A working face grouting reinforcement device

Abstract

The utility model discloses a working face grouting reinforcement device, still include center grouting pipe, controller and a plurality of flexible bag, and the bottom of center grouting pipe is equipped with sealing cover, and center grouting pipe is equipped with non -return air vent, a plurality of flexible bag are set in the outer wall of center grouting pipe, and along the axial interval arrangement of center grouting pipe, every flexible bag with center grouting pipe all is provided with controllable valve group, and the import end of controllable valve group communicates with center grouting pipe, and the export end of controllable valve group communicates with flexible bag, and controller is electrically connected with controllable valve group, is used for the opening and closing of independent control every controllable valve group, can according to the geological condition of different hole section in drilling and carry out sequencing grouting, and flexible bag completely physical isolation slurry and the fissure etc. defect in formation, prevent grouting when along the fissure and need not diffuse, form effective support body in target area, improve the support effect.

Description

Technical Field

[0001] This utility model relates to the field of mining construction technology, specifically to a grouting reinforcement device for working faces. Background Technology

[0002] my country's fossil energy is mainly coal. The geological structure of Chinese coal mines is characterized by "dense fractures and folds, and a weak and broken roof," which becomes increasingly complex with increasing mining depth. This makes them highly susceptible to geological disasters such as anchoring, water inrush, and sand collapse. To ensure safe tunneling, it is necessary to rapidly reinforce defective areas, roof cavities, and interlayer voids in the working face to form a load-bearing curtain. The traditional approach involves drilling directly along the contour after revealing the defects, connecting the grouting pump to the grouting pipe, and inserting the pipe into the borehole to begin grouting from the bottom. When the self-stabilizing capacity of the grouting area is weak, splitting, grout leakage, and grout runoff easily occur. The grout spreads disorderly along the fractures, failing to form an effective support structure in the target area or resulting in a poorly supported structure. Summary of the Invention

[0003] This utility model provides a grouting reinforcement device for working faces, which can solve the above-mentioned technical problems.

[0004] This utility model is achieved through the following technical solution: A grouting reinforcement device for working faces also includes a central grouting pipe, a controller, and multiple flexible bags. The bottom end of the central grouting pipe is equipped with a sealing cap, and the central grouting pipe is equipped with a one-way exhaust valve; Multiple flexible bags are fitted onto the outer wall of the central grouting pipe and spaced apart along the axial direction of the central grouting pipe; Each of the flexible bags is provided with a controllable valve group between it and the central grouting pipe. The inlet end of the controllable valve group is connected to the central grouting pipe, and the outlet end of the controllable valve group is connected to the flexible bag. The controller is electrically connected to the controllable valve group and is used to independently control the opening and closing of each controllable valve group.

[0005] Furthermore, it also includes a pressure sensor that monitors the filling pressure within the flexible pouch, the pressure sensor being electrically connected to the controller.

[0006] Furthermore, after grouting, the multiple flexible bags form discretely distributed supports within the borehole.

[0007] Furthermore, the flexible bag is an annular cylindrical structure, the inner diameter of the flexible bag is smaller than the outer diameter of the central grouting pipe, and the central grouting pipe is provided with positioning rings on both sides of the flexible bag to restrict the displacement of the flexible bag.

[0008] Furthermore, the controllable valve assembly includes a connecting pipe connecting the flexible bladder and the central grouting pipe, as well as a flow sensor and a solenoid valve connected to the controller.

[0009] Furthermore, the inner wall of the inlet of the flexible bag is connected to a rigid inner sleeve and locked by a locking clamp. The rigid inner sleeve is snapped into the connecting tube, and a sealing ring is provided at the joint surface between the rigid inner sleeve and the connecting tube.

[0010] Furthermore, the sealing cap is fixedly or detachably connected to the bottom of the central grouting pipe.

[0011] Compared with the prior art, this utility model has the following advantages and beneficial effects: A grouting reinforcement device for a working face includes a central grouting pipe, a controller, and multiple flexible bladders. During operation, the central grouting pipe is inserted into the borehole, with its open end connected to the grouting end of a grouting pump. Grout is delivered through the central grouting pipe under pump pressure. Air inside the central grouting pipe is discharged through a one-way exhaust valve. The controller then opens the valve of one of the controllable valve groups, allowing grout to enter the corresponding flexible bladder. Once a flow sensor detects that the flexible bladder has reached a preset grouting volume, the controller closes the valve of that controllable valve group and opens the valve of the next controllable valve group to grout the next flexible bladder. This cycle continues until all bladders are grouting. In the grouting operation of flexible grouting bags, the flexible grouting bags expand under the constraint of the borehole, filling the annular space of the borehole. The grout solidifies inside the flexible grouting bags, forming an integral, high-strength composite support with the central grouting pipe and the flexible grouting bags. This effectively reinforces the fractured surrounding rock and cavities in the strata. Thus, the opening sequence of the controllable valve group is controlled by the controller, and grouting is performed in sequence as needed, such as grouting from the middle to the two ends or from the two ends to the rear ends. The flexible grouting bags completely physically isolate the grout from the fissures and other defects in the strata, effectively preventing the disorderly diffusion of the grout along the fissures during grouting. This forms an effective support in the target area, improving the support effect. Attached Figure Description

[0012] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present invention and form part of this application, do not constitute a limitation thereof. In the drawings: Figure 1 This is a schematic diagram of the structure of a grouting reinforcement device for a working face according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the structure of the central grouting pipe in an embodiment of the present invention; Figure 3 This is a schematic diagram of the connection between the flexible bag and the controllable valve assembly in an embodiment of this utility model.

[0013] The attached diagram shows the markings and corresponding component names: 10-Grouting pump, 11-Central grouting pipe, 111-Sealing cap, 1111-One-way exhaust valve, 112-Positioning ring, 12-Flexible bladder, 121-Rigid inner liner, 122-Locking clamp, 13-Solenoid valve, 14-Controller, 15-Flow sensor, 16-Pressure sensor, 17-Connecting pipe. Detailed Implementation

[0014] The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the scope of the present invention.

[0015] In this embodiment of the invention, the terms "system" and "network" can be used interchangeably. "Multiple" refers to two or more; therefore, in this embodiment, "multiple" can also be understood as "at least two." "And / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A alone, A and B simultaneously, or B alone. Additionally, the character " / ", unless otherwise specified, generally indicates that the preceding and following related objects have an "or" relationship. Furthermore, it should be understood that in the description of this embodiment of the invention, words such as "first" and "second" are used only for descriptive purposes and should not be construed as indicating or implying relative importance or order.

[0016] As described in the background section, when traditional grouting pipes are used for jet grouting at the working face, grouting begins from the bottom of the borehole after the grouting pipe is inserted. When the self-stabilizing ability of the grouting area is weak, splitting, cross-contamination, and grout leakage are likely to occur. The grout spreads disorderly along the cracks, and the support structure formed in the target area has a poor support effect. Once it cannot provide effective support, it will cause serious safety accidents.

[0017] Based on this, the inventors created a working face grouting reinforcement device according to this application to solve the above-mentioned technical problems. Example

[0018] Please see Figures 1-3A grouting reinforcement device for working faces includes a central grouting pipe 11, a controller 14, and multiple flexible bags 12 (the flexible bags 12 shown in the figure are in an un-grouted state). The central grouting pipe 11 is a hollow pipe body, which can be a seamless steel pipe integrally formed or a steel pipe rolled and welded. It is preferred to be a seamless steel pipe integrally formed, without welds, with a uniform overall structure, no weak links, higher structural strength and sealing reliability, and more suitable for high-pressure grouting conditions in coal mines. The bottom end of the central grouting pipe 11 is provided with a sealing cap 111. The sealing cap 111 is fixedly connected to the central grouting pipe 11 or detachably connected. The fixed connection is made by welding, which is simple in structure, low in cost, and has high structural strength. The detachable connection is a threaded connection, preferably a tapered pipe threaded connection, which is suitable for high-pressure grouting conditions in coal mines that require high sealing. The detachable connection improves the applicability of this device. The central grouting pipe 11 is provided with a one-way exhaust valve 1111, for example, the one-way exhaust valve 1111 is set on the sealing cap 111.

[0019] Multiple flexible bags 12 are fitted onto the outer wall of the central grouting pipe 11 and spaced apart along the axial direction of the central grouting pipe 11. For example, the flexible bags 12 can be made of rubber and have an annular cylindrical structure. The inner diameter of the flexible bags 12 is smaller than the outer diameter of the central grouting pipe 11. They are tightly wrapped around the outer wall of the central grouting pipe 11 using the elasticity of the material. The structure is simple. After grouting, the flexible bags and the central grouting pipe together form a support body for supporting the borehole. Preferably, after grouting, the multiple flexible bags 12 form a discretely distributed support body in the borehole. That is, after the flexible bags 12 are grouted, there are still gaps between the expanded flexible bags 12. A series of independent support bodies separated by gaps in the axial direction are formed in the borehole. Compared with continuous support bodies, this can provide effective support while reducing the use of grout, reducing costs and construction time. The gaps allow the rock strata to have a certain degree of deformation or stress adjustment, avoiding excessive support that leads to local stress concentration. The central grouting pipe 11 is provided with positioning rings 112 on both sides of the flexible bag 12 to limit the axial displacement of the flexible bag 12, further limiting the flexible bag 12, preventing the flexible bag 12 from axially displacing under grouting pressure, maintaining the spacing between the flexible bags 12, and guiding the expansion of the flexible bag 12 to the radial direction.

[0020] Each flexible bladder is equipped with a controllable valve assembly between itself and the central grouting pipe. The inlet end of the controllable valve assembly is connected to the central grouting pipe, and the outlet end of the controllable valve assembly is connected to the flexible bladder. The number of controllable valve assemblies is the same as that of the flexible bladders 12. A one-way valve can be installed on the outlet side of the controllable valve assembly to prevent slurry backflow. The controllable valve assembly includes a flow sensor 15 and a solenoid valve 13 connected to the controller 14. The flow sensor 15 is used to monitor the slurry flow rate in real time.

[0021] The controller 14 (it should be noted that the controller 14 is existing technology and will not be described in detail here) is electrically connected to multiple controllable valve groups for independently controlling the opening and closing of each controllable valve group. The input terminal of the controller 14 is connected to the flow sensor 15, and the output terminal of the controller 14 is connected to the solenoid valve 13.

[0022] During operation, the central grouting pipe 11 is inserted into the borehole. The open end of the central grouting pipe 11 is connected to the grouting end of the grouting pump (not shown in the figure) 10. The grout is delivered through the central grouting pipe 11 under pump pressure. After the air in the central grouting pipe 11 is discharged through the one-way exhaust valve 1111, the controller 14 opens the valve of one of the controllable valve groups, and the grout enters the corresponding flexible bag 12. After the flow sensor 15 detects that the flexible bag 12 has reached the preset grouting volume, the controller 14 closes the valve of that controllable valve group and opens the valve of the next controllable valve group to grout the next flexible bag. This cycle continues until all flexible bags 12 are grouted. During grouting, the flexible bag 12 expands under the constraint of the borehole, filling the annular space of the borehole. The grout solidifies inside the flexible bag 12, forming an integral, high-strength composite support with the central grouting pipe 11 and the flexible bag 12. This effectively reinforces the fractured surrounding rock and cavities in the strata. Thus, under the control of the controller 14, the opening sequence of the controllable valve group is controlled, and grouting is performed in sequence as needed, for example, grouting from the middle to the two ends or from the two ends to the rear ends. The flexible bag 12 completely physically isolates the grout from the fissures and other defects in the strata, effectively preventing the grout from spreading disorderly along the fissures during grouting. This forms an effective support in the target area, improving the support effect.

[0023] In actual use, due to the complex lithology and uneven hardness of the formation within the same borehole, when the grouting volume of each flexible bag 12 is the same, the resulting support body provides weaker support for the soft formation section within the borehole compared to the hard formation section.

[0024] In this embodiment of the invention, a pressure sensor 16 is also included to monitor the filling pressure inside the flexible bag 12. The pressure sensor 16 is electrically connected to the input terminal of the controller 14 and is disposed on the connection channel between the valve of the controllable valve assembly and the flexible bag 12.

[0025] During operation, one of the controllable valve groups is opened under the action of controller 14 to perform grouting. Pressure sensor 16 monitors the filling pressure inside the flexible bag 12 in real time. When the bag expands to fully contact the borehole wall, if the grouting pump 10 continues to pump grout, the volume inside the bag cannot continue to increase rapidly, resulting in a significant increase in pressure. When pressure sensor 16 detects that the pressure value changes from a steady rise to a rapid surge and reaches a preset value, it indicates that the flexible bag 12 has provided sufficient support for the corresponding formation section. Under the action of controller 14, the controllable valve group is closed, and the next controllable valve group is opened to grout the next flexible bag 12, improving the automation control of the grouting process. Using the pressure value as the grouting termination standard, it can provide effective support for formation sections with different conditions in the same borehole.

[0026] In actual use, when the flexible bladder 12 is filled with high-pressure grout and expands radially, the flexible bladder 12 will be stretched radially and contracted axially accordingly. This can easily cause damage to the connection between the flexible bladder 12 and the controllable valve assembly, leading to grouting failure.

[0027] In this embodiment of the utility model, the inner wall of the inlet of the flexible bag 12 is connected to a rigid inner sleeve 121 and locked by a locking clamp 122 (not shown in the figure). The rigid inner sleeve 121 is snapped into the connecting tube 17, and a sealing ring is provided on the mating surface of the rigid inner sleeve 121 and the connecting tube 17.

[0028] In one possible embodiment, the rigid inner sleeve 121 is a short metal tube with an outer flange at one end. The outer wall of the rigid inner sleeve 121 is integrally bonded to the inside of the inlet of the flexible bag 12 and locked by a locking clamp 122. For example, the locking clamp is a hose clamp connected to one side of the outer flange. The connecting pipe 17 is a short metal pipe with a sealing groove. During installation, the sealing ring is placed in the sealing groove of the short metal pipe, and the rigid inner sleeve 121 is fitted onto the short metal pipe and snapped together. The locking clamp 122 is tightened on one side of the outer flange. The radial force of the locking clamp further compresses the sealing ring and works in conjunction with the snap-fit ​​structure to effectively resist the axial tensile force and internal pressure generated during grouting, preventing the connection from detaching or leaking.

[0029] In this embodiment of the invention, the inner wall of the flexible pouch 12 is bonded with axial fibers (such as nylon or polyester fibers) to suppress axial contraction, prevent damage to the connection, and maintain radial expansion capacity.

[0030] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A grouting reinforcement device for working faces, characterized in that, It also includes a central grouting pipe, a controller, and multiple flexible bladders. The bottom end of the central grouting pipe is equipped with a sealing cap, and the central grouting pipe is equipped with a one-way exhaust valve; Multiple flexible bags are fitted onto the outer wall of the central grouting pipe and spaced apart along the axial direction of the central grouting pipe; a controllable valve group is provided between each flexible bag and the central grouting pipe, the inlet end of the controllable valve group is connected to the central grouting pipe, and the outlet end of the controllable valve group is connected to the flexible bag; The controller is electrically connected to the controllable valve group and is used to independently control the opening and closing of each controllable valve group.

2. The grouting reinforcement device for the working face according to claim 1, characterized in that, It also includes a pressure sensor that monitors the filling pressure within the flexible pouch, the pressure sensor being electrically connected to the controller.

3. The grouting reinforcement device for the working face according to claim 2, characterized in that, After grouting, the multiple flexible bags form discretely distributed supports within the borehole.

4. The grouting reinforcement device for the working face according to claim 3, characterized in that, The flexible bladder has an annular cylindrical structure. The inner diameter of the flexible bladder is smaller than the outer diameter of the central grouting pipe. The central grouting pipe is provided with positioning rings on both sides of the flexible bladder to restrict its displacement.

5. The grouting reinforcement device for the working face according to claim 1, characterized in that, The controllable valve assembly includes a connecting pipe that connects the flexible bladder and the central grouting pipe, as well as a flow sensor and a solenoid valve connected to the controller.

6. The grouting reinforcement device for the working face according to claim 5, characterized in that, The flexible bladder has a rigid inner liner connected to its inlet inner wall and locked in place by a locking clamp. The rigid inner liner is snapped into the connecting tube, and a sealing ring is provided at the mating surface between the rigid inner liner and the connecting tube.

7. The grouting reinforcement device for the working face according to claim 1, characterized in that, The sealing cap is fixedly or detachably connected to the bottom of the central grouting pipe.

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