A safety energy absorption device and method for hydraulic fracturing of coal mine roof

Abstract

The present application discloses a safety energy-absorbing device and method for hydraulic fracturing of coal mine roof, belonging to the technical field of coal mine mining, and solves the problem that in the process of hydraulic fracturing in the prior art, the drill pipe is ejected, which poses a hazard to the personal safety of construction personnel. The device includes: a liquid supply pipeline, a part of the liquid supply pipeline is located in the borehole of the roof, and the liquid supply pipeline has holes for providing a passage for the fracturing fluid to flow; a hole sealer, connected to the liquid supply pipeline and located on one side away from the drill opening of the borehole, for sealing the non-target fracturing area in the roof; an anti-slip mechanism, at least connected to the liquid supply pipeline located in the borehole and in contact with the inner wall of the borehole to provide a supporting force for the liquid supply pipeline; an energy-absorbing mechanism, connected to the side of the liquid supply pipeline away from the anti-slip mechanism and in contact with the inner wall of the roof, for providing a buffering force opposite to the movement direction of the liquid supply pipeline when the liquid supply pipeline is ejected. The present application improves the safety during the operation of hydraulic fracturing of the roof.

Description

Technical Field

[0001] This application belongs to the technical field of coal mining, and more particularly relates to a safety energy-absorbing device and method for hydraulic fracturing of coal mine roofs. Background Art

[0002] With the continuous increase in the depth and intensity of coal mining, the problem of coal and rock dynamic disasters has become more serious. Therefore, it is necessary to take effective technical measures for pressure relief to reduce the outburst risk of coal seams and reduce the occurrence of outburst accidents. As an effective pressure relief method, hydraulic fracturing has been well applied in preventing and controlling coal mine dynamic disasters. For example, in coal mining, the hydraulic fracturing technology is used to solve the stability problem of roof strata, weaken the hard and intact roof of the coal mining face, reduce the roof rigidity and stress concentration, and reduce the risk of rock burst.

[0003] However, during the process of hydraulic fracturing, high-pressure liquid is injected into the borehole through the drill pipe. If the hole sealing quality is poor or the pressure is too high, the liquid may flow back along the gap between the drill pipe and the hole wall, generating an outward reaction force, causing the drill pipe to be ejected and endangering the personal safety of construction workers. Moreover, it will not only cause waste of fracturing fluid, but also require repeated high-pressure fracturing, which is not energy-saving and environmentally friendly.

[0004] In this context, how to provide a technical solution to improve the safety during the operation of roof hydraulic fracturing has become an urgent technical problem to be solved. Summary of the Invention

[0005] In view of the above analysis, the embodiments of the present invention aim to provide a safety energy-absorbing device and method for hydraulic fracturing of coal mine roofs to solve the problem that the drill pipe is ejected during the process of hydraulic fracturing in the prior art, which endangers the personal safety of construction workers.

[0006] The present invention provides a safety energy-absorbing device for hydraulic fracturing of coal mine roofs, comprising:

[0007] A liquid supply pipeline, a part of which is located in the borehole on the roof. The liquid supply pipeline has holes for providing a passage for the fracturing fluid to flow.

[0008] A hole sealer, connected to the liquid supply pipeline and located on one side away from the drill opening of the borehole, for closing the non-target fracturing area in the roof.

[0009] An anti-slip mechanism, at least connected to the liquid supply pipeline located in the borehole. The anti-slip mechanism has a first state. When the anti-slip mechanism is in the first state, the anti-slip mechanism abuts against the inner wall of the borehole to provide a supporting force for the liquid supply pipeline.

[0010] An energy absorbing mechanism is connected to a side of the liquid supply pipe away from the anti-slip mechanism, and the energy absorbing mechanism conflicts with the inner wall of the top plate. The energy absorbing mechanism is used to provide a buffering force opposite to the movement direction of the liquid supply pipe when the liquid supply pipe rushes out of the drill hole.

[0011] Optionally, the anti-slip mechanism includes:

[0012] a fixing assembly, wherein a first end of the fixing assembly is connected to a liquid supply pipeline located in the borehole and near the drill opening, and a second end of the fixing assembly is connected to the liquid supply pipeline located outside the borehole and is in continuous communication with the liquid supply pipeline;

[0013] A sliding component is sleeved on the fixed component and can move along the fixed component;

[0014] A support assembly is sleeved on the fixed assembly and located above the sliding assembly, and the support assembly is also connected to the sliding assembly;

[0015] Among them, when the sliding component and the fixed component have a first relative posture, the support component is in the first state, and the support component conflicts with the inner wall of the drill hole; when the sliding component and the fixed component have a second relative posture, the support component is in the second state.

[0016] Optionally, the coal mine roof hydraulic fracturing safety energy absorption device meets at least one or more of the following requirements:

[0017] The fixing assembly includes: a sleeve rod, a control button is provided on the sleeve rod, and a first elastic member located in the sleeve rod and linked with the control button;

[0018] The sliding assembly includes a sleeve having an opening, the opening being adapted to fit the control button, and when the control button is fixed in the opening, the sliding assembly and the fixing assembly have the first relative posture.

[0019] Optionally, the sliding assembly has a first mounting hole on a side close to the supporting assembly, and the sliding assembly is connected to the supporting assembly through the first mounting hole.

[0020] Optionally, the support assembly includes:

[0021] A collar, sleeved on the fixing assembly;

[0022] a support plate rotatably connected to the collar, wherein the support assembly is in the first state, and a bottom of the support plate is opposite to an outer wall of the fixing assembly;

[0023] A support member is disposed on the support plate. When the support assembly is in the first state, the support member abuts against the inner wall of the borehole.

[0024] A connecting member is used to connect the support plate and the sliding assembly.

[0025] Optionally, the hydraulic fracturing safety energy absorption device for coal mine roof satisfies one or more of the following:

[0026] The number of the support plates is multiple, and the multiple support plates are symmetrically arranged along the collar, and the numbers on both sides are the same.

[0027] The number of the support members is multiple, and the multiple support members can be disposed on one support plate. Among them, the number of the support members is determined based on the total mass of the liquid supply pipeline, the depth of the borehole in the roof, and the inclination angle of the borehole.

[0028] One side of the support member away from the support plate has an arc-shaped contact surface, and the arc-shaped contact surface is adapted to the outer diameter of the fixing component.

[0029] The included angle between the support members is 90 degrees.

[0030] A hinge is disposed on the outer wall of the collar, and the support plate is rotatably connected to the collar through the hinge.

[0031] One side of the support plate away from the support member has a second mounting hole, and the connecting member connects the support plate and the sliding assembly through the second mounting hole.

[0032] The connecting member includes a connecting rod or a connecting chain.

[0033] Optionally, the hydraulic fracturing safety energy absorption device for coal mine roof satisfies at least one or more of the following:

[0034] One side of the support member away from the support plate has an anti-slip member. When the support assembly is in the first state, the anti-slip member abuts against the inner wall of the borehole.

[0035] A first limiting member is disposed on the fixing component and is located above the collar.

[0036] A second limiting member is disposed on the fixing component and is located between the collar and the sliding assembly.

[0037] A first buffer member is wound around the fixing component and is located between the collar and the second limiting member.

[0038] The position of the second limiting member on the fixing assembly is determined by the position of the collar on the fixing assembly and the length of the first buffer member.

[0039] Optionally, the energy absorbing mechanism includes:

[0040] An anti-collision component, wherein one side of the anti-collision component has a third mounting hole, the side of the anti-collision component facing away from the third mounting hole has a third mounting hole, the side of the anti-collision component facing away from the third mounting hole has a through-channel connected to the liquid supply pipe and staggered with the third mounting hole, and an opening communicating with the through-channel and located inside the anti-collision component, the opening of the opening being located at the bottom of the anti-collision component;

[0041] A buffer assembly is arranged between the anti-impact assembly and the inner wall of the top plate, the first end of the buffer assembly is connected to the mounting hole, and the second end of the buffer assembly is used to interfere with the inner wall of the top plate, and is used to provide the buffering force when the liquid supply pipe is rushed out of the drilled hole, wherein the number of the buffer assemblies is determined based on the total mass of the liquid supply pipe, the depth of the drilled hole in the top plate, and the inclination angle of the drilled hole.

[0042] Optionally, the buffer assembly includes:

[0043] a connecting portion connected to the third mounting hole;

[0044] a main body portion having a hollow passage and connected to the connecting portion;

[0045] a second elastic member suspended in the hollow channel;

[0046] a third limiting member disposed on the main body and located below the second elastic member;

[0047] a telescopic rod, wherein a first end of the telescopic rod is located above the third limiting member in the hollow channel and is capable of compressing the second elastic member;

[0048] A third elastic member is wound around the telescopic rod.

[0049] Accordingly, the present invention further provides a coal mine roof hydraulic fracturing method, which is applied to the coal mine roof hydraulic fracturing safety energy absorption device described in any of the above examples, and the method comprises:

[0050] Drill holes in the roof;

[0051] A fluid supply pipeline is provided at least in the borehole, wherein the fluid supply pipeline has holes for providing a passage for the fracturing fluid to flow;

[0052] A plugging device is provided on one side of the drill hole away from the drill opening of the borehole. The plugging device is connected to the liquid supply pipeline and is used to seal the non-target fracturing area in the roof.

[0053] A non-slip mechanism is provided. The non-slip mechanism is at least connected to the liquid supply pipeline located in the borehole, and the non-slip mechanism is in a first state to abut against the inner wall of the borehole to provide a supporting force for the liquid supply pipeline.

[0054] An energy absorption mechanism is provided and is connected to the side of the liquid supply pipeline away from the non-slip mechanism, and the energy absorption mechanism abuts against the inner wall of the roof. The energy absorption mechanism is used to provide a buffering force in the opposite direction to the movement direction of the liquid supply pipeline when the liquid supply pipeline rushes out of the borehole.

[0055] The fracturing fluid is provided to the liquid supply pipeline through the non-slip mechanism and the energy absorption mechanism.

[0056] Compared with the existing solutions, in the coal mine roof hydraulic fracturing safety energy absorption device provided by the present invention, on the one hand, during the process of providing fracturing fluid into the borehole through the liquid supply pipeline, the non-slip mechanism is at least connected to the liquid supply pipeline located in the borehole, and the non-slip mechanism abuts against the inner wall of the borehole, which can provide a supporting force for the liquid supply pipeline, improve the stability of the liquid supply pipeline. Even if there are problems such as poor plugging quality or excessive pressure, the liquid supply pipeline can still work stably, reducing the probability of the liquid supply pipeline recoiling. On the other hand, by providing an energy absorption mechanism between the liquid supply pipeline and the inner wall of the roof, a buffering force in the opposite direction to the movement direction of the liquid supply pipeline can be provided when the liquid supply pipeline recoils, reducing the impact caused by the recoil of the liquid supply pipeline and enhancing the safety during the coal mine roof hydraulic fracturing operation. Description of the Drawings

[0057] In order to more clearly illustrate the technical solutions in the embodiments of this specification or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments recorded in the embodiments of this specification. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0058] Figure 1 It is a schematic diagram of the application scenario of a coal mine roof hydraulic fracturing safety energy absorption device in an embodiment of the present invention;

[0059] Figure 2 It is a schematic structural diagram of a non-slip mechanism in an embodiment of the present invention;

[0060] Figure 3 For Figure 2 The front view structural diagram of the non-slip mechanism shown;

[0061] Figure 4 is Figure 2 a partially enlarged schematic view of the fixing component in

[0062] Figure 5 is Figure 2 a top view structural schematic diagram of the anti-slip mechanism shown in

[0063] Figure 6 is Figure 2 a partial structural schematic diagram of the anti-slip mechanism in the second state shown in

[0064] Figure 7 a structural schematic diagram of an anti-impact component in an embodiment of the present invention;

[0065] Figure 8 a structural schematic diagram of a buffer component in an embodiment of the present invention;

[0066] Figure 9 a flowchart of a method for hydraulic fracturing of a coal mine roof in an embodiment of the present invention.

[0067] Reference numerals:

[0068] 100, liquid supply pipeline; 200, hole packer; 300, anti-slip mechanism; 400, energy absorption mechanism; 500, roof; 510, drill hole; 600, drill rig;

[0069] 310, sleeve rod; 312, first elastic member; 314, control button; 316, first end of the sleeve rod; 318, second end of the sleeve rod; 320, sleeve; 322, first mounting hole; 324, opening; 330, collar; 332, support plate; 334, support member; 336, connecting member; 338, hinge; 340, second mounting hole; 352, first limiting member; 354, second limiting member; 356, first buffer member; 410, anti-impact component; 412, third mounting hole; 414, opening; 420, buffer component; 422, connecting portion; 424, main body portion; 426, second elastic member; 428, third limiting member; 432, telescopic rod; 434, third elastic member; 436, fitting portion. Detailed embodiments

[0070] To make the objectives, technical solutions and advantages of the embodiments of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of this application. Apparently, the described embodiments are some, but not all, of the embodiments of this application. It should be noted that, without conflict, the implementation manners and features in the implementation manners in this disclosure may be combined, separated, interchanged and / or rearranged with each other. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in this application without creative efforts shall fall within the protection scope of this application.

[0071] In the drawings, for clarity and / or descriptive purposes, the dimensions and relative dimensions of components may be exaggerated. When the exemplary embodiments may be implemented differently, the specific process sequences may be performed in an order different from that described. For example, two consecutively described processes may be performed substantially simultaneously or in an order opposite to that described. In addition, the same reference numerals denote the same components.

[0072] The terms used herein are for the purpose of describing specific embodiments and are not intended to be limiting. As used herein, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are also intended to include the plural forms. In addition, when the terms "comprise" and / or "include" and their variants are used in this specification, it is indicated that there are the stated features, wholes, steps, operations, components, assemblies and / or groups thereof, but do not exclude the existence or addition of one or more other features, wholes, steps, operations, components, assemblies and / or groups thereof. It should also be noted that, as used herein, the terms "substantially", "about" and other similar terms are used as approximate terms and not as degree terms, so they are used to explain the inherent deviations of measured values, calculated values and / or provided values that those of ordinary skill in the art will recognize.

[0073] It should be noted that the accompanying drawings in this embodiment are schematic diagrams to assist in explaining the concept of the present invention, schematically showing the shapes of various parts and their mutual relationships. It should be understood that, in order to clearly show the structures of the various components of the present invention, the accompanying drawings are not drawn in the same proportion, and the same reference numerals are used to represent the same parts in the drawings.

[0074] As described in the background art, during the process of hydraulic fracturing, there is a problem that the drill pipe is flushed out, which will pose a hazard to the personal safety of construction workers.

[0075] Therefore, to address the above problems, in order to reduce the occurrence probability of such accidents, ensure personal safety, and ensure construction efficiency, a safety energy-absorbing device for hydraulic fracturing of coal mine roof is provided. On the one hand, during the process of supplying liquid through the supply pipeline to the borehole, the anti-slip mechanism is at least connected to the supply pipeline located in the borehole, and the anti-slip mechanism abuts against the inner wall of the borehole, which can provide a supporting force for the supply pipeline, improve the stability of the supply pipeline. Even if the sealing quality is poor or the pressure is too high, the supply pipeline can still work stably, reducing the probability of the supply pipeline recoiling. On the other hand, by setting an energy-absorbing mechanism between the supply pipeline and the inner wall of the roof, when the supply pipeline recoils, a buffering force opposite to the movement direction of the supply pipeline can be provided, reducing the impact caused by the recoil of the supply pipeline, enhancing the safety during the hydraulic fracturing operation of the roof, being able to make full use of the fracturing fluid, improving the fracturing efficiency, and achieving energy conservation.

[0076] See Figure 1 The schematic diagram of the application scenario of a safety energy-absorbing device for hydraulic fracturing of coal mine roof in an embodiment of the present invention shown in Figure 1 As shown, there is a borehole 510 in the roof 500 (i.e., the rock layer or soil layer above the underground coal mining working face), and the safety energy-absorbing device for hydraulic fracturing of coal mine roof can supply fracturing fluid to the roof 500 through the borehole 510.

[0077] More specifically, the safety energy-absorbing device for hydraulic fracturing of coal mine roof may include: a supply pipeline 100, a part of the supply pipeline 100 is located in the borehole 510 on the roof 500, and the supply pipeline 100 has holes (not shown in the figure) for providing a passage for the fracturing fluid to flow; a packer 200, connected to the supply pipeline 100 and located on one side away from the drill opening (i.e., the orifice of the borehole) of the borehole 510, for sealing the non-target fracturing area in the roof 500; an anti-slip mechanism 300, at least connected to the supply pipeline 100 located in the borehole 510, the anti-slip mechanism 300 has a first state, when the anti-slip mechanism 300 is in the first state, the anti-slip mechanism 300 abuts against the inner wall of the borehole 510 to provide a supporting force for the supply pipeline 100; an energy-absorbing mechanism 400, connected to the side of the supply pipeline 100 away from the anti-slip mechanism 300, and the energy-absorbing mechanism 400 abuts against the inner wall of the roof 500, the energy-absorbing mechanism 400 is used to provide a buffering force opposite to the movement direction of the supply pipeline 100 when the supply pipeline 100 rushes out of the borehole 510.

[0078] Wherein, "rushing out" means that when the injection pressure of the fracturing fluid is too high or the packer 200 is damaged, resulting in the backflow of the fracturing fluid, an outward acting force is generated on the supply pipeline 100, causing the supply pipeline 100 to break away from the borehole 510.

[0079] In some embodiments, when conducting hydraulic fracturing in this solution, a roadway is first established in the roof 500, and then a drilling rig 600 is set in the roadway, and the drilling rig 600 is connected to the liquid supply pipeline 100. By Figure 1 performing drilling operations with the shown drilling rig 600, a drill hole 510 to be fractured can be formed in the roof 500, and the liquid supply pipeline 100 can be placed in the drill hole 510.

[0080] Among them, first, for the specific structure and working principle of the drilling rig 600, reference can be made to the description in the existing solution; second, the "inner wall of the roof 500" mentioned in this solution is the "inner wall of the roadway".

[0081] In some embodiments, when performing drilling operations, the drill hole 510 has a preset angle and a set depth, and the inner diameter of the drill hole 510 is larger than the outer diameter of the liquid supply pipeline 100, so as to set and place the anti-slip mechanism 300 at the drill opening of the drill hole 510.

[0082] Among them, the depth of the drill hole 510 refers to: along the extension direction of the liquid supply pipeline 100, the length of the drill hole 510 in the roof 500, and the angle can refer to the included angle between the drill hole 510 and the ground along the extension direction of the liquid supply pipeline 100.

[0083] In some embodiments, the liquid supply pipeline 100 is a hollow structure, and both ends of the liquid supply pipeline 100 have openings. Through this liquid supply pipeline 100, fracturing fluid can be transported to the roof 500.

[0084] More specifically, along the extension direction parallel to the drill hole 510, a through liquid supply path is formed among the liquid supply pipeline 100, the anti-slip mechanism 300, and the energy absorption mechanism 400.

[0085] In some alternative embodiments, the liquid supply pipeline 100 can be a multi-section hollow steel pipe. Among them, for more descriptions about the liquid supply pipeline 100, reference can be made to the existing solution, and this solution does not limit the liquid supply pipeline 100.

[0086] In some embodiments, for different hydraulic fracturing application scenarios, the objects to be fractured are different, and thus different types of fracturing fluids can be provided.

[0087] More specifically, the coal mine roof hydraulic fracturing safety energy absorption device can further include: a plurality of liquid supply devices, and one liquid supply device is used to provide one type of fracturing fluid. Among them, each liquid supply device is connected to the liquid supply pipeline, and the liquid supply paths of each liquid supply device are independent of each other. In this way, at least one of the liquid supply devices can be selected to act according to the object to be fractured (such as the coal seam type) to provide a fracturing fluid adapted to the object to be fractured.

[0088] In some embodiments, the hydraulic fracturing safety energy absorption device for coal mine roof may further include: a processor electrically connected to each liquid supply device, which can output corresponding control signals to the liquid supply device adapted to the fracturing object according to the fracturing object, so as to select and connect the transmission path between the liquid supply device and the liquid supply pipeline.

[0089] For example, a solenoid valve is provided between the liquid supply device and the liquid supply pipeline.

[0090] In some embodiments, the plugging device 200 is connected to the liquid supply pipeline 100 and is located on one side away from the drill opening of the drill hole 510, and can seal the non-target fracturing area in the roof 500, where the non-target fracturing area refers to the area not selected for hydraulic fracturing operation.

[0091] In some embodiments, the liquid supply pipeline 100 is in multiple sections, and the anti-slip mechanism 300 is arranged between any two of them and is fixedly connected to the liquid supply pipeline 100.

[0092] Moreover, the anti-slip mechanism 300 can be in contact with the inner wall of the drill hole 510. In this way, during the fracturing operation, the anti-slip mechanism 300 is embedded into the drill hole 510, which can provide a supporting force for the liquid supply pipeline 100, improve the stability of the liquid supply pipeline 100, and further enhance the safety during the roof hydraulic fracturing operation.

[0093] In some embodiments, the anti-slip mechanism may include: a fixing component, the first end of the fixing component is connected to the liquid supply pipeline located inside the drill hole and near the drill opening, the second end of the fixing component is connected to the liquid supply pipeline located outside the drill hole and is connected to the liquid supply pipeline in a through manner; a sliding component, sleeved on the fixing component and capable of moving along the fixing component; a supporting component, sleeved on the fixing component and located above the sliding component, and the supporting component is also connected to the sliding component.

[0094] More specifically, the fixing component realizes the connection between the liquid supply pipeline and the anti-slip mechanism. In some embodiments, the connection between the fixing component and the liquid supply pipeline is near the drill opening of the drill hole, so that the supporting component can be in contact with the inner wall of the drill hole and is convenient for performing the removal operation.

[0095] The sliding component can move along the fixing component. During the movement of the sliding component along the fixing component, the sliding component can also drive the supporting component to move. When the sliding component moves to a certain position, the postures of the sliding component and the fixing component are fixed and the relative postures no longer change. At this time, the supporting component acts and makes the supporting component in contact with the inner wall of the drill hole, so as to provide sufficient supporting force for the liquid supply pipeline.

[0096] In other words, as the relative pose of the sliding component and the fixed component changes, the relative relationship between the support component and the inner wall of the drill hole will also change, and there is a pose such that the support component abuts against the inner wall of the drill hole.

[0097] More specifically, when the sliding component and the fixed component have a first relative pose, the support component is in the first state and abuts against the inner wall of the drill hole; when the sliding component and the fixed component have a second relative pose, the support component is in the second state.

[0098] Among them, the first state and the second state are different.

[0099] It should be noted that when the support component does not abut against the inner wall of the drill hole, it can be considered that the support component is in the second state, that is, the second state is a set of multiple other states.

[0100] For better illustration and understanding of the working principle and structure of the anti-slip mechanism in this solution, an example is used for illustration.

[0101] See Figures 2 to 6 , where Figure 2 is a schematic structural diagram of an anti-slip mechanism in an embodiment of the present invention, Figure 3 is Figure 2 the front view structural schematic diagram of the anti-slip mechanism shown in Figure 4 is Figure 2 a partial enlarged schematic diagram of the fixed component in Figure 5 is Figure 2 the top view structural schematic diagram of the anti-slip mechanism shown in Figure 6 is Figure 2 a partial structural schematic diagram of the anti-slip mechanism shown in the second state.

[0102] See Figures 2 to 6 , the fixed component may include: a sleeve rod 310, a control button 314 is arranged on the sleeve rod 310, and a first elastic member 312 located inside the sleeve rod 310 and in linkage cooperation with the control button 314.

[0103] Correspondingly, the sliding component may include: a sleeve 320, an opening 324 is arranged on the sleeve 320, the opening 324 is adapted to the control button 314, and when the control button 314 is fixed in the opening 324, the sliding component and the fixed component have the first relative pose.

[0104] Specifically, the sleeve 320 is sleeved on the outer wall of the sleeve rod 310 and can move up and down along the sleeve rod 310. During the movement of the sleeve 320, the control button 314 can drive the first elastic member 312 to move, and the control button 314 can be nested in the opening 324. Under the interaction between the control button 314, the opening 324 and the first elastic member 312, the sleeve 320 stops moving. At this time, the sliding assembly and the fixed assembly have a first relative pose.

[0105] In some embodiments, the first end 316 of the sleeve rod has a first mounting opening, and the inner wall of the first mounting opening is provided with internal threads, while the outer wall of the liquid supply pipe 100 has external threads. Through the threaded connection scheme, the connection between the first end 316 of the sleeve rod and the liquid supply pipe 100 is realized.

[0106] Similarly, the second end 318 of the sleeve rod has a second mounting opening, and the inner wall of the second mounting opening is provided with internal threads, while the outer wall of the liquid supply pipe 100 has external threads. Through the threaded connection scheme, the connection between the second end 318 of the sleeve rod and the liquid supply pipe 100 is realized.

[0107] By means of threaded connection, the operation is simple, and it is convenient to quickly remove and install the anti-slip mechanism.

[0108] It should be noted that the above connection method between the sleeve rod 310 and the liquid supply pipe 100 is only for illustrative purposes. In some other embodiments, it can also be by means of bolt connection.

[0109] In some embodiments, the inner diameter of the sleeve 320 is the same as the outer diameter of the sleeve rod 310. The sleeve 320 can be sleeved on the outer wall of the sleeve rod 310, so that the sleeve 320 can move along the sleeve rod 310 to change the state of the support assembly.

[0110] In some embodiments, when the control button 314 is nested in the opening 324, and since the control button 314 is clamped by the opening 324 and the first elastic member 312 is in a stretched state, the relative pose between the sleeve 320 and the sleeve rod 310 can be maintained when the control button 314 is not touched.

[0111] Correspondingly, when the control button 314 is pressed, the sleeve 320 is no longer restricted by the first elastic member 312, thereby driving the sleeve 320 to move in the opposite direction, and then changing the state of the support assembly, so that the support assembly no longer contacts the inner wall of the drill hole.

[0112] In some examples, the first elastic member 312 can be a spring. In some other embodiments, the first elastic member can also be a rubber member.

[0113] By using the fixed component and the sliding component with the above functional relationship, the state of the support component can be adjusted in real time, and the contact state between the support component and the drilling hole can be changed to adapt to different working processes.

[0114] In some embodiments, one side of the sliding component close to the support component has a first mounting hole 322, and the sliding component is connected to the support component through the first mounting hole 322.

[0115] More specifically, the first mounting hole 322 is arranged on the side of the sleeve 320 away from the control button 314.

[0116] Since the sliding component is connected to the support component through the first mounting hole 322, on the one hand, when the sleeve 320 is not in a moving state, under the action of the support component, the sleeve 320 will not slide off the sleeve rod 310, and when the sleeve 320 is in a moving state, through the first mounting hole 322, the support component can be driven to move, so that the support component abuts against the inner wall of the drilling hole.

[0117] In other words, through the first mounting hole, the interaction mode between the sliding component and the support component changes in different states, improving the stability of the anti-slip structure.

[0118] In some embodiments, the support component can be fixed to the first mounting hole 322 by means of screws.

[0119] In some embodiments, the support component may include: a collar 330 sleeved on the fixed component; a support plate 332 rotatably connected to the collar 330, when the support component is in the first state, the bottom of the support plate 332 faces the outer wall of the fixed component; a support member 334 arranged on the support plate 332, when the support component is in the first state, the support member 334 abuts against the inner wall of the drilling hole 510; a connecting member 336 for connecting the support plate 332 and the sliding component.

[0120] In some embodiments, the inner diameter of the collar 330 is the same as the outer diameter of the sleeve rod 310, and the collar 330 can be sleeved onto the sleeve rod 310 so that the collar 330 can move along the sleeve rod 310.

[0121] In some embodiments, the collar 330 is located on the sleeve 320, so that when the sleeve 320 is in a moving state, the collar 330 can be driven to move.

[0122] In some embodiments, the support plate 332 is rotatably connected to the collar 330, such that the support plate 332 can rotate 180° along the connection between the support plate 332 and the collar 330. This extends the range of motion of the support plate 332, and when the bottom of the support plate 332 faces the outer wall of the sleeve rod 310, the support plate 332 rotates to the maximum angle and remains at this maximum angle, so that the support member 334 can always abut against the inner wall of the drill hole 510.

[0123] In some embodiments, the connecting member 336 realizes the connection between the support plate 332 and the sliding assembly. When the sliding assembly moves, it can drive the connecting member 336 to move, and the other end of the connecting member 336 is connected to the support plate 332, thereby driving the support plate 332 to perform a rotational motion.

[0124] And as can be seen from the foregoing, when the control button 314 is nested in the opening 324, the pose of the sliding assembly is fixed. At this time, the support plate 332 rotates to the maximum angle and remains unchanged, so that the support member 334 can always abut against the inner wall of the drill hole 510.

[0125] In some embodiments, the connecting member 336 has a certain degree of expandability. When the pose of the sliding assembly is fixed, it can make the support plate 332 rotate to the maximum angle and remain unchanged.

[0126] In some alternative embodiments, the connecting member 336 may include a connecting rod or a connecting chain.

[0127] In some embodiments, the more the number of support members, the larger the contact area between the anti-slip mechanism and the inner wall of the drill hole, and thus a greater supporting force can be provided.

[0128] Based on this, in some embodiments, the number of support plates 332 is multiple, and the multiple support plates 332 are symmetrically arranged along the collar 330, and the numbers on both sides are the same.

[0129] Among them, only two support plates 332 are shown in this solution, and one support member 334 is provided on one support plate 332.

[0130] By making the number of support plates 332 multiple, the number of support members 334 can be increased, thereby increasing the contact area with the inner wall of the drill hole and providing a greater supporting force; and the symmetrical arrangement of the support plates 332 along the collar 330 can make the provided supporting force more evenly distributed.

[0131] In other words, the support assembly is symmetrically arranged along the central axis of the fixed assembly.

[0132] In some embodiments, the number of support members can be multiple, and the multiple support members can be arranged on one support plate.

[0133] In other words, by increasing the number of support members on the support plate, the effect of providing greater supporting force can also be achieved.

[0134] In some embodiments, the number of support members is based on the total mass of the liquid supply pipeline 100, the depth L of the borehole 510 in the roof 500, and the inclination angle of the borehole 510 Determined.

[0135] More specifically, first, according to the depth L, the inner diameter and outer diameter of the liquid supply pipeline 100, determine the total weight M of the liquid supply pipeline 100 in the borehole 510:

[0136]

[0137] Where, d 1 is the outer diameter of the liquid supply pipeline 100, m; d 2 is the inner diameter of the liquid supply pipeline 100, m; is the density of the material of the liquid supply pipeline 100, kg / m 3 .

[0138] In an alternative embodiment, if the material of the liquid supply pipeline 100 is steel, then is 7850 kg / m 3 .

[0139] Secondly, according to the total weight M of the liquid supply pipeline 100 and the inclination angle of the borehole 510, calculate the ultimate sliding force F of the liquid supply pipeline 100;

[0140]

[0141] Where, M is the total weight of the liquid supply pipeline, kg; g is the acceleration due to gravity, m / s²; k 1 is the friction coefficient; k 2 is the expansion coefficient of the impact fracturing fluid when providing fracturing fluid; is the inclination angle of the borehole 510, °; L is the depth of the borehole 510 in the roof, m.

[0142] In an alternative embodiment, 0 < k 1 ≤ 1; k 2 is generally 1.0 to 1.5, g = 9.8 m / s².

[0143] Furthermore, according to the calculated ultimate sliding force and the set sliding force, determine the number of support members:

[0144] If 0 < F ≤ 25 KN, the anti-slip mechanism is provided with 1 set of support members (i.e., 2 support members); if 25 < F ≤ 50 KN, the anti-slip mechanism is provided with 2 sets of support foot rods (i.e., 4 support members); if 50 < F ≤ 75 KN, the anti-slip mechanism is provided with 3 sets of support foot rods (i.e., 6 support members).

[0145] In a specific embodiment, if the hydraulic fracturing technology is used for roof pressure relief, the outer diameter of the liquid supply pipeline used for hydraulic fracturing is 73 mm, the inner diameter is 53 mm, the drilling inclination angle is 30°, and the drilling depth is 150 m. According to the above design scheme, M = 2329.3 kg.

[0146] If k 1 is 0.6, k 2 is 1.2, then F = 8.22 KN < 25 KN, and the anti-slip mechanism is provided with 1 set of support members.

[0147] In some embodiments, the included angle between the support plate 332 and the support member 334 is 90 degrees. In this way, when the support plate 332 rotates to the maximum angle and remains unchanged, the contact area between the support member 334 and the inner wall of the drilling hole 510 is the largest, and a greater supporting force can be provided under the condition that other parameters are the same.

[0148] In some embodiments, one side of the surface of the support member 334 away from the support plate 332 has an arc-shaped contact surface 335, and the arc-shaped contact surface 335 is adapted to the outer diameter of the fixing component (such as the sleeve rod 310). In this way, when the reverse flow phenomenon occurs, on the one hand, the contact area between the support member 334 and the inner wall of the drilling hole 510 is reduced, and the impact on the support member 334 is reduced; on the other hand, when the anti-slip structure 300 is removed, by moving the support plate 332, the arc-shaped contact surface 335 can be made opposite to the sleeve rod 310, which reduces the overall volume of the anti-slip structure and is convenient to take out from the drilling hole 510.

[0149] This is because: if the top of the support member 334 is of other shapes (such as square), during the retraction process of the anti-slip structure, both ends of the support member 334 abut against the sleeve rod 310, and there is a region protruding from the sleeve rod 310. Due to the existence of this region, the anti-slip mechanism still has a relatively large width and is not easy to take out from the drilling hole.

[0150] In other words, one side of the surface of the support member 334 away from the support plate 332 is an arc-shaped opening, and the diameter of the arc-shaped opening is the same as the outer diameter of the sleeve rod 310. When the support mechanism is retracted, the support member 334 can fit against the outer wall of the sleeve rod 310, reducing the volume of the anti-slip mechanism.

[0151] In some embodiments, a hinge 338 is provided on the outer wall of the collar 330, and the support plate 332 is rotatably connected to the collar 330 through the hinge 338.

[0152] In an alternative embodiment, the hinge 338 can be a hinge, and for the structure and working principle of the hinge, reference can be made to the descriptions in existing solutions, and this solution places no restrictions thereon.

[0153] In some embodiments, the side of the support plate 332 away from the support member 334 has a second mounting hole 340, and the connecting member 336 passes through the second mounting hole 340 to connect the support plate 332 and the sliding assembly.

[0154] In some embodiments, the connecting member 336 can be fixed in the first mounting hole 322 by means of screws to achieve the connection between the connecting member 336 and the support plate 332.

[0155] In some embodiments, the side of the support member 334 away from the support plate 332 has an anti-slip member, and when the support assembly is in the first state, the anti-slip member abuts against the inner wall of the drilling hole 510.

[0156] By providing the anti-slip member, the friction between the support member 334 and the drilling hole 510 is increased, so that the anti-slip mechanism can be better fixed in the original position, and further, the position of the liquid supply pipeline 100 is relatively fixed to further improve safety. Among them, the anti-slip member can be rubber.

[0157] In some embodiments, the coal mine roof hydraulic fracturing safety energy absorption device may further include: a first limiting member 352, which is arranged on the fixing component and is located above the collar 330.

[0158] More specifically, the first limiting member 352 is arranged on the outer wall of the sleeve rod 310 and is located above the collar 330, and can prevent the collar 330 from detaching from the sleeve rod 310, enhancing the working stability of the anti-slip mechanism.

[0159] In an alternative embodiment, the first limiting member 352 can be a limiting block protruding from the sleeve rod 310.

[0160] In some embodiments, the coal mine roof hydraulic fracturing safety energy absorption device may further include a second limiting member 354, and the second limiting member 354 is arranged on the fixing component and is located between the collar 330 and the sliding assembly.

[0161] More specifically, the second limiting member 354 is arranged on the outer wall of the sleeve rod 310 and is located between the collar 330 and the sleeve 320 to limit the movement range of the collar 330 to further enhance the working stability of the anti-slip mechanism.

[0162] In an alternative embodiment, the second limiting member 354 can be a limiting block protruding from the sleeve rod 310.

[0163] In some embodiments, considering the possible damage that the support component (more specifically, the collar 330) may suffer when moving along the sleeve rod 310, the hydraulic fracturing safety energy absorption device for coal mine roof can further include a first buffer member 356, which is wound around the fixed component and is located between the collar 330 and the second limiting member 354.

[0164] More specifically, the first buffer member 356 is wound around the outer wall of the sleeve rod 310 and is located between the collar 330 and the second limiting member 354. When the collar 330 moves along the sleeve rod 310, the first buffer member 356 can play a buffering and protecting role to reduce the damage to the collar 330.

[0165] In some embodiments, when the hydraulic fracturing safety energy absorption device for coal mine roof includes both the second limiting member 354 and the first buffer member 356, the second limiting member 354 restricts the further downward movement of the first buffer member 356, and the position of the second limiting member 354 on the fixed component is determined by the position of the collar 330 on the fixed component and the length of the first buffer member 356.

[0166] In an alternative embodiment, the first buffer member 356 is a spring.

[0167] In some embodiments, the outer wall of the sleeve rod is provided with inwardly protruding recesses, and the outer wall of the sleeve rod is between adjacent recesses; a clamping portion that is in clamping fit with the recesses to limit the movement of the collar, wherein the clamping portion includes: a body, which is arranged along the circumferential direction of the sleeve rod, and the body has an opening; a clamping member that is arranged in the opening and is connected to the body, and the clamping member is in contact with the recess.

[0168] In other words, through the cooperation between the clamping member and the recess, when the sleeve 320 drives the collar 330 to move, causing the support member 334 to contact the inner wall of the drilling hole, the collar 330 pushes the clamping portion to move, and the clamping portion and the recess are in clamping fit. When the clamping portion reaches one of the recesses, the buffering and limiting effects are achieved, thereby replacing the second limiting member and the first buffer member.

[0169] In some embodiments, when the anti-slip mechanism is in the initial state, the control button 314 is not clamped at the opening 324, and at this time, the support member 334 does not contact the inner wall of the drilling hole 510.

[0170] When the anti-slip mechanism is in the working state, it drives the sleeve 320 to move towards the position where the control button 314 is located. When the sleeve 320 drives the bottom of the support plate 332 to move towards the sleeve rod 310 through the connecting member 336, during this process, the support member 334 gradually approaches the inner wall of the drilling hole 510.

[0171] When the opening 324 on the sleeve 320 moves to the control button 314, the control button 314 is fixed at the opening 324, and the sleeve 320 stops moving. At this time, the support plate 332 rotates to the maximum angle and remains unchanged, so that the support member 334 can always abut against the inner wall of the drill hole 510, thereby realizing clamping.

[0172] When it is necessary to remove the anti-slip mechanism, press the control button 314, and the sleeve 320 moves toward the side away from the control button 314, so that the support member 334 does not abut against the inner wall of the drill hole 510, and the anti-slip mechanism can be taken out.

[0173] In some embodiments, the inventor further found that if the reverse impact force is large, there is a possibility that the anti-slip mechanism fails, and the liquid supply pipeline will rush out of the drill hole.

[0174] In this embodiment, one side of the energy absorption mechanism 400 abuts against the inner wall of the top plate 500, and the position of the energy absorption mechanism 400 is relatively fixed. When the liquid supply pipeline 100 rushes out of the drill hole (i.e., when it rushes out) and contacts the energy absorption mechanism 400, the energy absorption mechanism 400 can provide a buffering force opposite to the movement direction of the liquid supply pipeline 100, reducing the impact caused by the liquid supply pipeline 100 rushing out, so as to further improve the safety during the hydraulic fracturing operation.

[0175] In some embodiments, the energy absorption mechanism 400 can be connected to the liquid supply pipeline 100 through the drill truck 600.

[0176] In some embodiments, there is a link mechanism between the energy absorption mechanism 400 and the anti-slip mechanism 300, and the two ends of the link are respectively connected to the energy absorption mechanism 400 and the anti-slip mechanism 300. When the support rod in the anti-slip mechanism 300 slides, the link mechanism will pull or push the starting mechanism of the energy absorption mechanism 400, so that the energy absorption mechanism 400 acts in advance.

[0177] In short, through the linkage cooperation between the energy absorption mechanism 400 and the anti-slip mechanism 300, the safety during the hydraulic fracturing operation can be further improved.

[0178] In some embodiments, referring to Figure 7 and Figure 8 the structural schematic diagram of the energy absorption mechanism in an embodiment of the present invention shown, the energy absorption mechanism 400 may include: an anti-impact component 410, one side of the anti-impact component 410 has a third mounting hole 412, the side of the anti-impact component 410 facing away from the third mounting hole 412 has a through channel (not shown in the figure) connected to the liquid supply pipeline 100 and offset from the third mounting hole 412, and an opening 414 communicated with the through channel and located inside the anti-impact component 410, and the orifice of the opening 414 is located at the bottom of the anti-impact component 410.

[0179] More specifically, the impact prevention component 410 is a metal block. On one side of the metal block, six third mounting holes 412 are provided, and the third mounting holes 412 are arranged in a 3×2 pattern. The interior of the third mounting holes 412 has a threaded structure for connection with the buffer component 420.

[0180] On the side of the impact prevention component 410 facing the liquid supply pipe 100, a through-channel is provided. The through-channel is set based on the inclination degree of the liquid supply pipe 100, and the through-channel has threads inside for connection with the liquid supply pipe 100.

[0181] At the bottom of the impact prevention component 410, there is an opening 414 with a certain depth, and the opening 414 is in communication with the through-channel. During the hydraulic fracturing operation, the liquid supply water pipe of the liquid supply equipment (such as Figure 1 the water pipe protruding from the energy absorption mechanism 400 as shown) is connected to the opening 414 of the impact prevention component 410, and through the through-channel inside the impact prevention component 410, the delivery of the fracturing fluid is realized.

[0182] In some embodiments, a hydraulically adjustable lifting foot is designed at the bottom of the impact prevention component 410 to better adapt to the actual working conditions and facilitate the connection with the liquid supply steel pipe.

[0183] The buffer component 420 is arranged between the impact prevention component 410 and the inner wall of the top plate 500. The first end of the buffer component 420 is connected to the third mounting hole 412, and the second end of the buffer component 420 is used to abut against the inner wall of the top plate 500, and is used to provide the buffer force when the liquid supply pipe 100 bursts out from the drilling hole 510. Among them, the number of the buffer components 420 is determined based on the total mass of the liquid supply pipe 100, the depth L of the drilling hole 510 in the top plate, and the inclination angle of the drilling hole Determined.

[0184] Among them, for the determination method of the buffer component 420, reference can be made to the description of the foregoing examples.

[0185] More specifically, if 0 < F ≤ 50 KN, 2 buffer components 420 are set; if 50 < F ≤ 75 KN, 4 buffer components 420 are set; if 75 < F ≤ 100 KN, 6 buffer components 420 are set.

[0186] In some embodiments, the buffer assembly 420 may include: a connecting portion 422 connected to the third mounting hole 412; a main body portion 424 having a hollow channel and connected to the connecting portion 422; a second elastic member 426 suspended in the hollow channel; a third limiting member 428 disposed on the inner wall of the main body portion 424 and below the second elastic member 426; a telescopic rod 432, the first end of the telescopic rod 432 being above the third limiting member 428 in the hollow channel and capable of compressing the second elastic member 426; and a third elastic member 434 wound around the telescopic rod 432.

[0187] Specifically, when the liquid supply pipe 100 breaks through, the energy absorption mechanism 400 and the liquid supply pipe 100 are connected together. Thus, under the action of the mutual acting force, since the second end of the telescopic rod 432 contacts the inner wall of the top plate 500, the telescopic rod 432 will move toward the side away from the inner wall of the top plate 500. Since a part of the telescopic rod 432 is located inside the main body portion 424, the compression of the second elastic member 426 can be realized.

[0188] Meanwhile, the third elastic member 434 on the telescopic rod 432 will move along with the telescopic rod 432. When the third elastic member 434 is continuously compressed until it contacts the third limiting member 428, the offset of energy is realized.

[0189] In some embodiments, one end of the third elastic member 434 is connected to the telescopic rod 432, and the other end of the third elastic member 434 is connected to the third limiting member 428.

[0190] In some embodiments, the third elastic member 434 may be a spring. In some other embodiments, the third elastic member may also be a rubber member.

[0191] In some embodiments, the third limiting member 428 may be a limiting block protruding from the inner wall of the main body portion 424.

[0192] In some embodiments, a fitting portion 436 is further provided at the second end of the telescopic rod 432. By providing the fitting portion 436, the contact area between the telescopic rod 432 and the inner wall of the top plate 500 is increased, and the working stability of the telescopic rod 432 is further improved. Among them, the fitting portion 436 may be rubber.

[0193] In summary, by providing the anti-slip mechanism and / or the energy absorption mechanism, the safety during the hydraulic fracturing operation can be improved.

[0194] The present invention also provides a method for hydraulic fracturing of a coal mine roof, using the safety energy absorption device for hydraulic fracturing of a coal mine roof described in any of the above examples. The operation process of the method for hydraulic fracturing of a coal mine roof is as Figure 9 shown. The method for hydraulic fracturing of a coal mine roof includes the following steps:

[0195] S10, drill holes in the roof slab.

[0196] Among them, the specific method of drilling holes can refer to the description of the existing solution. The focus of this application is to improve the operation safety by setting up an anti-slip mechanism and an energy-absorbing mechanism.

[0197] S20, at least arrange a liquid supply pipeline in the drill hole. The liquid supply pipeline has holes for providing a passage for the fracturing fluid to flow.

[0198] Among them, the liquid supply pipeline is of a hollow structure, and both ends of the liquid supply pipeline have openings. Through this liquid supply pipeline, the fracturing fluid can be transported to the roof slab.

[0199] S30, arrange a hole sealer on one side of the drill opening far from the drill hole. The hole sealer is connected to the liquid supply pipeline for closing the non-target fracturing area in the roof slab.

[0200] S40, provide an anti-slip mechanism. The anti-slip mechanism is at least connected to the liquid supply pipeline located in the drill hole, and the anti-slip mechanism is in a first state to abut against the inner wall of the drill hole to provide a supporting force for the liquid supply pipeline.

[0201] Among them, the anti-slip mechanism can be the anti-slip mechanism described in any of the foregoing examples.

[0202] In some embodiments, the liquid supply steel pipe is connected to the hole sealer. When the liquid supply steel pipe is connected near the drill hole opening, the anti-slip mechanism is installed, and the anti-slip mechanism can be stuck to the hole wall when it is opened near the hole opening inside the drill hole to prevent the liquid supply steel pipe from vibrating or displacing, providing an anti-slip function.

[0203] In some embodiments, step S40 may specifically include: connecting the first end of the fixing component to the liquid supply pipeline located in the drill hole, and connecting the second end of the fixing component to the liquid supply pipeline located outside the drill hole, so that the fixing component is arranged in a penetrating manner with the liquid supply pipeline; driving the sliding component to move along the fixing component, so that the sliding component and the fixing component have a first relative pose, so that the supporting component connected to the sliding component abuts against the inner wall of the drill hole.

[0204] The fixing component realizes the connection between the liquid supply pipeline and the anti-slip mechanism. In some embodiments, the connection between the fixing component and the liquid supply pipeline is located near the drill opening of the drill hole, so that the supporting component can abut against the inner wall of the drill hole.

[0205] The sliding assembly can move along the fixed assembly, and as it does so, it also drives the support assembly. When the sliding assembly reaches one position, the sliding and fixed assemblies are fixed in position, their relative positions no longer changing. At this point, the support assembly activates, ensuring contact with the inner wall of the drilled hole, providing sufficient support for the liquid supply pipe.

[0206] In other words, as the relative positions of the sliding component and the fixing component change, the relative relationship between the supporting component and the inner wall of the borehole will also change, and there is one position in which the supporting component conflicts with the inner wall of the borehole.

[0207] S50, provide an energy absorbing mechanism and connect it to the side of the liquid supply pipe away from the anti-slip mechanism, and make the energy absorbing mechanism conflict with the inner wall of the top plate, the energy absorbing mechanism is used to provide a buffering force opposite to the movement direction of the liquid supply pipe when the liquid supply pipe rushes out of the drill hole.

[0208] The energy absorbing mechanism may be any of the energy absorbing mechanisms described in the foregoing examples.

[0209] S60: Supply the fracturing fluid to the fluid supply pipeline through the anti-slip mechanism and the energy absorbing mechanism.

[0210] In some embodiments, the anti-slip mechanism and the energy absorbing mechanism are connected to the liquid supply pipeline, and fracturing fluid can be provided to the liquid supply pipeline through the anti-slip mechanism and the energy absorbing mechanism.

[0211] In other words, the anti-slip mechanism and the energy absorbing mechanism can be part of the liquid supply pipeline.

[0212] In some embodiments, the step of driving the sliding assembly to move along the fixed assembly so that the sliding assembly and the fixed assembly have a first relative posture includes:

[0213] The support plate 332 is rotatably connected to the collar 330 , a second mounting hole 340 is provided on a side of the support plate 332 facing the fixing assembly, and a support member 334 is provided on the support plate 332 .

[0214] The sleeve ring 330 is sleeved on the sleeve rod 310 . The sleeve rod 310 is provided with a control button 314 . A first elastic member 312 that cooperates with the control button 314 is provided inside the sleeve rod 310 .

[0215] Sheath the sleeve 320 on the sleeve rod 310. The sleeve 320 is located below the sleeve rod 310, and a first mounting hole 322 is provided on one side of the sleeve 320 close to the sleeve rod 310. Moreover, there is an opening 324 on the sleeve 320, and the opening 324 is located below the first mounting hole 322.

[0216] Connect the sleeve 320 and the support plate 332 through a connecting member 336.

[0217] Drive the sleeve 320 to move along the sleeve rod 310 until the control button 314 is fixed in the opening 324 and the support member 334 abuts against the inner wall of the drilling hole 510.

[0218] In some alternative embodiments, if the coal mine roof hydraulic fracturing safety energy absorption device further includes an energy absorption mechanism, the coal mine roof hydraulic fracturing method may further include:

[0219] Install the energy absorption mechanism, including: determining the interface angle of the impact prevention component, where the interface angle is determined based on the drilling inclination angle and roadway conditions; installing buffer components on the side of the impact prevention component close to the roadway wall. The buffer components need to be arranged symmetrically, and the number of buffer components is determined based on the total mass of the liquid supply pipeline, the depth of the drilling hole in the roof, and the inclination angle of the drilling hole; connect the liquid supply steel pipe to the impact prevention component and make the buffer components abut against the roadway wall.

[0220] In some alternative embodiments, when it is necessary to remove the anti-slip mechanism, trigger the control button, and the sleeve 320 will slide upward along the sleeve rod 310, causing the support member 334 to become loose and disengage from the inner wall of the drilling hole 510.

[0221] The specific embodiments described above further elaborate on the purpose, technical solutions, and beneficial effects of the present application. It should be understood that the above are only specific embodiments of the present application and are not used to limit the protection scope of the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application shall be included within the protection scope of the present application.

Claims

1. A safety energy absorption device for hydraulic fracturing of coal mine roof, characterized in that include: a fluid supply pipe, a portion of which is located in the borehole on the top plate, the fluid supply pipe having a hole therein for providing a passage for the fracturing fluid to flow; a hole sealer connected to the fluid supply pipeline and located on a side away from the drill opening of the borehole, for sealing a non-target fracturing area in the top plate; an anti-slip mechanism connected to at least the liquid supply pipe located in the borehole, the anti-slip mechanism having a first state. When the anti-slip mechanism is in the first state, the anti-slip mechanism contacts the inner wall of the borehole to provide support for the liquid supply pipe; an energy absorbing mechanism connected to a side of the liquid supply pipe away from the anti-slip mechanism, and the energy absorbing mechanism abuts against an inner wall of the top plate, the energy absorbing mechanism being configured to provide a buffering force in a direction opposite to the movement direction of the liquid supply pipe when the liquid supply pipe rushes out of the drilled hole; The anti-slip mechanism comprises: a fixing assembly, wherein a first end of the fixing assembly is connected to a liquid supply pipe located in the borehole and near the drill opening, and a second end of the fixing assembly is connected to the liquid supply pipe located outside the borehole and is in continuous communication with the liquid supply pipe; A sliding component is sleeved on the fixed component and can move along the fixed component; A support assembly is sleeved on the fixed assembly and located above the sliding assembly, and the support assembly is also connected to the sliding assembly; When the sliding assembly and the fixed assembly have a first relative posture, the support assembly is in the first state, and the support assembly is in conflict with the inner wall of the borehole; when the sliding assembly and the fixed assembly have a second relative posture, the support assembly is in a second state, and the first state and the second state are different; The fixing assembly includes: a sleeve rod, a control button is provided on the sleeve rod, and a first elastic member located in the sleeve rod and linked with the control button; The sliding assembly includes: a sleeve, the sleeve is provided with an opening, the opening is adapted to the control button, and when the control button is fixed in the opening, the sliding assembly and the fixing assembly have the first relative posture; The support assembly comprises: A collar, sleeved on the fixing assembly; a support plate rotatably connected to the collar, wherein the support assembly is in the first state, and a bottom of the support plate is opposite to an outer wall of the fixing assembly; a support member disposed on the support plate, wherein when the support assembly is in the first state, the support member contacts the inner wall of the drill hole; A connecting piece is used to connect the support plate and the sliding assembly.

2. The hydraulic fracturing safety energy absorption device for coal mine roof according to claim 1, wherein, The sliding component has a first mounting hole on one side close to the supporting component, and the sliding component is connected to the supporting component through the first mounting hole.

3. The hydraulic fracturing safety energy absorption device for coal mine roof according to claim 1, wherein There are multiple support plates, and the multiple support plates are symmetrically arranged along the ring, and the number of support plates on both sides is the same; There are multiple support members, and multiple support members can be set on one support plate, wherein the number of the support members is determined based on the total mass of the liquid supply pipeline, the depth of the drill hole in the top plate, and the inclination angle of the drill hole; One side of the support member away from the support plate has an arc-shaped contact surface, and the arc-shaped contact surface is adapted to the outer diameter of the fixing component; The included angle between the support plate and the support member is 90 degrees; A hinge is provided on the outer wall of the collar, and the support plate is rotatably connected to the collar through the hinge; One side of the support plate away from the support member has a second mounting hole, and the connecting member connects the support plate and the sliding component through the second mounting hole; The connecting member includes a connecting rod or a connecting chain.

4. The hydraulic fracturing safety energy absorption device for coal mine roof according to claim 1, characterized in that, One side of the support member away from the support plate has an anti-slip member, and when the support assembly is in the first state, the anti-slip member abuts against the inner wall of the drilling hole; The first limiting member is arranged on the fixing component and is located above the collar; The second limiting member is arranged on the fixing component and is located between the collar and the sliding component; The first buffer member is wound around the fixing component and is located between the collar and the second limiting member; Wherein, the position of the second limiting member on the fixing component is determined by the position of the collar on the fixing component and the length of the first buffer member.

5. The hydraulic fracturing safety energy absorption device for coal mine roof according to claim 1, characterized in that, The energy absorption mechanism includes: An anti-impact component, one side of the anti-impact component has a third mounting hole, the side of the anti-impact component facing away from the third mounting hole has a through-channel connected to the liquid supply pipeline and offset from the third mounting hole, and an opening hole communicated with the through-channel and located inside the anti-impact component, and the orifice of the opening hole is located at the bottom of the anti-impact component; A buffer component is arranged between the anti-impact component and the inner wall of the top plate. The first end of the buffer component is connected to the third mounting hole, and the second end of the buffer component is used to abut against the inner wall of the top plate to provide the buffer force when the liquid supply pipeline rushes out of the drilling hole. Wherein, the number of the buffer components is determined based on the total mass of the liquid supply pipeline, the depth of the drilling hole in the top plate, and the inclination angle of the drilling hole.

6. The hydraulic fracturing safety energy absorption device for coal mine roof according to claim 5, characterized in that, The buffer component includes: A connecting portion connected to the third mounting hole; A main body portion having a hollow channel and connected to the connecting portion; A second elastic member is suspended in the hollow channel; A third limiting member arranged on the main body portion and located below the second elastic member; A telescopic rod, the first end of the telescopic rod is located above the third limiting member in the hollow channel and can compress the second elastic member; A third elastic member wound around the telescopic rod.

7. A hydraulic fracturing method for a coal mine roof, which is applied to the hydraulic fracturing safety energy absorption device for a coal mine roof described in any one of claims 1 to 6, and is characterized in that, The hydraulic fracturing method includes: Constructing a drilling hole in the top plate; At least arranging a liquid supply pipeline in the drilling hole, and the liquid supply pipeline has holes for providing a passage for the fracturing fluid to flow; A hole plugging device is arranged on one side of the drill opening away from the drilling hole, and the hole plugging device is connected to the liquid supply pipeline for closing the non-target fracturing area in the top plate; Providing an anti-slip mechanism, the anti-slip mechanism is at least connected to the liquid supply pipeline located in the drilling hole, and the anti-slip mechanism is in the first state to abut against the inner wall of the drilling hole to provide a supporting force for the liquid supply pipeline; An energy absorption mechanism is provided and connected to a side of the liquid supply pipeline away from the anti-slip mechanism, and the energy absorption mechanism is in contact with the inner wall of the top plate. The energy absorption mechanism is used to provide a buffering force opposite to the movement direction of the liquid supply pipeline when the liquid supply pipeline bursts out from the drilling hole; Through the anti-slip mechanism and the energy absorption mechanism, the fracturing fluid is provided to the liquid supply pipeline.

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