Coal face drilling device and method

Abstract

The invention relates to the field of drilling, in particular to a coal face drilling device and method.The lower end of a drill rod is fixedly provided with a drill bit, the drill bit is internally provided with a high-pressure water chamber, the outer wall of the drill bit is provided with injection holes communicating with the bottom of the high-pressure water chamber, the drill rod is internally provided with a liquid inlet channel, and a vertically-extending transmission shaft is rotationally installed in the high-pressure water chamber; a water wheel is fixedly installed at the upper end of the transmission shaft, a movable column is vertically and slidably installed on the bottom wall of the driving cavity, the lower end of the movable column extends out of the drill bit and is provided with a hammer head, a transmission component connected with the transmission shaft and the movable column is arranged in the driving cavity, and the transmission shaft drives the movable column to vertically reciprocate through the transmission component when rotating; when the drill bit drills, high-pressure water is injected into the high-pressure water chamber through the liquid inlet channel, the water wheel is impacted by the high-pressure water and drives the transmission shaft to rotate, the curve groove in the cylindrical cam acts on the sliding pin and drives the sleeve to vertically move in a reciprocating mode, and the sleeve drives the hammer head to vertically move in a reciprocating mode through the movable column to continuously impact a coal seam.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of drilling devices, in particular to a coal mining face drilling device and method. BACKGROUND

[0002] The Coal Mine Safety Regulations, Coal Mine Gas Extraction Basic Indexes and other regulations clearly stipulate that after pre-extraction of coal seam gas, the effect of pre-extraction gas prevention and control of outburst must be inspected, one of the inspection indexes is that the coal seam gas pre-extraction rate is greater than 30%, that is, the gas content after extraction is less than 30% of the gas content before extraction, at the same time, it meets the requirements of the Regulations on Prevention and Control of Coal and Gas Outburst, and is reduced to 5.0 m 3 / t or less.

[0003] The effective extraction radius of the borehole refers to the effective distance of the coal bed methane that can be extracted from the borehole within a certain time, which is mainly used to measure the actual influence range of the borehole on the surrounding coal bed methane resources. Under the premise of ensuring the allowable error of industrial application, the gas pressure P and the gas content X have a certain relationship, therefore, the proportion of the decrease of the gas content before and after extraction and the proportion of the decrease of the gas pressure are in a parabolic relationship; if the coal seam pre-extraction rate is 30%, that is, the residual gas content is 70% of the original gas, through calculation, it is known that the residual gas pressure is 49% of the original gas pressure value, and the gas pressure decreases by 51%. The effective radius of the borehole measured by the relative pressure index method is based on this principle.

[0004] In the prior art, there are various drilling construction equipment, such as the drilling construction equipment and coal seam gas extraction method disclosed in the invention patent with the application number CN202510901457.8, which can only drill through the end drill rod driven by the drilling machine or impact and crack through the impact drill bit driven by the drilling machine, and cannot realize the simultaneous working of the end drill rod drilling and the impact drill bit impact and cracking, the switching between the two working states is relatively inconvenient, thereby reducing the drilling efficiency. SUMMARY

[0005] The purpose of the present application is to provide a coal mining face drilling device and method, which can drill through the drill bit while impacting the coal seam through the hammer head reciprocating, so as to solve the defects in the background art.

[0006] To achieve the above purpose, the present application provides the following technical solutions: A drilling device for coal mining faces includes a drill rod, a drill bit fixedly mounted at the lower end of the drill rod, a high-pressure water chamber inside the drill bit, and a jetting hole on the outer wall of the drill bit communicating with the bottom of the high-pressure water chamber. A liquid inlet channel is provided inside the drill rod, extending downwards from its upper end to the top of the high-pressure water chamber, with the upper end of the liquid inlet channel connected to a high-pressure water source. A vertically extending drive shaft is rotatably mounted inside the high-pressure water chamber, and a water wheel is fixedly mounted at the upper end of the drive shaft. A drive chamber is provided inside the drill bit located below the high-pressure water chamber, with the lower end of the drive shaft extending into the drive chamber. A movable column is vertically slidably mounted on the bottom wall of the drive chamber, with its lower end extending out of the drill bit and fitted with a hammer. A transmission component connecting the drive shaft and the movable column is provided inside the drive chamber. When the drive shaft rotates, the transmission component drives the movable column to reciprocate vertically.

[0007] As a further improvement, the transmission component includes a cylindrical cam coaxially fixedly mounted on the lower end of the transmission shaft. A curved groove is provided around the outer circumference of the cylindrical cam. A sleeve located in the drive cavity is fixedly mounted on the upper end of the movable column. The sleeve is sleeved on the outer side of the cylindrical cam. A sliding pin matching the curved groove is fixedly mounted on the inner wall of the sleeve.

[0008] As a further improvement, the curved groove is a closed wave shape surrounding the cylindrical cam.

[0009] As a further improvement, the bottom of the drill bit is provided with a groove to accommodate the hammer head.

[0010] As a further improvement, the top wall of the groove is provided with a guide hole that vertically connects to the bottom wall of the drive cavity, and the movable column is vertically slidably installed in the guide hole.

[0011] As a further improvement, the movable column is in the shape of a polygonal prism, and the shape of the guide hole matches the cross-sectional shape of the movable column.

[0012] As a further improvement, the hammer head is provided with a mounting cavity, and the top wall of the mounting cavity is provided with a through hole that penetrates the hammer head upward. The lower end of the movable column is vertically slidably installed in the through hole, and a baffle located in the mounting cavity is fixedly installed at the lower end of the movable column. A spring is connected between the baffle and the bottom wall of the mounting cavity.

[0013] A drilling method using the aforementioned coal mining face drilling device, the method comprising the following steps: S1, connect the upper end of the drill rod to the drilling machine, and drive the drill bit to rotate and drill through the drilling machine; S2, during the process of the drill bit drilling into the coal seam, high-pressure water is injected into the high-pressure water chamber. The water wheel is impacted by the high-pressure water and drives the drive shaft to rotate. The drive shaft drives the hammer head to reciprocate vertically through the movable column to impact the coal seam.

[0014] Compared with the prior art, the beneficial effects of the present invention are: 1. While the drill bit is drilling, high-pressure water is injected into the high-pressure water chamber through the fluid inlet channel. The water wheel is impacted by the high-pressure water and drives the drive shaft to rotate. The drive shaft drives the cylindrical cam to rotate. The curved groove on the cylindrical cam acts on the sliding pin and drives the sleeve to move vertically back and forth. The sleeve drives the hammer head to move vertically back and forth through the movable column to continuously impact the coal seam. Thus, while the drill bit is drilling, the hammer head impacts the coal seam, thereby improving drilling efficiency. 2. A spring is connected between the baffle and the bottom wall of the mounting cavity. When the hammer impacts the coal seam downwards, the spring can act as a buffer, thereby reducing the impact force transmitted to the movable column and improving its service life. Attached Figure Description

[0015] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the 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.

[0016] Figure 1 This is a schematic diagram of the structure of an embodiment of the present invention; Figure 2 This is a schematic diagram of the drill bit structure according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the cylindrical cam according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the hammer head structure according to an embodiment of the present invention.

[0017] In the diagram: 1-Drill rod; 2-Drill bit; 3-High-pressure water chamber; 4-Mounting base; 5-Jet hole; 6-Liquid inlet channel; 7-Drive shaft; 8-Water wheel; 9-Drive cavity; 10-Moving column; 11-Cylindrical cam; 12-Curved groove; 13-Sleeve; 14-Sliding pin; 15-Groove; 16-Guide hole; 17-Mounting cavity; 18-Baffle; 19-Spring; 20-Hammer. Detailed Implementation

[0018] 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 of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0019] like Figures 1 to 4 As shown, a drilling device for a coal mining face includes a drill rod 1. A drill bit 2 is fixedly installed at the lower end of the drill rod 1. A high-pressure water chamber 3 is provided inside the drill bit 2. The high-pressure water chamber 3 is cylindrical. A mounting base 4 is fixedly installed at the upper end of the high-pressure water chamber 3 by bolts. The mounting base 4 has a vertically penetrating mounting hole. The lower end of the drill rod 1 is threaded into the mounting hole. The mounting base 4 and the lower end of the drill rod 1 together seal the top of the high-pressure water chamber 3. Multiple injection holes 5 are evenly distributed on the outer wall of the drill bit 2, connecting to the bottom of the high-pressure water chamber 3. A liquid inlet channel 6 is provided inside the drill rod 1, connecting downwards from its upper end to the top of the high-pressure water chamber 3. The upper end of the liquid inlet channel 6 is connected to a high-pressure water source. High-pressure water is injected into the high-pressure water chamber 3 through the liquid inlet channel 6. Subsequently, the high-pressure water is sprayed out through the injection holes 5 on the outer wall of the drill bit 2. On the one hand, it cools the drill bit 2, and on the other hand, it flushes the hole wall with high-pressure water during the drilling process to prevent the drill from getting stuck.

[0020] A vertically extending drive shaft 7 is rotatably mounted on the center of the bottom wall of the high-pressure water chamber 3 via a bearing. A water wheel 8 is fixed to the upper end of the drive shaft 7 with bolts. A drive chamber 9 is provided inside the drill bit 2 located below the high-pressure water chamber 3, and the lower end of the drive shaft 7 extends into the drive chamber 9. High-pressure water enters the high-pressure water chamber 3 through the inlet channel 6 and is discharged from multiple jet holes 5. During this process, the water wheel 8 is impacted by the high-pressure water and drives the drive shaft 7 to rotate inside the drill bit 2.

[0021] A movable column 10 is vertically slidably mounted on the bottom wall of the drive cavity 9. The lower end of the movable column 10 extends out of the drill bit 2 and is equipped with a hammer head 20. The drive cavity 9 is provided with a transmission component that connects the drive shaft 7 and the movable column 10. When the drive shaft 7 rotates, it drives the movable column 10 to move vertically back and forth through the transmission component.

[0022] like Figure 2 As shown, the transmission component includes a cylindrical cam 11 coaxially fixed to the lower end of the transmission shaft 7 by bolts. A curved groove 12 is provided around the outer circumference of the cylindrical cam 11. A sleeve 13 located in the drive cavity 9 is fixed to the upper end of the movable column 10 by bolts. The sleeve 13 is sleeved on the outer side of the cylindrical cam 11. A sliding pin 14 matching the curved groove 12 is embedded on the inner wall of the sleeve 13. The sliding pin 14 extends radially along the cylindrical cam 11, and one end of the sliding pin 14 is slidably installed in the curved groove 12.

[0023] like Figure 3As shown, the curved groove 12 is a closed wave shape surrounding the cylindrical cam 11. After being impacted by high-pressure water, the water turbine 8 drives the cylindrical cam 11 to rotate through the transmission shaft 7. Consequently, the curved groove 12 on the cylindrical cam 11 acts on the sliding pin 14 and drives the sleeve 13 to move vertically back and forth. Then, the sleeve 13 drives the hammer head 20 to move vertically back and forth through the movable column 10 to continuously impact the coal seam.

[0024] like Figure 2 As shown, the bottom of the drill bit 2 is provided with a groove 15 to accommodate the hammer head 20. Specifically, when the hammer head 20 rises to its highest point, it retracts into the groove 15; when the hammer head 20 descends to its lowest point, its lower end extends out of the groove 15 and impacts the coal seam. The bottom of the hammer head 20 may be a convex hemispherical shape or a conical shape.

[0025] The top wall of the groove 15 is provided with a guide hole 16 that vertically connects to the bottom wall of the drive cavity 9, and the movable column 10 is vertically slidably installed in the guide hole 16. Moreover, the movable column 10 is in the shape of a polygonal prism, and the shape of the guide hole 16 matches the cross-sectional shape of the movable column 10, which can prevent the sleeve 13 and the movable column 10 from rotating with the cylindrical cam 11.

[0026] like Figure 4 As shown, the hammer head 20 has an installation cavity 17. The top wall of the installation cavity 17 has a through hole that penetrates the hammer head 20 upwards. The lower end of the movable column 10 is vertically slidably installed in the through hole. The lower end of the movable column 10 is fixedly installed with a baffle 18 located in the installation cavity 17 by bolts, which can prevent the hammer head 20 from falling off the lower end of the movable column 10. A spring 19 is connected between the baffle 18 and the bottom wall of the installation cavity 17. When the hammer head 20 impacts the coal seam downwards, the spring 19 can play a buffering role, thereby reducing the impact force transmitted to the movable column 10 and improving its service life.

[0027] A drilling method using a drilling device in a coal mining face, the method comprising the following steps: S1, connect the upper end of drill rod 1 to the drilling machine, and drive drill bit 2 to rotate and drill through the drilling machine; S2, during the process of drill bit 2 drilling into the coal seam, high-pressure water is injected into high-pressure water chamber 3. Water wheel 8 is impacted by high-pressure water and drives transmission shaft 7 to rotate. Transmission shaft 7 drives cylindrical cam 11 to rotate. Curved groove 12 on cylindrical cam 11 acts on sliding pin 14 and drives sleeve 13 to move vertically back and forth. Sleeve 13 drives hammer head 20 to move vertically back and forth through movable column 10 to continuously impact coal seam.

[0028] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely preferred examples and are not intended to limit the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of the present invention is defined by the appended claims and their equivalents.

Claims

1. A drilling device for coal mining faces, characterized in that: The system includes a drill rod (1), a drill bit (2) fixedly mounted at the lower end of the drill rod (1), a high-pressure water chamber (3) inside the drill bit (2), an injection hole (5) on the outer wall of the drill bit (2) connecting to the bottom of the high-pressure water chamber (3), a liquid inlet channel (6) inside the drill rod (1) connecting downwards to the top of the high-pressure water chamber (3), and a high-pressure water source connected to the upper end of the liquid inlet channel (6); a vertically extending drive shaft (7) is rotatably mounted inside the high-pressure water chamber (3), and a water wheel (8) is fixedly mounted at the upper end of the drive shaft (7). The drill bit (2) located below the high-pressure water chamber (3) is provided with a drive chamber (9). The lower end of the drive shaft (7) extends into the drive chamber (9). A movable column (10) is vertically slidably installed on the bottom wall of the drive chamber (9). The lower end of the movable column (10) extends out of the drill bit (2) and is equipped with a hammer (20). The drive chamber (9) is provided with a transmission component that connects the drive shaft (7) and the movable column (10). When the drive shaft (7) rotates, it drives the movable column (10) to move vertically back and forth through the transmission component.

2. The drilling device for a coal mining face as described in claim 1, characterized in that: The transmission component includes a cylindrical cam (11) coaxially fixedly mounted on the lower end of the transmission shaft (7). A curved groove (12) is provided around the outer circumference of the cylindrical cam (11). A sleeve (13) located in the drive cavity (9) is fixedly mounted on the upper end of the movable column (10). The sleeve (13) is sleeved on the outer side of the cylindrical cam (11). A sliding pin (14) matching the curved groove (12) is fixedly mounted on the inner wall of the sleeve (13).

3. The drilling device for a coal mining face as described in claim 2, characterized in that: The curved groove (12) is a closed wave shape surrounding the cylindrical cam (11).

4. The drilling device for a coal mining face as described in claim 1, characterized in that: The bottom of the drill bit (2) is provided with a groove (15) for accommodating the hammer (20).

5. The drilling device for a coal mining face as described in claim 4, characterized in that: The top wall of the groove (15) is provided with a guide hole (16) that is vertically connected to the bottom wall of the drive cavity (9), and the movable column (10) is vertically slidably installed in the guide hole (16).

6. The drilling device for a coal mining face as described in claim 5, characterized in that: The movable column (10) is in the shape of a polygonal prism, and the shape of the guide hole (16) matches the cross-sectional shape of the movable column (10).

7. The drilling device for a coal mining face as described in claim 1, characterized in that: The hammer head (20) is provided with a mounting cavity (17). The top wall of the mounting cavity (17) is provided with a through hole that penetrates the hammer head (20) upwards. The lower end of the movable column (10) is vertically slidably installed in the through hole. The lower end of the movable column (10) is fixedly installed with a baffle (18) located in the mounting cavity (17). A spring (19) is connected between the baffle (18) and the bottom wall of the mounting cavity (17).

8. A drilling method using the drilling device for a coal mining face according to any one of claims 1-7, characterized in that, The method includes the following steps: S1, connect the upper end of the drill rod (1) to the drilling machine, and drive the drill bit (2) to rotate and drill through the drilling machine; S2, during the process of the drill bit (2) drilling into the coal seam, high-pressure water is injected into the high-pressure water chamber (3). The water wheel (8) is impacted by the high-pressure water and drives the transmission shaft (7) to rotate. The transmission shaft (7) drives the hammer (20) to reciprocate vertically to impact the coal seam through the movable column (10).

Images