A method for reducing friction and increasing resistance by staggered installation of deep well filling boreholes

Abstract

The present invention provides a method for staggered installation of buffers to reduce friction and increase resistance in deep well filling boreholes, which belongs to the field of mine filling technology. This method drills a vertical filling borehole from the ground level to the deep well, connects with the bottom filling connecting channel, and arranges filling pipes in sections and staggered in the vertical filling borehole of the deep well. The bottom of each filling pipe is a vertical buffer section, and the two adjacent sectioned filling pipes are connected by a horizontal transition section; when the filling slurry is transported to the vertical buffer section, the resistance increases to reduce the excess potential energy of the slurry. After the buffering and resistance increasing effect of the vertical buffer section, the slurry flow rate in the filling pipe is reduced, reducing the wear and scouring of the inner wall of the pipe. This method is beneficial to achieve deep well filling slurry resistance increase and speed reduction, avoids the problems of severe pipe wear and short service life caused by excessive drilling, and greatly shortens the construction period and reduces construction costs.

Description

Technical Field

[0001] The invention relates to the technical field of mine filling, in particular to a method for buffering, reducing friction and increasing resistance by staggered installation of deep well filling boreholes. Background Art

[0002] Backfill drilling is the "throat" project of the backfill system. Its function is to transport the filling slurry from the surface to the underground goaf by gravity or pumping. With the gradual depletion of shallow mineral resources, deep mining of metal mineral resources is an inevitable trend. Due to the great depth of deep well backfill drilling, the filling pipes in the borehole are under great pressure. The process of transporting the filling slurry aggravates the wear and corrosion of the filling pipes. In severe cases, the borehole will be blocked, damaged or even scrapped. Once the backfill borehole is scrapped, a new backfill borehole can only be constructed. This not only directly brings large economic losses to the mine, but also causes serious impacts such as the inability of the entire backfill system to work and stagnation of mine production.

[0003] Existing technologies primarily employ multi-step, switchback piping arrangements, as well as utilizing existing roadways to buffer and increase resistance in vertical filling pipe sections. These multi-step and switchback piping arrangements significantly increase drilling and underground construction workload, and are also challenging to implement. Deep metal mining approaches or exceeds 1,000 meters, with some mines already reaching initial mining depths of 1,500 to 2,000 meters. This makes it difficult to utilize existing roadways for buffering and increasing resistance in vertical filling pipe sections.

[0004] In view of this, the present invention proposes a method for reducing friction and increasing resistance by staggered installation of buffers in deep well filling boreholes, with the purpose of increasing resistance and reducing speed of deep well filling slurry, reducing wear and scouring of the inner wall of the filling pipe by the filling slurry, and improving the service life of the filling borehole. Summary of the Invention

[0005] The present invention provides a method for reducing wear and increasing resistance by staggered installation of buffers in deep well filling boreholes. The filling pipes in the deep well vertical filling boreholes are segmented and arranged in a staggered manner. The deep well filling slurry is increased in resistance and reduced in speed through the vertical buffer sections, thereby solving the problems of severe pipe wear and short service life caused by drilling too deep.

[0006] In order to solve the above-mentioned purpose of the invention, the technical solution provided by the present invention is as follows:

[0007] A deep well filling drilling staggered installation buffering method for reducing friction and increasing resistance includes the following steps:

[0008] S1. Drill a vertical filling borehole from the ground level into the deep well, connect it with the underground filling connecting channel, and the filling pipe enters the underground filling connecting channel from the vertical filling borehole;

[0009] S2. When the vertical filling borehole height exceeds 600m, the filling pipes are arranged in sections and staggered;

[0010] S3. After the filling pipe is installed, since the filling borehole is too deep, the grouting and pipe fixing process adopts the reverse grouting measure at the bottom of the hole to prevent slurry leakage at the bottom. A sealing steel plate is used at the bottom of the vertical filling borehole to seal the gap between the filling pipe and the vertical filling borehole, and a reverse grouting pipe is left on the sealing steel plate;

[0011] S4. Perform reverse grouting at a certain height through the reverse grouting pipe, and then perform surface grouting to fix the pipe after the cement slurry solidifies;

[0012] S5. After the filling pipeline is fixed, the filling slurry is transported from the surface through the filling pipeline to the filling connecting channel. After the filling slurry is buffered and increased in resistance by the vertical buffer section, the slurry flows to the next segmented filling pipeline through the horizontal transition section. The last segmented filling pipeline reaches the filling connecting channel at the bottom of the hole, and then the slurry is transported to the deep well goaf by arranging the filling pipeline.

[0013] As described above, when the filling slurry is transported to the vertical buffer section, the resistance increases and the slurry flow rate is reduced, thereby reducing the wear and scouring of the pipe wall.

[0014] In step S1, the filling borehole is perpendicular to the filling connecting channel, the filling borehole deviation rate does not exceed 0.5% to 1%, and the filling borehole diameter is 500 to 700 mm.

[0015] The outer diameter of the filling pipe in step S1 is 127-168 mm, and the filling pipe is made of seamless steel pipe, bainite pipe, or composite pipe.

[0016] In step S2, when the filling borehole depth is 600m~1000m, the length of each segmented filling pipeline is 300m~400m; when the filling borehole depth is 1000m~2000m, the length of each segmented filling pipeline is 400m~500m; when the filling borehole depth exceeds 2000m, the length of each segmented filling pipeline is 500m;

[0017] Two adjacent sections of the filling pipe are staggeredly arranged in the filling borehole, and the filling pipes are connected by quick joints, welding, and threading.

[0018] The filling pipe is subjected to compressive stress on its wall under the action of high ground stress in the external deep well. In order to enable the cement ring formed by grouting to resist the ground stress, the gap between the vertical filling borehole and the filling pipe is not less than 50mm.

[0019] After the filling pipeline is segmented in step S2, each segmented filling pipeline is 300~500m long, and the lower end of each segmented filling pipeline is a buffer resistance-increasing pipeline, which includes a pipeline tee, a vertical buffer section and a horizontal transition section; during installation, first use the pipeline tee to connect the lower end of the previous segmented filling pipeline, the vertical buffer section and the horizontal transition section, and then connect the horizontal transition section to the upper end of the next segmented filling pipeline through a bend pipe.

[0020] The height of the reverse grouting in step S4 is not less than 2m.

[0021] The length of the vertical buffer section is 0.5m~1m, and the bottom sealing thickness of the vertical buffer section is not less than 0.1m; the length of the horizontal transition section is 146mm~264mm, and the specific length is determined by the borehole diameter and the filling pipe diameter.

[0022] When the distance between the ventilation shaft and the deep well goaf meets the filling slurry transportation requirements, the existing ventilation shaft space is used in step S1 to replace the vertical filling borehole, the filling pipes are staggered along the ventilation shaft, and the filling pipes are fixed to the ventilation shaft wall.

[0023] Compared with the prior art, the above technical solution has at least the following beneficial effects:

[0024] The above scheme arranges filling pipes in sections and staggers in deep well vertical filling boreholes. When the filling slurry is transported to the vertical buffer section, the resistance increases, the slurry flow rate is reduced, and the wear and erosion on the inner wall of the pipe are reduced. This method is beneficial for achieving deep well filling slurry resistance increase and speed reduction, avoiding the problems of severe pipe wear and short service life caused by excessive drilling depth. As the depth of filling wells continues to increase, the traditional mine multi-step and return pipe arrangement buffer resistance increase technology will not be able to solve the problems faced by the drilling section. The present invention increases resistance and reduces wear within the borehole, significantly reducing construction time and cost compared to dedicated roadway resistance reduction between boreholes. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0026] Figure 1 This is a schematic diagram of the arrangement of a deep well filling borehole staggered installation buffer friction reduction and resistance increase method according to the present invention;

[0027] Figure 2 This is a schematic diagram of the buffer resistance-increasing pipeline of the present invention.

[0028] Among them: 1-vertical filling borehole, 2-filling connecting channel, 3-filling pipeline, 4-buffer resistance-increasing pipeline, 5-pipeline tee, 6-vertical buffer section, 7-horizontal transition section, 8-sealing steel plate, 9-reverse grouting pipe. DETAILED DESCRIPTION

[0029] To make the purpose, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the described embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meanings understood by persons of ordinary skill in the art to which this invention pertains. Terms such as "upper," "lower," "left," "right," "front," and "back" as used herein are intended solely to indicate relative positions. These relative positions may change accordingly if the absolute positions of the objects being described change.

[0031] The invention provides a deep well filling borehole staggered installation buffering method for reducing friction and increasing resistance.

[0032] The method is arranged as Figure 1 As shown, the specific steps are as follows:

[0033] S1. Drill a vertical filling borehole 1 from the ground level into the deep well, connect it with the underground filling connecting channel 2, and the filling pipe 3 enters the underground filling connecting channel 2 from the vertical filling borehole 1;

[0034] S2. When the height of the vertical filling borehole 1 exceeds 600 m, the filling pipes 3 are arranged in sections and staggered;

[0035] S3. After the filling pipe 3 is installed, the grouting and pipe fixing process adopts the bottom hole reverse grouting measure. A sealing steel plate 8 is used at the bottom of the vertical filling borehole 1 to seal the gap between the filling pipe 3 and the vertical filling borehole 1. A reverse grouting pipe 9 is left on the sealing steel plate 8.

[0036] S4, reverse grouting is performed at a certain height through the reverse grouting pipe 9, and surface grouting is performed to solidify the pipe after the cement slurry solidifies;

[0037] S5. After the filling pipe 3 is fixed, the filling slurry is transported from the surface through the filling pipe 3 to the filling connecting channel 2. After the filling slurry is buffered and increased in resistance by the vertical buffer section 6, the slurry flows to the next segmented filling pipe through the horizontal transition section 7. The last segmented filling pipe reaches the filling connecting channel at the bottom of the hole, and then the slurry is transported to the deep well goaf by arranging the filling pipeline.

[0038] like Figure 2 After the filling pipeline is segmented in step S2, each segmented filling pipeline is 300~500m long, and the lower end of each segmented filling pipeline is a buffer resistance-increasing pipeline 4, which includes a pipeline tee 5, a vertical buffer section 6 and a horizontal transition section 7; during installation, first use the pipeline tee 5 to connect the lower end of the previous segmented filling pipeline, the vertical buffer section 6 and the horizontal transition section 7, and then connect the horizontal transition section 7 to the upper end of the next segmented filling pipeline through a bend pipe.

[0039] When the distance between the ventilation shaft and the deep well goaf meets the filling slurry transportation requirements, the existing ventilation shaft space is used in step S1 to replace the vertical filling borehole, the filling pipes are staggered along the ventilation shaft, and the filling pipes are fixed to the ventilation shaft wall.

[0040] The following describes this with reference to specific embodiments.

[0041] A mine with a mining depth of 1200m adopts the backfill mining method. To solve the problems of severe pipe wear and short service life caused by excessively deep drilling, a deep well backfill drilling staggered installation buffering method for reducing friction and increasing resistance is adopted. The specific process includes the following steps:

[0042] S1: Drill a vertical filling borehole 1 from the ground level into the deep well, connecting with the underground filling connecting channel 2. The borehole diameter is 600 mm. During the drilling construction, the borehole is kept vertical as much as possible, and the borehole deviation rate does not exceed 1%. The cross-sectional structure of the vertical filling borehole 1 is that a filling pipe 3 is installed in the borehole. The outer diameter of the pipe is 159 mm. The filling pipe is made of seamless steel pipe, and the pipes are connected by threaded threads;

[0043] S2: The vertical filling borehole 1 is 1200m high, and the filling pipeline is divided into three sections and arranged in a staggered manner. Each section of the filling pipeline is 400m long, with a buffer and resistance-increasing pipeline 4 at the lower end. During installation, the vertical buffer section 6 and the horizontal transition section 7 are first connected using a pipe tee 5 to complete the connection of the buffer and resistance-increasing pipeline 4. The length of the vertical buffer section 6 is 1m, and the bottom of the vertical buffer section is sealed with a thickness of 0.1m. The gap between the vertical filling borehole 1 and the filling pipeline 3 is 60mm. The length of the horizontal transition section 7 is 162mm. The horizontal transition section 7 of the buffer and resistance-increasing pipeline 4 is then connected to the lower section of the filling pipeline through a bend pipe, and then the upper section of the pipeline is connected to the upper end of the pipe tee 5.

[0044] S3: After the filling pipe 3 is installed, since the filling borehole 1 is too deep, a reverse grouting measure can be taken in the grouting and pipe fixing process to prevent slurry leakage at the bottom. A sealing steel plate 8 is used at the bottom of the hole to seal the gap between the filling pipe 3 and the vertical filling borehole 1. The sealing steel plate 8 has a reverse grouting pipe 9. First, a certain amount of reverse grouting is carried out. The height of the reverse grouting is about 3m. After the high-grade cement slurry solidifies, surface grouting and pipe fixing are carried out. Grouting is stopped until cement slurry overflows from the orifice of the vertical filling borehole 1, and grouting is carried out according to the settlement of the cement slurry.

[0045] S4: The filling slurry is transported from the surface to the deep well goaf through the filling pipe 3. When the filling slurry is transported to the vertical buffer section 6, the resistance increases and the slurry flow rate is reduced, thereby reducing the wear and erosion of the pipe wall.

[0046] S5: After buffering and increasing resistance in the vertical buffer section 6, the slurry flows to the next section through the horizontal transition section 7. The filling pipeline of the last section reaches the filling connecting channel 2 at the bottom of the hole, and then the filling slurry is transported to the deep well goaf by arranging the filling pipeline.

[0047] There are a few points to note:

[0048] (1) The drawings of the embodiments of the present invention only relate to the structures related to the embodiments of the present invention. Other structures may refer to conventional designs.

[0049] (2) In the absence of conflict, the embodiments of the present invention and the features therein may be combined with each other to form new embodiments.

[0050] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. The protection scope of the present invention shall be based on the protection scope of the claims.

Claims

1. A deep well filling drilling staggered installation buffering method for reducing friction and increasing resistance, characterized in that: The steps are as follows: S1. Drill a vertical filling borehole from the ground level into the deep well, connect it with the underground filling connecting channel, and the filling pipe enters the underground filling connecting channel from the vertical filling borehole; S2. When the vertical filling borehole height exceeds 600m, the filling pipes are arranged in sections and staggered; S3. After the filling pipe is installed, the grouting and pipe fixing process adopts the bottom hole reverse grouting measure, and the gap between the filling pipe and the vertical filling borehole is sealed with a sealing steel plate at the bottom of the vertical filling borehole, and a reverse grouting pipe is left on the sealing steel plate; S4. Perform reverse grouting at a certain height through the reverse grouting pipe, and then perform surface grouting to fix the pipe after the cement slurry solidifies; S5. After the filling pipe is fixed, the filling slurry is transported from the surface through the filling pipe to the filling connecting channel. After the filling slurry is buffered and increased in resistance by the vertical buffer section, the slurry flows through the horizontal transition section to the next segmented filling pipe. The last segmented filling pipe reaches the filling connecting channel at the bottom of the hole, and then the slurry is transported to the deep well goaf through the arrangement of the filling pipeline; After the filling pipeline is segmented in step S2, each segmented filling pipeline is 300-500m long, and the lower end of each segmented filling pipeline is a buffer resistance-increasing pipeline, which includes a pipeline tee, a vertical buffer section, and a horizontal transition section. During installation, the pipeline tee is first used to connect the lower end of the previous segmented filling pipeline, the vertical buffer section, and the horizontal transition section, and then the horizontal transition section is connected to the upper end of the next segmented filling pipeline through an elbow. When the distance between the ventilation shaft and the deep well goaf meets the filling slurry transportation requirements, the existing ventilation shaft space is used in step S1 to replace the vertical filling borehole, the filling pipes are staggered along the ventilation shaft, and the filling pipes are fixed to the ventilation shaft wall.

2. The deep well filling drilling staggered installation buffering friction reduction and resistance increasing method according to claim 1 is characterized in that: In step S1, the filling borehole is perpendicular to the filling connecting channel, the filling borehole deviation rate does not exceed 0.5% to 1%, and the filling borehole diameter is 500 to 700 mm.

3. The deep well filling drilling staggered installation buffering friction reduction and resistance increasing method according to claim 1 is characterized in that: The outer diameter of the filling pipe in step S1 is 127-168 mm, and the filling pipe is made of seamless steel pipe, bainite pipe, or composite pipe.

4. The deep well filling drilling staggered installation buffering friction reduction and resistance increasing method according to claim 1 is characterized in that: In step S2, when the filling borehole depth is 600m~1000m, the length of each segmented filling pipeline is 300m~400m; when the filling borehole depth is 1000m~2000m, the length of each segmented filling pipeline is 400m~500m; when the filling borehole depth exceeds 2000m, the length of each segmented filling pipeline is 500m; Two adjacent sections of the filling pipe are staggeredly arranged in the filling borehole, and the filling pipes are connected by quick joints, welding, and threading.

5. The deep well filling drilling staggered installation buffering friction reduction and resistance increasing method according to claim 1 is characterized in that: The gap between the vertical filling borehole and the filling pipe is not less than 50 mm.

6. The deep well filling drilling staggered installation buffering friction reduction and resistance increasing method according to claim 1 is characterized in that: The height of the reverse grouting in step S4 is not less than 2m.

7. The deep well filling drilling staggered installation buffering friction reduction and resistance increasing method according to claim 1 is characterized in that: The length of the vertical buffer section is 0.5m~1m, and the bottom sealing thickness of the vertical buffer section is not less than 0.1m; the length of the horizontal transition section is 146mm~264mm.

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