Filter joint and reverse circulation drilling machine

Abstract

The invention discloses a filter joint and a reverse circulation drilling machine. The filter joint comprises a slag discharge pipe, an outer sleeve and a gas-slag separation mechanism, wherein a slag discharging channel is arranged in the slag discharging pipe, the outer sleeve is arranged on the outer side of the slag discharging pipe in a sleeving mode, a high-pressure gas channel is formed between the outer sleeve and the slag discharging pipe, the two ends of the gas-slag separation mechanism are communicated with the high-pressure gas channel, and the gas-slag separation mechanism is used for separating impurities in high-pressure gas; the gas-slag separation mechanism comprises a first channel and a second channel which are mutually spaced, the first channel and the second channel are communicated through a third channel, the front end of the first channel and the rear end of the second channel are communicated with the high-pressure air channel, and the rear end of the first channel and the front end of the second channel are isolated from the high-pressure air channel. Compared with the prior art, the filter connector and the reverse circulation drilling machine can filter impurities in high-pressure gas, and the problem that the impurities enter a reverse circulation impactor to cause blockage of a piston is solved.

Description

Technical Field

[0001] The present application relates to the technical field of drilling equipment, and more specifically, to a filter joint and a reverse circulation drilling rig. Background Art

[0002] With the development of industry, various infrastructure projects are constantly advancing. As drilling equipment, down-the-hole impactors are widely used in infrastructure, water wells, mines, hydropower stations, ports, roads, tunnels and other engineering construction projects for drilling pile foundation holes and blasting holes. The down-the-hole impactor uses a compressor to provide high-pressure water or compressed air into the impactor, driving the piston inside the impactor to reciprocate at high speed. The reciprocating motion of the piston hits the drill bit again and again, and the alloy teeth at the front end of the drill bit are used to break the rock. The rock slag generated in the rock breaking process is discharged through the slag discharge channel of the impactor by high-pressure water or high-pressure gas.

[0003] There are two types of impactors on the market. One is a down-the-hole positive circulation impactor. The drill pipe is a single-layer tube. High-pressure gas is blown into the inside of the impactor through the drill pipe, causing the piston to move up and down to do work. The high-pressure gas after doing work flows into the bottom of the drilled hole through the air flow channel in the inner hole of the drill bit. The high-pressure gas at the bottom of the hole blows the rock debris to the outside of the drill bit, and then blows it into the gap between the outer wall of the impactor and the wall of the drilled hole, and finally discharges it from the drilled hole mouth; the other is a down-the-hole reverse circulation impactor. The drill pipe is a double-layer tube. High-pressure gas is blown into the inside of the impactor through the outer tube of the drill pipe, causing the piston to move up and down to do work. The high-pressure gas after doing work is blown into the bottom of the drilled hole through the air flow channel on the shank of the drill bit. The high-pressure gas at the bottom of the hole blows the rock debris into the rock debris collection hole inside the drill bit, and then blows it into the collection tube, and then blows the rock debris into the inner tube of the drill pipe through the collection tube, and finally collects the rock debris through the dust collection device of the drilling rig. This type of reverse circulation impactor is environmentally friendly and can collect and analyze rock debris, and is widely used.

[0004] At present, during the drilling process of the reverse circulation impactor, the outer tube of the drill pipe is connected to the air compressor, and high-pressure gas is blown into the space between the outer tube and the inner tube through the air compressor. However, due to the aging of the air duct of the air compressor, the rubber on the inner wall of the air duct is easy to fall off and enter the reverse circulation impactor along with the high-pressure gas, thereby causing the piston of the reverse circulation impactor to be stuck and unable to work normally.

[0005] Therefore, there is an urgent need for a filter joint and a reverse circulation drilling rig that can filter impurities in high-pressure gas to prevent the impurities from entering the interior of the reverse circulation impactor and causing the piston to become stuck. Summary of the invention

[0006] In order to solve the above technical problems, the present application provides a filter joint and a reverse circulation drilling rig, which can filter impurities in high-pressure gas to prevent impurities from entering the interior of the reverse circulation impactor and causing the piston to get stuck.

[0007] The technical solutions provided by this application are as follows: A filter joint comprises a slag discharge pipe, an outer sleeve and a gas-slag separation mechanism; in, The slag discharge pipe is provided with a slag discharge channel, the outer sleeve is sleeved on the outside of the slag discharge pipe, a high-pressure gas channel is formed between the outer sleeve and the slag discharge pipe, both ends of the gas-slag separation mechanism are connected to the high-pressure gas channel, and the gas-slag separation mechanism is used to separate impurities in the high-pressure gas; The gas-slag separation mechanism includes a first channel and a second channel spaced apart from each other, the first channel and the second channel are connected via a third channel, the front end of the first channel and the rear end of the second channel are connected to the high-pressure air channel, and the rear end of the first channel and the front end of the second channel are isolated from the high-pressure air channel.

[0008] Preferably, at least two first channels are provided, and the total area of ​​the inlet of the first channels communicating with the high-pressure air channel is less than or equal to the sum of the areas of the air inlet of the third channel communicating with the second channel.

[0009] Preferably, the slag discharge pipe is provided with a body, both ends of the slag discharge pipe are provided with a first baffle and a second baffle, and the body is provided with first grooves and second grooves alternately spaced in the circumferential direction; The first groove passes through the first baffle plate and is connected to the high-pressure airway, the second groove passes through the second baffle plate and is connected to the high-pressure airway, the first groove, the outer sleeve, the first baffle plate and the second baffle plate form the first channel, and the second groove, the outer sleeve, the first baffle plate and the second baffle plate form the second channel.

[0010] Preferably, the first groove and the second groove extend along the axial direction of the body; At least two third channels are provided between adjacent first grooves and second grooves, and the third channels are arranged at intervals along the axial direction of the body.

[0011] Preferably, the third channel is specifically an annular groove, and the third channel extends around the circumference of the body.

[0012] Preferably, it also includes: A positioning stopper disposed on the outer surface of the slag discharge pipe; A positioning step is provided on the inner wall of the outer sleeve, wherein the front end surface of the positioning step is used to abut against the rear end surface of the positioning stopper; A retaining spring is fixedly arranged on the inner wall of the outer sleeve, and the retaining spring is used to abut against the front end surface of the positioning stopper, and an air passage groove is formed between the positioning stopper, the retaining spring and the inner wall of the outer sleeve.

[0013] Preferably, the air passage grooves and the inlet are alternately arranged in the circumferential direction of the slag discharge pipe.

[0014] Preferably, a tapered internal thread is provided on the inner wall of the front end of the outer sleeve, and the inner diameter of the tapered internal thread gradually decreases from the front end to the rear end of the outer sleeve, and a first sealing member is provided on the outer surface of the front end of the slag discharge pipe; A tapered external thread is provided on the outer wall of the rear end of the outer sleeve, and the outer diameter of the tapered external thread gradually decreases from the front end to the rear end of the outer sleeve. A second sealing member is provided on the inner surface of the rear end of the slag discharge pipe, and a positioning surface is provided on the inner wall of the rear end of the slag discharge pipe.

[0015] Preferably, the first sealing member and the second sealing member are both strip-shaped sealing rings, the strip-shaped sealing rings extend along the axial direction of the slag discharge pipe, and the strip-shaped sealing rings are provided with a rough surface in a direction away from the slag discharge pipe.

[0016] A reverse circulation drilling rig, comprising a drill pipe, a reverse circulation impactor connected to the drill pipe, and any one of the filter joints described above; in, The filter joint of the reverse circulation impactor is arranged between adjacent drill pipes; or, The filter joint of the reverse circulation impactor is arranged between the drill pipe and the reverse circulation impactor.

[0017] The filter joint provided by the present invention is firstly provided with a slag discharge pipe, an outer sleeve and a gas-slag separation mechanism, wherein a slag discharge channel is provided in the slag discharge pipe, the slag discharge channel is used to be connected with the inner tube of the drill pipe, and is used to discharge the residue generated during the drilling process of the down-the-hole impactor, the outer sleeve is used to be connected with the outer tube of the drill pipe, a high-pressure airway is formed between the outer sleeve and the slag discharge pipe, both ends of the gas-slag separation mechanism are connected with the high-pressure airway, and the gas-slag separation mechanism is used to separate impurities in the high-pressure gas to prevent the impurities from entering the down-the-hole impactor. Secondly, the gas-slag separation mechanism includes a first channel, a second channel and a third channel, wherein the first channel and the second channel are spaced apart from each other, the front end of the first channel and the rear end of the second channel are connected to the high-pressure gas channel, the rear end of the first channel and the front end of the second channel are isolated from the high-pressure gas channel, the first channel and the second channel are connected through the third channel, the high-pressure gas output by the air compressor enters the high-pressure gas channel between the slag discharge pipe and the outer sleeve, a part of the mixture of high-pressure gas and impurities enters the first channel through the front end of the first channel, the impurities are transmitted to the rear end along the direction of the first channel to block the slag, and the high-pressure gas enters the second channel through the third channel and enters the high-pressure gas channel through the rear end of the second channel; another part of the mixture of high-pressure gas and impurities hits the front end of the second channel, the impurities are blocked by the front end of the second channel, and the high-pressure gas can enter the first channel through the front end of the first channel. Due to the provision of the first channel, the second channel and the third channel, the high-pressure gas and impurities are separated through the third channel, thereby preventing the impurities from entering the interior of the reverse circulation impactor. It can be seen that, compared with the prior art, the filter joint in the embodiment of the present invention can filter impurities in the high-pressure gas, thereby preventing the impurities from entering the interior of the reverse circulation impactor and causing the piston to become stuck.

[0018] The present application also provides a reverse circulation drilling rig, including a drill pipe, a reverse circulation impactor, and the above-mentioned filter joint, wherein the reverse circulation impactor is connected to the drill pipe, wherein the filter joint is arranged between two adjacent drill pipes, or the filter structure is arranged between the drill pipe and the reverse circulation impactor. Since the reverse circulation drilling rig provided by the present application is provided with a filter joint, it is also possible to filter impurities in the high-pressure gas, thereby preventing the impurities from entering the interior of the reverse circulation impactor and causing the piston to become stuck. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1A schematic diagram of the structure of a filter joint provided in an embodiment of the present invention; Figure 2 A cross-sectional view of a filter joint provided in an embodiment of the present invention; Figure 3 A working principle diagram of a filter joint provided by an embodiment of the present invention; Figure 4 A schematic diagram of the structure of an outer sleeve provided in an embodiment of the present invention; Figure 5 A schematic diagram of the structure of a slag discharge pipe provided in an embodiment of the present invention; Figure 6 A schematic diagram of the structure of the main body provided by an embodiment of the present invention; Figure 7 A schematic diagram of the structure of a retaining spring provided in an embodiment of the present invention; Figure 8 A schematic structural diagram of a first sealing member provided in an embodiment of the present invention; Fig. 9 A schematic diagram of the chair red structure of the second sealing member provided in an embodiment of the present invention.

[0021] Figure numerals: 1. slag discharge pipe; 2. outer sleeve; 3. high-pressure air channel; 4. third channel; 51. main body; 52. first baffle; 53. second baffle; 54. first groove; 55. second groove; 61. positioning block; 62. positioning step; 63. retaining spring; 64. air groove; 21. tapered internal thread; 22. tapered external thread; 11. slag discharge channel; 12. first sealing member; 13. second sealing member; 14. positioning surface. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to 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 described embodiments are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0023] 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.

[0024] 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 drawings, and are only for the convenience of describing the present 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 should not be understood as a limitation on the present application.

[0025] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, "multiple" and "several" mean two or more, unless otherwise clearly and specifically defined.

[0026] 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 effects and purposes that can be achieved by this application.

[0027] The embodiments of the present invention are written in a progressive manner.

[0028] like Figures 1 to 9 As shown, an embodiment of the present invention provides a filter joint, including a slag discharge pipe 1, an outer sleeve 2 and a gas-slag separation mechanism; wherein, a slag discharge channel 11 is provided in the slag discharge pipe 1, the outer sleeve 2 is mounted on the outside of the slag discharge pipe 1, a high-pressure airway 3 is formed between the outer sleeve 2 and the slag discharge pipe 1, both ends of the gas-slag separation mechanism are connected to the high-pressure airway 3, and the gas-slag separation mechanism is used to separate impurities in the high-pressure gas; the gas-slag separation mechanism includes a first channel and a second channel spaced apart from each other, the first channel and the second channel are connected through a third channel 4, the front end of the first channel and the rear end of the second channel are connected to the high-pressure airway 3, and the rear end of the first channel and the front end of the second channel are isolated from the high-pressure airway 3.

[0029] At present, during the drilling process of the reverse circulation impactor, the outer tube of the drill pipe is connected to the air compressor, and high-pressure gas is blown into the space between the outer tube and the inner tube through the air compressor. However, due to the aging of the air duct of the air compressor, the rubber on the inner wall of the air duct is easy to fall off and enter the reverse circulation impactor along with the high-pressure gas, thereby causing the piston of the reverse circulation impactor to be stuck and unable to work normally.

[0030] It should be noted that the front end and the rear end in the present application refer to the distinction along the flow direction of the high-pressure gas, and the high-pressure gas flows from the front end to the rear end in the high-pressure gas channel 3.

[0031] The filter joint provided by the present invention is firstly provided with a slag discharge pipe 1, an outer sleeve 2 and a gas-slag separation mechanism, wherein a slag discharge channel 11 is provided in the slag discharge pipe 1, and the slag discharge channel 11 is used to be connected with the inner pipe of the drill pipe, and is used to discharge the residue generated during the drilling process of the down-the-hole impactor. The outer sleeve 2 is used to be connected with the outer pipe of the drill pipe, and a high-pressure airway 3 is formed between the outer sleeve 2 and the slag discharge pipe 1. Both ends of the gas-slag separation mechanism are connected with the high-pressure airway 3. The gas-slag separation mechanism is used to separate impurities in the high-pressure gas to prevent the impurities from entering the down-the-hole impactor. Secondly, the gas-slag separation mechanism includes a first channel, a second channel and a third channel 4, wherein the first channel and the second channel are arranged at intervals from each other, the front end of the first channel and the rear end of the second channel are connected to the high-pressure gas channel 3, the rear end of the first channel and the front end of the second channel are isolated from the high-pressure gas channel 3, the first channel and the second channel are connected through the third channel 4, the high-pressure gas output by the air compressor enters the high-pressure gas channel 3 between the slag discharge pipe 1 and the outer sleeve 2, a part of the high-pressure gas and impurity mixture enters the first channel through the front end of the first channel, the impurities are transmitted to the rear end along the direction of the first channel to block the slag, and the high-pressure gas enters the second channel through the third channel 4, and enters the high-pressure gas channel 3 through the rear end of the second channel; another part of the high-pressure gas and impurity mixture hits the front end of the second channel, the impurities are blocked by the front end of the second channel, and the high-pressure gas can enter the first channel through the front end of the first channel. Due to the provision of the first channel, the second channel and the third channel 4, the high-pressure gas and impurities are separated through the third channel 4, thereby preventing the impurities from entering the interior of the reverse circulation impactor. It can be seen that, compared with the prior art, the filter joint in the embodiment of the present invention can filter impurities in the high-pressure gas, thereby preventing the impurities from entering the interior of the reverse circulation impactor and causing the piston to become stuck.

[0032] In the present application, slag blocking for impurities in high-pressure gas is mainly divided into three aspects. First, when a part of the diverted high-pressure gas and impurity mixture enters the first channel and flows in the first channel, the high-pressure gas can enter the second channel through the third channel 4 and enter the rear end of the high-pressure gas channel 3 along the second channel, but most of the impurities will flow to the rear end of the first channel and block slag through the rear end of the first channel. Second, when the impurities in the first channel enter the second channel through the third channel 4, slag is blocked through the opening of the third channel 4 to prevent the impurities from entering the second channel through the third channel 4; third, when another part of the diverted high-pressure gas and impurity mixture hits the second channel at the front end of the high-pressure gas, slag is blocked through the front end surface of the second channel, and the high-pressure gas can enter the front end of the first channel. In this way, by setting up a gas-slag separation mechanism, the impurities are separated from the high-pressure gas through the gas-slag separation mechanism to prevent the impurities from entering the reverse circulation impactor.

[0033] In the above structure, the number of first channels is determined according to the amount of high-pressure gas. Specifically, in the embodiment of the present invention, at least two first channels are provided. The third channel 4 is used to connect the first channel and the second channel. At least two third channels 4 are provided between the first channel and the second channel in an adjacent group, and the third channels 4 are spaced apart along the direction in which the first channel extends.

[0034] Since the high-pressure gas enters the first channel from the high-pressure air channel 3 through the inlet, in order to avoid excessive loss of high-pressure gas in the first channel, as one implementation method, the total area of ​​the inlet in the embodiment of the present invention is smaller than the sum of the cross-sectional areas of the air inlets of the third channel 4.

[0035] It should be noted that the inlet here specifically refers to the opening where the first channel is connected to the high-pressure air channel 3, and the air inlet of the third channel 4 here refers to the opening where the third channel 4 is connected to the first channel.

[0036] In the above structure, the first channel in the embodiment of the present invention can be arranged in the outer sleeve 2, or the first channel is arranged in the inner sleeve, or the first channel is specifically formed by the outer sleeve 2 and the inner sleeve.

[0037] The second channel in the embodiment of the present invention can be arranged in the outer sleeve 2, or the second channel is arranged in the inner sleeve, or the second channel is formed by the inner sleeve and the outer sleeve 2.

[0038] The present application does not limit the specific positions of the first channel and the second channel. The first channel and the second channel are mainly spaced apart and connected to each other through the third channel 4 to block slag.

[0039] In the above structure, as a first specific embodiment, a main body 51 is provided on the slag discharge pipe 1 in the embodiment of the present invention, and a first baffle 52 and a second baffle 53 are provided at both ends of the main body 51, and a first groove 54 and a second groove 55 are alternately provided circumferentially on the main body 51. The first groove 54 passes through the first baffle 52 to communicate with the high-pressure air duct 3, and the rear end of the second groove 55 passes through the second baffle 53 to communicate with the high-pressure air duct 3. A first channel is formed between the first groove 54, the outer sleeve 2, and the first baffle 52 and the second baffle 53, and a second channel is formed between the second groove 55, the outer sleeve 2, the first baffle 52 and the second baffle 53.

[0040] Furthermore, in order to facilitate the cleaning of impurities, as one of the implementation modes, the main body 51 in the embodiment of the present invention and the outer sleeve 2 are specifically clearance-matched. In order to prevent impurities from directly entering the rear end of the high-pressure airway 3 through the gap between the main body 51 and the outer sleeve 2, the gap between the first baffle 52 and the outer sleeve 2 in the embodiment of the present invention is 0.1 mm to 0.2 mm, and the gap between the main body 51 and the outer sleeve 2 in the embodiment of the present invention is 0.5 mm to 1 mm.

[0041] Furthermore, the main body 51 and the slag discharge pipe 1 in the embodiment of the present invention may be detachably connected, or the main body 51 and the slag discharge pipe 1 in the embodiment of the present invention may be an integrally formed structure.

[0042] Furthermore, as one of the implementations, the structure and arrangement of the third channel 4 can be selected based on actual use and processing needs. The third channel 4 here mainly changes the flow direction of the high-pressure gas so that the high-pressure gas in the first channel flows into the second channel, thereby preventing impurities from entering the second channel. More specifically, the third channel 4 in the embodiment of the present invention can be a straight line, an arc shape or a U-shaped structure.

[0043] In the above structure, the direction in which the first groove 54 extends can be a curve, a spiral, a folded line or a straight line. In order to avoid the situation where the first channel is blocked by the accumulation of impurities, the first channel in the embodiment of the present invention is preferably a straight line. The direction in which the second groove 55 extends can be a curve, a spiral, a straight line or a folded line. The first groove 54 and the second groove 55 in the embodiment provided by the embodiment of the present invention specifically extend along a straight line.

[0044] In one embodiment, the first groove 54 and the second groove 55 in the embodiment of the present invention extend along the axial direction of the body 51, at least two third channels 4 are provided between the same first groove 54 and the second groove 55, and the third channels 4 are arranged at intervals along the axial direction of the body 51.

[0045] Furthermore, as one specific implementation manner, the third channel 4 in the embodiment of the present invention is specifically an annular groove, and the third channel 4 is arranged around the circumference of the body 51.

[0046] As a second embodiment, the main body 51 in the embodiment of the present invention can also be fixedly set in the outer sleeve 2, and the first groove 54 and the second groove 55 are set on the inner surface of the main body 51. The other structures are the same as the first embodiment, and the above-mentioned technical effects can also be achieved, which will not be further elaborated here.

[0047] In the above structure, in order to facilitate the disassembly of the outer sleeve 2 and the slag discharge pipe 1, as one of the implementation modes, the filtering structure in the embodiment of the present invention also includes a positioning block 61, a positioning step 62 and a retaining spring 63, wherein the positioning block 61 is arranged on the outer surface of the slag discharge pipe 1, the positioning step 62 is arranged on the inner wall of the outer sleeve 2, the front end face of the positioning step 62 is used to abut with the rear end face of the positioning block 61, the retaining spring 63 is arranged on the inner wall of the outer sleeve 2, the retaining spring 63 is detachably fixedly connected to the outer sleeve 2, the retaining spring 63 is used to abut with the front end face of the positioning block 61 to fix the slag discharge pipe 1, and in order to facilitate the circulation of high-pressure gas, an air groove 64 is formed between the positioning block 61, the retaining spring 63 and the inner wall of the outer sleeve 2.

[0048] More specifically, if Figure 7 As shown, the retaining spring 63 is detachably installed in the outer sleeve 2. A retaining spring groove is provided on the inner wall of the outer sleeve 2. The retaining spring 63 is specifically a ring structure with an opening. Under the action of external force, the circumferential surface of the retaining spring 63 is placed in the retaining spring groove, and the end face of the retaining spring 63 abuts against the front end face of the positioning block 61 for positioning.

[0049] Furthermore, as one embodiment, the gas passage grooves 64 and the inlet are staggeredly arranged in the circumferential direction of the slag discharge pipe 1. That is, after the mixture of high-pressure gas and impurities passes through the gas passage grooves 64, the first baffle 52 blocks part of the impurities.

[0050] Furthermore, as one implementation mode, the positioning stopper 61 in the embodiment of the present invention is specifically a three-way positioning joint arranged on the outside of the slag discharge pipe 1 .

[0051] Furthermore, the positioning stopper 61 and the slag discharge pipe 1 in the embodiment of the present invention are specifically an integrally formed structure.

[0052] Furthermore, as one implementation method, Figure 8 and Fig. 9As shown, a tapered internal thread 21 is provided on the inner wall of the front end of the outer sleeve 2 in the embodiment of the present invention, and the inner diameter of the tapered internal thread 21 gradually decreases from the front end to the rear end of the outer sleeve 2, and a first sealing member 12 is provided on the outer surface of the front end of the slag discharge pipe 1; a tapered external thread 22 is provided on the outer wall of the rear end of the outer sleeve 2, and the outer diameter of the tapered external thread 22 gradually decreases from the front end to the rear end of the outer sleeve 2, a second sealing member 13 is provided on the inner surface of the rear end of the slag discharge pipe 1, and a positioning surface 14 is provided on the inner wall of the rear end of the slag discharge pipe 1.

[0053] like Figure 8 As shown, further, as one implementation mode, at least two first sealing members 12 are provided in the embodiment of the present invention, and the first sealing members 12 are arranged at intervals along the axial direction of the slag discharge pipe 1 .

[0054] Specifically, the front end of the outer sleeve 2 is fixedly connected to the outer tube of the drill pipe through a tapered internal thread 21, the slag discharge pipe 1 is sealed to the inner tube of the drill pipe through a first seal 12, the rear end of the outer sleeve 2 is fixedly connected to the outer tube of the drill pipe or the joint of the reverse circulation impactor through a tapered external thread 22, and the slag discharge pipe 1 is sealed to the inner tube of the drill pipe or the collection pipe of the reverse circulation impactor through a second seal 13.

[0055] Furthermore, the first seal 12 and the second seal 13 can be sealing rings or sealing rings. As a preferred embodiment, the first seal 12 and the second seal 13 are preferably strip-shaped sealing rings, which extend along the axial direction of the slag discharge pipe 1, and the strip-shaped sealing ring is set to a rough surface in the direction away from the slag discharge pipe 1.

[0056] Conventional O-rings have poor sealing performance, and the strip-shaped sealing ring has a larger contact area for sealing, and a rough surface is provided on the strip-shaped sealing ring, so that the sealing effect is better.

[0057] In the above structure, as one of the implementation modes, a first sealing groove for use with a first sealing member 12 is provided on the slag discharge pipe 1 in the embodiment of the present invention. Both sides of the length of the first sealing groove are inclined surfaces, and the length of the first sealing groove gradually decreases in the direction away from the bottom of the first sealing groove. In this way, the installation of the first sealing member 12 can be more convenient.

[0058] Furthermore, a second sealing groove is provided on the inner wall of the outer sleeve 2, and the second sealing groove is used in conjunction with the second sealing member 13. Both sides of the length of the second sealing groove are inclined surfaces, and the length of the second sealing groove gradually decreases in the direction away from the bottom of the second sealing groove. In this way, the installation of the second sealing member 13 can be more convenient.

[0059] The present application also provides a reverse circulation drilling rig, comprising a drill rod, a reverse circulation impactor connected to the drill rod, and any one of the above filter joints; wherein the filter joint of the reverse circulation impactor is arranged between adjacent drill rods; or, the filter joint of the reverse circulation impactor is arranged between the drill rod and the reverse circulation impactor. Due to the provision of the filter joint, impurities in the high-pressure gas can also be filtered, so as to prevent the impurities from entering the interior of the reverse circulation impactor and causing the piston to be stuck.

[0060] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be 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 will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A filter connector, characterized in that: It comprises a slag discharge pipe (1), an outer sleeve (2) and a gas-slag separation mechanism; in, The slag discharge pipe (1) is provided with a slag discharge passage (11), an outer sleeve (2) is sleeved on the outside of the slag discharge pipe (1), a high-pressure gas passage (3) is formed between the outer sleeve (2) and the slag discharge pipe (1), two ends of the gas-slag separation mechanism are connected to the high-pressure gas passage (3), and the gas-slag separation mechanism is used to separate impurities in the high-pressure gas; The gas-slag separation mechanism comprises a first channel and a second channel which are spaced apart from each other, the first channel and the second channel being connected via a third channel (4), the front end of the first channel and the rear end of the second channel being connected to a high-pressure gas channel (3), and the rear end of the first channel and the front end of the second channel being isolated from the high-pressure gas channel (3).

2. The filter connector according to claim 1, characterized in that: At least two first channels are provided, and the total area of ​​the inlet of the first channels communicating with the high-pressure air channel (3) is less than or equal to the sum of the areas of the air inlet of the third channel (4) communicating with the second channel.

3. The filter connector according to claim 1, characterized in that: The slag discharge pipe (1) is provided with a body (51), two ends of the slag discharge pipe (1) are provided with a first baffle (52) and a second baffle (53), and the body (51) is provided with first grooves (54) and second grooves (55) alternately arranged in a circumferential direction; The first groove (54) passes through the first baffle plate (52) and is in communication with the high-pressure air passage (3); the second groove (55) passes through the second baffle plate (53) and is in communication with the high-pressure air passage (3); the first groove (54), the outer sleeve (2), the first baffle plate (52) and the second baffle plate (53) form the first channel; the second groove (55), the outer sleeve (2), the first baffle plate (52) and the second baffle plate (53) form the second channel.

4. The filter connector according to claim 3, characterized in that: The first groove (54) and the second groove (55) extend along the axial direction of the body (51); At least two third channels (4) are provided between adjacent first grooves (54) and second grooves (55), and the third channels (4) are arranged at intervals along the axial direction of the body (51).

5. The filter connector according to claim 4, characterized in that: The third channel (4) is specifically an annular groove, and the third channel (4) extends around the circumference of the body (51).

6. The filter connector according to claim 2, characterized in that: Also includes: A positioning stopper (61) provided on the outer surface of the slag discharge pipe (1); A positioning step (62) is provided on the inner wall of the outer sleeve (2), wherein the front end surface of the positioning step (62) is used to abut against the rear end surface of the positioning stopper (61); A retaining spring (63) is fixedly arranged on the inner wall of the outer sleeve (2), the retaining spring (63) being used to abut against the front end surface of the positioning block (61), and an air passage groove (64) is formed between the positioning block (61), the retaining spring (63) and the inner wall of the outer sleeve (2).

7. The filter connector according to claim 6, characterized in that: The air passage grooves (64) and the inlet are arranged alternately in the circumferential direction of the slag discharge pipe (1).

8. The filter connector according to claim 1, characterized in that: A tapered internal thread (21) is provided on the inner wall of the front end of the outer sleeve (2), and the inner diameter of the tapered internal thread (21) gradually decreases from the front end to the rear end of the outer sleeve (2). A first sealing member (12) is provided on the outer surface of the front end of the slag discharge pipe (1); A tapered external thread (22) is provided on the outer wall of the rear end of the outer sleeve (2), and the outer diameter of the tapered external thread (22) gradually decreases from the front end to the rear end of the outer sleeve (2). A second sealing member (13) is provided on the inner surface of the rear end of the slag discharge pipe (1), and a positioning surface (14) is provided on the inner wall of the rear end of the slag discharge pipe (1).

9. The filter connector according to claim 8, characterized in that: The first sealing member (12) and the second sealing member (13) are both strip-shaped sealing rings, the strip-shaped sealing rings extending along the axial direction of the slag discharge pipe (1), and the strip-shaped sealing rings are provided with a rough surface in a direction away from the slag discharge pipe (1).

10. A reverse circulation drilling rig, characterized in that: A drill pipe, a reverse circulation impactor connected to the drill pipe, and a filter joint according to any one of claims 1 to 9; in, The filter joint of the reverse circulation impactor is arranged between adjacent drill pipes; or, The filter joint of the reverse circulation impactor is arranged between the drill pipe and the reverse circulation impactor.

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