An in-situ testing device for coal and rock strata permeability

Abstract

This utility model discloses an in-situ permeability testing device for coal and rock formations, comprising a first pressure-controlled setting device, a second pressure-controlled setting device, and an extension tube. Two sets of extension tubes are provided. A grouting pipe is fixedly connected between the first and second pressure-controlled setting devices. Two sets of grouting pipes are also provided. A pushing structure is fixedly installed on one side surface of the second pressure-controlled setting device. Each grouting pipe includes a first pipe body, a second pipe body, and a first threaded end. First threaded ends are fixedly installed on adjacent surfaces of the first and second pipe bodies. Two sets of first threaded ends are provided. The extension tube includes a sleeve, a third pipe body, a second threaded end, a sealing plug, an embedding groove, and an air bladder. Second threaded ends are fixedly installed on both sides of the third pipe body. This in-situ permeability testing device for coal and rock formations can quickly extend the grouting pipe, has strong sealing performance, and can clean impurities inside the borehole.

Description

Technical Field

[0001] This utility model relates to the field of coal and rock strata permeability testing, and in particular to an in-situ testing device for coal and rock strata permeability. Background Technology

[0002] Coal and rock strata permeability refers to the ability of coal and rock strata to allow fluids (such as gas and water) to pass through their pores and fractures. It is a key parameter for measuring the permeability of coal and rock strata and is of great significance to fields such as coal mine gas extraction, coalbed methane development, groundwater flow analysis, and coal and rock mechanics research. An existing application (CN201821605540.2) discloses an in-situ testing device for coal and rock strata permeability. This device comprises a grouting pipe I, a grouting pipe II, and a pressure-controlled setting device I and a pressure-controlled setting device II. This invention allows for in-situ testing of permeability at any location and determination of the regional coal and rock strata seepage field by adjusting the length of the grouting pipe. The device is reusable, and the testing process only requires determining the viscosity of the grouting fluid, the pressure-controlled setting device I, and the pressure-controlled setting device II. The data on the real-time decay of borehole length and slurry pressure I between the pressure-controlled setter II is simple and convenient to operate and the test results are reliable. However, in use, the sections of the multi-section grouting pipe are connected by bolts or plugs. The bolts have poor sealing performance and the plugs have insufficient stability. During the test, the pressure-controlled setter needs to be inserted into the borehole. Even after cleaning, there are still impurities such as sand and gravel in the borehole, which can easily cause wear to the pressure-controlled setter, thereby shortening the service life of the test device. Therefore, we propose an in-situ test device for coal and rock strata permeability. Utility Model Content

[0003] The main purpose of this invention is to provide an in-situ testing device for coal and rock strata permeability, which can effectively solve the problems in the background art.

[0004] To achieve the above objectives, the technical solution adopted by this utility model is as follows: An in-situ permeability testing device for coal and rock formations includes a first pressure-controlled setter, a second pressure-controlled setter, and an extension tube. The extension tube is in two sets. A grouting pipe is fixedly connected between the first and second pressure-controlled setters. The grouting pipe is in two sets. A pushing structure is fixedly installed on one side surface of the second pressure-controlled setter.

[0005] Furthermore, the grouting pipe includes a first pipe body, a second pipe body, and a first threaded end. The first threaded end is fixedly installed on the adjacent surfaces of the first pipe body and the second pipe body, and there are two sets of the first threaded end.

[0006] Furthermore, the extension tube includes a sleeve, a third tube body, a second threaded end, a sealing plug, an embedding groove, and an air bladder. The second threaded end is fixedly installed on both sides of the third tube body. There are two sets of the second threaded end and two sets of sleeves. An embedding groove is opened in the middle of the inner surface of each sleeve. An air bladder is embedded in the interior of each embedding groove. A sealing plug is embedded between the sleeve and the air bladder.

[0007] Furthermore, the second threaded ends are all located between the first threaded ends, the sleeve is sleeved and installed on the surface of the second threaded ends and the first threaded ends, and the second tube body is respectively embedded and installed on one side surface of the first pressure-controlled seat sealer.

[0008] Furthermore, the pushing structure includes a cleaning brush, a cross bar, and a connecting rod. The cross bar is fixedly installed on one side surface of the connecting rod, and the cleaning brush is sleeved on the surface of the cross bar.

[0009] Furthermore, the cleaning brush is fixedly installed on one side surface of the second pressure-controlled seat sealer.

[0010] In summary, due to the adoption of the above technical solution, the beneficial effects of this application are: In this utility model, the extension tube can be spliced ​​between the first tube body and the second tube body as needed, thereby extending the grouting pipe. It is easy to operate and has strong sealing performance. The push structure is designed to clean the borehole when the test device enters the borehole, which helps prevent impurities such as sand and gravel from remaining in the borehole and causing wear on the surface of the pressure-controlled setter, thereby extending the service life of the device. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the overall structure of an in-situ testing device for coal and rock strata permeability according to the present invention. Figure 2 This is a detailed drawing of the extension tube of an in-situ testing device for coal and rock strata permeability according to this utility model; Figure 3 This is a cross-sectional view of the casing of an in-situ permeability testing device for coal and rock formations according to this utility model; Figure 4 This is a detailed diagram of the driving structure of an in-situ testing device for coal and rock strata permeability according to this utility model.

[0012] In the diagram: 1. Grouting pipe; 101. First pipe body; 102. Second pipe body; 103. First threaded end; 2. Extension pipe; 201. Sleeve; 202. Third pipe body; 203. Second threaded end; 204. Sealing plug; 205. Insertion groove; 206. Airbag; 3. First pressure-controlled setting device; 4. Second pressure-controlled setting device; 5. Pushing structure; 501. Cleaning brush; 502. Cross bar; 503. Connecting rod. Detailed Implementation

[0013] 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 in conjunction with the embodiments of this application. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0014] Reference Figure 1-4 A coal and rock strata permeability in-situ testing device includes a first pressure-controlled setter 3, a second pressure-controlled setter 4 and an extension pipe 2, the extension pipe 2 being two sets, a grouting pipe 1 being fixedly connected between the first pressure-controlled setter 3 and the second pressure-controlled setter 4, the grouting pipe 1 being two sets, and a pushing structure 5 being fixedly installed on one side surface of the second pressure-controlled setter 4. In a preferred embodiment, the grouting pipe 1 includes a first pipe body 101, a second pipe body 102, and a first threaded end 103. The first threaded end 103 is fixedly installed on the adjacent surfaces of the first pipe body 101 and the second pipe body 102. There are two sets of first threaded ends 103. The first pipe body 101 is provided with structures such as a shut-off valve, a check valve, a pressure gauge, and a pressure relief pipe.

[0015] In a preferred embodiment, the extension tube 2 includes a sleeve 201, a third tube body 202, a second threaded end 203, a sealing plug 204, an embedding groove 205, and an airbag 206. The second threaded end 203 is fixedly installed on both sides of the third tube body 202. There are two sets of second threaded ends 203. There are two sets of sleeves 201. The inner surface of the sleeve 201 is provided with an embedding groove 205 in the middle. An airbag 206 is embedded in the embedding groove 205. A sealing plug 204 is embedded between the sleeve 201 and the airbag 206.

[0016] In a preferred embodiment, the second threaded ends 203 are all located between the first threaded ends 103. The sleeve 201 is sleeved and installed on the surfaces of the second threaded ends 203 and the first threaded ends 103. The second tube body 102 is respectively embedded and installed on one side surface of the first pressure-controlled seat sealer 3. The inner surface of the sleeve 201 is provided with threads, so that the sleeve 201 is connected to the second threaded ends 203 and the first threaded ends 103 by threads. The sealing plug 204 can seal the airbag 206.

[0017] In a preferred embodiment, the pushing structure 5 includes a cleaning brush 501, a cross bar 502, and a connecting rod 503. The cross bar 502 is fixedly installed on one side surface of the connecting rod 503. The cleaning brush 501 is sleeved on the surface of the cross bar 502. The surface of the cleaning brush 501 is provided with bristles, which can push sand and other impurities forward when moving.

[0018] In a preferred embodiment, the cleaning brush 501 is fixedly mounted on one side surface of the second pressure-controlled seat sealer 4.

[0019] It should be noted that when the second pressure-controlled setting device 4 is embedded into the borehole, the pushing structure 5 enters the borehole first. As the second pressure-controlled setting device 4 gradually moves inward, the connecting rod 503 pushes the cross rod 502 to one side, thereby pushing the impurities to one side through the cleaning brush 501, so as to avoid impurities getting stuck on the surface of the borehole and the first pressure-controlled setting device 3 and the second pressure-controlled setting device 4, causing wear to the first pressure-controlled setting device 3 and the second pressure-controlled setting device 4. When the grouting pipe 1 needs to be extended, the third pipe body 202 is placed between the first pipe body 101 and the second pipe body 102, so that the sleeve 201 is fitted over the second threaded end 203 and the first threaded end 103 and tightened. With the help of an air pump, gas is filled into the air bladder 206, causing the air bladder 206 to expand, thereby sealing the connection between the second threaded end 203 and the first threaded end 103. Then, the sealing plug 204 is used to seal it.

[0020] The above embodiments are only used to illustrate the technical solutions of this application, and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application.

Claims

1. A coal bed permeability in-situ testing apparatus, characterized in that: It includes a first pressure-controlled setter (3), a second pressure-controlled setter (4) and an extension pipe (2). The extension pipe (2) consists of two sets. A grouting pipe (1) is fixedly connected between the first pressure-controlled setter (3) and the second pressure-controlled setter (4). The grouting pipe (1) consists of two sets. A pushing structure (5) is fixedly installed on one side surface of the second pressure-controlled setter (4).

2. The coal bed permeability in-situ testing device of claim 1, wherein: The grouting pipe (1) includes a first pipe body (101), a second pipe body (102), and a first threaded end (103). The first threaded end (103) is fixedly installed on the adjacent surfaces of the first pipe body (101) and the second pipe body (102). There are two sets of the first threaded end (103).

3. The coal bed permeability in-situ testing device of claim 2, wherein: The extension tube (2) includes a sleeve (201), a third tube body (202), a second threaded end (203), a sealing plug (204), an embedding groove (205), and an airbag (206). The second threaded end (203) is fixedly installed on both sides of the third tube body (202). There are two sets of the second threaded end (203) and two sets of the sleeve (201). An embedding groove (205) is opened in the middle of the inner surface of the sleeve (201). An airbag (206) is embedded in the interior of the embedding groove (205). A sealing plug (204) is embedded between the sleeve (201) and the airbag (206).

4. The coal bed permeability in-situ testing device of claim 3, wherein: The second threaded end (203) is located between the first threaded end (103). The sleeve (201) is sleeved and installed on the surface of the second threaded end (203) and the first threaded end (103). The second tube body (102) is respectively embedded and installed on one side surface of the first pressure-controlled seat sealer (3).

5. The coal bed permeability in-situ testing device of claim 4, wherein: The pushing structure (5) includes a cleaning brush (501), a cross bar (502), and a connecting rod (503). The cross bar (502) is fixedly installed on one side surface of the connecting rod (503), and the cleaning brush (501) is sleeved on the surface of the cross bar (502).

6. The coal bed permeability in-situ testing device of claim 5, wherein: The cleaning brush (501) is fixedly installed on one side surface of the second pressure-controlled seat sealer (4).

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