Long distance reaming device for horizontal directional drilling machine

Abstract

This invention relates to the field of horizontal directional drilling rigs, and more specifically, to a long-distance reaming device for horizontal directional drilling rigs, comprising: a drilling rig body, a drill rod at its drive end, a cylindrical connecting seat fixedly mounted at the free end of the drill rod, and a drilling bit detachably mounted at the end of the connecting seat away from the drill rod; when the drilling rig drives the drilling bit forward to drill, four sets of reaming drill bits can be automatically driven to extend outward synchronously by a hydraulic linkage structure, and complete the step-by-step reaming in sync with the main drill bit; during the retraction of the drilling drill bits, the hydraulic mechanism, in conjunction with the spring force, automatically completes the reset and retraction, without the need for manual operation of the opening and closing action; when the reaming drill bits are not in use, they can be completely stored inside the storage groove, with the overall outer diameter reduced to its minimum; during retraction and passage through the hole, there is no external protruding structure scraping or hooking against the hole wall, greatly reducing the faults of stuck drill, locked, and jammed during long-distance drilling and pullback.

Description

Technical Field

[0001] This invention relates to the field of horizontal directional drilling rigs, and more specifically, to a long-distance reaming device for horizontal directional drilling rigs. Background Technology

[0002] In the field of long-distance horizontal directional drilling, pilot hole drilling and progressive hole reaming are the core construction procedures. Existing conventional hole reaming devices mostly adopt a fixed external convex reaming drill bit structure, which cannot achieve autonomous retraction and adjustment according to the construction conditions.

[0003] First, traditional reaming drill bits are mostly permanently protruding structures that cannot be stored and hidden. During the lowering of the pilot hole, long-distance passage through the hole, and subsequent pullback and retraction, the exposed reaming drill bit is very likely to cause hard interference with the borehole wall, easily scraping and snagging the soil on the borehole wall. This can not only cause the borehole wall to collapse and the borehole diameter to deform, but also frequently cause drill bit jamming, seizing, and other failures, affecting the continuity and safety of long-distance horizontal directional drilling.

[0004] Secondly, existing hole-reaming devices generally lack the ability to adjust in conjunction with operating conditions. They cannot automatically expand to ream when the drill bit moves forward, nor can they automatically retract when the drill bit is withdrawn. They often require manual adjustment of the drill bit's opening and closing status, resulting in cumbersome operation procedures and low automation.

[0005] To address the aforementioned issues, a long-distance borehole reaming device for horizontal directional drilling rigs is proposed. Summary of the Invention

[0006] Technical problems to be solved To address the problems existing in the prior art, the present invention provides a long-distance reaming device for horizontal directional drilling rigs, which solves the problem that traditional reaming devices cannot automatically extend with drilling and retraction, resulting in the reaming drill bit being exposed and interfering with the borehole wall, causing jamming and hole hanging.

[0007] (II) Technical Solution To achieve the above objectives, the present invention provides the following technical solution: a long-distance borehole reaming device for horizontal directional drilling rigs, comprising: The drilling rig body has a drill rod at its drive end. A cylindrical connecting seat is fixedly installed at the free end of the drill rod. A drilling bit is detachably installed at the end of the connecting seat away from the drill rod. Four sets of extendable reaming drill bits are installed on the outer side of the arc surface of the connecting seat. The adjustment mechanism includes a storage groove on the outside of the connecting seat for storing the reaming drill bit, a bracket rotatably provided on the inner side of the storage groove, and a large hydraulic groove and a small hydraulic groove provided on one side of the storage groove for synchronously adjusting the extension and retraction of four sets of reaming drill bits. The inner side of the receiving groove is provided with a soil retaining component, which includes a baffle fixedly installed on the outside of the reaming drill bit.

[0008] The present invention is further configured such that a insertion groove is provided on the side of the drilling bit away from the drilling end, and a insertion end is provided on the end of the connecting seat away from the drill rod. The insertion end is inserted into the insertion groove, a limit groove is horizontally provided on the inner wall of the insertion groove, and a limit strip is horizontally fixedly installed on the outer side of the insertion end. The limit strip is slidably connected to the limit groove.

[0009] The invention is further configured such that a large piston is slidably connected inside the large hydraulic groove, a connecting block is fixedly installed on the side of the large piston away from the receiving groove, a fixing groove is opened in the middle of the inner wall of the insertion groove, and the fixing block is inserted into the fixing groove at one end placed outside the large hydraulic groove.

[0010] The present invention is further configured such that a settling groove is provided on the outer side of the drilling bit, and a fixing hole is provided on the outer side of the connecting block. The fixing hole corresponds to the settling groove, and the drilling bit and the connecting block are fixedly connected by bolts passing through the settling groove and the fixing hole.

[0011] The present invention is further configured such that there are four sets of small hydraulic grooves, each set of small hydraulic grooves corresponding to four sets of storage grooves, and one end of each small hydraulic groove is connected to the side of the large hydraulic groove away from the drilling bit, and a small piston is slidably connected inside each small hydraulic groove.

[0012] The present invention is further configured such that the middle part of the bracket is rotatably connected to the storage groove via a shaft pin, an adjusting rod is hinged to the hinge end of the bracket, a fixing sleeve is fixedly installed on the side of the reaming drill bit away from the reaming end, and the fixed end of the bracket is fixedly connected to the fixing sleeve of the reaming drill bit.

[0013] The invention is further configured such that a push rod is vertically mounted in the middle of the small piston, and one end of the push rod located outside the small hydraulic groove is hinged to the end of the adjusting rod away from the bracket.

[0014] The invention is further configured such that a spring is provided on the side of the small piston near the push rod, the spring is sleeved on the outside of the push rod, and the two ends of the spring are fixedly connected to the piston and the inner wall of the small hydraulic groove, respectively.

[0015] The present invention is further configured such that a retaining strip is fixedly installed on the inner wall of the receiving groove near the small hydraulic groove, and a limiting block is fixedly installed on the side of the receiving groove away from the retaining strip, and the limiting block is movably connected to one end of the retaining plate.

[0016] The present invention is further configured such that the four sets of the reaming drill bits are equidistantly distributed on the outside of the connecting seat, and the receiving groove is matched with the size of the reaming drill bits and the retaining plate.

[0017] (III) Beneficial Effects Compared with the prior art, the present invention provides a long-distance borehole reaming device for horizontal directional drilling rigs, which has the following beneficial effects: When the drilling rig drives the drilling bit forward to drill a hole, the hydraulic linkage structure can automatically drive four sets of reaming drill bits to extend outward synchronously, and complete the step-by-step reaming in sync with the main drill bit. During the retraction of the drilling bit, the hydraulic mechanism, in conjunction with the spring force, automatically completes the reset and retraction, without the need for manual operation of the opening and closing action. When the reaming drill bit is not in use, it can be completely stored inside the storage slot, with the overall outer diameter reduced to its minimum. During retraction and passage through the hole, there is no external protruding structure to scrape or snag the hole wall, which greatly reduces the failure of stuck drill, locked, or jammed during long-distance drilling and pullback.

[0018] The retaining plate swings open and closes synchronously with the reaming drill bit. The limiting block can constrain the position of the retracting plate after it is unfolded, indirectly providing lateral support to the reaming drill bit, reducing shaking and deviation during reaming cutting, and making the reaming drill bit's working posture more stable. The retaining strip and retaining plate can protect the receiving groove, effectively preventing soil, sand, and mud from entering the receiving groove during the reaming process and affecting the receiving of the reaming drill bit. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of a long-distance borehole reaming device for a horizontal directional drilling rig.

[0020] Figure 2 Cross-sectional view of the drilling and reaming bits for a long-distance reaming device used in horizontal directional drilling rigs.

[0021] Figure 3 for Figure 2 Enlarged view of point A.

[0022] Figure 4 A schematic diagram of a reaming drill bit used in a long-distance reaming device for horizontal directional drilling rigs during hole reaming.

[0023] In the diagram: 1. Drill rig body; 10. Drill rod; 100. Connecting seat; 101. Insertion end; 102. Drill bit; 103. Insertion groove; 104. Large hydraulic groove; 105. Large piston; 106. Connecting block; 107. Fixing groove; 108. Fixing hole; 109. Settling groove; 110. Bolt; 111. Limiting groove; 112. Limiting strip; 113. Storage groove; 2. Reaming drill bit; 20. Bracket; 201. Small hydraulic groove; 202. Small piston; 203. Push rod; 204. Adjusting rod; 205. Hinge end; 206. Shaft pin; 207. Spring; 208. Fixing end; 209. Retaining strip; 210. Retaining plate; 211. Limiting block; 212. Fixing sleeve; 3. Drilling end; 31. Reaming end. Detailed Implementation

[0024] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0025] It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0026] In this invention, unless otherwise stated, the directional terms such as "up" and "down" generally refer to the directions shown in the accompanying drawings, or to the vertical, perpendicular, or gravitational direction; similarly, for ease of understanding and description, "left" and "right" generally refer to the left and right shown in the accompanying drawings; "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0027] For examples, please refer to Figures 1-4 A long-distance reaming device for a horizontal directional drilling rig includes: a drilling rig body 1, with a drill rod 10 at its drive end, a cylindrical connecting seat 100 fixedly installed at the free end of the drill rod 10, a detachable drilling bit 102 at the end of the connecting seat 100 away from the drill rod 10, and four sets of extendable reaming bits 2 on the outer side of the arc-shaped surface of the connecting seat 100; an adjustment mechanism, including a receiving groove 113 on the outer side of the connecting seat 100 for receiving the reaming bits 2, a bracket 20 rotatably installed on the inner side of the receiving groove 113, and a large hydraulic groove 104 and a small hydraulic groove 201 on one side of the receiving groove 113 for synchronously adjusting the extension and retraction of the four sets of reaming bits 2; wherein, a soil-retaining assembly is installed on the inner side of the receiving groove 113, the soil-retaining assembly including a baffle fixedly installed on the outer side of the reaming bits 2.

[0028] In this embodiment, the drilling rig body 1 drives the drill rod 10 to rotate and advance forward. The connecting seat 100 at the end of the drill rod 10 moves synchronously, and the front drilling drill bit 102 completes the pilot hole drilling first. Four sets of retractable reaming drill bits 2 are arranged circumferentially on the outer side of the connecting seat 100. When the drilling drill bit 102 is drilling normally forward, the hydraulic system automatically builds up pressure according to the drilling conditions, and the large hydraulic groove 104 and the small hydraulic groove 201 are linked to drive the four sets of reaming drill bits 2 to unfold outward on their own, and synchronously follow the drilling drill bit 102 to complete the reaming operation. When the drilling is completed and the drilling drill bit is retracted, the hydraulic pressure is released, and the reaming drill bit 2 can automatically rotate back and be stored in the storage groove 113. A baffle is set on the outside of the reaming drill bit 2 to form a soil retaining component. As the reaming drill bit 2 extends, it swings to block the opening of the storage groove 113, preventing soil and sand from entering the groove, preventing debris from accumulating and causing the mechanism to jam, and ensuring that the reaming drill bit 2 can always be stored smoothly without obstruction.

[0029] The drilling bit 102 has a insertion groove 103 on the side away from the drilling end 3, and the connecting seat 100 has an insertion end 101 on the end away from the drill rod 10. The insertion end 101 is inserted into the insertion groove 103. A limit groove 111 is horizontally formed on the inner wall of the insertion groove 103. A limit strip 112 is horizontally fixed on the outer side of the insertion end 101. The limit strip 112 is slidably connected to the limit groove 111.

[0030] In this embodiment, the drilling bit 102 has an insertion groove 103 on the side opposite to the drilling end 3, and the connector 100 has an insertion end 101 at its end. During assembly, the insertion end 101 is inserted into the insertion groove 103 to achieve alignment. The inner wall of the insertion groove 103 has a limiting groove 111, and a limiting strip 112 is correspondingly installed on the outer side of the insertion end 101. The limiting strip 112 is adapted to slide within the limiting groove 111. This can transmit the rotational torque during drilling, keep the main drilling bit and the connector 100 running synchronously, and limit radial and circumferential offset, making the overall assembly structure stable and ensuring that it does not loosen or deviate during operation. At the same time, it can also play a foolproof role, aligning the settling groove 109 on the outer side of the drilling bit 102 with the fixing hole 108 on the outer side of the connector 106, making it convenient for workers to quickly install the drilling bit 102.

[0031] Specifically, a large piston 105 is slidably connected inside the large hydraulic groove 104. A connecting block 106 is fixedly installed on the side of the large piston 105 away from the receiving groove 113. A fixing groove 107 is opened in the middle of the inner wall of the insertion groove 103. One end of the fixing block is placed on the outside of the large hydraulic groove 104 and is inserted into the fixing groove 107.

[0032] In this embodiment, a large piston 105 that can slide axially is installed inside the large hydraulic groove 104. A connecting block 106 is fixedly connected to the outside of the large piston 105. A fixing groove 107 is provided on the inner wall of the insertion groove 103. The end of the connecting block 106 can be embedded in the fixing groove 107 of the drilling bit 102 to form a locking position, which facilitates the fixed connection between the drilling bit 102 and the connecting block 106. When the drilling bit 102 is drilling forward, the drilling bit 102 approaches the connecting seat 100. The drilling bit 102 can push the large piston 105 to move towards the reaming drill bit 2 in the large hydraulic groove 104 through the connecting block 106.

[0033] Furthermore, a settling groove 109 is provided on the outer side of the drilling bit 102, and a fixing hole 108 is provided on the outer side of the connecting block 106. The fixing hole 108 corresponds to the settling groove 109, and the drilling bit 102 and the connecting block 106 are fixedly connected by bolts 110 through the settling groove 109 and the fixing hole 108.

[0034] In this embodiment, a settling groove 109 is provided on the outer side of the drilling bit 102, and a fixing hole 108 is provided at the corresponding position of the connecting block 106. After the limiting strip 112 and the limiting groove 111 are limited, the two holes are automatically aligned. Then, the bolt 110 is used to lock and fix them through. The settling groove 109 can store the nut of the bolt 110, so as to avoid the bolt interfering with the normal use of the drilling bit 102 and can withstand the torque and tensile and compressive forces of long-distance horizontal drilling.

[0035] Furthermore, there are four sets of small hydraulic grooves 201, which correspond to four sets of storage grooves 113 respectively. One end of each small hydraulic groove 201 is connected to the side of the large hydraulic groove 104 away from the drilling bit 102. A small piston 202 is slidably connected inside each small hydraulic groove 201.

[0036] In this embodiment, four sets of small hydraulic grooves 201 are arranged in a one-to-one correspondence with four storage grooves 113, and all of them are connected to the large hydraulic groove 104. Each set of small hydraulic grooves 201 is equipped with a sliding small piston 202. When the drilling bit 102 is drilling forward, the drilling bit 102 can push the large piston 105 to move in the large hydraulic groove 104 through the connecting block 106. This can evenly distribute the hydraulic oil in the large hydraulic groove 104 to the four sets of small hydraulic grooves 201. Since the small pistons 202 are slidably connected in the small hydraulic grooves 201, they can synchronously push the four small pistons 202 to move in the same direction as the reaming drill bit 2, further realizing that the four sets of reaming drill bits 2 can synchronously and automatically expand the hole outward. When the drilling bit 102 is pulled back, the connecting block 106 can pull the large piston 105 to move in the opposite direction and reset, which can draw the hydraulic oil in the small hydraulic grooves 201 back into the large hydraulic groove 104, thereby driving each small piston 202 to reset synchronously, further driving the four sets of reaming drill bits 2 to synchronously and automatically retract inward, with consistent circumferential movements. It should be noted that sealing rings are provided on the outer sides of both the large piston 105 and the small piston 202, which can improve the sealing performance of the connection between the large piston 105 and the small piston 202 and the inner walls of the large hydraulic groove 104 and the small hydraulic groove 201, and the dimensions of the large hydraulic groove 104 and the small hydraulic groove 201 are matched.

[0037] Furthermore, the middle part of the bracket 20 is rotatably connected to the storage groove 113 via a shaft pin 206, and an adjusting rod 204 is hinged to the hinge end 205 of the bracket 20. A fixing sleeve 212 is fixedly installed on the side of the reaming drill bit 2 away from the reaming end 31, and the fixing end 208 of the bracket 20 is fixedly connected to the fixing sleeve 212 of the reaming drill bit 2.

[0038] In this embodiment, during the drilling operation, the adjusting rod 204 is pushed and pulled by the hydraulic transmission force, which drives the bracket 20 to rotate around the shaft pin 206, and in turn swings the reaming drill bit 2 out of the storage groove 113 and unfolds it to participate in the reaming; when the drilling ends and the drill bit is retracted, the mechanism rotates in the opposite direction to rotate the reaming drill bit 2 back into the storage groove 113. The entire process relies on mechanical hinge linkage to achieve automatic opening and closing according to the working conditions.

[0039] Furthermore, a push rod 203 is vertically mounted in the middle of the small piston 202, and one end of the push rod 203 located outside the small hydraulic groove 201 is hinged to the end of the adjusting rod 204 away from the bracket 20.

[0040] In this embodiment, the small piston 202 slides linearly under hydraulic pressure, driving the push rod 203 to move forward and backward synchronously, thereby pushing and pulling the adjusting rod 204 to swing. The hydraulic linear motion is smoothly converted into the rotational swing of the bracket 20 and the reaming drill bit 2, so as to automatically push open the reaming drill bit 2 to unfold when drilling forward and automatically pull it back to retract when retracting, so that the transmission is smooth and continuous.

[0041] A spring 207 is provided on the side of the small piston 202 near the push rod 203. The spring 207 is sleeved on the outside of the push rod 203, and the two ends of the spring 207 are fixedly connected to the piston and the inner wall of the small hydraulic groove 201, respectively.

[0042] In this embodiment, during forward drilling, the hydraulic pressure overcomes the elastic force of the spring 207 to push the small piston 202 and push rod 203 forward, causing the reaming drill bit 2 to expand outward and enlarge the hole. At this time, the spring 207 is compressed. When drilling stops and the drilling drill bit is retracted, the hydraulic pressure disappears. The elastic force of the spring 207 itself can assist in pushing the small piston 202 back to its original position, causing the push rod 203, adjusting rod 204, and bracket 20 to swing back in unison, so that the reaming drill bit 2 automatically returns to its original position in the storage slot 113. The reaming is achieved by relying on the energy stored in the spring 207, without the need for additional manual operation.

[0043] Preferably, a retaining strip 209 is fixedly installed on the inner wall of the receiving groove 113 near the small hydraulic groove 201, and a limiting block 211 is fixedly installed on the side of the receiving groove 113 away from the retaining strip 209. The limiting block 211 is movably connected to one end of the retaining plate 210.

[0044] In this embodiment, by installing a limiting block 211 on the side, during the unfolding process of the reaming drill bit 2, the retaining plate 210 on the outside of the reaming drill bit 2 rotates from a vertical state to a horizontal state. The limiting block 211 can limit the retaining plate 210, so that the retaining plate 210 is pressed against the outside of the limiting block 211, which can improve the stability of the reaming drill bit 2. At this time, the retaining plate 210 and the retaining strip 209 can protect the receiving groove 113, preventing soil and mud from entering the receiving groove 113 and avoiding soil and mud from affecting the receiving of the reaming drill bit 2.

[0045] It should be noted that the four sets of reaming drill bits 2 are equidistantly distributed on the outside of the connecting seat 100, and the receiving groove 113 is matched with the size of the reaming drill bits 2 and the retaining plate 210.

[0046] In this embodiment, the four sets of reaming drill bits 2 are arranged at equal intervals to ensure uniform force during reaming and regular hole formation. This results in low resistance and minimal deviation during long-distance drilling. The size of the storage groove 113 is adapted to allow the reaming drill bits 2 to be completely stored inside the groove, minimizing the outer diameter of the entire machine. When the drilling drill bit is retracted, there is no outward protrusion scraping the hole wall, avoiding jamming and hole snagging. This design is suitable for long-distance horizontal directional dragging operations.

[0047] Of all the solutions mentioned above, those involving the connection between two components can be selected according to the actual situation, such as welding, bolt and nut connection, bolt or screw connection, or other known connection methods, which will not be elaborated here. For all the fixed connections mentioned above, welding is preferred. Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A long-distance reaming device for a horizontal directional drilling rig, characterized in that, include: The drilling rig body (1) has a drill rod (10) at its drive end. A cylindrical connecting seat (100) is fixedly installed at the free end of the drill rod (10). A drilling bit (102) is detachably installed at the end of the connecting seat (100) away from the drill rod (10). Four sets of extendable reaming bits (2) are installed on the outer side of the arc surface of the connecting seat (100). The adjustment mechanism includes a storage groove (113) on the outside of the connecting seat (100) for storing the reaming drill bit (2), a bracket (20) is rotatably provided on the inside of the storage groove (113), and a large hydraulic groove (104) and a small hydraulic groove (201) are provided on one side of the storage groove (113) for synchronously adjusting the extension and storage of the four sets of reaming drill bits (2). The inner side of the receiving groove (113) is provided with a soil retaining component, which includes a baffle fixedly installed on the outside of the reaming drill bit (2).

2. The long-distance reaming device for a horizontal directional drilling rig according to claim 1, characterized in that: The drilling bit (102) has a plug groove (103) on the side away from the drilling end (3). The connecting seat (100) has a plug end (101) on the end away from the drill rod (10). The plug end (101) is plugged into the plug groove (103). The inner wall of the plug groove (103) has a horizontal limit groove (111). The outer side of the plug end (101) is horizontally fixed with a limit strip (112). The limit strip (112) is slidably connected to the limit groove (111).

3. A long-distance reaming device for a horizontal directional drilling rig according to claim 2, characterized in that: A large piston (105) is slidably connected inside the large hydraulic groove (104). A connecting block (106) is fixedly installed on the side of the large piston (105) away from the receiving groove (113). A fixing groove (107) is opened in the middle of the inner wall of the insertion groove (103). The fixing block is placed at one end outside the large hydraulic groove (104) and inserted into the fixing groove (107).

4. A long-distance reaming device for a horizontal directional drilling rig according to claim 3, characterized in that: The outer side of the drilling bit (102) is provided with a settling groove (109), and the outer side of the connecting block (106) is provided with a fixing hole (108). The fixing hole (108) corresponds to the settling groove (109), and the drilling bit (102) and the connecting block (106) are fixedly connected by bolts (110) through the settling groove (109) and the fixing hole (108).

5. A long-distance reaming device for a horizontal directional drilling rig according to claim 4, characterized in that: The number of small hydraulic grooves (201) is four sets. The four sets of small hydraulic grooves (201) correspond to the four sets of storage grooves (113) respectively. One end of the small hydraulic groove (201) is connected to the side of the large hydraulic groove (104) away from the drilling bit (102). A small piston (202) is slidably connected inside the small hydraulic groove (201).

6. A long-distance reaming device for a horizontal directional drilling rig according to claim 1, characterized in that: The middle part of the bracket (20) is rotatably connected to the storage groove (113) via a shaft pin (206). An adjusting rod (204) is hinged to the hinge end (205) of the bracket (20). A fixing sleeve (212) is fixedly installed on the side of the reaming drill bit (2) away from the reaming end (31). The fixed end (208) of the bracket (20) is fixedly connected to the fixing sleeve (212) of the reaming drill bit (2).

7. A long-distance reaming device for a horizontal directional drilling rig according to claim 5, characterized in that: A push rod (203) is vertically mounted in the middle of the small piston (202). One end of the push rod (203) is located outside the small hydraulic groove (201) and is hinged to the end of the adjusting rod (204) away from the bracket (20).

8. A long-distance reaming device for a horizontal directional drilling rig according to claim 7, characterized in that: A spring (207) is provided on the side of the small piston (202) near the push rod (203). The spring (207) is sleeved on the outside of the push rod (203), and the two ends of the spring (207) are fixedly connected to the piston and the inner wall of the small hydraulic groove (201), respectively.

9. A long-distance reaming device for a horizontal directional drilling rig according to claim 8, characterized in that: A retaining strip (209) is fixedly installed on the inner wall of the storage groove (113) near the small hydraulic groove (201). A limiting block (211) is fixedly installed on the side of the storage groove (113) away from the retaining strip (209). The limiting block (211) is movably connected to one end of the retaining plate (210).

10. A long-distance reaming device for a horizontal directional drilling rig according to claim 1, characterized in that: four sets The reaming drill bit (2) is equidistantly distributed on the outside of the connecting seat (100), and the receiving groove (113) is matched with the size of the reaming drill bit (2) and the retaining plate (210).

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