A mine wear-resistant active drag-reducing drill pipe for underground coal mine and a use method thereof

Abstract

The application discloses a kind of coal mine underground mining wear-resistant active resistance-reducing drill pipe and its use method, including drill pipe body, spiral steel sheet is arranged around the outer wall of drill pipe body, spiral steel sheet is arranged along the length direction of drill pipe body, ball is rotationally arranged on the side wall of spiral steel sheet away from drill pipe body, part of ball is located in spiral steel sheet, another part is located outside spiral steel sheet.In using the application, after setting the position of drilling machine and the angle of holder, the drill bit is connected with the new wear-resistant resistance-reducing drill pipe, and then the drill bit and the drill pipe are clamped with the holder, the drill bit and the drill pipe are rotated and drilled into the coal wall or rock wall, the coal slag and rock slag generated during drilling are discharged from the drill hole through the spiral steel sheet, the rotatable ball embedded on the spiral steel sheet, the resistance during drilling process is reduced, the efficiency is improved, the drill pipe wear is reduced, and the friction heat is reduced.For the service life of drill pipe, drilling efficiency and construction safety, all have been improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mine drill pipes, in particular to a coal mine underground mine wear-resistant active drag-reducing drill pipe and a use method thereof. BACKGROUND

[0002] With the movement of coal resource exploitation downward, the gas content of coal seams, ground stress and gas pressure increase, making drilling more difficult. Drilling is an important step and key means for underground gas extraction and stress concentration elimination. In the drilling process of soft coal and rock strata, the deformation of the drill hole is large, and it is prone to instability and hole collapse. The drilling resistance is large, and the residue is difficult to discharge, which seriously hinders the drilling efficiency and the service life of the drill pipe.

[0003] To ensure the drilling rate and the service life of the drill pipe, a suitable drill pipe must be used. For example, a high-efficiency drill pipe with fast residue discharge speed disclosed in a Chinese utility model patent with the authorization announcement date of August 14, 2020 and the authorization announcement number of CN 211258532 U, which comprises a drill pipe body, the drill pipe body comprises a plug joint and a spiral blade, the spiral blade comprises an outer spiral blade and an inner spiral blade, the plug joint is provided with a breaking point A on one side, and the outer spiral blade and the inner spiral blade are provided on the other side of the breaking point A. Although the spiral blade can improve the residue discharge efficiency, a large amount of heat is generated by the sliding friction between the spiral blade and the drill pipe and the rock residue and coal residue.

[0004] However, according to the strength properties of coal seams and rock strata, the drill pipe still has large resistance, large friction and large heat generation when the outer wall of the drill pipe is attached to the coal wall during the drilling construction process. In severe cases, it can cause gas disasters. At the same time, long-term friction and heat accumulation can accelerate the wear of the drill pipe. SUMMARY

[0005] In view of the deficiencies in the above background art, the present application provides a coal mine underground mine wear-resistant active drag-reducing drill pipe and a use method thereof, which solves the technical problem of large friction resistance and large heat generation caused by the attachment of the outer wall of the existing mine drill pipe to the coal wall.

[0006] The technical scheme of the present application is as follows:

[0007] A coal mine underground mine wear-resistant active drag-reducing drill pipe, comprising a drill pipe body, a spiral steel sheet is arranged around the outer wall of the drill pipe body, the spiral steel sheet is arranged along the length direction of the drill pipe body, a plurality of rolling balls are arranged on the side wall of the spiral steel sheet away from the drill pipe body, and a part of the rolling balls is located inside the spiral steel sheet and the other part is located outside the spiral steel sheet.

[0008] Furthermore, the spiral steel sheet is provided with an installation groove, a part of the ball is disposed in the installation groove and another part protrudes from the installation groove, and a positioning plate is provided between the ball and the installation groove. When the ball comes into contact with the hole wall or drill cuttings, the ball rotates in the installation groove.

[0009] Alternatively, the spiral steel sheet may have an installation groove, which is a frustum-shaped structure. The outer groove opening at the outer edge of the spiral steel sheet is smaller than the inner groove opening at the drill pipe body, and the diameter of the outer groove opening is smaller than the diameter of the ball bearing. During assembly, the ball bearing is first installed in the installation groove, and then the spiral steel sheet 3 is welded segment by segment to the outer wall of the drill pipe body.

[0010] Furthermore, the mounting groove is connected to the high-pressure medium channel inside the drill rod body.

[0011] Furthermore, the ball bearings are arranged at equal intervals along the extension direction of the spiral steel sheet.

[0012] Furthermore, the cross-section of the spiral steel sheet is trapezoidal, and the pitch of the spiral steel sheet is the same along the length of the drill rod.

[0013] Furthermore, one end of the drill rod body is provided with an external thread structure and the other end is provided with an internal thread structure. The drill bit is connected to the rotating rod body through the internal thread structure. Adjacent drill rod bodies are connected through mutually cooperating external thread structures and internal thread structures.

[0014] Furthermore, the outline of the external thread structure of the drill pipe is frustum-shaped.

[0015] Furthermore, the diameter of the drill bit is larger than the diameter of the drill rod body, and the vertical distance between the outer circumferential surface of the spiral steel sheet and the outer circumferential surface of the drill rod body is smaller than the vertical distance between the outer circumferential surface of the drill bit and the outer circumferential surface of the drill rod body.

[0016] A method for using a wear-resistant active resistance-reducing drill pipe for underground coal mines, comprising the wear-resistant active resistance-reducing drill pipe for underground coal mines as described above, the method comprising the following steps:

[0017] Step 1: During the implementation process, first fix the drilling rig in the predetermined position and adjust the angle. Select the required size of the drill bit according to the diameter of the borehole. The rotating rod body is connected to the drill bit through the external thread structure of the drill rod. At the same time, it is required that the outer diameter of the drill bit is slightly larger than the overall outer diameter of the wear-resistant active resistance-reducing drill rod used in underground coal mines.

[0018] Step 2: Clamp the end of the wear-resistant active resistance-reducing drill rod for underground coal mines with the drill rig holder, turn on the drill rig to start rotating at a constant speed and drill into the coal wall at a predetermined angle;

[0019] Step 3: When the borehole is deep and a large number of drill rods are required, after one coal mine wear-resistant active resistance-reducing drill rod is drilled into the coal seam, a new coal mine wear-resistant active resistance-reducing drill rod is connected to the tail of the drill rod after it has entered the coal seam to extend the total length of the drill rod.

[0020] Step 4: When extending the total length of the drill rod, the internal thread structure of the drill rod at the tail of the previous wear-resistant active resistance-reducing drill rod for underground coal mines is tightened with the external thread structure of the drill rod at the end of the next wear-resistant active resistance-reducing drill rod for underground coal mines. The tightening direction is opposite to the rotation direction of the drilling machine and continues to extend into the borehole. Repeat steps 3 and 4 to connect the drill rods in sequence. When the predetermined depth is reached, the drill rods and drill bits are pulled out, and the drilling ends.

[0021] Furthermore, both the spiral steel sheet and the drill rod body are prefabricated structures. The spiral steel sheet is welded onto the outer wall of the drill rod body. During drilling, the spiral steel sheet provides protection for the drill rod body while the coal slag from the drill bit accumulates around the drill rod body. As the borehole deepens, the resistance between the drill cuttings and the wear-resistant active resistance-reducing drill rod used in underground coal mines gradually increases. The friction between the sidewall of the spiral steel sheet and the drill cuttings discharges the drill cuttings from the borehole. During drilling, when the ball bearings come into contact with the borehole wall or drill cuttings, the ball bearings form rolling friction with the borehole wall or drill cuttings, thereby reducing heat generation by reducing frictional resistance.

[0022] Compared with existing technologies, this invention has a scientific principle and compact structure. It connects to the drill bit during use. During drilling, the drill rod is clamped at a certain angle by the drill rig holder and rotates towards the coal wall. The drill bit breaks up the coal and rock mass and drills into the borehole. The spiral steel blades carry out drill cuttings and debris through friction. The rotation of the ball bearings converts the sliding friction between the drill rod and the coal wall into rolling friction, reducing resistance and extending the service life of the drill rod while ensuring a high hole formation rate. Simultaneously, the ball bearings reduce heat generation, lowering the risk of coal and gas disasters during drilling and providing safety assurance for the drilling process.

[0023] This invention is used in the drilling process of gas drainage boreholes and stress relief boreholes. After setting the drill rig position and clamp angle according to the pre-set drilling position and angle, the drill bit is connected to a new type of wear-resistant and resistance-reducing drill rod and clamped together. The rotation of the hydraulic drill rig drives the drill bit and drill rod to rotate and drill into the coal or rock wall, ultimately drilling to the required depth. During drilling, the external spiral steel blades of the drill rod discharge coal and rock debris generated during drilling through the spiral steel blades. The rotatable balls embedded in the spiral steel blades reduce drilling resistance, improve efficiency, reduce drill rod wear, and decrease frictional heat. This improves the service life of the drill rod, drilling efficiency, and construction safety.

[0024] Furthermore, when the mounting slot is connected to the high-pressure medium channel inside the drill pipe body, a small amount of high-pressure medium inside the drill pipe body will enter the mounting slot through the high-pressure medium channel. This prevents the balls from shaking within the mounting slot and also prevents fine drill cuttings from entering the gap between the mounting slot and the balls, ensuring the balls can roll continuously and avoid jamming. Simultaneously, a small amount of high-pressure perforation medium overflowing from the gap between the mounting slot and the balls plays a role in gas control. If the high-pressure perforation medium is high-pressure water, it not only cools the gas but also dilutes it, thus preventing gas explosions; if the high-pressure perforation medium is high-pressure air, it efficiently dilutes the gas. Attached Figure Description

[0025] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the overall structure of the present invention;

[0027] Figure 2 for Figure 1 A sectional view;

[0028] Figure 3 for Figure 1 The left view;

[0029] Figure 4 for Figure 1 The right view;

[0030] Figure 5 This is a schematic diagram illustrating the application state of the present invention;

[0031] Figure 6 This is a schematic diagram of the overall drilling tool connection of the present invention.

[0032] In the diagram: 1-external thread structure of drill pipe, 2-ball bearing, 3-spiral steel sheet, 4-drill pipe body, 5-internal thread structure of drill pipe, 6-drill bit. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] A wear-resistant, active resistance-reducing drill pipe for underground coal mines, such as Figure 1and Figure 2 As shown, the system includes a drill rod body 4, with spiral steel plates 3 arranged around the outer wall of the drill rod body 4 along its length. The height of the spiral steel plates 3 is moderate, neither too high nor too low. If the spiral steel plates 3 are too high, they will cut into the coal wall, resulting in increased cutting volume and increased resistance; if the height of the spiral steel plates 3 is too low, the slag removal effect will be weakened.

[0035] The spiral steel plate 3 is rotatably mounted on the side wall away from the drill rod body 4, with some balls 2 located inside the spiral steel plate 3 and others outside. The balls, rolling on the outer contour surface of the spiral steel plate 3, can rotate freely but cannot move. When the balls contact the coal wall, rolling friction is generated, transforming the original sliding friction between the drill rod outer wall and the coal wall into rolling friction. This effectively reduces frictional resistance and consequently lowers the heat generated. This reduces the risk of coal and gas disasters during drilling, providing safety assurance for the drilling process.

[0036] In a preferred embodiment, the spiral steel sheet 3 is provided with a mounting groove, and part of the ball bearing 2 is disposed within the mounting groove, while another part protrudes from the mounting groove. During assembly, the ball bearing is first placed in the mounting groove, and then a positioning plate is placed between the ball bearing 2 and the mounting groove. The positioning plate is clearance-fitted with the ball bearing 2 to prevent the ball bearing 2 from falling out of the mounting groove. When the ball bearing 2 comes into contact with the hole wall or drill cuttings, the ball bearing 2 rotates within the mounting groove. The ball bearing 2 is preferably made of steel.

[0037] In another preferred embodiment, an installation groove is provided on the spiral steel sheet 3. The installation groove has a frustum-shaped structure, and the outer groove opening at the outer edge of the spiral steel sheet 3 is smaller than the inner groove opening at the drill rod body 4. The diameter of the outer groove opening is smaller than the diameter of the ball bearing 2. During assembly, the ball bearing 2 is first installed in the installation groove, and then the spiral steel sheet 3 is welded to the outer wall of the drill rod body 4 section by section.

[0038] In a preferred embodiment, the mounting groove is connected to the high-pressure medium channel inside the drill rod body 4. A small amount of high-pressure medium inside the drill rod body 4 will enter the mounting groove through the high-pressure medium channel. This prevents the ball bearings 2 from shaking within the mounting groove and prevents fine drill cuttings from entering the gap between the mounting groove and the ball bearings 2, ensuring the ball bearings 2 can roll continuously without jamming. Furthermore, a small amount of high-pressure perforating medium overflowing from the gap between the mounting groove and the ball bearings 2 will play a role in gas control. If the high-pressure perforating medium is high-pressure water, it will not only cool the gas but also dilute it, thus preventing gas explosions. If the high-pressure perforating medium is high-pressure air, it will efficiently dilute the gas.

[0039] Furthermore, the working of the ball 2 is assisted by adjusting the pressure of the medium in the high-pressure medium channel. As the ball 2 wears, the medium pressure gradually increases, so that the ball can always be sealed at the mounting slot, which can not only prevent drill cuttings from entering, but also ensure that the ball 2 is always in a rolling state.

[0040] In a preferred embodiment, the ball bearings 2 are arranged at equal intervals along the extending direction of the spiral steel sheet 3. For example... Figure 3 and Figure 4 As shown, the outer diameter of the drill rod is wrapped with a ring of balls 2. When the balls 2 come into contact with the coal wall, the balls 2 and the coal wall form rolling friction, which transforms the original sliding friction between the outer wall of the drill rod and the coal wall into rolling friction, effectively reducing frictional resistance and thus reducing the heat generated.

[0041] Furthermore, such as Figure 2 As shown, the cross-section of the spiral steel sheet 3 is trapezoidal, and the pitch of the spiral steel sheet 3 is the same along the length of the drill rod body 4. During drilling, the slag from the drill bit 6 accumulates around the drill rod. As the borehole moves inward, the resistance between the drill cuttings and the drill rod 6 increases. Therefore, this invention can utilize the friction between the sidewall of the spiral steel sheet 3 and the drill cuttings to discharge the slag from the borehole. The design of the spiral steel sheet and the structural design with the same pitch effectively solve the problems of drill cuttings accumulation and increased resistance.

[0042] In a preferred embodiment, one end of the drill rod body 4 is provided with an external thread structure 1, and the other end is provided with an internal thread structure 5. The drill bit 6 is connected to the drill rod body 4 through the internal thread structure 5. Adjacent drill rod bodies 4 are connected by mutually cooperating external thread structures 1 and internal thread structures 5. The main movement of the underground hydraulic drilling rig is rotation. By rotating the drilling rig, the drill rod is connected to the drill bit, and the drill rods are connected to each other. This provides high-strength preload, ensuring safety during the drilling process and preventing drill bit detachment.

[0043] Furthermore, the outline of the drill pipe external thread structure 1 is frustum-shaped.

[0044] In a preferred embodiment, the diameter of the drill bit 6 is larger than the diameter of the drill rod body 4, and the vertical distance between the outer peripheral surface of the spiral steel sheet 3 and the outer peripheral surface of the drill rod body 4 is smaller than the vertical distance between the outer peripheral surface of the drill bit 6 and the outer peripheral surface of the drill rod body 4.

[0045] A method for using a wear-resistant active resistance-reducing drill pipe for underground coal mines, comprising the wear-resistant active resistance-reducing drill pipe for underground coal mines as described above, the method comprising the following steps:

[0046] Step 1: During the process, first fix the drilling rig in the predetermined position and adjust the angle. Select the required drill bit size (e.g., 6mm) according to the borehole diameter.Figure 6 As shown, the rotating rod body 4 is connected to the drill bit 6 through the drill rod external thread structure 1. At the same time, it is required that the outer diameter of the drill bit 6 is slightly larger than the overall outer diameter of the wear-resistant active resistance-reducing drill rod used in underground coal mines.

[0047] Step 2: Clamp the end of the wear-resistant active resistance-reducing drill rod for underground coal mines with the drill rig holder, turn on the drill rig to start rotating at a constant speed and drill into the coal wall at a predetermined angle;

[0048] Step 3: When the borehole is deep and a large number of drill rods are required, after one coal mine wear-resistant active resistance-reducing drill rod is drilled into the coal seam, a new coal mine wear-resistant active resistance-reducing drill rod is connected to the tail of the drill rod after it has entered the coal seam to extend the total length of the drill rod.

[0049] Step 4: When extending the total length of the drill pipe, such as... Figure 6 As shown, the internal thread structure 5 at the tail of the preceding wear-resistant active resistance-reducing drill rod for underground coal mines is tightened with the external thread structure 1 at the end of the following wear-resistant active resistance-reducing drill rod for underground coal mines. The tightening direction is opposite to the rotation direction of the drilling rig. As the drill continues to extend into the borehole, steps three and four are repeated, connecting the drill rods in sequence. Once the predetermined depth is reached, the drill rods and drill bits are pulled out, and the drilling ends.

[0050] Furthermore, both the spiral steel sheet 3 and the drill rod body 4 are prefabricated structures, with the spiral steel sheet 3 welded onto the outer wall of the drill rod body 4; during drilling, if... Figure 5 As shown, the spiral steel sheet 3 provides protection for the drill rod body 4, while the coal slag from the drill bit 6 accumulates around the drill rod body 4. As the borehole deepens, the resistance between the drill cuttings and the wear-resistant active resistance-reducing drill rod used in underground coal mines gradually increases. The friction between the sidewall of the spiral steel sheet 3 and the drill cuttings discharges the drill cuttings from the borehole. During the drilling process, when the ball bearing 2 comes into contact with the borehole wall or drill cuttings, the ball bearing 2 forms rolling friction with the borehole wall or drill cuttings. By reducing frictional resistance, heat generation is reduced, thereby reducing the risk of coal and gas disasters during the drilling process and providing safety assurance for the drilling process.

[0051] All aspects not detailed in this invention are conventional technical means known to those skilled in the art.

[0052] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A mine wear-resistant active drag-reducing drill pipe for underground coal mines, comprising a drill pipe body (4), characterized in that: Spiral steel sheet (3) is arranged on the outer wall of the drill rod body (4), the spiral steel sheet (3) is arranged along the length direction of the drill rod body (4), the spiral steel sheet (3) is rotationally arranged with a ball (2) on the side wall away from the drill rod body (4), the ball (2) is a steel ball, a part of the ball (2) is located in the spiral steel sheet (3), and the other part is located outside the spiral steel sheet (3); The spiral steel sheet (3) is provided with a mounting groove, a part of the ball (2) is arranged in the mounting groove, and the other part protrudes from the mounting groove, a positioning plate is arranged between the ball (2) and the mounting groove, and the ball (2) rotates in the mounting groove when the ball (2) contacts the hole wall or the drill cuttings; The mounting groove is communicated with the high-pressure medium channel inside the drill rod body (4), the pressure of the medium in the high-pressure medium channel is adjusted to assist the ball (2) to work, the medium pressure is gradually increased with the wear of the ball (2), the ball (2) always seals the mounting groove, and the ball (3) is always in a rolling state; The cross section of the spiral steel sheet (3) is trapezoidal, and the pitch of the spiral steel sheet (3) along the length direction of the drill rod body (4) is the same; One end of the drill rod body (4) is provided with a drill rod external thread structure (1), the other end is provided with a drill rod internal thread structure (5), a drill bit (6) is connected with the drill rod body (4) through the drill rod internal thread structure (5), and adjacent drill rod bodies (4) are connected through the drill rod external thread structure (1) and the drill rod internal thread structure (5) matched with each other; The diameter of the drill bit (6) is greater than the diameter of the drill rod body (4), and the vertical distance between the outer periphery of the spiral steel sheet (3) and the outer periphery of the drill rod body (4) is less than the vertical distance between the outer periphery of the drill bit (6) and the outer periphery of the drill rod body (4).

2. The coal mine underground wear-resistant proactive drag-reducing drill pipe of claim 1, wherein: Or a mounting through groove is arranged on the spiral steel sheet (3), the mounting through groove is a circular truncated cone structure, the outer groove opening of the mounting through groove at the outer edge of the spiral steel sheet (3) is smaller than the inner groove opening at the position abutting the drill rod body (4), the diameter of the outer groove opening is smaller than the diameter of the ball (2), and a ball support seat is arranged between the outer groove opening and the drill rod body (4).

3. The coal mine underground wear-resistant proactive drag-reducing drill pipe of claim 2, wherein: The mounting through groove is communicated with the high-pressure medium channel inside the drill rod body (4).

4. The abrasion resistant, proactive drag-reducing drill pipe for underground mining as claimed in any one of claims 1 to 3, characterized in that: The ball (2) is arranged at equal intervals along the extension direction of the spiral steel sheet (3).

5. The abrasion resistant, active drag reducing drill pipe for underground mining as claimed in claim 4, wherein: The profile of the drill rod external thread structure (1) is a circular truncated cone.

6. A method of using a coal mine downhole wear-resistant active drag-reducing drill pipe, characterized in that, The coal mine underground mine wear-resistant active resistance-reducing drill rod comprises the drill rod body (4), the spiral steel sheet (3) and the ball (2), and the coal mine underground mine wear-resistant active resistance-reducing drill rod uses the method comprising the following steps: Step one: during implementation, first fix the drilling machine at a predetermined position and adjust the angle, select a drill bit (6) of a required size according to the drilling diameter, connect the drill bit (6) with the drill rod body (4) through the drill rod external thread structure (1), and require that the outer diameter of the drill bit (6) is slightly larger than the overall outer diameter of the coal mine underground mine wear-resistant active resistance-reducing drill rod; Step two: clamp the tail end of the coal mine underground mine wear-resistant active resistance-reducing drill rod through the drilling machine gripper, turn on the drilling machine to start uniform rotation, and drill into the coal wall at a predetermined angle. Step three: when the drilling is deep and the number of drill pipes is large, a coal mine underground mine wear-resistant active drag-reducing drill pipe is drilled into the coal seam, and a new coal mine underground mine wear-resistant active drag-reducing drill pipe is connected at the tail of the coal mine underground mine wear-resistant active drag-reducing drill pipe drilled into the coal seam, to extend the total length of the drill pipe; Step four: when the total length of the drill pipe is extended, the drill pipe internal thread structure (5) at the tail of the previous coal mine underground mine wear-resistant active drag-reducing drill pipe is screwed with the drill pipe external thread structure (1) at the end of the next coal mine underground mine wear-resistant active drag-reducing drill pipe, the screwing direction is opposite to the rotation direction of the drilling machine, and the drilling machine continues to extend into the inside of the drill hole, steps three and four are repeated, the drill pipes are connected in turn, the drill pipe and the drill bit are pulled out to the predetermined depth, and the drilling is completed.

7. The method for using the wear-resistant, active drag-reducing drill pipe for underground coal mining as claimed in claim 6, characterized in that: The spiral steel sheet (3) and the drill pipe body (4) are both prefabricated structures, the spiral steel sheet (3) is arranged on the outer wall of the drill pipe body (4) by welding, in the drilling process, the spiral steel sheet (3) provides protection for the drill pipe body (4), at the same time, the drill bit (6) drills holes and cuts coal residues, which accumulate around the drill pipe body (4), as the drilling goes deeper, the resistance between the drill cuttings and the coal mine underground mine wear-resistant active drag-reducing drill pipe gradually increases, the side wall of the spiral steel sheet (3) and the drill cuttings rub to remove the drill cuttings from the drill hole; In the drilling process, when the ball (2) contacts the hole wall or the drill cuttings, the ball (2) and the hole wall or the drill cuttings form rolling friction, and the heat generation is reduced by reducing the friction resistance.

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