Method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission

Abstract

The invention relates to a method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission, comprising the following steps: S1: assembling a construction device at the position of an extraction borehole, adjusting the height and horizontal position of a spiral drill rod; S2: starting a drilling rig and simultaneously starting a hydraulic pump station; S3: after drilling until the spiral drill rod is almost completely entered into the borehole, shutting down the drilling rig, removing the connection between the spiral drill rod and a power output shaft, adding a new spiral drill rod, and then starting the drilling rig again for drilling; repeating steps S2 to S3 until drilling to a designed depth, shutting down the drilling rig, and withdrawing the spiral drill rod and a drill bit; S4: after the gas extraction drilling construction is completed, immediately connecting the drilling rig with a gas extraction pipeline in a coal mine to implement a gas extraction operation; S5: then adjusting the horizontal position of the power output shaft to move it to the designed position of the next borehole, and repeating steps S1 to S4 until all dense parallel drilling constructions along the coal seam strike direction of the mining working face are completed.

Description

Technical Field

[0001] The invention belongs to the technical field of coal mine safety, and relates to a method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission. Background Art

[0002] Gas is one of the main threats to mine safety. It is a combustible gas with methane as the main component, which exists in coal seams or surrounding rocks in adsorbed and free forms. my country mainly adopts coal seam extraction to implement mine gas disaster management, which is to drill holes in the coal seam through a drilling rig, and then connect the boreholes to the gas extraction pipelines under the coal mine, so that the gas in the coal seam enters the gas extraction pipeline through the boreholes, and then is extracted by the gas extraction pump station installed on the ground.

[0003] With the development of science and technology, advanced high-power directional drilling technology has been widely used in my country's coal mines. However, due to the complex geological conditions of coal seam gas in my country, most mines in the southwest region do not actually have the conditions for the application of high-power directional drilling technology. Therefore, the traditional method of arranging dense parallel boreholes along the strike direction of the coal seam is still used. In this case, the position of the drilling rig needs to be moved immediately after the drilling is completed, so this type of drilling arrangement actually increases the labor intensity of moving the drilling rig.

[0004] In addition, the conditions of thick and extra-thick coal seams in some mining areas in my country are suitable for long-distance directional drilling. However, due to the large thickness of the coal seams and the presence of interlayers in the coal seams, the extraction effect of simple long-distance directional drilling is poor, and most of them have different degrees of extraction blind spots. Therefore, most of these mines still use drilling rigs to construct dense parallel drilling holes in the thick and extra-thick coal seams. Similarly, the gas control projects in this case also have the problem of high frequency of drilling rig movement.

[0005] In summary, for mines with complex coal seam gas storage conditions, developing a drilling construction process suitable for such geological conditions and with low movement frequency, and further carrying out mine gas extraction operations are one of the key technical issues that need to be urgently solved in the field of coal mine safety in my country. In addition, in view of the common extraction blind area problem in thick and extra-thick coal seams with interbedded gangue, studying the drilling arrangement form suitable for such conditions and proposing the corresponding advanced drilling technology is also another technical problem that coal mine safety workers need to solve. Summary of the invention

[0006] In view of this, the object of the present invention is to provide a method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission that can solve the above problems.

[0007] In order to achieve the above object, the present invention provides the following technical solutions:

[0008] The method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission includes the following steps:

[0009] S1: At the location of the gas extraction drilling hole to be constructed, the construction device is assembled, the construction device includes a power input shaft located on the support frame 1, the power input shaft is connected to the power output shaft through a transmission structure, the power output shaft is fixedly connected to the tail of the spiral drill rod, the head of the spiral drill rod is fixedly connected to the drill bit, the position of the power output shaft can be adjusted in the horizontal direction and the vertical direction to meet the dense drilling of different heights and positions, and then the clamping device of the drilling rig is connected to the power input shaft; the height and horizontal position of the spiral drill rod are adjusted so that the position parameters of the drilling hole meet the design requirements;

[0010] S2: The drilling rig is turned on, and the drilling rig transmits the rotational motion to the power input shaft. The auger rod drives the drill bit to work, and at the same time the hydraulic pump station is turned on. The power input shaft and the power output shaft can move toward the borehole driven by the hydraulic pump station. The auger rod and the drill bit gradually enter the coal body during the rotation process.

[0011] S3: After the auger rod is almost completely inserted into the borehole, the drilling rig is turned off and the hydraulic pump station is turned on to move the power input shaft and the power output shaft, the auger rod and the drill bit toward the borehole opening as a whole, and then the connection between the auger rod and the power output shaft is removed, and a new auger rod is added, and the drilling rig is turned on again for drilling; steps S2 to S3 are repeated until the drilling reaches the designed depth, and then the drilling rig can be turned off and the auger rod and the drill bit are withdrawn;

[0012] S4: After the gas extraction drilling is completed, it is immediately connected to the gas extraction pipeline in the coal mine to carry out gas extraction operations;

[0013] S5: Then, adjust the horizontal position of the power output shaft to move it to the designed position of the next drill hole, and repeat S1 to S4 until all dense parallel drill holes along the direction of the coal seam of the mining face are completed.

[0014] Furthermore, the method further includes the step: S6, when the coal seam is thick or extra thick, annular distribution boreholes are designed in an annular distribution form to implement coal seam gas extraction.

[0015] Furthermore, in step S6, all the gas extraction holes of the annularly distributed boreholes that need to be constructed in the mining face are regarded as 5 layers of dense parallel boreholes; during construction, steps S1 to S5 are implemented, and after each layer of dense parallel boreholes is completed, the height of the power output shaft is adjusted, and the next layer of dense parallel boreholes is constructed again.

[0016] Furthermore, a positioning slider is provided on the power output shaft, and the power output shaft is arranged at the lower part of the positioning slider. The power output shaft passes through the positioning slider and is connected with the positioning slider through a bearing. A horizontal transmission hole is opened on the upper part of the positioning slider, and the axis of the transmission hole is perpendicular to the axis of the power output shaft. The screw rod passes through the transmission hole, and the screw rod is threadedly matched with the transmission hole. A parallel moving track of the positioning slider is provided below the screw rod.

[0017] Furthermore, both ends of the screw rod are respectively fixed on the support frame 2 through the bearing fixing seat 2, and the support frame 2 is located on the hydraulic lifting platform 2. The support frame 2 can reciprocate in the drilling direction on the hydraulic lifting platform 2. In step S5, the height adjustment of the power output shaft is achieved by adjusting the hydraulic lifting platform 2.

[0018] Furthermore, the support frame 2 is connected to the hydraulic lifting platform 2 through a slide rail, and the support frame 2 is connected to the hydraulic pump station. The hydraulic pump station provides power for the support frame 2, and the height adjustment of the power output shaft is achieved by adjusting the hydraulic lifting platform 2.

[0019] Furthermore, a pair of limit rods are symmetrically fixed to the side of the second bearing fixing seat below the screw rod. The limit rods are located above the power output shaft, and the positioning slider is located between the two limit rods. The space between the two limit rods is a parallel moving track.

[0020] Furthermore, an adjustment handle is fixed at one end of the screw rod. In step S5, the adjustment handle is shaken to move the positioning slider in the axial direction of the screw rod. After the power output shaft moves to the designed position of the next drilling hole, the shaking of the adjustment handle is stopped.

[0021] Furthermore, the transmission structure includes a left-side three-blade rotation transfer blade fixed on the tail end of the power input shaft and a right-side three-blade rotation transfer blade fixed on the front end of the power output shaft. The left-side three-blade rotation transfer blade and the right-side three-blade rotation transfer blade are connected through a movable three-blade rotation transfer blade in the middle. The three blades of the three-blade rotation transfer blade are symmetrically distributed, and a hinge unit is provided at the top of each blade. Hinge units are provided on both sides of the blades on the movable three-blade rotation transfer blade for connecting with the three-blade rotation transfer blade on the corresponding side. The corresponding hinge units between the left-side three-blade rotation transfer blade and the movable three-blade rotation transfer blade, and between the right-side three-blade rotation transfer blade and the movable three-blade rotation transfer blade are respectively connected through connecting rods hinged to them.

[0022] Furthermore, in step S1, support frame 1 is connected to hydraulic lifting platform 1 through a slide rail, support frame 1 is connected to a hydraulic pump station, the hydraulic pump station provides power for support frame 1, and the height adjustment of the power input shaft is achieved by adjusting the hydraulic lifting platform 1.

[0023] The beneficial effects of the present invention are:

[0024] (1) The present invention connects the auxiliary device to the drilling rig through a universal joint, and multiple gas extraction boreholes can be constructed within the maximum travel range of the slider allowed by the screw rod, which greatly reduces the frequency of drilling rig movement and the labor intensity of on-site workers, thus having extremely significant technical benefits;

[0025] (2) The present invention aims to solve the problem of blind areas in extraction in thick and extra-thick coal seams. By adjusting the hydraulic lifting platform, the construction of annularly distributed gas extraction drilling holes can be realized, thereby eliminating the problem of the influence of interlayers in thick and extra-thick coal seams on the gas extraction effect. This can improve the gas extraction effect of the mine, effectively ensure the safe and sustainable supply of coal, and has extremely significant economic benefits.

[0026] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0028] Figure 1 The schematic diagram of the connection structure of the power input shaft and the power output shaft created by the present invention, wherein (a) is a schematic diagram of the structure of the power input shaft on the left, (c) is a schematic diagram of the structure of the power output shaft on the right, (a) and (c) are connected through (b) in the middle;

[0029] Figure 2 A schematic diagram of the connection structure between the positioning slider and the screw rod created by the present invention;

[0030] Figure 3 A schematic diagram of the structure of the drill rod created by the present invention;

[0031] Figure 4 A schematic diagram of the structure of the drilling rig created by the present invention;

[0032] Figure 5 A schematic diagram of the structure of the universal joint created by the present invention;

[0033] Figure 6 A schematic diagram of the structure of dense parallel drilling holes in a common coal seam created by the present invention;

[0034] Figure 7 The mining working face with dense parallel drilling holes created by the present invention;

[0035] Figure 8The drilling hole distribution form of thick and extra-thick coal seams created by the present invention;

[0036] Fig. 9 The invention is a mining working face for thick and extra-thick coal seams.

[0037] Reference numerals:

[0038] 1. Support frame one; 101. Bearing seat one; 2. Power input shaft; 3. Power output shaft; 4. Auger rod; 5. Positioning slide block; 51. Transmission hole; 6. Screw rod; 61. Adjustment handle; 7. Support frame two; 71. Bearing fixing seat; 72. Limit rod; 8. Hydraulic lifting platform two; 9. Three-blade rotary transmission blade on the left; 10. Movable three-blade rotary transmission blade; 11. Three-blade rotary transmission blade on the right; 12. Connecting rod; 13. Drilling rig; 131. Clamping mechanism; 14. Universal transmission joint; 15. Dense parallel drilling; 16. Thick and extra-thick coal seams; 161. Annular distribution drilling; 17. Hydraulic pump station. DETAILED DESCRIPTION

[0039] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0040] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0041] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0042] See also Figures 1 to 9 , is a coal seam intensive drilling construction device based on parallel shaft transmission, including a power input shaft 2 located on a support frame 1, the power input shaft 2 is connected to a power output shaft 3 through a transmission structure, the power output shaft 3 is fixedly connected to the tail of a spiral drill rod 4 through a thread, and the head of the spiral drill rod 4 is fixedly connected to a drill bit through a thread. A rectangular positioning slider 5 is provided on the power output shaft 3, the power output shaft 3 is arranged at the lower part of the positioning slider 5, and the power output shaft 3 passes through the positioning slider 5 and is connected to the positioning slider 5 through a bearing. The power input shaft 2 is fixed to the support frame 1 through a bearing seat 101.

[0043] A horizontal transmission hole 51 is formed on the upper part of the positioning slide block 5. The axis of the transmission hole 51 is perpendicular to the axis of the power output shaft 3. The screw rod 6 passes through the transmission hole 51, and the screw rod 6 is threadedly matched with the transmission hole 51. The two ends of the screw rod 6 are respectively fixed to the support frame 2 7 through the bearing fixing seat 2 71, and the support frame 2 7 is fixed to the hydraulic lifting platform 2 8. A pair of limit rods 72 are symmetrically fixed to the side of the bearing fixing seat 2 71 below the screw rod 6. The limit rod 72 is located above the power output shaft 3. The positioning slide block 5 is located between the two limit rods 72. The space between the two limit rods 72 is the parallel moving track of the positioning slide block 5. The limit rod 72 plays a role of limiting the positioning slide block 5 to prevent the positioning slide block 5 from rotating while the screw rod 6 rotates.

[0044] The support frame 1 is located on the hydraulic lifting platform 1. The support frame 1 and the hydraulic lifting platform 1 are connected by a slide rail. The extension direction of the slide rail is the direction of drilling. The support frame 1 is fixedly connected to the hydraulic pump station 17. The support frame 1 can make reciprocating motion on the slide rail. The hydraulic pump station 17 provides power for the support frame 1.

[0045] The support frame 27 is connected to the hydraulic lifting platform 28 through a slide rail, the extension direction of the slide rail is the direction of drilling, the support frame 27 is fixedly connected to the hydraulic pump station 17, the support frame 27 can do reciprocating motion on the slide rail, and the hydraulic pump station 17 provides power for the support frame 27.

[0046] To facilitate adjustment, an adjustment handle 61 is fixed to one end of the screw rod 6 . Rotating the adjustment handle 61 drives the screw rod 6 to rotate, and the rotation of the screw rod 6 is converted into a linear motion of the positioning slider 5 , so that the position of the positioning slider 5 on the screw rod 6 can be adjusted.

[0047] The tail of the power input shaft 2 is fixedly connected to the tail of the universal joint 14 , and the front end of the universal joint 14 is fixedly connected to the clamping mechanism 131 of the drilling rig 13 .

[0048] The transmission structure includes a left three-blade rotation transfer blade 9 fixed on the tail end of the power input shaft 2 and a right three-blade rotation transfer blade 11 fixed on the front end of the power output shaft 3. The left three-blade rotation transfer blade 9 and the right three-blade rotation transfer blade 11 are connected by a movable three-blade rotation transfer blade 10 in the middle. The three blades of the left three-blade rotation transfer blade 9 and the right three-blade rotation transfer blade 11 are symmetrically distributed, and a hinge unit is provided at the top of each blade; hinge units are provided on the left and right sides of the top of the blade on the movable three-blade rotation transfer blade 10 for connecting with the three-blade rotation transfer blade on the corresponding side, and the corresponding hinge units between the left three-blade rotation transfer blade 9 and the movable three-blade rotation transfer blade 10, and the right three-blade rotation transfer blade 11 and the movable three-blade rotation transfer blade 10 are connected by a connecting rod 12, so that the rotational motion of the power input shaft 2 is transmitted to the power output shaft 3.

[0049] Preferably, the articulated unit is a rotation axis, and the top of the blades of the three-blade rotation transfer blade 9 and the movable three-blade rotation transfer blade 10 are respectively provided with corresponding rotation axes, and the ends of the connecting rod 12 are respectively hinged with the ends of the corresponding blades. Similarly, the top of the blades of the three-blade rotation transfer blade 11 and the movable three-blade rotation transfer blade 10 are respectively provided with corresponding rotation axes, and the ends of the connecting rod 12 are respectively hinged with the ends of the corresponding blades. In this way, when the three-blade rotation transfer blade 9 on the left side rotates, the connecting rod 12 on the left side is driven to swing, the swing of the connecting rod 12 on the left side drives the rotation of the movable three-blade rotation transfer blade 10 in the middle, the rotation of the movable three-blade rotation transfer blade 10 drives the swing of the connecting rod 12 on the right side, and the swing of the connecting rod 12 on the right side drives the rotation of the three-blade rotation transfer blade 11 on the right side, thereby transmitting the power of the power input shaft 2 to the power output shaft 3.

[0050] Power transmission can be achieved through the connecting rods 12 on both sides and the movable three-blade rotating transmission blade 10 in the middle. The connecting rods 12 on both sides and the movable three-blade rotating transmission blade 10 in the middle can make the power output shaft 3 adjust its horizontal position through the adjustment handle 61, and the position of the power input shaft 2 remains unchanged to meet the power transmission.

[0051] The hydraulic lifting platform can adjust the position of the auger head to adapt to different drilling positions.

[0052] The specific implementation method of the present invention is as follows:

[0053] S1: After the auxiliary device is assembled at the location of the gas extraction drilling hole to be constructed, the clamping mechanism 131 of the drilling rig 13 is connected to the plurality of universal joints 14, and then one end of the terminal universal joint 14 is connected to the power input shaft 2; then one end of the auger rod 4 is connected to the power output shaft 3 through a thread; the other end of the auger rod 4 is connected to the drill bit through a thread; then, according to the design requirements of the gas extraction drilling hole, the height of the hydraulic lifting platform is adjusted so that the position parameters of the drilling hole meet the design requirements;

[0054] S2: Then start the drilling rig 13 to drive the universal joint 14 to transmit the rotational motion to the power input shaft 2, and then the power input shaft 2 drives the middle movable three-blade rotational transmission blade 10 through the left three-blade rotational transmission blade 9 arranged thereon, and the movable three-blade rotational transmission blade 10 further drives the right three-blade rotational transmission blade 11 arranged on the power output shaft 3 to generate rotational motion, and finally the power output shaft 3 generates rotational motion and drives the auger rod 4 and the drill bit to rotate so as to cut the coal body, and the clamping mechanism 131 moves forward at the same time; when the drilling rig is turned on, the hydraulic pump station 17 is turned on, so that the support frame 1 moves to the right as a whole on the hydraulic lifting platform 1 under the drive of the hydraulic pressure, so that the auger rod 4 and the drill bit gradually enter the coal body during the rotation process, and the coal dust is gradually moved to the drilling hole mouth along the spiral blades arranged on the auger rod 4 during the rotation process of the auger rod 4 and the drill bit;

[0055] S3: After drilling to a certain depth, the drilling rig 13 is turned off and the hydraulic pump station 17 is turned on, so that the power input shaft 2 and the power output shaft 3, the auger rod 4 and the drill bit are moved toward the borehole opening as a whole, and then the hydraulic pump station 17 is adjusted to make the support frame 1 move to the left as a whole, and then the connection between the auger rod 4 and the power output shaft 3 is removed, and after adding a new drill rod, the drilling rig 13 is turned on again for drilling; S2 to S3 are repeated until the drilling reaches the designed depth, and then the drilling rig 13 can be turned off, and the auger rod 4 and the drill bit in the borehole are withdrawn immediately; after the gas extraction drilling construction is completed, it can be connected to the gas extraction pipeline under the coal mine to carry out gas extraction operations;

[0056] S4: Then, the adjusting handle is shaken to move the positioning slider 5 in the axial direction of the screw rod 6. After the positioning slider 5 moves to the position of the next designed drilling hole, the shaking of the adjusting handle 61 is stopped immediately. S1 to S3 are repeated until all the dense parallel drilling holes 15 along the direction of the coal seam of the mining working face are completed.

[0057] S5: If the coal seam is a thick or extra-thick coal seam 16, a circularly distributed borehole can be designed to implement coal seam gas extraction; in this process, all the circularly distributed gas extraction boreholes that need to be constructed on the mining face can be regarded as 5 layers of densely distributed parallel boreholes 15; during construction, it is implemented according to steps S1 to S4, the difference being that after each layer of densely distributed parallel boreholes 15 is constructed, the next layer of densely distributed parallel boreholes 15 is constructed again.

[0058] The present invention connects the auxiliary device to the drilling rig 13 through the universal joint 14, and multiple gas extraction boreholes can be constructed within the maximum stroke range of the slider allowed by the screw rod 6, which greatly reduces the frequency of movement of the drilling rig 13; and in view of the problem that thick and extra-thick coal seams 16 often have extraction blind spots, the construction of annularly distributed boreholes 161 for gas extraction is achieved by adjusting the hydraulic lifting platform, thereby eliminating the problem of the presence of interlayers in the thick and extra-thick coal seams 16 affecting the gas extraction effect.

[0059] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. A method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission, characterized in that: The following steps are involved: S1: At the location of the gas extraction drilling hole to be constructed, the construction device is assembled, the construction device comprising a power input shaft (2) located on the support frame (1), the power input shaft (2) is connected to the power output shaft (3) through a transmission structure, the power output shaft (3) is fixedly connected to the tail of the spiral drill rod (4), the head of the spiral drill rod (4) is fixedly connected with a drill bit, the position of the power output shaft (3) can be adjusted in the horizontal direction and the vertical direction to meet the requirements of dense drilling at different heights and positions, and then the clamping device of the drilling rig is connected to the power input shaft (2); the height and horizontal position of the spiral drill rod (4) are adjusted so that the position parameters of the drilling hole meet the design requirements; S2: The drilling machine is turned on, and the drilling machine transmits the rotational motion to the power input shaft (2), and the auger rod (4) drives the drill bit to work. At the same time, the hydraulic pump station (17) is turned on, and the power input shaft (2) and the power output shaft (3) can move toward the borehole under the drive of the hydraulic pump station (17). During the rotation process, the auger rod (4) and the drill bit gradually enter the coal body; S3: After the auger rod (4) is almost completely inserted into the borehole, the drilling machine (13) is turned off and the hydraulic pump station (17) is turned on, so that the power input shaft (2) and the power output shaft (3), the auger rod (4) and the drill bit are moved toward the borehole opening as a whole, and then the connection between the auger rod (4) and the power output shaft (3) is removed, and a new auger rod (4) is added, and the drilling machine (13) is turned on again to drill; steps S2 to S3 are repeated until the drilling reaches the designed depth, and then the drilling machine (13) can be turned off and the auger rod (4) and the drill bit are withdrawn; S4: After the gas extraction drilling is completed, it is immediately connected to the gas extraction pipeline in the coal mine to carry out gas extraction operations; S5: Then, the horizontal position of the power output shaft (3) is adjusted to move it to the position of the next designed drilling hole, and S1 to S4 are repeated until all the dense parallel drilling holes (15) along the direction of the coal seam of the mining working face are completed; A positioning slider (5) is arranged on the power output shaft (3), the power output shaft (3) is arranged at the lower part of the positioning slider (5), the power output shaft (3) passes through the positioning slider (5) and is connected to the positioning slider (5) through a bearing, a horizontal transmission hole (51) is opened on the upper part of the positioning slider (5), the axis of the transmission hole (51) is perpendicular to the axis of the power output shaft (3), a screw rod (6) passes through the transmission hole (51), the screw rod (6) and the transmission hole (51) are threadedly matched, and a parallel movement track of the positioning slider (5) is arranged below the screw rod (6); The two ends of the screw rod (6) are respectively fixed on the support frame (7) through the bearing fixing seat (71), and the support frame (7) is located on the hydraulic lifting platform (8). The support frame (7) can reciprocate in the drilling direction on the hydraulic lifting platform (8). In step S5, the height adjustment of the power output shaft (3) is achieved by adjusting the hydraulic lifting platform (8).

2. The method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission according to claim 1 is characterized in that: The step also includes: S6, when the coal seam is a thick or extra-thick coal seam (16), an annular distribution drill hole (161) is designed in an annular distribution form to implement coal seam gas extraction.

3. The method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission according to claim 2 is characterized in that: In step S6, all the gas extraction boreholes of the annularly distributed boreholes (161) to be constructed in the mining working face are regarded as 5 layers of dense parallel boreholes; during construction, the steps S1 to S5 are implemented, and after each layer of dense parallel boreholes is completed, the height of the power output shaft (3) is adjusted, and the next layer of dense parallel boreholes is constructed again.

4. The method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission according to claim 1 is characterized in that: The second support frame (7) is connected to the second hydraulic lifting platform (8) via a slide rail, and the second support frame (7) is connected to a hydraulic pump station (17). The hydraulic pump station (17) provides power for the second support frame (7), and the height adjustment of the power output shaft (3) is achieved by adjusting the second hydraulic lifting platform (8).

5. The method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission according to claim 1 is characterized in that: A pair of limiting rods (72) are symmetrically fixed to the side of the second bearing fixing seat (71) below the screw rod (6), the limiting rods (72) are located above the power output shaft (3), the positioning slide block (5) is located between the two limiting rods (72), and the space between the two limiting rods (72) is a parallel moving track.

6. The method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission according to claim 1 is characterized in that: An adjusting handle (61) is fixed to one end of the screw rod (6). In step S5, the adjusting handle (61) is shaken to move the positioning slider (5) in the axial direction of the screw rod (6). After the power output shaft (3) moves to the designed position of the next drilling hole, the shaking of the adjusting handle (61) is stopped.

7. The method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission according to claim 1 is characterized in that: The transmission structure comprises a left three-blade rotation transmission blade (9) fixed on the rear end of the power input shaft (2) and a right three-blade rotation transmission blade (11) fixed on the front end of the power output shaft (3); the left three-blade rotation transmission blade (9) and the right three-blade rotation transmission blade (11) are connected via a movable three-blade rotation transmission blade (10) in the middle; the three blades of the three-blade rotation transmission blade are symmetrically distributed, and a hinge unit is arranged at the top of each blade; hinge units are arranged on both sides of the blades on the movable three-blade rotation transmission blade (10) for connecting with the three-blade rotation transmission blade on the corresponding side; the corresponding hinge units between the left three-blade rotation transmission blade (9) and the movable three-blade rotation transmission blade (10), and between the right three-blade rotation transmission blade (11) and the movable three-blade rotation transmission blade (10) are respectively connected via a connecting rod (12) hinged thereto.

8. The method for dense drilling construction and coal seam gas extraction based on parallel shaft transmission according to claim 1 is characterized in that: In step S1, the support frame 1 (1) is connected to the hydraulic lifting platform 1 through a slide rail, and the support frame 1 (1) is connected to the hydraulic pump station (17). The hydraulic pump station (17) provides power for the support frame 1 (1), and the height adjustment of the power input shaft (2) is achieved by adjusting the hydraulic lifting platform 1.

Images