Mining three-blocking two-injecting hole packer

Abstract

The utility model discloses a mining three-plugging two-injection hole packer which comprises an assembly hole sealing pipeline used for being arranged in a coal seam drill hole to extract gas, and the assembly hole sealing pipeline is sleeved with a first bag, a second bag and a third bag. The grouting pipe and the assembled hole sealing pipeline are arranged in parallel, and a pipe body of the grouting pipe sequentially penetrates through the first bag, the second bag and the third bag; the inlet end of the grouting pipe is located on the outer side of the first bag, the outlet end of the grouting pipe is located in the third bag, and flow dividing ports are formed in the junction of the grouting pipe and the first bag and the junction of the grouting pipe and the second bag. Explosion valves are arranged at the positions, between the first bag and the second bag and between the second bag and the third bag, of the grouting pipe. The problems that in an existing two-blocking and one-injecting technology, grout is prone to flowing away along the large position of a crack in the grouting process of the area where a blocking section close to the outer side is located, and the crack is not prone to being completely blocked are solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of mine hole - sealing devices, and particularly relates to a mine three - plug two - injection hole - sealing device.

Background Art

[0002] In the prior art, the "two - plug one - injection" method for mines is a pressure - assisted hole - sealing method. Its principle is to first seal both ends of the hole - sealing section of the coal - seam borehole with bladder bags, and then inject slurry into the borehole section between the two sealed sections through a grouting pipe. This method can effectively fill the cracks around the borehole and improve the gas extraction efficiency. However, in the area where the outer sealing section is located, due to the relatively severe development of fissures and their wide distribution range, during the grouting process, the slurry is likely to flow away along the larger fissures, and it is not easy to completely seal all the fissures.

Content of the Utility Model

[0003] The purpose of the utility model is to provide a mine three - plug two - injection hole - sealing device to solve the problem that in the existing two - plug one - injection process, in the area where the outer sealing section is located, the slurry is likely to flow away along the larger fissures during the grouting process, and it is not easy to completely seal all the fissures.

[0004] The utility model adopts the following technical solutions: A mine three - plug two - injection hole - sealing device includes an assembled hole - sealing pipeline for placing in a coal - seam borehole to extract gas. The assembled hole - sealing pipeline is sleeved with a first bladder bag, a second bladder bag, and a third bladder bag; the first bladder bag, the second bladder bag, and the third bladder bag are respectively located at the outer end, the middle section, and the inner end of the assembled hole - sealing pipeline;

[0005] It also includes a grouting pipe arranged in parallel with the assembled hole - sealing pipeline. The pipe body of the grouting pipe sequentially passes through the first bladder bag, the second bladder bag, and the third bladder bag; the inlet end of the grouting pipe is located outside the first bladder bag, the outlet end of the grouting pipe is located inside the third bladder bag, and diversion ports are arranged at the intersections of the grouting pipe with the first bladder bag and the second bladder bag;

[0006] On the grouting pipe: Blasting valves are arranged at the positions between the first bladder bag and the second bladder bag, and between the second bladder bag and the third bladder bag;

[0007] Among them, the first bladder bag, the second bladder bag, and the third bladder bag are used to seal the borehole by internal grouting expansion, and form an outer - section hole - sealing space between the first bladder bag and the second bladder bag, and form an inner - section hole - sealing space between the second bladder bag and the third bladder bag; the blasting valves are used to blast under set pressure conditions to inject and fill the outer - section hole - sealing space and the inner - section hole - sealing space respectively.

[0008] Further, the preset pressure of the blasting valve between the first bladder bag and the second bladder bag is 1.5 MPa.

[0009] Further, the preset pressure of the blasting valve between the second bladder bag and the third bladder bag is 0.8 MPa.

[0010] Further, the assembled hole-sealing pipeline includes multiple hole-sealing pipes connected in series, and the adjacent hole-sealing pipes are connected by threads.

[0011] The beneficial effects of the utility model are as follows: by setting three sacs, the grouting section is divided into two sections, namely an inner hole-sealing space and an outer hole-sealing space; in the area where the outer hole-sealing space is located, due to the relatively serious development of fissures and the wide distribution range, during the grouting process, the grout is likely to flow away along the larger fissures and it is not easy to completely seal all the fissures. Therefore, the outer section mainly plays the role of filling the borehole. The fissures in the inner section space are relatively less developed, which is convenient for realizing high-pressure grouting hole-sealing and can better achieve effective sealing of the fissures, enhancing the borehole sealing performance, so as to achieve the purpose of improving the gas drainage effect.

Description of the Drawings

[0012] Figure 1 is a schematic structural diagram of the mine-used three-block two-injection hole-sealing device of the utility model;

[0013] Figure 2 is Figure 1 an enlarged view of part A in

[0014] Figure 3 is a schematic diagram of the use state of the mine-used three-block two-injection hole-sealing device of the utility model.

[0015] Among them, 1. hole-sealing pipe, 2. grouting pipe, 21. inlet end, 22. outlet end, 23. shunt port, 24. pipe body, 3. blasting valve, 4. first sac, 5. second sac, 6. third sac.

Specific Embodiments

[0016] The utility model will be described in detail below in conjunction with the drawings and specific embodiments.

[0017] The utility model provides a mine-used three-block two-injection hole-sealing device. As Figure 1 shown, it includes an assembled hole-sealing pipeline for placing in a borehole to extract gas, and the assembled hole-sealing pipeline is sheathed with a first sac 4, a second sac 5 and a third sac 6; the first sac 4, the second sac 5 and the third sac 6 are respectively located at the outer end, the middle section and the inner end of the assembled hole-sealing pipeline.

[0018] It further includes a grouting pipe 2 arranged in parallel with the assembled hole-sealing pipeline. The pipe body of the grouting pipe 2 passes through the first sac 4, the second sac 5 and the third sac 6 in sequence; the inlet end 21 of the grouting pipe 2 is located outside the first sac 4, the outlet end 22 of the grouting pipe 2 is located inside the third sac 6, and shunt ports 23 are arranged at the intersections of the grouting pipe 2 and the first sac 4 and the second sac 5. As Figure 2As shown, the shunt port 23 is an opening provided on the grouting pipe 2 for shunting and injecting the slurry into the bladder. The grouting pipe 2 is used to grout into the first bladder 4 and the second bladder 5 through two shunt ports 23 thereon, and is also used to grout into the third bladder 6 through its outlet end 22; the first bladder 4, the second bladder 5 and the third bladder 6 are used to seal the borehole by their own expansion.

[0019] On the grouting pipe 2, blasting valves 3 are provided at positions between the first bladder 4 and the second bladder 5, and between the second bladder 5 and the third bladder 6.

[0020] Among them, the first bladder 4, the second bladder 5 and the third bladder 6 are used to seal the borehole by internal grouting and expansion. The expanded bladder can effectively support the borehole, form a high-stress area around the sealed section of the borehole, avoid continuous generation of cracks after sealing the hole, and form an air leakage channel.

[0021] An outer section sealing space is formed between the first bladder 4 and the second bladder 5, and an inner section sealing space is formed between the second bladder 5 and the third bladder 6. The outer section sealing space mainly functions to fill the borehole. The inner section sealing space has relatively less developed cracks, which is convenient for realizing high-pressure grouting sealing of the hole, can better effectively seal the cracks, can enhance the borehole sealing performance, and thus achieve the purpose of improving the gas drainage effect.

[0022] The blasting valve 3 is used to blast under the set pressure conditions to grout and fill the outer section sealing space and the inner section sealing space respectively.

[0023] In some embodiments, the preset pressure of the blasting valve 3 between the first bladder 4 and the second bladder 5 is 1.5 MPa.

[0024] In some embodiments, the preset pressure of the blasting valve 3 between the second bladder 5 and the third bladder 6 is 0.8 MPa.

[0025] In some embodiments, the assembled hole-sealing pipeline includes a plurality of hole-sealing pipes 1 connected in series, and the adjacent hole-sealing pipes 1 are threadedly connected. The length of the assembled hole-sealing pipeline can be adjusted according to the actual borehole conditions underground.

[0026] The using method of the mine-used three-block two-injection hole-sealing device of the present utility model is as follows:

[0027] Place both the assembled hole-sealing pipeline and the grouting pipe 2 into the coal seam borehole;

[0028] Connect the grouting pipe 2 to the grouting pump, and the slurry quickly enters the first bladder 4, the second bladder 5 and the third bladder 6 due to the grouting pressure;

[0029] As Figure 3As shown, three pockets quickly expand. Their outer wall surfaces are fastened to the inner wall of the coal seam borehole, and their inner wall surfaces are fastened to the outer surface of the assembled hole - sealing pipeline, thereby sealingly forming an outer - section hole - sealing space and an inner - section hole - sealing space on the assembled hole - sealing pipeline;

[0030] After the three pockets are filled and support the borehole to form two grouting spaces, namely the outer - section hole - sealing space and the inner - section hole - sealing space, continuous grouting is carried out. The pressure slowly increases to 0.8 Mp. First, the blasting valve between the second pocket 5 and the third pocket 6 opens, and the inner - section hole - sealing space starts grouting. After the inner - section hole - sealing space is filled, when the pressure continues to increase to 1.5 Mp, the blasting valve between the first pocket 4 and the second pocket 5 opens, and the outer - section hole - sealing space starts grouting; The grout fills the outer - section hole - sealing space and the inner - section hole - sealing space. After the grout completely solidifies, gas drainage is carried out through the assembled hole - sealing pipeline.

[0031] Through the comparative analysis of 50 groups of borehole experimental data, for the boreholes using the "three - plug two - injection" hole - sealing device, the average single - hole gas drainage concentration within 15 days is 39.14% higher than that of the boreholes using the "two - plug one - injection" hole - sealing device. After 75 days of drainage, the average gas concentration of the "three - plug two - injection" is 58.87% higher than that of the "two - plug one - injection" boreholes. On average, more than 1 low - concentration ineffective borehole can be reduced for every 50 boreholes. At present, the "three - plug two - injection" hole - sealing technology has been comprehensively promoted and used in the mine. Calculated according to 8500 boreholes constructed throughout the year, 170 ineffective boreholes can be reduced throughout the year. The combined labor and material cost for single - hole construction of cross - seam boreholes is about 8000 yuan, and on average, more than 1.36 million yuan of capital waste can be reduced throughout the year.

Claims

1. The three-blocking and two-injection hole sealer for mining is characterized by: The invention comprises an assembled sealing pipe for being placed in a coal seam borehole to extract gas, wherein the assembled sealing pipe is covered with a first bag (4), a second bag (5) and a third bag (6); the first bag (4), the second bag (5) and the third bag (6) are respectively located at the outer end, the middle section and the inner end of the assembled sealing pipe; It also comprises a grouting pipe (2) arranged in parallel with the assembled sealing pipe, the pipe body of the grouting pipe (2) passes through the first bag (4), the second bag (5) and the third bag (6) in sequence; the inlet end (21) of the grouting pipe (2) is located outside the first bag (4), the outlet end (22) of the grouting pipe (2) is located inside the third bag (6), and the intersection of the grouting pipe (2) with the first bag (4) and the second bag (5) is provided with a diversion port (23); On the grouting pipe (2), burst valves (3) are provided at positions between the first bag (4) and the second bag (5), and between the second bag (5) and the third bag (6); The first bag (4), the second bag (5) and the third bag (6) are used to seal the borehole by internal grouting expansion, and to form an outer sealing space between the first bag (4) and the second bag (5), and an inner sealing space between the second bag (5) and the third bag (6); the bursting valve (3) is used to burst under set pressure conditions to inject grout into the outer sealing space and the inner sealing space respectively.

2. The three-blocking and two-injection hole sealer for mining according to claim 1, characterized in that: The preset pressure of the burst valve (3) between the first bladder bag (4) and the second bladder bag (5) is 1.5 MPa.

3. The three-blocking and two-injection hole sealer for mining as claimed in claim 1 is characterized in that: The preset pressure of the burst valve (3) between the second bladder (5) and the third bladder (6) is 0.8 MPa.

4. The three-blocking and two-injection hole sealer for mining as claimed in claim 1 or 2, characterized in that: The assembled sealing pipe comprises a plurality of sealing pipes (1) connected in series, and adjacent sealing pipes (1) are threadedly connected.

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