A down-the-hole percussion drill string

Abstract

The utility model relates to a kind of down-the-hole percussion type cylinder drill, including drill pipe, cylinder drill and deslagging system, the drill pipe is equipped with first fluid passage and first deslagging passage independent of each other;Several down-the-hole hammers are uniformly arranged in the cylinder wall of the cylinder drill along the circumferential direction, the down-the-hole hammer is equipped with percussion drill bit in the bottom end of cylinder drill cylinder wall, and one cone is equipped between every two adjacent percussion drill bit;The deslagging system includes hole sealing device being located at the outer wall of drill pipe and adapter assembly being located between drill pipe and cylinder drill, the inside of the adapter assembly is equipped with second fluid passage being communicated with first fluid passage and second deslagging passage being communicated with first deslagging passage, and outer deslagging port being communicated with second deslagging passage is equipped on the lateral wall of adapter assembly.Compared with prior art, the utility model has high rock breaking efficiency, low energy consumption, efficient deslagging and simple and reliable structure.

Description

Technical Field

[0001] This utility model relates to the field of drilling machinery technology, and in particular to a down-the-hole impact drill. Background Technology

[0002] In pile foundation engineering for buildings, subway stations, and other structures, the borehole diameter typically ranges from 0.8 to 1.2 meters, and can even reach 1.5 meters; the borehole depth is usually between 10 and 50 meters, requiring penetration into bedrock at a depth of 10 to 30 meters. Currently, core drills or cluster hammers are commonly used as the core equipment for rock breaking in pile foundation engineering. Traditional core drills experience a sharp drop in drilling speed after entering the rock strata in the later stages of construction, typically advancing less than 1 meter per hour, severely impacting construction efficiency. If the project schedule is tight, additional equipment is required, but this significantly increases construction costs. While cluster hammers can be used for full-face rock breaking drilling, the large borehole diameter in pile foundations typically requires 8 to 10 impactors with a diameter of 250mm. Equipping these large-sized and numerous impactors significantly increases the overall weight of the equipment, air supply requirements, and energy consumption.

[0003] To address the aforementioned issues, existing technologies have provided relevant solutions. For example, Chinese patent CN114016897A discloses a reverse circulation impactor and system, including a drill rod component and a core sampling component. The drill rod component and the core sampling component are integrally formed, with the drill rod component positioned above the core sampling component. The core sampling component includes a core impactor. The bottom of the core impactor cylinder is annular, with multiple reverse circulation sub-down-the-hole hammers spaced apart on the annulus. The drill rod component provides a high-pressure air channel to the core impactor. This solution can effectively improve the drilling efficiency of large-diameter impactors and reduce the cost of drill bit consumption. However, relying solely on sub-down-the-hole hammers for circumferential cutting results in low rock-breaking efficiency, limiting the overall improvement in drilling efficiency.

[0004] Chinese patent CN213775271U discloses a barrel drill, comprising a barrel drill body connected to the drill rod of a rotary drilling rig. The barrel drill body has an inner drill barrel, an outer drill barrel, and two ventilation pipes. The outer drill barrel contains multiple down-the-hole hammers, each with its bottom end extending beyond the bottom plate of the outer drill barrel. The bottom plate of the outer drill barrel between adjacent down-the-hole hammers has multiple cutting teeth. The bottom surface of the inner drill barrel's bottom plate has multiple ball-tooth hobs. The bottom plate of the inner drill barrel also has at least one slag suction port connected to an air-lift reverse circulation slag discharge pipe. This design can significantly improve rock-breaking efficiency and enhance the air-lift slag discharge effect through structures such as the air-lift reverse circulation slag discharge pipe and ventilation pipes. However, relying solely on the suction port of the inner drill pipe bottom plate to suck mud into the slag discharge system has limited actual improvement in slag discharge efficiency. Both the inner and outer drill pipes participate in rock breaking, which improves rock breaking efficiency, but consumes a lot of energy. In addition, a sealing strip is required at the bottom of the connection between the inner and outer drill pipes to prevent mud and debris from entering the gap between them. The structure is complex and not conducive to maintenance.

[0005] In summary, existing drilling equipment cannot simultaneously achieve rock breaking efficiency, energy consumption control, slag removal capacity, and structural reliability, making it difficult to carry out efficient and low-cost construction in drilling conditions of large-diameter hard rock. Summary of the Invention

[0006] The technical problem to be solved by this utility model is to provide a down-the-hole impact drill that has high rock breaking efficiency, low energy consumption, high slag removal efficiency and simple and reliable structure.

[0007] To solve the above-mentioned technical problems, the technical solution provided by this utility model is as follows: A down-the-hole percussion drill bit, comprising: The drill pipe is provided with a first fluid channel and a first slag discharge channel that are independent of each other; A cylindrical drill, wherein several down-the-hole impactors are evenly arranged in the circumferential direction in the cylindrical wall of the cylindrical drill, and the down-the-hole impactors are provided with impact drill bits at the bottom end of the cylindrical wall of the cylindrical drill, and a toothed cone is provided between every two adjacent impact drill bits. The slag removal system includes a sealing device on the outer wall of the drill rod and a transfer assembly between the drill rod and the barrel drill. The transfer assembly has a second fluid channel communicating with the first fluid channel and a second slag removal channel communicating with the first slag removal channel inside. The side wall of the transfer assembly has an external slag removal port communicating with the second slag removal channel.

[0008] The beneficial effects of this plan are:

[0009] (1) This utility model forms a composite rock breaking mechanism that combines impact crushing and rolling shearing by arranging the impact drill bit and roller cone of the down-the-hole impactor at intervals at the bottom of the cylinder wall of the cylinder, thereby improving the rock breaking efficiency; and adopts ring cutting core cutting for rock breaking, which has high drilling efficiency, reduces the number of impactors, and has low energy consumption.

[0010] (2) Compared with traditional tubular drills which only suck mud and slag inside the tubular drill, this utility model can also suck mud and slag in the gap between the tubular drill and the borehole wall through the sealing device and the external slag discharge port set on the adapter, thereby improving the slag discharge efficiency and preventing slag and debris from overflowing and polluting the well wall and the environment. Moreover, the structure is simple and reliable.

[0011] Furthermore, the sealing device is a bladder-type variable diameter sealing device that expands after compressed air or water is introduced, and a support part is provided on the outer wall of the drill rod, and the sealing device is connected to the support part.

[0012] The beneficial effects of this scheme are as follows: the use of a bladder-type variable diameter sealing device can adapt to different hole diameters or hole wall shapes, effectively sealing the annular gap between the drill rod and the hole wall, creating sealed conditions for reverse circulation slag removal.

[0013] Furthermore, the adapter assembly is provided with a partition on the upper end face of the drill bit, and the partition is provided with an internal slag discharge port that communicates with the interior of the drill bit.

[0014] Furthermore, the adapter assembly is provided with an inner slag discharge pipe that connects the second slag discharge channel and the inner slag discharge port.

[0015] Furthermore, the cylinder wall of the drill bit is provided with a connecting rod for connecting the down-the-hole impactor and the partition plate. The connecting rod is hollow inside and communicates with the inside of the down-the-hole impactor.

[0016] Furthermore, the partition is provided with a fluid inlet that connects the second fluid channel to the interior of the connecting rod.

[0017] Furthermore, the second fluid channel is a high-pressure chamber and is connected to all the fluid inlets.

[0018] The beneficial effect of this scheme is that by setting the second fluid channel as a common high-pressure chamber connected to all fluid inlets, the power fluid can be evenly supplied to all down-the-hole impactors, making the impact drill bit act uniformly, thereby ensuring the flatness and verticality of the circumferential groove.

[0019] Furthermore, the adapter assembly is provided with a jet nozzle that connects the second fluid channel and the second slag discharge channel, with the nozzle orifice facing the second slag discharge channel.

[0020] The beneficial effects of this scheme are: by utilizing the Venturi effect, a portion of the high-pressure kinetic fluid is generated in the second slag discharge channel through a jet nozzle to form a strong negative pressure, thereby enabling active and efficient suction of sludge. Compared with traditional air-lift slag discharge, it has stronger power and higher slag discharge efficiency.

[0021] Furthermore, the jet nozzle is located directly below the first slag discharge channel, with its nozzle facing the first slag discharge channel. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of a down-the-hole percussion drill in this embodiment.

[0023] Figure 2 This is a schematic diagram of the adapter component in this embodiment.

[0024] Figure 3 This is a schematic diagram showing the arrangement of the impact drill bit and roller cone in this embodiment.

[0025] Figure 4 This is a top view of the down-the-hole percussion drill in this embodiment.

[0026] Figure 5This is a schematic diagram of the structure of the down-the-hole percussion drill in operation in this embodiment.

[0027] Figures 1-5 middle: 1. Drill pipe; 11. First fluid channel; 12. First slag discharge channel; 13. Support unit; 2. Tube drill; 21. Down-the-hole hammer; 22. Impact drill bit; 23. Roller cone; 24. Connecting rod; 3. Slag discharge system; 31. Sealing device; 311. Air inlet; 32. Adapter assembly; 321. Second fluid channel; 322. Second slag discharge channel; 323. External slag discharge port; 324. Baffle; 3241. Internal slag discharge port; 3242. Fluid inlet; 325. Internal slag discharge pipe; 326. Jet nozzle. Detailed Implementation

[0028] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present utility model and are not intended to limit the present utility model.

[0029] In the description of this utility model, it should be understood that the terms "upper", "lower", "front", "rear", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0030] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation", "connection" and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, an integral connection, or a detachable connection; they can refer to the internal connection of two components; they can refer to a direct connection or an indirect connection through an intermediate medium. For those skilled in the art, the specific meaning of the above terms in this utility model can be understood according to the specific circumstances.

[0031] like Figure 1 As shown, a down-the-hole percussion drill of this embodiment includes a drill rod 1, a drill 2, and a slag removal system 3. The drill rod 1 is provided with a first fluid channel 11 and a first slag removal channel 12 that are independent of each other, and there are two first slag removal channels 12; a plurality of down-the-hole impactors 21 are evenly arranged in the circumferential direction in the cylinder wall of the drill 2, and the down-the-hole impactors 21 are provided with impact drill bits 22 at the bottom end of the cylinder wall of the drill 2.

[0032] As a special feature of this embodiment, such as Figure 1 and Figure 3 As shown, a toothed cone 23 is provided between every two adjacent impact drill bits 22.

[0033] The advantage of this setup is that by arranging the impact drill bit 22 and roller cone 23 of the down-the-hole hammer 21 at intervals at the bottom end of the cylinder wall of the barrel drill 2, a composite rock breaking process combining impact crushing and rolling shearing is formed, which improves rock breaking efficiency; and by using ring cutting core cutting for rock breaking, the drilling efficiency is high, the number of impactors is reduced, and energy consumption is low.

[0034] Preferably, in this embodiment, six impact drill bits 22 and six roller cones 23 are provided.

[0035] As another special feature of this embodiment, such as Figure 1 and Figure 2 As shown, the slag discharge system 3 includes a sealing device 31 on the outer wall of the drill rod 1 and a transfer assembly 32 between the drill rod 1 and the barrel drill 2. The transfer assembly 32 has a second fluid channel 321 communicating with the first fluid channel 11 and a second slag discharge channel 322 communicating with the first slag discharge channel 12. The side wall of the transfer assembly 32 has an external slag discharge port 323 communicating with the second slag discharge channel 322.

[0036] The advantage of this design is that, compared to traditional tubular drills that only suck mud from inside the tubular drill 2, this embodiment, through the sealing device 31 and the external slag discharge port 323 provided on the adapter 32, can also suck mud from the gap between the tubular drill 2 and the borehole wall, improving slag discharge efficiency and preventing slag from overflowing and polluting the well wall and the environment. Moreover, the structure is simple and reliable.

[0037] Preferably, in this embodiment, the adapter component 32 has a partition 324 on the upper end face of the drill 2, and the partition 324 has an inner slag discharge port 3241 that communicates with the interior of the drill 2. Further, in this embodiment, the adapter component 32 has an inner slag discharge pipe 325 that communicates with the second slag discharge channel 322 and the inner slag discharge port 3241.

[0038] Preferably, in this embodiment, the sealing device 3 has the following structure: Figure 1 , Figure 4 and Figure 5 As shown. The sealing device 3 is a bladder-type variable diameter sealing device that expands by introducing compressed air, and an air inlet 311 is provided at the upper end of the sealing device 3. A support part 13 is provided on the outer wall of the drill rod 1, and the sealing device 3 is connected to the support part 13.

[0039] The advantage of this setup is that the use of a bladder-type variable diameter sealing device can adapt to different hole diameters or hole wall shapes, effectively sealing the annular gap between the drill rod 1 and the borehole wall, creating a sealed condition for reverse circulation slag discharge.

[0040] It should be noted that the use of a bladder-type variable diameter sealing device as the sealing device 3 is only a preferred embodiment of this invention. Those skilled in the art should understand that the sealing device 3 can also use other sealing equipment according to actual engineering needs. In addition, the bladder-type variable diameter sealing device can also be expanded by water flow.

[0041] As a preferred embodiment, in this case, Figure 1 As shown, the cylinder wall of the drill 2 is provided with a connecting rod 24 for connecting the down-the-hole impactor 21 and the partition plate 324. The connecting rod 24 is hollow and communicates with the interior of the down-the-hole impactor 21. Further, in this embodiment, as... Figure 1 and Figure 2 As shown, the partition 324 is provided with a fluid inlet 3242 that connects the second fluid channel 321 and the interior of the connecting rod 24.

[0042] Preferably, in this embodiment, the second fluid channel 321 is a high-pressure chamber and is connected to all fluid inlets 3242.

[0043] The advantage of this configuration is that by setting the second fluid channel 322 as a common high-pressure chamber connected to all fluid inlets 3242, the power fluid can be evenly supplied to all down-the-hole impactors 21, so that the impact drill bit 22 can act evenly, thereby ensuring the flatness and verticality of the circumferential groove.

[0044] It should be noted that, in Figure 2 In the diagram, the second fluid channel 321 is shown as three areas, which are actually interconnected in the same common area.

[0045] Preferably, in this embodiment, the adapter assembly 32 is provided with a jet nozzle 326 that connects the second fluid channel 321 and the second slag discharge channel 322, and the nozzle orifice of the jet nozzle 326 faces the second slag discharge channel 322. Further, in this embodiment, the jet nozzle 326 is located directly below the first slag discharge channel 12, and its nozzle faces the first slag discharge channel 12.

[0046] The advantage of this setup is that by utilizing the Venturi effect, a portion of the high-pressure kinetic fluid is directed through the jet nozzle 326 to form a strong negative pressure within the second slag discharge channel 322, thereby enabling the active and efficient extraction of sludge. Compared to traditional air-lift slag discharge, this setup offers stronger power and higher slag discharge efficiency.

[0047] like Figure 5As shown, during actual construction, the operator uses compressed air or high-pressure water as the power fluid, which passes sequentially through the first fluid channel 11 of the drill rod 1, the second fluid channel 321 of the adapter assembly 32, and the fluid inlet 3242 of the baffle 324, before entering the down-the-hole impactor 21 through the connecting rod 24. This drives the impact drill bit 22 to strike and break the rock. Simultaneously, the external drilling equipment rotates the drill rod 1, causing the tubular drill 2 to rotate, making the impact drill bit 22 and the roller cone 23 work along a circular trajectory, thus forming an annular groove. The mud or debris generated by the impact drill bit 2 and the roller cone 23 breaking the rock enters the second slag discharge channel 322 through the outer slag discharge port 323 along the gap between the borehole wall and the outer wall of the tubular drill 2, or enters the second slag discharge channel 322 sequentially through the inner slag discharge port 3241 and the inner slag discharge pipe 325 along the inner side of the tubular drill 2. Finally, with the assistance of the jet nozzle 326, the sludge or debris is rapidly transported from the second sludge discharge channel 322 to the first fluid channel 11 and discharged upwards to the ground by the sludge treatment equipment.

[0048] In summary, the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A down-the-hole percussion drill, characterized in that, include: The drill pipe (1) is provided with a first fluid channel (11) and a first slag discharge channel (12) that are independent of each other. A barrel drill (2) has several down-the-hole impactors (21) evenly arranged in the circumferential direction in the barrel wall of the barrel drill (2). The down-the-hole impactors (21) are provided with impact drill bits (22) at the bottom end of the barrel wall of the barrel drill (2), and a toothed cone (23) is provided between every two adjacent impact drill bits (22). The slag discharge system (3) includes a sealing device (31) on the outer wall of the drill rod (1) and a transfer assembly (32) between the drill rod (1) and the tubular drill (2). The transfer assembly (32) has a second fluid channel (321) communicating with the first fluid channel (11) and a second slag discharge channel (322) communicating with the first slag discharge channel (12). The transfer assembly (32) has an external slag discharge port (323) communicating with the second slag discharge channel (322) on its side wall.

2. The down-the-hole percussion drill according to claim 1, characterized in that, The sealing device (31) is a bladder-type variable diameter sealing device that expands after compressed air or water is introduced. The outer wall of the drill rod (1) is provided with a support part (13), and the sealing device (31) is connected to the support part (13).

3. The down-the-hole percussion drill according to claim 1, characterized in that, The adapter assembly (32) has a partition (324) on the upper end face of the drill bit (2), and the partition (324) has an internal slag discharge port (3241) that connects to the interior of the drill bit (2).

4. The down-the-hole percussion drill according to claim 3, characterized in that, The adapter assembly (32) is provided with an inner slag discharge pipe (325) that connects the second slag discharge channel (322) and the inner slag discharge port (3241).

5. The down-the-hole percussion drill according to claim 3, characterized in that, The cylinder wall of the drill bit (2) is provided with a connecting rod (24) for connecting the down-the-hole impactor (21) and the partition plate (324). The connecting rod (24) is hollow inside and communicates with the inside of the down-the-hole impactor (21).

6. The down-the-hole percussion drill according to claim 5, characterized in that, The partition (324) is provided with a fluid inlet (3242) that connects the second fluid channel (321) and the interior of the connecting rod (24).

7. The down-the-hole percussion drill according to claim 6, characterized in that, The second fluid channel (321) is a high-pressure chamber and is connected to all the fluid inlets (3242).

8. The down-the-hole percussion drill according to any one of claims 1-7, characterized in that, The adapter assembly (32) is provided with a jet nozzle (326) that connects the second fluid channel (321) and the second slag discharge channel (322), and the nozzle (326) faces the second slag discharge channel (322).

9. The down-the-hole percussion drill according to claim 8, characterized in that, The jet nozzle (326) is located directly below the first slag discharge channel (12), with its nozzle facing the first slag discharge channel (12).

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