Coal mine large-aperture through hole well cementation water stop device and construction method

Abstract

The invention relates to the technical field of mining capital construction, and provides a coal mine large-aperture through hole well cementation water stop device which is arranged on a casing pipe and comprises a casing pipe clamp and a water stop plate arranged at the bottom of the casing pipe clamp, and the casing pipe clamp is arranged on the outer wall of the casing pipe in a sleeving mode; the water stop plate horizontally extends outwards from the bottom of the sleeve hoop and is used for abutting against the bottom wall of the through hole and covering an annular gap between the inner wall of the through hole and the outer wall of the sleeve. According to the coal mine large-aperture through hole well cementation underground water stopping device, the situation that a water stopping plate is damaged in the process of being placed underground is reduced. The invention further provides a construction method of the coal mine large-aperture through hole well cementation water stop device.

Description

Technical Field

[0001] This application relates to the field of mining infrastructure technology, and in particular to a coal mine large-diameter through-hole cementing and water-stopping device and construction method. Background Technology

[0002] In the mining infrastructure sector, the construction of large-diameter through-holes in coal mines is of paramount importance. These through-holes, such as gas extraction holes, grouting holes, or drainage holes, play a crucial role in the safe production and resource development of coal mines. In traditional construction of large-diameter through-holes in coal mines, to achieve water-stopping sealing of the hole wall, a pre-installed water-stop plate is typically lowered to the designed position simultaneously with the casing. Specifically, the metal water-stop plate is installed on the outer wall of the casing by welding or mechanical fixing, and then lowered into the bottom of the through-hole along with the casing as a whole. A permanent seal is then achieved through grouting and cementing.

[0003] Due to the complex environment within the borehole, its inner wall may contain protruding rock masses, residual drill bits, or deposited debris. Simultaneously, the casing is prone to swaying under the influence of gravity and drilling rig thrust. When the waterstop plate is rigidly connected to the casing and descends synchronously, the edge of the waterstop plate is highly susceptible to violent collisions with the inner wall of the borehole and the hard structure at the bottom of the borehole. Such collisions can range from minor deformation of the waterstop plate and damage to the sealing surface, affecting the water-stopping effect, to more serious damage that could lead to weld cracking or even structural disintegration, causing the entire water-stopping sealing system to fail and thus failing to ensure construction safety and project quality. Summary of the Invention To reduce the risk of damage to the waterstop plate during its placement underground, this application provides a waterstop device and construction method for solidifying large-diameter through holes in coal mines.

[0004] Firstly, the technical solution of the coal mine large-diameter through-hole cementing and water-stopping device provided in this application is as follows: A water-stopping device for cementing large-diameter through holes in coal mines is installed on the casing, including a casing clamp and a water-stopping plate installed at the bottom of the casing clamp. The casing clamp is sleeved on the outer wall of the casing. The water-stopping plate extends horizontally outward from the bottom of the casing clamp and is used to abut against the bottom wall of the through hole and cover the annular gap between the inner wall of the through hole and the outer wall of the casing.

[0005] By adopting the above technical solution, after the sleeve is installed in the through hole, the sleeve clamp is fitted on the outer wall of the sleeve and the waterstop plate abuts against the inner wall of the through hole. The sleeve clamp is a modular type, which can be assembled after the sleeve is installed in the through hole, thus avoiding the situation where the waterstop plate enters the bottom of the through hole along with the sleeve, causing damage to the waterstop plate.

[0006] Optionally, the sleeve clamp consists of two opposing half clamps, each half clamp having connecting plates extending from both sides, and the connecting plates of the two half clamps are connected by bolts; the waterstop plate is semi-circular and is fixed to the outer edge of the bottom of the half clamp.

[0007] By adopting the above technical solution, the welding method is avoided in connecting the waterstop plate and the sleeve. Instead, two half clamps are bolted together to hold the outer wall of the sleeve. This allows the sleeve clamps to be assembled with the sleeve after the sleeve is inserted into the through hole, thus improving convenience.

[0008] Optionally, the sleeve clamp has a gap with the outer wall of the sleeve to form an injection cavity, and the sleeve clamp is equipped with a detachable injection tube for filling the injection slurry with sealant.

[0009] By adopting the above technical solution, a gap is left between the casing clamp and the outer wall of the casing, so that the casing clamp can be slid from the top of the casing to the bottom of the casing and abut against the bottom of the well, avoiding the need for workers to go deep into the bottom of the through hole; and by setting a detachable injection pipe, it is possible to inject sealant into the grouting cavity to improve the sealing performance of the waterstop plate.

[0010] Optionally, the sleeve clamp has a gap with the outer wall of the sleeve to form an injection cavity, and the sleeve clamp is equipped with a detachable injection tube for filling the injection slurry with sealant.

[0011] By adopting the above technical solution, the friction between the casing clamp and the casing can be reduced, thereby improving the smoothness of the casing clamp sliding from the top of the casing to the bottom of the casing.

[0012] Optionally, the inner wall of the sleeve clamp is provided with an expansion groove, and an airbag is installed in the expansion groove; the sleeve clamp is provided with a main injection channel and an injection branch channel connected to the main injection channel; the main injection channel is also provided with a venting groove for connecting to the airbag; a sealing component is installed in the injection branch channel, and a sliding block is slidably installed in the main injection channel. When the sliding block is inserted into the venting groove, the sealing component opens the injection branch channel.

[0013] By adopting the above technical solution, when injecting sealant into the injection cavity, the sealant is injected into the main injection channel through the injection tube. At this time, the pressure in the channel increases and pushes the sliding block, causing the airbag to expand and press against the outer wall of the sleeve. This allows the sealant to be poured from bottom to top during the injection process, so that the sealant can fill the entire injection cavity and improve the sealing effect. It also reduces the situation where the sealant enters the water injection plate and the bottom of the through hole through the injection cavity, thus reducing the waste of sealant.

[0014] Optionally, the sealing assembly includes a sealing block and a spring. The inner wall of the glue injection channel has a movable groove, and the sealing block is movably installed in the movable groove. The spring force is used to drive the sealing block to abut against the inner wall of the glue injection channel on the side away from the movable groove. The movable groove has an unlocking groove that communicates with the venting groove. The outer wall of the sealing block is provided with an unlocking plate, and one end of the unlocking plate passes through the unlocking groove and enters the venting groove.

[0015] By adopting the above technical solution, during the movement of the sliding block toward the venting groove, the airbag can be inflated and come into contact with the outer wall of the sleeve; and it can be inserted into the venting groove. During the process of entering the venting groove, the sliding block can come into contact with the unlocking plate and drive the unlocking plate to slide in the unlocking groove, so that the sealing block cancels the contact with the inner wall of the glue injection channel, thereby opening the glue injection channel so as to facilitate the injection of sealant into the glue injection cavity.

[0016] Optionally, the sleeve clamp is provided with a plug pipe for communicating with the main glue injection channel, and the glue injection tube is sleeved on the outer wall of the plug pipe; the plug pipe is connected to the glue injection tube through an electromagnetic component.

[0017] By adopting the above technical solution, the electromagnetic component can connect the injection tube to the insertion tube to facilitate the injection of sealant into the injection cavity; and after the injection cavity is filled with sealant, the connection between the injection tube and the insertion tube can be disconnected by using the electromagnetic component. By applying a pulling force to the injection tube, the injection tube can be easily disconnected from the insertion tube, thereby allowing the injection tube to be pulled out of the through hole.

[0018] Secondly, the coal mine large-diameter through-hole cementing and water-stopping device provided in this application specifically includes the following steps: S1, insert the casing into the large-diameter through hole; S2, fix the water-stopping device to the bottom of the casing so that the water-stopping plate fits against the bottom of the tunnel; S3, small particles of sand and gravel are placed on the ground into the annular gap formed between the inner wall of the through hole and the outer wall of the casing to fill the gap; S4, grouting is performed in three stages in the annular gap by inserting a tube for grouting. After each grouting is completed and solidified for 72 hours, the next grouting is performed. S5, cementing completed, check the sealing and water-stopping effect.

[0019] By adopting the above technical solution, a casing is first installed in a large-diameter through hole, which provides a foundation for the subsequent installation of the water-stopping device. The water-stopping device is fixed at the bottom of the casing and the water-stopping plate is made to fit against the bottom of the tunnel to prevent the water-stopping plate from being damaged when it enters the bottom of the through hole along with the casing. Small-particle sand and gravel are placed on the ground to fill the annular gap between the inner wall of the through hole and the outer wall of the casing, which can enhance the water-stopping effect. Grouting is performed in three stages, with each stage solidifying for 72 hours before the next grouting is performed, so that the annular gap is filled more densely and the water-stopping sealing performance is improved. Finally, the sealing effect is checked to ensure that the quality of the entire water-stopping project meets the standards.

[0020] Optionally, in step S2, after the casing is installed, a well support is provided on the ground for connection with the top of the casing.

[0021] By adopting the above technical solution, after the casing is installed, a well support connected to the top of the casing is set on the ground, which can stabilize the casing and ensure the smooth progress of subsequent construction steps such as small-particle sand and gravel injection and grouting.

[0022] In summary, this application includes at least one of the following beneficial technical effects: 1. By setting sleeve clamps, the sleeve can be assembled after it is installed in the through hole, avoiding the situation where the waterstop plate enters the bottom of the through hole along with the sleeve, which would cause damage to the waterstop plate. 2. By leaving a gap between the casing clamp and the outer wall of the casing, the casing clamp can be slid from the top of the casing to the bottom of the casing and abut against the bottom of the well, avoiding the need for workers to go deep into the bottom of the through hole; and by setting a detachable injection pipe, it is possible to inject sealant into the grouting cavity to improve the sealing performance of the waterstop. Attached Figure Description

[0023] Figure 1 This is a structural schematic diagram of Example 1; Figure 2 This is a schematic diagram of the installation of the sleeve and through hole in Example 1; Figure 3 This is a partial cross-sectional view of Embodiment 2; Figure 4 yes Figure 3 A magnified view of a portion at point a; Figure 5 This is a schematic diagram of the semi-clamp structure in Example 2.

[0024] Explanation of reference numerals in the attached drawings: 1. Sleeve clamp; 11. Half clamp; 12. Bolt hole; 13. Connecting plate; 14. Injection cavity; 15. Ball bearing; 16. Main injection channel; 17. Sub-injection channel; 171. Annular channel; 172. Connecting groove; 18. Injection hole; 2. Waterstop plate; 3. Sleeve; 31. Annular gap; 32. First grouting pipe; 33. Second grouting pipe; 34. Third grouting pipe; 4. Airbag; 41. Expansion groove; 42. Ventilation groove; 5. Injection pipe; 51. Insertion pipe; 6. Sliding block; 7. Sealing assembly; 71. Sealing block; 72. Spring; 73. Unlocking plate; 74. Movable groove; 75. Unlocking groove. Detailed Implementation

[0025] The following is in conjunction with the appendix Figure 1-5 This application will be described in further detail.

[0026] Example 1: This application discloses a cementing and water-stopping device for large-diameter through holes in coal mines.

[0027] Reference Figure 1 A cementing and water-stopping device for large-diameter through holes in coal mines includes a casing clamp 1 and a water-stopping plate 2. The casing clamp 1 is fitted onto the outer wall of the casing 3, and the water-stopping plate 2 is located at the bottom of the casing clamp 1. The casing clamp 1 includes two opposing half-clamps 11. The half-clamps 11 are usually made of metal and have a certain strength and toughness, which can firmly hold the casing 3. Each half-clamp 11 has connecting plates 13 extending from both sides. The connecting plates 13 are generally integrally formed with the half-clamps 11, and their shape is flat, and their material is the same as that of the half-clamps 11.

[0028] Each of the connecting plates 13 of the two semi-clamps 11 has multiple bolt holes 12. The connecting plates 13 of adjacent semi-clamps 11 are connected by bolts, typically high-strength carbon steel bolts, which provide sufficient connecting force. This connection method allows the two semi-clamps 11 to tightly grip the outer wall of the sleeve, avoiding the need for welding to connect the waterstop plate 2 to the sleeve 3, making installation and disassembly more convenient. In practical applications, other connection methods such as snap-fit ​​connections can also be used instead of bolt connections, as long as a reliable connection between the two semi-clamps 11 is achieved.

[0029] Two sets of waterstop plates 2 are provided, each set being a semi-circular ring. These waterstop plates 2 can be made of carbon steel, low-alloy steel, or stainless steel. The waterstop plates 2 are welded to the outer edge of the bottom of the semi-clamp 11. Once the waterstop device is installed, the extension abuts against the bottom wall of the through hole, effectively covering the annular gap 31 between the inner wall of the through hole and the outer wall of the sleeve 3, thus providing a good waterstop effect.

[0030] The implementation principle of Embodiment 1 of this application is as follows: The sleeve clamp 1 is an assembly type, which can be assembled after the sleeve 3 is installed in the through hole, thus avoiding the situation where the waterstop 2 enters the bottom of the through hole along with the sleeve 3, which would cause damage to the waterstop 2.

[0031] Reference Figure 2 This embodiment also discloses a construction method for a cementing and water-stopping device for large-diameter through holes in coal mines, specifically including the following steps: S1, the casing 3 is lowered into the large-diameter through hole of the coal mine using a lifting device, and the position of the casing 3 in the through hole is confirmed.

[0032] S2, install a well support at the ground through hole position to reduce the self-weight pressure of the casing 3 in the through hole; first use a lifting clamp to lower the two half clamps 11 to the bottom of the through hole; then use bolts to pass through the bolt holes 12 to hold the two half clamps 11 against the outer wall of the casing 3, so that the waterstop 2 abuts against the bottom wall of the through hole and covers the annular gap 31.

[0033] S3, one ton of small-particle sand and gravel is placed on the ground into the annular gap 31 to fill the gap.

[0034] S4, grouting is performed in three stages in the annular gap by inserting a tube for grouting. After each grouting is completed and solidified for 72 hours, the next grouting is performed. S41, lower the first grouting pipe 32 along the annular gap 31 to start the first insertion grouting. Inject two tons of cement grout through the first grouting pipe 32. After the grouting is completed, immediately close the valve of the first grouting pipe 32 and let it solidify for 72 hours to form an annular cement plug. S42, lower the second grouting pipe 33 along the annular gap and start the second insertion-type grouting. Inject cement slurry into the well through the second grouting pipe 33. After the grouting is completed, immediately close the valve of the second grouting pipe 33 and let it solidify for 72 hours to form an annular cement plug. S43, lower the third grouting pipe 34 along the annular gap to start the third insertion-type grouting. Inject cement slurry through the third grouting pipe 34 to the wellhead position. After the grouting is completed, immediately close the valve of the third grouting pipe 34 and let it solidify for 72 hours to form an annular cement plug.

[0035] S5, cementing completed, check the sealing and water-stopping effect.

[0036] Example 2: This application discloses a cementing and water-stopping device for large-diameter through holes in coal mines.

[0037] Reference Figure 3The difference between Embodiment 2 and Embodiment 1 is that: a gap exists between the sleeve clamp 1 and the outer wall of the sleeve 3, forming a glue injection cavity 14. A ball bearing 15 is rotatably mounted on the inner wall of the half-clamp 11. The ball bearing 15 is typically made of wear-resistant materials such as stainless steel and is spherical. The function of the ball bearing 15 is to abut against the outer wall of the sleeve 3. When the sleeve clamp 1 slides on the outer wall of the sleeve 3, the ball bearing 15 reduces the friction between them, making the installation of the sleeve clamp 1 smoother. In practical applications, other rolling components such as rollers can also be used to replace the ball bearing 15, as long as the effect of reducing friction is achieved.

[0038] The semi-clamp 11 is equipped with a detachable injection tube 5, which is used to fill the injection cavity 14 with sealant. The upper surface of the semi-clamp 11 is provided with a plug tube 51, which is made of metal and whose outer diameter is adapted to the inner diameter of the injection tube 5. The injection tube 5 is sleeved on the outer wall of the plug tube 51, and the plug tube 51 is connected to the injection tube 5 through an electromagnetic component. The electromagnetic component includes an electromagnetic component installed on the injection tube 5 and a permanent magnet installed on the plug tube 51. The electromagnetic component can realize the magnetic connection between the injection tube and the plug tube 51 by energizing / de-energizing. The electromagnetic component is existing technology and will not be described in detail here.

[0039] Simultaneously refer to Figure 4 and Figure 5 The semi-clamp 11 is provided with a main injection channel 16 and an injection branch channel 17 connected to the main injection channel 16. The insertion pipe 51 is connected to the injection channel. The main injection channel 16 and the injection branch channel 17 are generally channels opened inside the sleeve clamp 1 for conveying sealant. The injection branch channel 17 includes an annular channel 171 and a connecting groove 172. The connecting groove 172 is used to connect the main injection channel 16 and the annular channel 171. The inner wall of the semi-clamp 11 is provided with a plurality of injection holes 18 connected to the annular channel 171. All injection holes 18 are spaced along the inner peripheral wall of the semi-clamp 11 so as to uniformly inject sealant into the injection cavity 14.

[0040] Reference Figure 5 The inner wall of the semi-clamp 11 is provided with an expansion groove 41, and the two ends of the expansion groove 41 are respectively connected to the two sides of the semi-clamp 11. An airbag 4 is installed in the expansion groove 41, and the airbag 4 is used to expand and abut against the outer wall of the sleeve 3. The semi-clamp 11 is provided with a venting groove 42, which is used to connect the airbag 4 and the glue injection main channel 16, and the extension direction of the venting groove 42 is set in the same direction as the extension direction of the glue injection main channel 16.

[0041] Reference Figure 4The injection channel 17 is equipped with a sealing component 7, which is used to cover the end of the connecting groove 172. A sliding block 6 is slidably installed in the main injection channel 16. When sealant is injected into the main injection channel 16, the pressure in the channel increases, pushing the sliding block 6. When the sliding block 6 is inserted into the venting groove 42, the sealing component 7 opens the injection channel 17, allowing the sealant to flow out from the injection channel 17, realizing a bottom-up pouring method, so as to fill the injection cavity 14 with sealant and improve the sealing effect.

[0042] In this embodiment, the sliding block 6 is connected to the outer wall of the semi-clamp 11 by a pull rope (not shown in the figure). When the sleeve clamp 1 enters the bottom of the through hole, it can prevent the sliding block 6 from sliding freely in the glue injection main channel 16. When sealant is injected into the glue injection main channel 16, the pressure in the channel increases, which can cause the pull rope to break, so that the sliding block 6 slides in the glue injection main channel 16.

[0043] The sealing assembly 7 includes a sealing block 71 and a spring 72. The sealing block 71 is made of metal or plastic. The inner wall of the annular channel 171 has a movable groove 74, and the sealing block 71 is movably installed in the movable groove 74. It can move to a certain extent in the movable groove 74 and can seal the annular channel 171.

[0044] Spring 72 is generally a helical spring 72, made of materials such as carbon steel, and is installed between the inner wall of the movable groove 74 and the sealing block 71; its elasticity is used to drive the sealing block 71 to abut against the inner wall of the glue injection support channel on the side away from the movable groove 74, thereby sealing the glue injection support channel 17.

[0045] In this embodiment, the outer wall of the sealing block 71 is wrapped with a rubber layer, which can increase the sealing connection groove 172 of the sealing block 71 so that the sliding block 6 can be inserted into the venting groove 42 under pressure difference during the process of injecting sealant into the injection tube 5.

[0046] The movable groove 74 has an unlocking groove 75 that communicates with the venting groove 42. The unlocking groove 75 is a channel structure. The outer wall of the sealing block 71 is provided with an unlocking plate 73, which is a flat plate structure. One end of the unlocking plate 73 passes through the unlocking groove 75 and enters the venting groove 42. When the sliding block 6 is inserted into the venting groove 42, it will push the unlocking plate 73, thereby causing the sealing block 71 to overcome the elastic force of the spring 72 and open the glue injection support channel 17.

[0047] The implementation principle of Embodiment 2 of this application is as follows: By leaving a gap between the sleeve clamp 1 and the outer wall of the sleeve 3, the sleeve clamp 1 can be slid from the top of the sleeve 3 to the bottom of the sleeve 3. Then, the sleeve clamp 1 is hoisted by hoisting equipment and transported to the bottom of the through hole, so that the waterstop 2 abuts against the bottom of the through hole. Then, sealant is injected into the sealant injection cavity 14 through the sealant injection pipe 5, thereby achieving the sealing effect of the waterstop 2. This method can avoid workers from reaching into the bottom of the through hole and improve the safety of construction.

[0048] The above are preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made to the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A water-stopping device for cementing large-diameter through holes in coal mines, installed on the casing (3), characterized in that: Includes a casing clamp (1) and a waterstop plate (2) set at the bottom of the casing clamp (1). The casing clamp (1) is fitted onto the outer wall of the casing (3). The waterstop plate (2) extends horizontally outward from the bottom of the casing clamp (1) to abut against the bottom wall of the through hole and cover the annular gap (31) between the inner wall of the through hole and the outer wall of the casing (3).

2. The coal mine large-diameter through-hole cementing and water-stopping device according to claim 1, characterized in that: The sleeve clamp (1) consists of two opposing half clamps (11), each half clamp (11) has a connecting plate (13) extending from both sides, and the connecting plates (13) of the two half clamps (11) are connected by bolts; the water stop plate (2) is a semi-circular ring, which is fixed to the outer edge of the bottom of the half clamp (11).

3. The coal mine large-diameter through-hole cementing and water-stopping device according to claim 1, characterized in that: The sleeve clamp (1) has a gap with the outer wall of the sleeve (3) and forms an injection cavity (14). The sleeve clamp (1) is equipped with a detachable injection tube (5), which is used to fill the injection slurry with sealant.

4. A coal mine large-diameter through-hole cementing and water-stopping device according to claim 3, characterized in that: The inner wall of the sleeve clamp (1) is rotatably fitted with a ball bearing (15), which is used to abut against the outer wall of the sleeve (3).

5. A coal mine large-diameter through-hole cementing and water-stopping device according to claim 3, characterized in that: The inner wall of the sleeve clamp (1) is provided with an expansion groove (41), and an airbag (4) is installed in the expansion groove (41); the sleeve clamp (1) is provided with a main injection channel (16) and an injection branch channel (17) connected to the main injection channel (16); the main injection channel (16) is also provided with a ventilation groove (42) for connecting to the airbag (4); a sealing component (7) is installed in the injection branch channel (17), and a sliding block (6) is slidably installed in the main injection channel (16). When the sliding block (6) is inserted into the ventilation groove (42), the sealing component (7) opens the injection branch channel (17).

6. A coal mine large-diameter through-hole cementing and water-stopping device according to claim 5, characterized in that: The sealing assembly (7) includes a sealing block (71) and a spring (72). The inner wall of the glue injection channel (17) is provided with a movable groove (74). The sealing block (71) is movably installed in the movable groove (74). The elastic force of the spring (72) is used to drive the sealing block (71) to abut against the inner wall of the glue injection channel (17) away from the movable groove (74). The movable groove (74) is provided with an unlocking groove (75) that communicates with the ventilation groove (42). The outer wall of the sealing block (71) is provided with an unlocking plate (73). One end of the unlocking plate (73) passes through the unlocking groove (75) and enters the ventilation groove (42).

7. A coal mine large-diameter through-hole cementing and water-stopping device according to claim 3, characterized in that: The sleeve clamp (1) is provided with a plug tube (51) for communicating with the main glue injection channel (16), and the glue injection tube (5) is sleeved on the outer wall of the plug tube (51); the plug tube (51) is connected to the glue injection tube (5) through an electromagnetic component.

8. A construction method for a coal mine large-diameter through-hole cementing and water-stopping device based on any one of claims 1-7, characterized in that, Specifically, the following steps are included: S1, insert the casing (3) into the large-diameter through hole. S2, fix the water-stopping device to the bottom of the sleeve (3) so that the water-stopping plate (2) fits against the bottom of the tunnel; S3, small particles of sand and gravel are placed on the ground into the annular gap (31) formed between the inner wall of the through hole and the outer wall of the sleeve (3) to fill the gap; S4, grouting is performed in three stages in the annular gap by inserting a tube for grouting. After each grouting is completed and solidified for 72 hours, the next grouting is performed. S5, cementing completed, check the sealing and water-stopping effect.

9. The construction method of a coal mine large-diameter through-hole cementing and water-stopping device according to claim 8, characterized in that: In step S2, after the casing (3) is installed, a well support is set on the ground for connection with the top of the casing (3).

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