Three-blocking and two-injecting type expansion spiral bag hole packer

Abstract

A three-blocking two-injection type expansion spiral bag hole packer comprises expansion type bags, a gas extraction pipe and a grouting pipe, a primary grouting pipe is provided with grout outlets in the positions of the two expansion type bags respectively, and inlets of the primary grouting pipe and an inlet of a secondary grouting pipe are provided with quick connectors of a pressure pump respectively, and the quick connectors are connected with each other. A spiral bag communicated with the primary grouting pipe and the secondary grouting pipe is arranged on the pipeline between the two expansion bags, and an explosion valve communicated with the primary grouting pipe is arranged in the middle of the spiral bag. A primary grouting pipe is used for conducting grouting expansion on the bags at the two ends to block the drill hole, the pressure in the pipe is increased, an explosion valve is opened, and secondary sealing is conducted on grouting expansion of the spiral bags; in the grouting process of the secondary grouting pipe, the secondary grouting pipe is pulled out of the drill hole in the axial direction of the drill hole at a constant speed, so that grout is injected into a gap between the spiral bag and the hole wall at a constant speed through the groove of the secondary grouting pipe, the grout is evenly distributed and can be tightly attached to the hole walls with different hole diameters and irregular hole walls, and therefore the hole sealing performance and the pressure resistance can be effectively improved.

Description

Technical Field

[0001] This utility model relates to the field of coal mine gas extraction technology, and in particular to a three-plug two-injection expansion spiral bag sealer suitable for coal mine gas extraction. Background Technology

[0002] During coal mining, coal seams often generate coalbed methane (gas) due to their occurrence conditions. Gas is both an energy resource and a major cause of coal mine disasters. To control gas concentration and ensure safe production, efficient and stable gas sealing is necessary. Methods have evolved from polyurethane sealing and single-plug cement mortar sealing to the current "two-plug-one-injection" sealing device. While this method is currently popular, some problems remain, such as poor adaptability to drilling conditions, incomplete sealing due to uneven pressure or irregular borehole diameter, and uncertain injection pressure, leading to poor gas control results. Utility Model Content

[0003] The purpose of this invention is to overcome the shortcomings of the existing technology and provide a three-plug two-injection expansion spiral bag sealer that is highly adaptable, quick to install, and effective in use.

[0004] To achieve the above objectives, this utility model provides a three-plug, two-injection expansion spiral bag sealing device, comprising two expansion bags positioned at the front and rear of the borehole, a gas extraction pipe that enters the borehole and passes through the two expansion bags, a primary grouting pipe, and a secondary grouting pipe. The gas extraction pipe has a primary grouting pipe groove on each side and a secondary grouting pipe groove on each side. The primary grouting pipe has a grout outlet at each of the two expansion bags. The inlets of the primary and secondary grouting pipes are each equipped with a quick-connect interface for a pressure pump. The gas extraction pipe passing through the two expansion bags is connected to an air extraction pipe and a conical anti-blocking cap at the front of the air extraction pipe. A spiral bag communicating with the primary and secondary grouting pipes is located on the pipeline between the two expansion bags, and a rupture valve communicating with the primary grouting pipe is located in the middle of the spiral bag.

[0005] The expandable bag is fixed to the gas extraction pipe by a rolling strip, and its diameter after grouting and expansion is 1.1-1.2 times larger than the diameter of the hole.

[0006] Pressure relief valves are provided at the slurry outlets of the two inflatable bladders.

[0007] The length of the groove in the primary grouting pipe is from the end of the orifice to the middle section of the expansion bladder at the depth of the orifice.

[0008] The length of the groove in the secondary grouting pipe is from the end of the orifice to the front of the expansion bag at the depth of the hole before it passes through the bag.

[0009] The primary grouting pipe is a rigid grouting pipe, and its diameter matches the diameter of the primary grouting pipe groove.

[0010] The secondary grouting pipe is a flexible grouting pipe that can slide along the axial direction of the groove in the slot, and its diameter matches the diameter of the groove of the secondary grouting pipe.

[0011] The spiral bag is glued to the wall of the gas extraction pipe. The diameter of the spiral bag after grouting and expansion is 1.1-1.2 times larger than the borehole diameter.

[0012] Beneficial Effects: This utility model, based on the ordinary two-plug-one-injection sealing device, forms a three-plug-two-injection expansion spiral bag sealing device, which can form a three-stage high-efficiency seal and improve the sealing quality. It utilizes the expansion bags at both ends and the spiral bag in the middle to form a closed integral structure. The expansion bags at both ends expand uniformly under grouting pressure, effectively sealing the borehole wall and forming the first layer of gas sealing. After the expansion bags at both ends are filled, the middle spiral bag is ruptured by a burst valve to inject grout. The spiral bag provides additional strength and flexibility, allowing the sealing device to fit tightly in different borehole diameters and irregular borehole walls, forming the second layer of gas sealing. During the secondary grouting process, the secondary grouting pipe is pulled out of the borehole at a uniform speed along the borehole axis, allowing the grout to be injected uniformly into the gap between the spiral bag and the borehole wall through the groove of the secondary grouting pipe. The grout is evenly distributed, further improving the sealing performance and pressure resistance, forming the third layer of gas sealing. The triple-sealing structure provides efficient gas sealing in various pore sizes and with irregular walls. Its simple structure, ease of use, and excellent sealing effect make it widely applicable. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of the planar layout structure of this utility model.

[0014] Figure 2 A schematic diagram of the cross-section of the slotted section of the gas extraction pipe.

[0015] Figure 3 This is a schematic diagram of a spiral-shaped sac.

[0016] In the diagram: 1—Expansion bag; 2—Evacuation pipe; 3—Anti-clogging cap; 4—Primary grouting pipe; 5—Secondary grouting pipe; 6—Gas extraction pipe; 7—Spiral bag; 8—Roller; 9—Pressure relief valve; 10—Grouting outlet; 11—Burning valve; 12—Quick connector; 13—Pressure gauge; 14—Primary grouting pipe groove; 15—Secondary grouting pipe groove. Detailed Implementation

[0017] An embodiment of the present invention will be further described below with reference to the accompanying drawings:

[0018] This utility model discloses a three-plug, two-injection expansion spiral bag sealing device, mainly composed of two expansion bags 1 located at the front and rear positions within the borehole, a gas extraction pipe 6 that enters the borehole and passes through the two expansion bags, a primary grouting pipe 4, and a secondary grouting pipe 5. The expansion bags 1 are fixed to the gas extraction pipe 6 by a strip 8, and after grouting expansion, their diameter is 1.1-1.2 times larger than the borehole diameter. The gas extraction pipe 6 has a primary grouting pipe groove 14 for installing the primary grouting pipe 4 and a secondary grouting pipe groove 15 for installing the secondary grouting pipe 5 on both sides. The primary grouting pipe 4 has a grout outlet 10 at each of the two expansion bags. The length of the primary grouting pipe groove 14 extends from the borehole opening to the middle section of the expansion bag 1 at the depth of the borehole. The length of the secondary grouting pipe groove 15 extends from the borehole opening to the front part of the expansion bag 1 at the depth of the borehole before it passes through the bag. Pressure relief valves 9 are provided at the grout outlets 10 at the two expansion bag positions. The inlets of the primary grouting pipe 4 and the secondary grouting pipe 5 are respectively equipped with quick-connect interfaces 12 for connected pressure pumps 13. The gas extraction pipe 6, which passes through the two expansion bags, is connected at its front end to an extraction perforation pipe 2 and a conical anti-clogging cap 3 located at the front of the extraction perforation pipe 2. A spiral bag 7, communicating with the primary and secondary grouting pipes, is installed on the pipeline between the two expansion bags. The spiral bag 7 is glued to the wall of the gas extraction pipe, and its diameter after grouting expansion is 1.1-1.2 times larger than the borehole diameter. A rupture valve 11, communicating with the primary grouting pipe 4, is located in the middle of the spiral bag 7. The primary grouting pipe 4 is a rigid grouting pipe, with a diameter matching the diameter of the primary grouting pipe groove 14. The secondary grouting pipe 5 is a flexible grouting pipe that can slide along the groove axis in the slot, with a diameter matching the diameter of the secondary grouting pipe groove 15. The borehole is sealed by grouting expansion of the two end bags using a primary grouting pipe. The increased pressure inside the pipe opens the rupture valve to perform secondary sealing by grouting expansion of the spiral bag. During the secondary grouting process, the secondary grouting pipe is pulled out of the borehole at a uniform speed along the borehole axis, so that the grout is injected uniformly into the gap between the spiral bag and the borehole wall through the groove of the secondary grouting pipe. The grout is evenly distributed and can fit tightly in different borehole diameters and irregular borehole walls, thereby effectively improving the sealing performance and pressure resistance of the borehole.

[0019] Work process:

[0020] (1) Based on the drilling depth and borehole diameter, design the length and diameter of the gas extraction pipe 6, the diameter of the expansion bag 1 before and after grouting, and the length and diameter of the spiral bag 7.

[0021] (2) Insert the primary grouting pipe 4 into the primary grouting pipe groove 14 until one end penetrates into the distal expansion bag 1; insert the secondary grouting pipe 5 into the secondary grouting pipe groove 15 until one end penetrates into the front of the distal expansion bag 1.

[0022] (2) The spiral bag 7 is spirally wound and glued to the wall of the gas extraction pipe 6. The spiral bag 7 has an opening in the middle that is connected to the blast valve 11 on the primary grouting pipe.

[0023] (3) Insert the assembled three-plug two-injection expansion spiral bag sealer into the borehole, with the quick-connect 12 of the primary grouting pipe 4 and the secondary grouting pipe 5 near the borehole opening exposed outside the borehole. Connect the pressure gauge 13 to the primary grouting pipe.

[0024] (4) After mixing the grouting material, connect the grouting pump outlet pipe to the primary grouting pipe 4 through the quick connector 12, and adjust the grouting pressure;

[0025] (5) After the grouting material is passed through the grout outlet 10 and the drain valve 9, the expansion bags 1 at both ends are filled. The pressure in the primary grouting pipe 4 gradually increases. The burst valve 11 bursts and injects the grout into the spiral bag 7. After the spiral bag 7 is filled, the grouting is stopped when the pressure gauge 13 pressure rises steadily to above 1.8MPa.

[0026] (6) Disconnect the grout outlet pipe from the quick-connect interface 12 on the primary grouting pipe 4, and connect the grout outlet pipe to the quick-connect interface 12 on the secondary grouting pipe 5; connect the pressure gauge to the secondary grouting pipe;

[0027] (7) Turn on the grouting pump, inject the grout into the secondary grouting pipe 5, slowly and evenly pull out the secondary grouting pipe 5, keep the pressure gauge 13 reading stable, and stop grouting when the length of the pulled-out secondary grouting pipe 5 is equal to the length of the middle spiral section.

[0028] (8) Connect the gas extraction pipe 6 to the air pump to extract the coal seam gas;

[0029] (9) The air pump is turned off and the construction is completed.

Claims

1. A three-plug, two-injection expansion spiral bag sealing device, comprising two expansion bags (1) positioned at the front and rear of the borehole, a gas extraction pipe (6) entering the borehole and passing through the two expansion bags, a primary grouting pipe (4), and a secondary grouting pipe (5), characterized in that: The gas extraction pipe (6) is provided with a primary grouting pipe groove (14) for installing a primary grouting pipe (4) and a secondary grouting pipe groove (15) for installing a secondary grouting pipe (5) on both sides. The primary grouting pipe (4) is provided with a grout outlet (10) at the position of the two expansion bags. The inlet of the primary grouting pipe (4) and the secondary grouting pipe (5) is provided with a quick-connect interface (12) of a pressure pump (13) connected to it. The front of the gas extraction pipe (6) passing through the two expansion bags is connected with an air extraction pipe (2) and a conical anti-blocking cap (3) at the front of the air extraction pipe (2). A spiral bag (7) communicating with the primary and secondary grouting pipes is provided on the pipeline between the two expansion bags. A burst valve (11) communicating with the primary grouting pipe (4) is provided in the middle of the spiral bag (7).

2. The three-plug, two-injection expansion spiral bag sealing device according to claim 1, characterized in that: The inflatable bladder (1) is fixed to the gas extraction pipe (6) by a rolling strip (8), and its diameter after grouting and expansion is 1.1-1.2 times larger than the diameter of the hole.

3. The three-plug, two-injection expansion spiral bag sealing device according to claim 1, characterized in that: Pressure relief valves (9) are provided at the slurry outlets (10) of the two inflatable bladders.

4. The three-plug, two-injection expansion spiral bag sealing device according to claim 1, characterized in that: The length of the groove (14) of the primary grouting pipe is from the end of the orifice to the middle section of the expansion bladder (1) at the depth of the hole.

5. The three-plug, two-injection expansion spiral bag sealing device according to claim 1, characterized in that: The length of the groove (15) of the secondary grouting pipe is from the end of the hole to the front of the expansion bag (1) at the depth of the hole before it passes through the bag.

6. The three-plug, two-injection expansion spiral bag sealing device according to claim 1, characterized in that: The primary grouting pipe (4) is a rigid grouting pipe, and its diameter matches the diameter of the primary grouting pipe groove (14).

7. The three-plug, two-injection expansion spiral bag sealing device according to claim 1, characterized in that: The secondary grouting pipe (5) is a flexible grouting pipe that can slide along the groove axis in the slot, and its diameter matches the diameter of the secondary grouting pipe groove (15).

8. The three-plug, two-injection expansion spiral bag sealing device according to claim 1, characterized in that: The spiral bag (7) is glued to the wall of the gas extraction pipe. The diameter of the spiral bag (7) after grouting and expansion is 1.1-1.2 times larger than the borehole diameter.

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