An impact loading test equipment with gas-solid coupling function

Abstract

An impact loading test device with gas-solid coupling function includes an impact test device, a drilling machine, and a coupling machine. The impact test device performs an impact test on the sample in the coupling machine through an incident rod and a transmission rod; the drilling machine is used to drill holes in the sample in the coupling machine; the coupling machine is used to apply confining pressure and gas coupling tests to the sample; the impact test device and the drilling machine are respectively located at two workstations, and the coupling machine moves to adapt to the two workstations to perform impact testing and drilling. The present invention can apply confining pressure to the sample around the periphery through hydraulic oil, and can apply pressurized gas to one end of the sample, and detect gas concentration or drill holes on the other end, so as to relatively realistically restore the actual stress environment of the coal rock, and strive to obtain relatively accurate parameters of the coal rock under this condition. In addition, after applying confining pressure, gas coupling, and drilling, the sample can be subjected to an impact test to further study the performance of the sample under this environment.

Description

Technical Field

[0001] The invention relates to coal-rock experimental technology, in particular to an impact loading test device with a gas-solid coupling function. Background Art

[0002] In the process of studying coal and rock, it is essential to investigate the impact of gas on coal and rock. This involves the reference of subsequent mining, support design, and coal mine gas control parameters. Therefore, it is also necessary to study the interaction mechanism between coal and rock and to reduce the performance parameters of coal and rock under the combined effects of confining pressure, mining, gas, etc.

[0003] Corresponding research equipment is currently available, such as the gas-solid coupling test device and method for drilling gas extraction in deep coal seams, disclosed in publication number CN105823854A. This device applies a constant pressure to the coal rock to simulate the ground pressure it experiences. Pressurized gas is then introduced to one side of the rock, and a hole is drilled from the other side. Parameters such as drill rod torque and axial pressure are measured during drilling. Ultimately, this device studies the gas migration patterns in deep coal rock under different stress conditions, coal seam gas extraction efficiency under different drilling parameters, gas drilling parameters under different stresses and gas pressures, coal and gas outburst mechanisms, and the relationship between drilling parameters and surrounding rock properties under different stresses. Applications of this device are also documented in "Study on the Tensile Properties and Damage and Fracture Mechanisms of Coal-Bearing Sandstones under High Strain Rates," a doctoral dissertation by Mao Rongrong, China University of Mining and Technology.

[0004] During the research on the device described in CN105823854A, the following problems were found in the device:

[0005] 1. The error of simulating confining pressure by uniaxial pressure is large because the confining pressure acts on the coal rock around the periphery rather than on one side or one axial direction.

[0006] 2. The test is conducted by applying high-pressure gas to one side of the coal rock and digging a hole on the other side. The area around the coal rock is difficult to seal, and the gas leakage is relatively large.

[0007] 3. Subsequent testing of coal rock after drilling is not possible, such as the stress-strain relationship of coal rock after confining pressure, gas coupling, and drilling. This is because the stress-strain relationship of coal rock constantly changes under these conditions during actual mining. By minimizing the actual environment of coal rock, we can obtain the most accurate parameters possible, providing a foundation for subsequent development and research. Summary of the Invention

[0008] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is to provide an impact loading test equipment with gas-solid coupling function, which can realize gas, confining pressure and coal-rock coupling tests.

[0009] To achieve the above objectives, the present invention provides an impact loading test device with a gas-solid coupling function, which is used to test a specimen and includes an impact test device, a drilling machine, and a coupling machine. The impact test device performs an impact test on the specimen in the coupling machine using an incident rod and a transmission rod; the drilling machine is used to drill a hole in the specimen in the coupling machine; and the coupling machine is used to apply confining pressure and gas coupling test to the specimen. The impact test device and the drilling machine are respectively located at two workstations, and the coupling machine moves to adapt to the two workstations to perform impact testing and drilling.

[0010] The coupling machine includes a coupling frame and two coupling mechanisms, the two coupling mechanisms are respectively mounted on the coupling frame, the coupling mechanism includes a coupling sleeve, an inner tube, an impact sleeve, and an impact head, the coupling sleeve can be axially slidably sleeved on the outer side of the inner tube and sealed with the inner tube; one end of the impact sleeve can be axially slidably mounted in the inner tube, and the other end of the impact sleeve is assembled with the impact head, and the impact head cannot be installed in the inner tube; second impact sleeve end faces are provided on both ends of the impact sleeve, and a hollow impact sleeve channel is provided inside the impact sleeve;

[0011] A sealing sleeve is mounted on the side wall of the sample, and end sleeves are mounted on both ends of the sample and the sealing sleeve, respectively, with end sleeve holes provided on the end sleeves; the end sleeves are inserted into the impact head and their end faces are pressed tightly against the end face of the second impact sleeve, thereby sealing the end of the impact sleeve;

[0012] One end of the inner tube away from the impact head is sealed by a sealing plate, and the inner tube on one side of the sample can be connected to high-pressure gas, and the inner tube on the other side of the sample can be connected to a gas sensor.

[0013] As a further improvement of the present invention, the impact head is provided with a pressure head groove, and the pressure head is installed in the pressure head groove; the pressure head is installed on the impact head through a spring sheet, and the spring sheet is used to keep the pressure head away from the axis of the impact head; the pressure head is respectively provided with a pressure head inclined surface and a pressure head side surface;

[0014] A tapered hole portion and a straight hole portion are respectively provided on the inner wall of the coupling sleeve, and both the tapered hole portion and the straight hole portion can be pressed tightly against the inclined surface of the pressure head; the straight hole portion is pressed tightly against the pressure head.

[0015] As a further improvement of the present invention, the coupling sleeve is assembled with the second slide, and the end of the inner tube away from the impact head can be axially slidably installed in the sealing tube and the sealing shell, the sealing shell is installed on the first slide, and the side of the sealing shell away from the sealing tube is assembled with the outer tube; a sealing groove is provided on the sealing shell, and a sealing plate is engaged and slidably installed in the sealing groove, one end of the sealing plate passes through the sealing shell and a handle groove is provided on this end; a sealing plate hole is also provided on the sealing plate, the sealing plate hole connects the sealing tube and the outer tube, and the inner tube can pass through the sealing plate hole;

[0016] When gas is connected, the end of the inner tube is located on the side of the sealing plate away from the outer tube; the sealing shell is installed with a sealing seat on the side of the sealing plate away from the outer tube, and a first sealing ring is installed on the sealing seat. The end face and inner wall of the first sealing ring are respectively pressed and sealed with the end face of the sealing plate located outside the inner tube and the outer wall of the inner tube;

[0017] The sealing tube is respectively provided with an air ring groove and a sealing ring groove, a second sealing ring is installed in the sealing ring groove, and the inner wall of the second sealing ring is pressed against the inner tube to seal the gap between the inner tube and the sealing tube; when gas is connected, an air hole is provided at the corresponding position of the inner tube and the air ring groove, the air hole connects the interior of the inner tube with the air ring groove, the air ring groove is connected with the air pipe, and the air pipe is connected with the pressurized gas storage device.

[0018] As a further improvement of the present invention, the first sealing ring is hollow inside, and the interior of the first sealing ring is connected to the first pressurized pipe, and the first pressurized pipe is connected to the gas storage device or the end of the inner tube near the impact sleeve. The first sealing ring is made of an elastic soft material. In the initial state, the first sealing ring does not contact or press against the inner tube.

[0019] The second sealing ring is made of elastic soft material and is hollow inside. The inside of the second sealing ring is connected to the second pressurized pipe. When the second pressurized pipe is connected to the gas storage device or the inner pipe near the impact sleeve in the initial state, the second sealing ring does not contact or press against the inner pipe.

[0020] As a further improvement of the present invention, a sealing convex ring is installed on the end of one of the coupling sleeves, and a coupling sealing ring is installed on the sealing convex ring; a sealing collar is installed on the end of the other coupling sleeve, and the sealing collar is sleeved outside the coupling sealing ring and squeezed and sealed with the coupling sealing ring.

[0021] As a further improvement of the present invention, a third sealing ring is installed on the inner wall of the coupling sleeve and the inner tube. The third sealing ring is made of an elastic soft elastic material, and when the confining pressure test is not performed, the third sealing ring is not pressed or in contact with the inner tube.

[0022] The interior of the third sealing ring is hollow and its inner wall can be pressed and sealed with the outer wall of the inner tube. The interior of the third sealing ring is connected to the sealing oil pipe, and the sealing oil pipe is connected to the hydraulic oil pipe that supplies hydraulic oil in the coupling sleeve or directly connected to high-pressure hydraulic oil.

[0023] As a further improvement of the present invention, two first slides and two second slides corresponding to the two coupling mechanisms are respectively axially slidably mounted on the guide shaft and are located on both sides of the sample, and the guide shaft is mounted on the coupling frame;

[0024] The two second slides are respectively assembled with the side cylinder shafts of the corresponding side cylinders, and the two side cylinders are respectively installed on the corresponding first slides;

[0025] The two first slide plates are respectively assembled with the double-outlet oil cylinder shafts at both ends of the double-outlet oil cylinder. The double-outlet oil cylinder is installed on the coupling bracket, and the coupling bracket is installed on the coupling frame.

[0026] As a further improvement of the present invention, a limiting groove is further provided on the sealing shell, and a limiting slider is further provided on the sealing plate. The limiting slider passes through the limiting groove and is assembled with one end of the splint; the splint has an elastic force to press the sealing shell.

[0027] As a further improvement of the present invention, the present invention further includes a locking member, the locking member is mounted on the corresponding first slide, the locking member is mounted with a locking rod, a sliding member, a first elastic sheet, a second elastic sheet, and a third elastic sheet, the locking rod is slidably mounted on the locking member, and an end of the locking rod inserted into the locking member is assembled with one end of the first elastic sheet and one end of the second elastic sheet, and an end of the locking rod extending out of the locking member is assembled with a lock button; the first elastic sheet, the second elastic sheet, and the third elastic sheet are all elastic;

[0028] The other end of the first elastic sheet and the other end of the second elastic sheet are respectively assembled with the inner wall of the locking member and the middle part of the slide; the first elastic sheet and the second elastic sheet have multiple pieces and are symmetrically installed on the locking rod with the center plane of the locking rod as the center; the third elastic sheet has two pieces and one end thereof is respectively assembled with the outer side of the assembly point of the slide and the second elastic sheet, and the other end of the third elastic sheet is assembled with the inner wall of the locking member; one end of the slide passes through the locking member and is pressed against the splint.

[0029] As a further improvement of the present invention, the drilling machine includes a drilling frame, a drilling slide, a drill rod, and a drilling screw. A drilling slide rail is installed on the drilling frame, and a drilling slide seat is provided on the drilling slide. The drilling slide seat is engaged and slidably installed on the drilling slide rail to provide a guide for the drilling slide.

[0030] The drilling screw is installed on the drilling machine frame and passes through the drilling slide. The drilling screw and the drilling slide are assembled by screwing. One end of the drilling screw is connected to the output shaft of the side shift motor.

[0031] The drilling slide is also respectively installed with a shaft seat, a first vertical plate, a second vertical plate, a drilling motor, a torque sensor, a drilling pressure sensor, and a drill rod. The drill rod passes through the shaft seat, the second vertical plate, and the torque sensor and is assembled with the push plate. The drill rod and the input shaft of the torque sensor cannot rotate relative to each other but can be assembled axially. The push plate is aligned with or pressed against the input shaft of the drilling pressure sensor, and the drilling pressure sensor is mounted on the first vertical plate.

[0032] A spiral blade and a sleeve are installed on one end of the drill rod close to the drill bit. The interior of the sleeve is a hollow sleeve cavity. The sleeve can be axially slidable and circumferentially rotated on the drill rod.

[0033] The drill rod is also equipped with a plurality of support bearings, which are assembled with the drill rod so as to be rotatable in a circular manner but not axially movable. A spring is installed between the support bearing closest to the sleeve and the sleeve, and the spring applies an elastic force to the sleeve to push the drill bit. The outer wall of the support bearing can be in close contact with the inner wall of the outer tube and the inner tube to support the drill rod.

[0034] The spiral blades are respectively fitted or pressed against the inner cavity of the sleeve and the impact sleeve channel; the spiral blades are made of flexible rubber material.

[0035] The beneficial effects of the present invention are:

[0036] This method applies confining pressure to the specimen using hydraulic oil, applies pressurized gas to one end of the specimen, and detects gas concentration or drill holes at the other end. This allows for a relatively realistic reconstruction of the actual stress environment of the coal rock, aiming to obtain relatively accurate parameters of the coal rock under these conditions, facilitating subsequent research and development. Furthermore, after applying confining pressure, gas coupling, and drilling, the specimen can be subjected to impact testing to further study its performance under these conditions, providing a foundation for subsequent research and mining. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a schematic diagram of the structure of the present invention Figure 1 ;

[0038] Figure 2 This is a schematic diagram of the structure of the present invention Figure 2 ;

[0039] Figure 3 This is a schematic diagram of the structure of the present invention Figure 3 (Cross-sectional view at the center plane where the axis of the drill rod 320 is located);

[0040] Figure 4 yes Figure 3 Enlarged view of point A in the middle;

[0041] Figure 5 yes Figure 4 Enlarged view of point B in the middle;

[0042] Figure 6 This is the structural diagram of the drilling machine Figure 1 ;

[0043] Figure 7 This is the structural diagram of the drilling machine Figure 2 ;

[0044] Figure 8 This is the structural diagram of the drilling machine Figure 3 ;

[0045] Figure 9 This is the structural diagram of the coupling machine Figure 1 ;

[0046] Figure 10 This is the structural diagram of the coupling machine Figure 2 ;

[0047] Figure 11 This is the structural diagram of the coupling machine Figure 3 ;

[0048] Figure 12 This is the structural diagram of the coupling machine Figure 4 (Cross-sectional view of the center plane where the axis of the outer tube 530 is located);

[0049] Figure 13 It is a cross-sectional view of the coupling machine located at the center plane where the axis of the impact sleeve 580 is located;

[0050] Figure 14 The structure diagram of two coupling mechanisms, sample 01, sealing sleeve 630, and end sleeve 640 Figure 1 ;

[0051] Figure 15 The structure diagram of two coupling mechanisms, sample 01, sealing sleeve 630, and end sleeve 640 Figure 2 ;

[0052] Figure 16 This is a schematic diagram of the structure of the impact head and impact sleeve;

[0053] Figure 17 It is a cross-sectional view of the locking member located at the center plane where the axis of the locking shaft 820 is located. DETAILED DESCRIPTION

[0054] The technical solutions in the embodiments of the present invention will be described clearly and completely below with reference to the accompanying drawings in the embodiments of the present invention.

[0055] In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inside", "outside", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are 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 direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention.

[0056] See also Figure 1-Figure 3The impact loading test equipment of this embodiment includes an impact test device, a drilling machine, and a coupling machine. The impact test device uses an incident rod 141 and a transmission rod 142 to perform an impact test on the sample 01 within the coupling machine. The drilling machine is used to drill holes in the sample within the coupling machine. The coupling machine is used to apply confining pressure to the sample 01 and perform a gas coupling test. The impact test device primarily clamps the sample using the incident rod 141 and the transmission rod 142. The incident rod 141 then applies an axial impact force to the sample. The shock wave generated during the impact process is detected to test the sample's impact resistance, strength, stress-strain relationship under impact load, and failure mechanism. The impact test device of this embodiment can utilize a Hopkinson pressure bar test system.

[0057] The impact test device and the drilling machine are respectively located at two workstations (impact station and drilling station), and the coupling machine moves to adapt to the two workstations to perform impact testing and drilling; when the coupling machine is not at these two workstations, confining pressure and / or gas coupling testing can be performed.

[0058] The coupling machine includes a frame 110 and a coupling frame 170. A coupling slide 173 is installed on the coupling frame 170. The coupling slide 173 is engaged with the coupling slide rail 111 and can be slidably assembled. The coupling screw 120 passes through the coupling frame 170 and is screwed therewith by a thread. The coupling screw 120 is installed on the frame 110 so that it can rotate circumferentially but cannot move axially. One end of the coupling screw 120 is assembled with a crank 130. When in use, the coupling screw 120 can be driven to rotate by the crank 130, thereby driving the coupling frame 170 to move along the axial direction of the coupling screw 120 to adapt to different workstations.

[0059] See also Figure 1-Figure 5 、 Figures 9-16 The coupling mechanism also includes two coupling mechanisms, comprising a coupling sleeve 710, an inner tube 610, an impact sleeve 580, and an impact head 590. The coupling sleeve 710 can be axially slidably mounted on the outer surface of the inner tube 610 and sealed therewith. One end of the impact sleeve 580 can be axially slidably mounted within the inner tube 610, and the other end of the impact sleeve 580 is assembled with the impact head 590, which cannot be installed within the inner tube 610. The impact sleeve 580 is respectively provided with a first impact sleeve end face 583 and a second impact sleeve end face 584 at each end. The impact sleeve 580 is provided with a hollow impact sleeve channel 582 inside, and an impact sleeve ring groove 581 is provided on the outer wall of the impact sleeve 580. The bolt 501 passes through the inner tube 610 and enters the impact sleeve ring groove 581, thereby limiting the axial displacement of the impact sleeve 580. This design is primarily intended to prevent the impact sleeve 580 from being pulled out of the inner tube 610, causing damage or loss to the impact sleeve 580.

[0060] The impact head 590 is provided with a pressure head groove 591, and a pressure head 720 is installed in the pressure head groove 591. The pressure head 720 is mounted on the impact head 590 via a spring plate 730. The spring plate 590 is used to keep the pressure head 720 away from the axis of the impact head 590. The pressure head 720 is provided with a pressure head inclined surface 721 and a pressure head side surface 722.

[0061] The inner wall of the coupling sleeve 710 is provided with a tapered hole portion 711 and a straight hole portion 712 , respectively. Both the tapered hole portion 711 and the straight hole portion 712 can fit tightly with the pressing head inclined surface 721 .

[0062] A sealing sleeve 630 is mounted on the sidewall of the specimen 01. End sleeves 640 are mounted on both ends of the specimen 01 and the sealing sleeve 630. Each end sleeve 640 is provided with an end sleeve hole 641. Both the sealing sleeve 630 and the end sleeve 640 are made of a flexible, elastic material. The end sleeve 640 is installed within the impact head 590, and its end face presses against the end face 584 of the second impact sleeve, thereby sealing the end of the impact sleeve 580. The straight hole 712 presses against the pressure head 720, causing the pressure head 720 to press the end sleeve 640 and the sealing sleeve 630 against the specimen 01. This design effectively secures the end sleeve 640 and the sealing sleeve 630, forming a seal against the sealing sleeve 630. This seal also forms a circumferential seal against the sidewall of the specimen 01. During the subsequent application of confining pressure, the confining pressure further presses the end sleeve 640 against the sealing sleeve 630, creating a more secure seal.

[0063] The coupling sleeve 710 of one coupling mechanism is mounted with a first pipe head 621 and a third pipe head 623, respectively. The coupling sleeve 710 of the other coupling mechanism is mounted with a second pipe head 622 and a fourth pipe head 624, respectively. The first pipe head 621, the third pipe head 623, the second pipe head 622, and the fourth pipe head 624 are connected to the inner side of the corresponding coupling sleeve 710. During use, the first pipe head 621 and the second pipe head 622 can be used to input and discharge hydraulic oil, respectively, while the third pipe head 623 and the fourth pipe head 624 can be used to exhaust air and connect to a hydraulic pressure gauge, respectively.

[0064] The end faces of the coupling sleeves 710 of the two coupling mechanisms are tightly sealed, and the coupling sleeves 710 are filled with pressurized hydraulic oil. The hydraulic oil applies confining pressure to the side of the sample 01 to simulate the confining pressure that the coal rock is subjected to in the actual environment.

[0065] In the initial state, the coupling sleeve 710 is positioned away from the impact head 590, and the pressure head 720 is positioned farthest from the axis of the impact head 590. During use, the sealing sleeve 630 is first installed on the specimen 01, and then the two end sleeves 640 are installed to form a specimen. One end of the specimen is inserted into one of the impact heads 590 and pressed against the corresponding second impact sleeve end face 584. The other or both impact heads 590 are then moved so that the other end of the specimen is installed into the other impact head 590 and pressed against the corresponding second impact sleeve end face 584, thereby completing the installation of the specimen. The two coupling sleeves 710 are moved so that the end faces of the two coupling sleeves 710 are pressed against each other and sealed. Pressurized hydraulic oil is then introduced into the coupling sleeves 710 until the oil pressure on the hydraulic oil gauge reaches a preset value. During this process, the air in the two coupling sleeves 710 is removed through the third pipe head 623 or the fourth pipe head 624, and the third pipe head 623 or the fourth pipe head 624 is closed through the gate valve to complete the application of confining pressure.

[0066] The coupling sleeve 710 is assembled with the second slide 192, and the end of the inner tube 610 away from the impact head 590 can be axially slidably installed in the sealing tube 570 and the sealing shell 540. The sealing shell 540 is installed on the first slide 191, and the side of the sealing shell 540 away from the sealing tube 570 is assembled with the outer tube 530; a sealing groove 541 is provided on the sealing shell 540, and a sealing plate 560 is engaged and slidably installed in the sealing groove 541, and one end of the sealing plate 560 passes through the sealing shell 540 and a handle groove 561 is provided on this end; a sealing plate hole 562 is also provided on the sealing plate 560, and the sealing plate hole 562 connects the sealing tube 570 and the outer tube 530, and the inner tube 610 can pass through the sealing plate hole 562.

[0067] When gas is connected, the end of the inner tube 610 is located on the side of the sealing plate 560 away from the outer tube 530, and is preferably in contact with the sealing plate 560; the sealing shell 540 is located on the side of the sealing plate 560 away from the outer tube 530 and is equipped with a sealing seat 550, and a first sealing ring 440 is installed on the sealing seat 550. The end face and inner wall of the first sealing ring 440 are respectively pressed and sealed with the end face of the sealing plate 560 located outside the inner tube 610 and the outer wall of the inner tube 610, thereby achieving sealing of the end of the inner tube 610 close to the sealing plate 560. Preferably, the interior of the first sealing ring 440 is hollow and communicates with a first pressurized tube 661. The first pressurized tube 661 communicates with a gas storage device or the end of the inner tube 610 near the impact sleeve 580. This allows pressurized gas to be introduced into the first sealing ring 440, causing the first sealing ring 440 to expand due to gas pressure and press against the end surface of the sealing plate 560 located outside the inner tube 610 and the outer wall of the inner tube 610, respectively, to achieve a better sealing effect. The first sealing ring 440 is made of a flexible and flexible material. In the initial state, the first sealing ring 440 does not contact or press against the inner tube 610, thereby avoiding affecting the movement of the inner tube 610.

[0068] The sealing tube 570 is respectively provided with an air ring groove 571 and a sealing ring groove 572, and a second sealing ring 450 is installed in the sealing ring groove 572. The inner wall of the second sealing ring 450 is pressed against the inner tube 610 to seal the gap between the inner tube 610 and the sealing tube 570; when gas is connected, the inner tube 610 and the air ring groove 571 are correspondingly provided with an air hole 611, and the air hole 611 connects the interior of the inner tube 610 with the air ring groove 571, and the air ring groove 571 is connected with the air pipe 660, and the air pipe 660 can be connected with the pressurized gas storage device, so that gas can be connected. Preferably, the second sealing ring 450 is made of a flexible, flexible material and is hollow. The interior of the second sealing ring 450 communicates with a second pressurized tube 662, which in turn communicates with a gas storage device or the end of the inner tube 610 proximate the impact sleeve 580. This allows pressurized gas to be introduced into the second sealing ring 450, causing the second sealing ring 450 to expand due to gas pressure and press against the outer wall of the inner tube 610, thereby achieving a better seal. In the initial state, the second sealing ring 450 does not contact or press against the inner tube 610, thereby avoiding affecting the movement of the inner tube 610.

[0069] When in use, adjust the inner tube 610 to Figure 13The specimen is clamped and confining pressure is applied to Specimen 01. High-pressure gas is then introduced to the air pipe 660 on one side, the first pressurized pipes 661 on both sides, and the second pressurized pipes 662 on both sides (the sealing plate 560 on this side is pulled out, so that the sealing half-hole 562 is not connected to the inner tube 610). This seals both sides of the inner tube 610 at the gas hole 611. The gas enters the corresponding inner tube 610 and contacts the end of Specimen 01 on that side, beginning to couple with Specimen 01. Gas pipe 660 on the other side is connected to a gas sensor to detect gas concentration and determine the concentration of gas passing through the sample. The sealing plate on this side does not need to be sealed. After the high-pressure gas is maintained for a certain period of time, the drill rod 320 of the drilling machine can pass through the outer and inner tubes on this side, contact the sample, and drill a hole in the sample. By continuously acquiring gas concentration data from the gas sensor, mining data under the high-pressure gas coupling of this coal rock can be obtained. This is the test method disclosed in Publication No. CN105823854A. During the drilling process, drill rod torque and axial pressure data can be obtained.

[0070] After the drilling is completed, the gas in the inner tube 610 can be extracted, the sealing plate can be opened, and the coupling machine can be moved to the position corresponding to the incident rod 141 and the transmission rod 142, and the incident rod 141 and the transmission rod 142 can be installed into the outer tube and the inner tube respectively (see Figure 4 ), until the end faces of the incident rod 141 and the transmission rod 142 are respectively pressed against the first impact end faces 583 of the impact sleeves 580 on both sides of the sample; after the corresponding strain gauges and auxiliary testing devices are installed on the incident rod 141 and the transmission rod 142, the impact test can be started. This test is obtained under the premise of confining pressure, and the data is closer to the actual stress environment of the coal rock, so the data is more reliable. Of course, the hydraulic oil in the coupling sleeve 710 can be extracted before testing, or the hydraulic oil in the coupling sleeve 710 can be extracted and filled with high-pressure gas before retesting to obtain data on the coal rock under different environments. During the impact process, since the impact sleeve can slide in the axial direction, the force acting on the impact sleeve will be transmitted to the sample, so the data obtained is also relatively accurate. Of course, under the premise of high precision requirements, the error correction function can be obtained after several tests, and this function can be used for error correction.

[0071] Preferably, see Figure 4 A sealing convex ring 713 is installed on the end of one coupling sleeve 710, and a coupling sealing ring 470 is installed on the sealing convex ring 713; a sealing ring 714 is installed on the end of the other coupling sleeve 710, and the sealing ring 714 is sleeved on the outside of the coupling sealing ring 470 and squeezed and sealed with the coupling sealing ring 470, thereby realizing the sealing of the two coupling sleeves 710.

[0072] Preferably, see Figure 3-Figure 4 、 Figure 13A third sealing ring 460 is installed on the inner wall of the coupling sleeve 710 and the inner tube 610. The third sealing ring 460 is made of an elastic soft elastic material, and when the confining pressure test is not performed, the third sealing ring 460 is not pressed or in contact with the inner tube 610.

[0073] The interior of the third sealing ring 460 is hollow and its inner wall can be pressed and sealed against the outer wall of the inner tube 610. The interior of the third sealing ring 460 is connected to the sealing oil pipe 670. The sealing oil pipe 670 is connected to the hydraulic oil pipe that supplies hydraulic oil in the coupling sleeve 710 or is directly connected to the high-pressure hydraulic oil, so that the high-pressure hydraulic oil can be connected to make the third sealing ring 460 pressed against the inner tube 610 to increase the sealing performance.

[0074] Preferably, see Figure 3-Figure 4 、 Figures 9-13 The two first slides 191 and the two second slides 192 corresponding to the two coupling mechanisms can be axially slidably mounted on the guide shaft 330 and are located on both sides of the sample 01. The guide shaft 330 is installed on the coupling frame 170.

[0075] The two second slides 192 are assembled with the side cylinder shafts 261 of their corresponding side cylinders 260. The two side cylinders 260 are mounted on their corresponding first slides 191. When activated, the side cylinders 260 drive the corresponding side cylinder shafts 261 to axially extend and retract, thereby driving the second slides 192 to slide along the guide shafts 330, and in turn, the corresponding coupling sleeves 710 to move. The two side cylinders 260 control the movement of the two coupling sleeves 710, thereby controlling whether they open or close together to seal. The coupling sleeves also drive the corresponding indenters to press against the specimen.

[0076] The two first slides 191 are respectively assembled with the dual-cylinder shafts 271 at each end of the dual-axis oil cylinder 270. The dual-axis oil cylinder 270 is mounted on the coupling bracket 172, and the coupling bracket 172 is mounted on the coupling bracket 170. During use, the dual-axis oil cylinder 270 can drive the dual-cylinder shafts 271 at its ends to move away from or toward each other synchronously, thereby driving the two first slides 191 to move away from or toward each other. The two first slides 191 then drive the two inner tubes 610 (impact sleeve, impact head) to move away from or toward each other, thereby controlling the two impact heads to clamp the specimen axially.

[0077] See also Figure 1-Figure 2 、 Figure 11 、 Figure 17The sealing shell 540 is also provided with a limiting groove 542, and the sealing plate 560 is also provided with a limiting slider 563. The limiting slider 563 passes through the limiting groove 542 and is assembled with one end of the clamping plate 910. The clamping plate 910 has an elastic force that presses against the sealing shell 540, thereby applying resistance to the movement of the sealing plate 560 through friction, thereby ensuring that the sealing plate 560 is in a stable state. When the sealing plate 560 needs to be moved, four fingers pass through the handle groove 561 and the thumb lifts the clamping plate 910 upward, so that the sealing plate 560 can be moved quickly. After moving into place, the clamping plate 910 is released so that the clamping plate 910 is restored to the state of being pressed against the sealing shell 540.

[0078] More preferably, to prevent misoperation of the sealing plate 560, this embodiment further includes a locking member 810, which is mounted on the corresponding first slide plate 191. The locking member 810 includes a locking rod 820, a sliding member 840, a first elastic piece 831, a second elastic piece 832, and a third elastic piece 833. The locking rod 820 is slidably mounted on the locking member 810, and one end of the locking rod 820 inserted into the locking member 810 is assembled with one end of the first elastic piece 831 and one end of the second elastic piece 832. The end of the locking rod 820 extending from the locking member 810 is assembled with a locking button 821, and the locking rod 820 can be driven axially by the locking button 821. The first elastic piece 831, the second elastic piece 832, and the third elastic piece 833 are all elastic.

[0079] The other ends of the first elastic piece 831 and the second elastic piece 832 are respectively attached to the inner wall of the locking member 810 and the middle portion of the sliding member 840. The first elastic piece 831 and the second elastic piece 832 are multiple pieces and are symmetrically mounted on the locking rod 820 with the center plane of the locking rod 820 as the center. The third elastic piece 833 is two pieces, one end of which is respectively attached to the outer side of the assembly point of the sliding member 840 and the second elastic piece 832, and the other end of the third elastic piece 833 is attached to the inner wall of the locking member 810. One end of the sliding member 840 passes through the locking member 810 and is pressed against the clamping plate 910, thereby preventing the clamping plate 910 from being lifted.

[0080] Figure 17 The locked state is shown. Due to the stable triangular structure formed between the second elastic piece 832 and the slider 840, the slider 840 cannot slide, and the clamping plate 910 cannot be lifted upward. Pushing the lock rod 820 toward the slider 840 causes the first elastic piece 831 and the second elastic piece 832 to change to the 831-1 and 832-1 positions, respectively. The restriction imposed by the second elastic piece 832 on the slider 840 is now lifted, allowing the slider 840 to slide and the clamping plate 910 to be lifted, thus unlocking the device. This design is primarily intended to prevent accidental operation; forcing the sealing plate to operate requires the lock rod 820 to be operated.

[0081] See also Figure 9 To detect the axial clamping force of the two impact heads 590 on the specimen 01 and the clamping force between the two coupling sleeves 710, this embodiment also installs a second pressure sensor 282 and a first pressure sensor 281 on the coupling bracket 172, corresponding to the two first slides 191 and the two second slides 192, respectively. During operation, the two second slides 192 compress the corresponding second pressure sensors 282, thereby detecting the axial clamping force of the two impact heads 590 on the specimen 01; while the two first slides 191 compress the corresponding first pressure sensors 281, thereby detecting the clamping force between the two coupling sleeves 710. After clamping, since the impact sleeves can slide axially, subsequent impact testing is not affected.

[0082] See also Figure 3 A waste bin 180 is also mounted on the coupling frame 170. The interior of the waste bin 180 defines a hollow waste chamber 181. The waste chamber 181 is open at the top and faces the two coupling mechanisms. During use, samples, sample fragments, hydraulic oil, and the like within the two coupling mechanisms can fall into the waste chamber 181 for storage.

[0083] See also Figure 3 A drainage tube 531 is also installed on the outer tube 530, and the drainage tube 531 connects the interior of the outer tube 531 with the waste chamber 181, so that the debris in the outer tube can be input into the waste chamber 181 through the drainage tube 531.

[0084] See also Figures 1-8 The drilling machine includes a drilling frame 150, a drilling slide 160, a drill rod 320, and a drilling screw 310. A drilling slide rail 151 is installed on the drilling frame 150, and a drilling slide seat 161 is provided on the drilling slide 160. The drilling slide seat 161 is engaged and slidably installed on the drilling slide rail 151 to provide guidance for the drilling slide 160.

[0085] The drilling screw 310 is installed on the drilling machine frame 150 and passes through the drilling slide 160. The drilling screw 310 and the drilling slide 160 are assembled by threaded engagement. One end of the drilling screw 310 is connected to the output shaft of the side shift motor 210. After the side shift motor 210 is started, it can drive the drilling screw 310 to rotate in a circle, thereby driving the drilling slide 160 to slide along the drilling slide rail 151.

[0086] The drilling slide 160 is also respectively equipped with a shaft seat 162, a first vertical plate 163, a second vertical plate 164, a drilling motor 240, a torque sensor 252, a drilling pressure sensor 251, and a drill rod 320. The drill rod 320 passes through the shaft seat 162, the second vertical plate 164, and the torque sensor 252 and is assembled with the push plate 322. The drill rod 320 and the input shaft (hollow) of the torque sensor 252 cannot rotate relative to each other in a circular manner and can be assembled axially, so that the torque sensor 252 can detect the torque of the drill rod 320; the push plate 322 is opposite to or pressed against the input shaft of the drilling pressure sensor 251, and the drilling pressure sensor 251 is installed on the first vertical plate 163, so that the axial pressure of the drill rod 320 can be detected.

[0087] The drill rod 320 is also equipped with a worm gear 442, which is engaged with the worm 441 for transmission. The worm 441 is arranged on the drilling motor shaft 241, and one end of the drilling motor shaft 241 is installed in the drilling motor 240. The drilling motor 240 is installed on the drilling slide 160. After the drilling motor 240 is started, it can drive the drill rod 320 to rotate. The end of the rotating rod 320 is equipped with a drill bit 321, and the drill bit 321 is used to drill the sample 01.

[0088] The drilling frame 150 is also equipped with an electric drum payout 230 and a pull-wire displacement sensor 220. The electric drum payout 230 is used to retract and release a cable 231. The cable 231 is fixedly mounted to the drilling carriage 160 to maintain power supply and communication with the drilling motor 240, drilling pressure sensor 251, and torque sensor 252. The pull-wire displacement sensor 220 has a pull-wire 221 fixedly mounted to the drilling carriage 160 to detect displacement between the drilling carriage 160 and the pull-wire displacement sensor 220.

[0089] A spiral blade 520 and a sleeve 430 are installed on one end of the drill rod 320 close to the drill bit 322. The interior of the sleeve 430 is a hollow sleeve inner cavity 431. The sleeve 430 can be axially slid and circumferentially rotated on the drill rod 320, and a limit ring 323 is provided on the part of the drill rod 320 located inside the sleeve 430. The limit ring 323 is used to limit the maximum displacement point of the sleeve 430 moving toward the drill bit.

[0090] The drill rod 320 is also equipped with multiple support bearings 410. The support bearings 410 and the drill rod 320 are assembled so as to rotate circumferentially but not move axially. An end bearing 420 is mounted on the support bearing 410 closest to the sleeve 430, and another end bearing 420 is mounted on the end of the sleeve 430 away from the drill bit. A spring 510 is mounted on the portion of the drill rod 320 between the two end bearings 420. The spring 510 applies a spring force to the sleeve 430, pushing it toward the drill bit. The outer wall of the support bearing 410 can be in close contact with the inner walls of the outer tube 530 and the inner tube 610 to support the drill rod.

[0091] In the initial state, the closed end of the sleeve is pressed against the limiting ring 323, and the sleeve is at the end closest to the drill bit 321. During use, the end of the drill rod 320 provided with the drill bit 321 passes through the outer tube 530 and the inner tube 610 in sequence until the drill bit 321 is pressed against the end face of the sample 01, and before that, the end face of the sleeve 430 is pressed against the end face 583 of the first impact sleeve, thereby squeezing the spring to allow the drill rod to continue to move toward the sample. This design is mainly to press the sleeve against the end face 583 of the first impact sleeve, so that the fine residue from subsequent hole digging can enter the sleeve, reducing contamination of the inner and outer tubes, so as to avoid affecting the subsequent installation and use of the incident rod and the transmission rod. When drilling, the drill rod is fed axially toward the sample, but the sleeve does not move, and the fine residue is input into the sleeve through the spiral blade for storage.

[0092] The spiral blades 520 fit or press against the sleeve cavity 431 and the impact sleeve channel 582, respectively, to ensure effective conveyance of fine slag. The spiral blades 520 can be made of a flexible rubber material. During use, the fine slag is deposited into the sleeve cavity 431. After drilling is complete, the spiral blades 520 seal the sleeve cavity 431, effectively preventing the escape of the fine slag. After the sleeve is removed, the spiral blades can be reversed to squeeze the sleeve and discharge the fine slag.

[0093] The usage of this embodiment is roughly as follows:

[0094] S1. The coupling machine is located at the incident rod 141 and the transmission rod 141. The sealing sleeve 630 and the end sleeve 640 are respectively mounted on the sample 01 to obtain the sample.

[0095] S2. Place one end of the specimen into the impact head 590 on one side, activate the side cylinder 260 on the other side, so that the impact head 590 on the other side is fitted over the other end of the specimen, and activate both side cylinders 260 until the pressure values of the second pressure sensors 282 corresponding to the two side cylinders 260 reach the preset requirements;

[0096] S3. Start the dual-shaft oil cylinder 270 to drive the two coupling sleeves 710 to move closer to each other until the pressure values of the two first pressure sensors 281 reach the preset requirements. At this time, the two coupling sleeves 710 are pressed and sealed against each other, and the coupling sleeves 710 drive the corresponding pressure heads 720 to press the end sleeves 640.

[0097] S4. Pressurized hydraulic oil is introduced into the two coupling sleeves 710 until a preset pressure value is reached, and then maintained for a period of time to simulate confining pressure;

[0098] S5. Close the sealing plates on both sides and introduce pressurized gas into the inner tube 610 on one side. Use the gas sensor on the other side to detect the gas concentration. Maintain this pressure for a period of time. This allows the gas to pass axially through the sample and reach the other side, where it is detected by the gas sensor on that side. Of course, this gas sensor can be omitted as long as sufficient time is sufficient.

[0099] S6. Open the sealing plate 560, move the coupling frame to the drilling machine, start the side shift motor 210, and drive the drill rod 320 into the outer tube 530 and the inner tube 610 until the drill bit 321 is pressed against the end of the sample 01. At this time, the drilling pressure sensor 251 outputs a preset pressure value.

[0100] S7, starting the drilling motor 240, driving the drill rod to rotate, drilling the sample, and monitoring the value of the gas sensor, the torque of the drill rod, and the axial pressure of the drill rod during this process;

[0101] S8. After the drilling is completed, the drill rod is removed from the coupling frame, and the coupling frame is moved to the incident rod 141. The incident rod and the transmission rod are respectively installed into the inner tubes 610 at both ends until the incident rod 141 and the transmission rod 142 respectively reach the preset clamping force, and then preparation for the impact test is started. After the preparation is completed, the impact test is carried out.

[0102] S9. After the impact test is completed, the hydraulic oil is extracted, the two coupling sleeves 710 and the two impact heads 590 are separated and restored to their initial state, and then the debris on the coupling sleeves 710 and the impact head 590 is cleaned.

[0103] Anything not described in detail in the present invention is well known to those skilled in the art.

[0104] The above describes in detail the preferred embodiments of the present invention. It should be understood that those skilled in the art can make numerous modifications and variations based on the concepts of the present invention without inventive effort. Therefore, any technical solutions that can be derived by those skilled in the art through logical analysis, reasoning, or limited experimentation based on the concepts of the present invention and the prior art should be within the scope of protection defined by the claims.

Claims

1. An impact loading test device with gas-solid coupling function, which is used to test a specimen, and is characterized by: The device comprises an impact test device, a drilling machine, and a coupling machine. The impact test device performs an impact test on a sample in the coupling machine through an incident rod and a transmission rod. The drilling machine is used to drill holes in the sample in the coupling machine. The coupling machine is used to apply confining pressure and gas coupling tests to the sample. The impact test device and the drilling machine are respectively located at two workstations, and the coupling machine moves to adapt to the two workstations to perform impact testing and drilling. The coupling machine includes a coupling frame and two coupling mechanisms, the two coupling mechanisms are respectively mounted on the coupling frame, the coupling mechanism includes a coupling sleeve, an inner tube, an impact sleeve, and an impact head, the coupling sleeve can be axially slidably sleeved on the outer side of the inner tube and sealed with the inner tube; one end of the impact sleeve can be axially slidably mounted in the inner tube, and the other end of the impact sleeve is assembled with the impact head, and the impact head cannot be installed in the inner tube; second impact sleeve end faces are provided on both ends of the impact sleeve, and a hollow impact sleeve channel is provided inside the impact sleeve; A sealing sleeve is mounted on the side wall of the sample, and end sleeves are mounted on both ends of the sample and the sealing sleeve, respectively, with end sleeve holes provided on the end sleeves; the end sleeves are inserted into the impact head and their end faces are pressed tightly against the end face of the second impact sleeve, thereby sealing the end of the impact sleeve; One end of the inner tube away from the impact head is sealed by a sealing plate, and the inner tube on one side of the sample can be connected to high-pressure gas, and the inner tube on the other side of the sample can be connected to a gas sensor.

2. The impact loading test equipment according to claim 1, characterized in that: The impact head is provided with a pressure head groove, and the pressure head is installed in the pressure head groove; the pressure head is installed on the impact head through a spring sheet, and the spring sheet is used to keep the pressure head away from the axis of the impact head; the pressure head is respectively provided with a pressure head inclined surface and a pressure head side surface; A tapered hole portion and a straight hole portion are respectively provided on the inner wall of the coupling sleeve, and both the tapered hole portion and the straight hole portion can be pressed tightly against the inclined surface of the pressure head; the straight hole portion is pressed tightly against the pressure head.

3. The impact loading test equipment according to claim 1, characterized in that: The coupling sleeve is assembled with the second slide, and the end of the inner tube away from the impact head can be axially slidably installed in the sealing tube and the sealing shell. The sealing shell is installed on the first slide, and the side of the sealing shell away from the sealing tube is assembled with the outer tube; a sealing groove is provided on the sealing shell, and a sealing plate is engaged and slidably installed in the sealing groove, and one end of the sealing plate passes through the sealing shell and is provided with a handle groove; a sealing plate hole is also provided on the sealing plate, which connects the sealing tube and the outer tube, and the inner tube can pass through the sealing plate hole; When gas is connected, the end of the inner tube is located on the side of the sealing plate away from the outer tube; the sealing shell is installed with a sealing seat on the side of the sealing plate away from the outer tube, and a first sealing ring is installed on the sealing seat. The end face and inner wall of the first sealing ring are respectively pressed and sealed with the end face of the sealing plate located outside the inner tube and the outer wall of the inner tube; The sealing tube is respectively provided with an air ring groove and a sealing ring groove, a second sealing ring is installed in the sealing ring groove, and the inner wall of the second sealing ring is pressed against the inner tube to seal the gap between the inner tube and the sealing tube; when gas is connected, an air hole is provided at the corresponding position of the inner tube and the air ring groove, the air hole connects the interior of the inner tube with the air ring groove, the air ring groove is connected with the air pipe, and the air pipe is connected with the pressurized gas storage device.

4. The impact loading test equipment according to claim 3, characterized in that: The first sealing ring is hollow and communicates with a first pressurized pipe. The first pressurized pipe communicates with a gas storage device or an end of the inner tube near the impact sleeve. The first sealing ring is made of an elastic soft material. In an initial state, the first sealing ring does not contact or press against the inner tube. The second sealing ring is made of elastic soft material and is hollow inside. The inside of the second sealing ring is connected to the second pressurized pipe. When the second pressurized pipe is connected to the gas storage device or the inner pipe near the impact sleeve in the initial state, the second sealing ring does not contact or press against the inner pipe.

5. The impact loading test equipment according to claim 1, wherein: A sealing convex ring is installed on the end of the coupling sleeve, and a coupling sealing ring is installed on the sealing convex ring; a sealing collar is installed on the end of the other coupling sleeve, and the sealing collar is sleeved outside the coupling sealing ring and squeezed and sealed with the coupling sealing ring.

6. The impact loading test equipment according to claim 1, characterized in that: A third sealing ring is installed on the inner wall of the coupling sleeve and the inner tube. The third sealing ring is made of an elastic soft elastic material, and when the confining pressure test is not performed, the third sealing ring is not pressed or in contact with the inner tube. The interior of the third sealing ring is hollow and its inner wall can be pressed and sealed with the outer wall of the inner tube. The interior of the third sealing ring is connected to the sealing oil pipe, and the sealing oil pipe is connected to the hydraulic oil pipe that supplies hydraulic oil in the coupling sleeve or directly connected to high-pressure hydraulic oil.

7. The impact loading test equipment according to claim 1, characterized in that: Two first slides and two second slides corresponding to the two coupling mechanisms are respectively axially slidably mounted on the guide shaft and are located on both sides of the sample. The guide shaft is mounted on the coupling frame. The two second slides are respectively assembled with the side cylinder shafts of the corresponding side cylinders, and the two side cylinders are respectively installed on the corresponding first slides; The two first slide plates are respectively assembled with the double-outlet oil cylinder shafts at both ends of the double-outlet oil cylinder. The double-outlet oil cylinder is installed on the coupling bracket, and the coupling bracket is installed on the coupling frame.

8. The impact loading test equipment according to claim 3, characterized in that: The sealing shell is also provided with a limiting sliding groove, and the sealing plate is also provided with a limiting slider. The limiting slider passes through the limiting sliding groove and is assembled with one end of the clamping plate; the clamping plate has an elastic force to press against the sealing shell.

9. The impact loading test equipment according to claim 8, characterized in that: The locking member is mounted on the corresponding first slide plate, and a locking rod, a sliding member, a first elastic sheet, a second elastic sheet, and a third elastic sheet are mounted on the locking member. The locking rod is slidably mounted on the locking member, and one end of the locking rod inserted into the locking member is assembled with one end of the first elastic sheet and one end of the second elastic sheet, and one end of the locking rod passing through the locking member is assembled with the lock button; the first elastic sheet, the second elastic sheet, and the third elastic sheet are all elastic. The other end of the first elastic sheet and the other end of the second elastic sheet are respectively assembled with the inner wall of the locking member and the middle part of the slide; the first elastic sheet and the second elastic sheet have multiple pieces and are symmetrically installed on the locking rod with the center plane of the locking rod as the center; the third elastic sheet has two pieces and one end thereof is respectively assembled with the outer side of the assembly point of the slide and the second elastic sheet, and the other end of the third elastic sheet is assembled with the inner wall of the locking member; one end of the slide passes through the locking member and is pressed against the splint.

10. The impact loading test equipment according to claim 1, wherein: The drilling machine includes a drilling frame, a drilling slide, a drill rod, and a drilling screw. A drilling slide rail is installed on the drilling frame, and a drilling slide seat is provided on the drilling slide. The drilling slide seat is engaged and slidably installed on the drilling slide rail to provide a guide for the drilling slide. The drilling screw is installed on the drilling machine frame and passes through the drilling slide. The drilling screw and the drilling slide are assembled by screwing. One end of the drilling screw is connected to the output shaft of the side shift motor. The drilling slide is also respectively installed with a shaft seat, a first vertical plate, a second vertical plate, a drilling motor, a torque sensor, a drilling pressure sensor, and a drill rod. The drill rod passes through the shaft seat, the second vertical plate, and the torque sensor and is assembled with the push plate. The drill rod and the input shaft of the torque sensor cannot rotate relative to each other but can be assembled axially. The push plate is aligned with or pressed against the input shaft of the drilling pressure sensor, and the drilling pressure sensor is mounted on the first vertical plate. A spiral blade and a sleeve are installed on one end of the drill rod close to the drill bit. The interior of the sleeve is a hollow sleeve cavity. The sleeve can be axially slidable and circumferentially rotated on the drill rod. The drill rod is also equipped with a plurality of support bearings, which are assembled with the drill rod so as to be rotatable in a circular manner but not axially movable. A spring is installed between the support bearing closest to the sleeve and the sleeve, and the spring applies an elastic force to the sleeve to push the drill bit. The outer wall of the support bearing can be in close contact with the inner wall of the outer tube and the inner tube to support the drill rod. The spiral blades are respectively fitted or pressed against the inner cavity of the sleeve and the impact sleeve channel; the spiral blades are made of flexible rubber material.

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