Plugging device for coal seam drill hole during measurement of underground ultrasonic waves

Abstract

The utility model relates to the technical field of underground coal mine rock mass damage testing, in particular to a plugging device for a coal seam drill hole during underground ultrasonic wave measurement, which comprises a cylindrical supporting device and a trumpet-shaped expansion device, and a water pipe through hole and a testing through hole are arranged along the axial direction of the supporting device; the expansion device comprises an inner-layer expansion inner wall and an outer-layer expansion outer wall, and the small-caliber ends of the expansion inner wall and the expansion outer wall are fixedly connected with one end of the supporting device; the large-caliber ends of the expansion inner wall and the expansion outer wall are connected to form a container; an expansion through hole expansion device inner cavity is formed in the supporting device. The hole sealing device can solve the problem that a hole sealing device in the prior art is insufficient in sealing effect, the sealing efficiency can be improved, and water leakage is reduced; the device can be repeatedly used, so that waste is reduced; the device is low in manufacturing cost, simple to operate and wide in application range.

Description

Technical Field

[0001] The utility model relates to the technical field of underground rock mass damage testing in coal mines, in particular to a plugging device for coal seam drilling when measuring underground ultrasonic waves. Background Art

[0002] Rock mass ultrasonic testing is a new technology developed in recent decades. It mainly obtains the physical and mechanical properties, structural characteristics and stress state of the rock mass indirectly by detecting the changes in the acoustic parameters of ultrasound in the rock mass (such as ultrasonic wave velocity, attenuation coefficient, waveform, frequency, spectrum, amplitude, etc.). When conducting ultrasonic testing, water needs to be injected into the borehole to ensure the normal test through the coupling effect. Therefore, the sealing effect of the sealing device is crucial to ensure the accuracy of the ultrasonic test results. In order to save costs and reduce construction period, test drilling can generally be carried out using non-professional test boreholes (such as water exploration and drainage boreholes, pressure relief boreholes) that have been constructed underground in coal mines. However, the inclination direction of this non-professional test borehole is fixed, and most of them are arranged horizontally or tilted. Water is easy to overflow under the action of gravity, which puts forward more stringent requirements on the sealing of the sealing device. Utility Model Content

[0003] In order to solve the problem of insufficient sealing effect of the sealing device in the prior art, the utility model proposes a sealing device for coal seam drilling when measuring downhole ultrasonic waves, including a supporting device and an expansion device, the supporting device is cylindrical, and a water pipe through hole and a test through hole are arranged along the axial direction of the supporting device; the expansion device is in the shape of a trumpet as a whole, including an inner expansion inner wall and an outer expansion outer wall, the outer diameter of the small-diameter end of the expansion outer wall is the same as the outer diameter of the supporting device, the outer diameter of the small-diameter end of the expansion inner wall is slightly smaller than the outer diameter of the supporting device, and the small-diameter ends of the expansion inner wall and the expansion outer wall are both fixedly connected to one end of the supporting device; the large-diameter ends of the expansion inner wall and the expansion outer wall are connected to form a container; an expansion through hole is also arranged in the supporting device, and the expansion through hole connects the inner cavity enclosed by the expansion outer wall and the expansion inner wall.

[0004] Preferably, the diameter of the support device is consistent with or slightly larger than the diameter of the ultrasonic test borehole in the coal mine.

[0005] Preferably, the supporting device is made of a hard plastic material into a hard structure, or is made of rubber with a certain elasticity into a rubber plug form.

[0006] Preferably, the water pipe through hole is located at one end of the expansion device and is connected to the water injection guide pipe, and the test through hole at this end is connected to the measuring line guide pipe.

[0007] Preferably, the water injection guide tube and the measuring line guide tube are made of rubber with a certain elasticity.

[0008] Preferably, the elasticity of the expansion inner wall of the expansion device is smaller than that of the expansion outer wall.

[0009] Preferably, an expansion injection pipe is connected to one end of the expansion through hole away from the expansion device.

[0010] The utility model provides a plugging device for coal seam drilling when measuring underground ultrasonic waves, which has the following beneficial effects:

[0011] 1. The support device of the utility model can provide support for the expansion device, and after water is filled into the borehole, the expansion inner wall has a certain strength to support the inner wall of the borehole to form a seal, and the expansion outer wall has a limiting effect on the movement of the expansion inner wall after expansion, further improving the seal; the water injection guide pipe and the measuring line guide pipe have a certain elasticity to prevent water from leaking from the inner wall of the guide pipe and the hard water pipe and cable while extending the density length.

[0012] 2. The utility model can improve the sealing efficiency and reduce water leakage; the utility model can be reused to reduce waste; the utility model is cheap, easy to operate and has a wide range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a front view of the sealing device of the utility model;

[0014] Figure 2 This is a top view of the sealing device of the utility model;

[0015] Figure 3 This utility model Figure 2 AA section view;

[0016] Figure 4 This utility model Figure 2 BB cross-section diagram;

[0017] Figure 5 This is a three-dimensional oblique top view of the sealing device of the utility model;

[0018] Figure 6 This is a three-dimensional oblique upward view of the sealing device of the utility model;

[0019] In the figure, the corresponding relationship between the component names and the figure numbers is as follows:

[0020] 10-water pipe through hole; 11-water injection guide pipe; 20-expansion through hole; 21-expansion injection pipe; 30-test through hole; 31-measurement line guide pipe; 40-expansion device; 41-expansion outer wall; 42-expansion inner wall; 50-support device. DETAILED DESCRIPTION

[0021] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0022] like Figure 1-6 As shown, the utility model is a plugging device for coal seam drilling when measuring underground ultrasonic waves, comprising a support device 50 and an expansion device 40, wherein the support device 50 is cylindrical, and its diameter is consistent with or slightly larger than the aperture of the ultrasonic test drilling hole in the coal mine, and the support device 50 is made of a hard plastic material to form a hard structure, or is made of rubber with a certain elasticity to form a rubber plug; parallel to the axial direction of the support device 50, a water pipe through hole 10 and a test through hole 30 are symmetrically arranged relative to the axial center, one end of the water pipe through hole 10 is connected to a water injection guide pipe 11, and at this end, the test through hole 30 is connected to a measuring line guide pipe 31; the water injection guide pipe 11 and the measuring line guide pipe 31 are made of rubber with a certain elasticity;

[0023] The expansion device 40 is in a trumpet shape as a whole, including an inner expansion inner wall 42 and an outer expansion outer wall 41. The outer diameter of the small-diameter end of the expansion outer wall 41 is the same as the outer diameter of the support device 50, and the outer diameter of the small-diameter end of the expansion inner wall 42 is slightly smaller than the outer diameter of the support device 50. The small-diameter ends of the expansion inner wall 42 and the expansion outer wall 41 are fixedly connected to one end of the support device 50 where the water injection guide pipe 11 and the measuring line guide pipe 31 are set, and the water injection guide pipe 11 and the measuring line guide pipe 31 are located on the inner side of the expansion inner wall 42; the expansion inner wall 42 and the expansion outer wall 41 form a container that can hold gas or liquid, that is, the expansion inner wall 42 It is connected to the large-diameter end of the expansion outer wall 41; the expansion inner wall 42 of the expansion device 40 is made of rubber with a certain elasticity, so that it has a certain elasticity and a certain strength. The expansion outer wall 41 is made of high elastic material, so that when water or gas is injected into the expansion device 40, the expansion outer wall 41 produces an expansion effect while the expansion inner wall 42 only produces a small expansion but does not affect the overall shape; an expansion through hole 20 is also provided in the support device 40, and the expansion through hole 20 is connected to the inner cavity enclosed by the expansion outer wall 41 and the expansion inner wall 42, and the end of the expansion through hole 20 away from the measuring line guide tube 31 is connected to the expansion injection pipe 21.

[0024] The working mechanism of the utility model is as follows: after the ultrasonic test device is prepared, the probe and the cable are passed through the test through hole 30 and the measuring line guide tube 31, and the sealing device is first left outside the ultrasonic test borehole in the coal mine, and the probe and the cable are delivered into the borehole at the same time. After the probe reaches the measuring point, the hard water pipe is passed through the water pipe through hole 10 and the water injection guide tube 11 of the sealing device. The squeezing expansion device 40 is then inserted into the borehole, with the support device 50 outside and the expansion device 40 inside, and the large-diameter end of the bell mouth of the expansion device 40 is close to the inside, and the air pump or water pump is connected to the expansion injection tube 21, and then gas or liquid is pumped into the expansion device 40 to expand the expansion outer wall 41 to squeeze the inner wall of the borehole to produce a sealing effect. Then water is injected into the borehole through a hard water pipe and tested by an ultrasonic testing device. For horizontal drilling or inclined drilling, water will generate a certain pressure on the expansion device 40 after it is filled into the borehole, but the expansion inner wall 42 has a certain strength to support the inner wall of the borehole to form a seal, and the expansion outer wall 41 further improves the seal after expansion. The water injection guide pipe 11 and the measuring line guide pipe 31 have a certain elasticity to prevent water from leaking from the inner wall of the guide pipe and the hard water pipe and cable, while extending the density length.

[0025] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A plugging device for coal seam drilling when measuring underground ultrasonic waves, comprising a supporting device and an expansion device, characterized in that: The support device is cylindrical, and a water pipe through hole and a test through hole are arranged along the axial direction of the support device; the expansion device is in the shape of a trumpet as a whole, including an inner expansion inner wall and an outer expansion outer wall, the outer diameter of the small-diameter end of the expansion outer wall is the same as the outer diameter of the support device, the outer diameter of the small-diameter end of the expansion inner wall is smaller than the outer diameter of the support device, and the small-diameter ends of the expansion inner wall and the expansion outer wall are both fixedly connected to one end of the support device; the large-diameter ends of the expansion inner wall and the expansion outer wall are connected to form a container; an expansion through hole is also arranged in the support device, and the expansion through hole connects the inner cavity enclosed by the expansion outer wall and the expansion inner wall.

2. The blocking device according to claim 1, characterized in that: The diameter of the support device is consistent with or larger than the diameter of the ultrasonic test borehole in the coal mine.

3. The blocking device according to claim 1 or 2, characterized in that: The supporting device is made of hard plastic material to form a hard structure, or is made of rubber with certain elasticity to form a rubber plug.

4. The blocking device according to claim 1, characterized in that: The water pipe through hole is located at one end of the expansion device and is connected to the water injection guide pipe, and the test through hole at this end is connected to the measuring line guide pipe.

5. The blocking device according to claim 4, characterized in that: The water injection guide pipe and the measuring line guide pipe are made of rubber with certain elasticity.

6. The blocking device according to claim 1, characterized in that: The elasticity of the expansion inner wall of the expansion device is smaller than that of the expansion outer wall.

7. The blocking device according to claim 1 or 6, characterized in that: An expansion injection pipe is connected to one end of the expansion through hole away from the expansion device.

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