the inner sleeve 201 and the positioning ring 4 and the outer sleeve 202.

[0032] Please see the appendix Figure 2 Appendix Figure 4 Multiple alignment rings 3 are evenly arranged along the height direction on the outer tube 1 wall of the outer tube 202. The alignment ring 3 is fixed by welding the inner ring wall to the outer tube 1 wall of the outer tube 202. After the outer tube 202 is placed inside the outer tube 1 of the double-wall drill pipe, it is threaded to the outer tube 1. The inner tube 2 wall of the outer tube 1 is provided with an external thread 103, and the alignment ring 3 is provided with an internal thread 302. This allows the alignment ring 3 to move smoothly along the inner wall of the outer tube 1, avoiding interference with the assembly of the outer tube 1. After the internal thread 302 on the alignment ring 3 engages with the external thread 103 on the outer tube 202, the alignment ring 3 is assembled into place and provides positional support for the outer tube 202.

[0033] Please see the appendix Figure 3The inner tube 2 of the outer tube 1 is provided with connecting grooves 101 at both the upper and lower parts of the wall. After the alignment ring 3 and the outer tube 202 are assembled, the elastic retaining rings 102 are respectively inserted into the connecting grooves 101, and the elastic retaining rings 102 respectively abut against the end face of the alignment ring 3 on the outer tube 202, thereby constraining the alignment ring 3 inside the outer tube 1 to ensure the reliability of the inner tube 2. The alignment ring 3 is provided with flow holes 301 evenly arranged along the circumference. The flow holes 301 allow drilling fluid to flow along the passage between the outer tube 1 and the outer tube 202.

[0034] The working principle of this air-lift reverse circulation double-wall drill bit used with an air compressor is as follows: When assembling the double-wall drill pipe and performing air-lift reverse circulation drilling operations with an air compressor, the outer sleeve 202 and the inner sleeve 201 are threaded together, and the top surface of the inner sleeve 201 abuts against the positioning ring 4 on the outer sleeve 202 to assemble it into place. The positioning ring 4 and the inner sleeve 201 are then tightened and fixed with bolts 5 to ensure the firmness of the assembly of the outer sleeve 202 and the inner sleeve 201. Sealing gaskets 6 are provided on the top and bottom surfaces of the positioning ring 4 to ensure the sealing of the assembly of the outer sleeve 202 and the inner sleeve 201. Then, the outer sleeve 202 is pushed into the outer tube 1. The alignment ring 3 on the outer sleeve 202 slides along the inner tube 2 wall of the outer tube 1, coaxially supporting the outer sleeve 202 and the inner sleeve 201 on the outer tube 1. After the alignment ring 3 contacts the external thread 103 on the outer tube 1, the outer sleeve 202 is screwed to connect the alignment ring 3 to the threaded assembly of the outer tube 1. After the alignment ring 3 is assembled in place, the elastic retaining ring 102 is inserted into the connecting groove 101 on the outer tube 1 and abuts against the end face of the alignment ring 3, thereby constraining and restricting the alignment ring 3 and ensuring the firmness of the outer sleeve 202 in the outer tube 1 assembly. After the outer sleeve 202 and the outer tube 1 are assembled into a double-wall drill rod, the outer tubes 1 are tightened together during the assembly of the double-wall drill rod. The inner sleeve 201 on the inner tube 2 is inserted into the outer sleeve 202 on the other double-wall drill rod. The protrusion height of the top surface of the outer sleeve 202 is not greater than the protrusion height of the bottom surface of the inner sleeve 201, so that the inner sleeve 201 and the outer sleeve 202 are reliably inserted. The inner sleeve 201 and the sealing gasket 6 on the positioning ring 4 of the outer sleeve 202 abut against each other to ensure the sealing of the insertion. The top surface of the bolt 5 is flush with the top surface of the positioning ring 4 to ensure the sealing effect of the sealing gasket 6. During gas lift reverse circulation drilling, the air compressor is connected to the double-walled drill pipe through pipelines. The drilling fluid and compressed air are mixed and transported to the passage between the outer casing 1 and the outer casing 202, and flow along the flow hole 301 on the alignment ring 3 to the downhole. The air compressor also carries rock cuttings into the inner casing 201 and transports the rock cuttings upward to the external sedimentation tank for gas lift reverse circulation drilling operations.

Claims

1. An air-lift reverse circulation double-wall drill bit for use with an air compressor, comprising an outer tube (1) and an inner tube (2) coaxially arranged, characterized in that: The inner tube (2) includes an inner sleeve (201) and an outer sleeve (202) that are coaxially fixedly sleeved together. The bottom surface of the inner sleeve (201) protrudes from the bottom surface of the outer sleeve (202), and the top surface of the outer sleeve (202) protrudes from the top surface of the inner sleeve (201). The protrusion height of the top surface of the outer sleeve (202) is not greater than the protrusion height of the bottom surface of the inner sleeve (201). Alignment rings (3) are uniformly arranged along the height direction on the outer sleeve (202). The alignment rings (3) are threadedly connected to the inner tube (2) wall of the outer tube (1). Flow holes (301) are provided along the circumferential direction on the alignment rings (3).

2. The air-lift reverse circulation double-walled drill bit for use with an air compressor as described in claim 1, characterized in that: The outer sleeve (202) is threadedly connected to the inner sleeve (201), and a positioning ring (4) is provided on the inner tube (2) wall of the outer sleeve (202). The top surface of the inner sleeve (201) abuts against the positioning ring (4), and the positioning ring (4) is locked to the inner sleeve (201) by means of a locking member.

3. The air-lift reverse circulation double-walled drill bit for use with an air compressor as described in claim 2, characterized in that: The locking element includes a bolt (5) threaded onto the positioning ring (4), and the bolt (5) is threaded onto the inner sleeve (201).

4. The air-lift reverse circulation double-walled drill bit for use with an air compressor according to claim 3, characterized in that: The top surface of the bolt (5) is flush with the top surface of the positioning ring (4), and sealing gaskets (6) are provided on both the upper and lower end faces of the positioning ring (4).

5. The air-lift reverse circulation double-walled drill bit for use with an air compressor as described in claim 1, characterized in that: The inner ring wall of the positive ring (3) is welded and fixed to the outer tube (1) wall of the outer sleeve (202).

6. The air-lift reverse circulation double-walled drill bit for use with an air compressor as described in claim 1, characterized in that: The inner tube (2) wall of the outer tube (1) is provided with connecting grooves (101) at both the upper and lower parts, and elastic retaining rings (102) are provided in the connecting grooves (101). The elastic retaining rings (102) abut against the end face of the alignment ring (3).

7. The air-lift reverse circulation double-walled drill bit for use with an air compressor according to claim 6, characterized in that: The inner tube (2) wall of the outer sleeve (202) is provided with external threads (103) corresponding to the position and number of the alignment rings (3) along the height direction, and the alignment rings (3) are provided with internal threads (302) that match the external threads (103).

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