Variable-diameter segmented directional static inflation fracturing filling device and method

Abstract

This invention discloses a variable-diameter segmented directional static expansion fracturing filling device and method, relating to the technical field of mining filling equipment. The filling device includes a material mixing mechanism and a filling mechanism. The filling mechanism includes a pneumatic filling device and a filling pipe. The filling pipe includes a fixed-diameter pipe, a variable-diameter pipe, and a pipe diameter adjustment disc, with the pipe diameter adjustment disc positioned between the fixed-diameter pipe and the variable-diameter pipe. The variable-diameter pipe is coaxially arranged with the fixed-diameter pipe and is formed by multiple circumferentially distributed flat plates, with adjacent plates overlapping vertically. The pipe diameter adjustment disc includes a circular base, a drive ring, and triangular diameter reducing plates. Each flat plate of the variable-diameter pipe is vertically fixedly installed on the corresponding triangular diameter reducing plate. This invention uses a stepless variable-diameter filling pipe, enabling stepless adjustment of the orifice diameter of conventional hard rock fracturing filling pipes, solving the problem of poor versatility of fixed-diameter devices.

Description

Technical Field

[0001] This invention relates to the field of mining filling equipment technology, specifically to a variable-diameter segmented directional static expansion fracturing filling device and method. Background Technology

[0002] In geotechnical engineering projects such as mining, tunneling, and rock slope treatment, hard rock fracturing is one of the core procedures. Static expansion fracturing technology is widely used in scenarios where blasting operations are strictly limited due to its advantages such as no blasting vibration, no flyrock, no noise, and no pollution.

[0003] However, existing static expansion fracturing filling devices and processes have the following technical defects: 1. The discharge mechanism of the filling device is mostly a fixed diameter structure, which cannot be adapted to drilling operations with different hole diameters, resulting in poor versatility; some variable diameter structures have problems such as insufficient sealing, uneven discharge, and easy hole jamming. 2. Current construction methods mostly use full-hole one-time filling of expansion agent, which makes it difficult to control the fracturing direction of hard rock, resulting in poor directional fracturing effect, and it is also impossible to carry out differentiated fracturing design for complex hard rock strata with uneven joint development and large lithological variations. Therefore, a new filling device and method are urgently needed to improve filling efficiency and fracturing effect. Summary of the Invention

[0004] To address the aforementioned problems, this invention discloses a variable-diameter segmented directional static expansion fracturing filling device and method. It employs a stepless variable-diameter filling pipe, which enables stepless adjustment of the orifice diameter of conventional hard rock fracturing filling pipes, thus solving the problem of poor versatility of fixed-diameter devices. At the same time, it proposes a segmented alternating precise filling method to improve the fracturing effect.

[0005] A variable-diameter segmented directional static expansion fracturing filling device according to the present invention includes a material mixing mechanism and a filling mechanism. The filling mechanism includes a pneumatic filling device and a filling pipe. The filling pipe includes a fixed-diameter pipe, a variable-diameter pipe, and a pipe diameter adjusting plate. One end of the fixed-diameter pipe is fixedly connected to the pipe diameter adjusting plate, and the other end is equipped with an air pipe connector and connected to the pneumatic filling device through the air pipe connector. An inlet is opened on the pipe wall of the fixed-diameter pipe connected to the pipe diameter adjusting plate, and the mixing outlet pipe of the material mixing mechanism is connected through the inlet. The variable-diameter pipe is arranged on the side of the pipe diameter adjusting plate away from the fixed-diameter pipe and is coaxially arranged with the fixed-diameter pipe. The variable-diameter pipe is formed by multiple circumferentially distributed flat plates, with adjacent flat plates overlapping vertically. The pipe diameter adjustment disc includes a circular base, a drive ring, and triangular reducing plates. One end face of the circular base is fixedly connected to a fixed diameter pipe, and the other end face has multiple grooves evenly distributed around its circumference. The drive ring is rotatably connected to the circular base, and the end face of the drive ring has multiple through arc-shaped holes evenly distributed around its circumference. The triangular reducing plates are disposed between the circular base and the drive ring, with multiple plates evenly distributed around the circumference of the circular base. Adjacent triangular reducing plates are in contact with each other. Each triangular reducing plate has a slider on its end face near the circular base and a guide rod on its other end face. The slider is placed in the corresponding groove and slides within it, and the guide rod is placed in the arc-shaped hole. Each plate of the variable diameter pipe is vertically fixedly installed on the corresponding triangular reducing plate. The number of grooves, arc-shaped holes, triangular reducing plates, and plates is the same.

[0006] Preferably, the drive ring has an integrally formed cylindrical sidewall, and the drive ring is sleeved on the circular ring base through the cylindrical sidewall and connected to the circular ring base by a bearing; a handle is arranged on the outer periphery of the drive ring.

[0007] Preferably, the slider is a T-shaped slider, and the cross-section of the groove is T-shaped to fit the slider; the end of the guide rod away from the triangular reducing plate is externally threaded and screwed with a nut.

[0008] Preferably, the inner diameter of the annular base is the same as the inner diameter of the fixed diameter pipe, the inner diameter of the fixed diameter pipe is the same as the minimum inscribed circle diameter of the variable diameter pipe, and the inner diameter of the drive ring is the same as the maximum circumscribed circle diameter of the variable diameter pipe.

[0009] Preferably, the overlapping surface between the lower side of each plate and the adjacent plate is an inclined surface, and the edge of the upper side away from the adjacent plate is rounded.

[0010] Preferably, the variable diameter pipe is assembled from multiple pipe sections, with adjacent sections fixed together by bolts.

[0011] Preferably, the pneumatic filling device includes an air compressor and an air pipe, the air pipe is connected to the air compressor and the air pipe connector, and the air pipe is equipped with a pressure gauge and a pressure regulating valve.

[0012] Preferably, the material mixing mechanism includes two spiral mixing mechanisms, which respectively mix the expanding agent and the slurry; each spiral mixing mechanism includes a hopper, a spiral agitator, and a discharge channel; the discharge channels of the two spiral mixing mechanisms are connected to a mixing discharge pipe.

[0013] Another method disclosed in this invention for filling using the aforementioned variable-diameter segmented directional static expansion cracking filling device includes the following steps: S1. Based on the fracturing design scheme, construct pre-diameter holes on the target hard rock. R Hole depth LFor the fracturing borehole, high-pressure air was used to remove rock powder and residue. The borehole sight was then activated, and the probe was slowly lowered to the bottom of the borehole at a uniform speed. The sight acquired real-time images of the rock mass at different depths within the borehole. Based on the lithology and rock mass integrity at different depths, a full-hole lithology distribution profile was generated, obtaining the length of the fracturing section along the borehole depth. L i With the length of the blocking section B i Data; simultaneously, based on lithology and on-site temperature, the optimal water-to-agent ratio and dosage of static expansion agent were selected for each fractured segment. Q i The optimal water-to-material ratio and amount of clay were selected for each sealing section. W i ; S2. Assemble the quick-release four-legged bracket mechanism, place it at the drill hole opening, level and secure it; adjust according to the drill hole diameter. R The diameter of the variable diameter pipe is adjusted by adjusting the pipe diameter adjustment disc to match the maximum outer diameter of the adjusted variable diameter pipe with the borehole diameter; according to the borehole depth, the corresponding number of variable diameter pipes are spliced ​​together, and the water supply, gas supply and power supply systems of the device are connected. The device is then started up and debugged to ensure that all components are operating normally. S3. Prepare the required gunning mud and static expansion agent through two spiral stirring mechanisms; S4. Open the static expansion agent discharge valve and inject the amount of static fracturing agent for the first fracturing stage into the borehole at the preset discharge rate. Q 1. Complete the compaction of the current fracturing section; close the static expansion agent discharge valve, open the stemming mud discharge valve, and inject the required amount of stemming mud for the first sealing section into the borehole. W 1. Complete the filling of the first sealing section and close the taphole mud discharge valve. The expansion pressure is completely restricted within the corresponding fracturing section through the taphole mud sealing section to achieve directional fracturing. S5. Repeat steps S3 and S4 for filling the fracturing and plugging sections. Perform alternating filling operations in sections from the bottom of the hole to the hole opening. Complete the alternating filling of all fracturing and plugging sections in the entire borehole until the designed position at the hole opening is reached. The entire hole filling is then complete.

[0014] Preferably, in S1, the amount of static expansion agent used in the fracture-inducing segment is... Q i The calculation formula is: In the formula: Q i -No. i Dosage of static expansion agent for fractured segments, kg; q 1 - Static expansion agent dosage per unit length, kg / m; γ 1-The loss rate of static expansion agent is 0.05~0.1; L i -No. i Length of the segmental fracture, in meters; ρ 1-Wet density of the static expanding agent after mixing, kg / m³ 3 ; R- The borehole diameter is generally 0.032 m to 0.050 m; Cementing amount of blasting mud in the sealing section W i The calculation formula is: In the formula: W i -No. i The amount of blasting mud used in the sealing section, in kg; q 2 - Clay usage per unit length, kg / m; γ 2- The loss rate of the taphole clay is 0.05~0.1; B i -No. i Length of the blocking section, in meters; ρ 2-Wet density of the mixing mud, kg / m³ 3 ;; R- The borehole diameter is generally 0.032 m to 0.05 m.

[0015] Compared with the prior art, the advantages of the variable diameter segmented directional static expansion cracking filling device and method disclosed in this invention are: (1) The present invention adopts a stepless variable diameter filling pipe, which can achieve arbitrary continuous and smooth adjustment within the commonly used hole diameter range, adapting to the hole diameter deviation and multi-specification drilling that are common in hard rock drilling construction, and solving the problem of poor versatility of fixed diameter devices; moreover, the filling pipe adopts a standard section modular design, which can be freely spliced ​​and combined according to the actual depth of different holes, and can meet the drilling construction needs of different depths, providing reliable technical support for efficient and low-cost construction of hard rock fracturing engineering.

[0016] (2) This invention is equipped with two spiral stirring mechanisms to stir the expanding agent and the stemming mud respectively, which can realize the segmented and precise filling of static expanding agent and stemming mud. The area and direction of the expansion pressure are precisely controlled by the stemming mud sealing section, which perfectly adapts to the directional fracturing requirements of complex hard rock formations with uneven joint development and large lithological changes. It solves the problem of poor directional fracturing effect of the existing full-hole filling method, and the fracturing direction is highly controllable. At the same time, this invention can dynamically match the optimal water-agent ratio and admixture parameters according to the lithological differences of rock masses at different depths, avoiding the problem of fracturing failure caused by improper ratio. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall structure of a variable-diameter segmented directional static expansion cracking filling device disclosed in this invention.

[0019] Figure 2 This is a schematic diagram of the internal structure of a variable-diameter segmented directional static expansion cracking filling device disclosed in this invention.

[0020] Figure 3 This is a schematic diagram of the filling tube structure.

[0021] Figure 4 This is a schematic diagram showing the installation of the drive ring and the triangular reducer plate.

[0022] Figure 5 This is a schematic diagram showing the installation of the fixed base with the triangular reducing plate.

[0023] Figure 6 This is a schematic diagram of the flat plate structure for the intermediate pipeline.

[0024] In the diagram: 1-Material mixing mechanism; 11-Pooling mud hopper; 12-Pooling mud mixing chamber; 13-Pooling mud spiral mixing blades; 14-Pooling mud discharge channel; 15-Static expanding agent hopper; 16-Static expanding agent mixing chamber; 17-Static expanding agent spiral mixing blades; 18-Static expanding agent discharge channel; 19-Mixed discharge pipe; 110-First water inlet; 111-Second water inlet; 2-Fixed diameter pipe; 3-Pipe diameter adjusting plate; 31-Circular ring base; 311-Slide groove; 32-Drive ring; 321-Arc-shaped hole; 33-Triangular reducing plate; 331-Guide rod; 332-Nut; 333-Slider; 34-Handle; 4-Variable diameter pipe; 41-Threaded fixing hole; 42-Groove; 43-Protrusion; 5-Control system; 6-Quick-release four-legged bracket mechanism. Detailed Implementation

[0025] The specific embodiments of the present invention will be briefly described below with reference to the accompanying drawings. Obviously, the described embodiments are merely some, not all, embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0026] Figures 1-6 A preferred embodiment of the present invention is shown and analyzed in detail.

[0027] like Figure 1 , 2 The variable diameter segmented directional static expansion cracking filling device shown includes a material stirring mechanism 1 and a filling mechanism, the filling mechanism including a pneumatic filling device and a filling pipe.

[0028] Among them, such as Figure 3 As shown, the filling pipe includes a fixed diameter pipe 2, a variable diameter pipe 4, and a pipe diameter adjustment plate 3. The pipe diameter adjustment plate 3 is located between the fixed diameter pipe 2 and the variable diameter pipe 4, and includes a circular base 31, a drive ring 32, and a triangular diameter reducing plate 33.

[0029] One end of the fixed-diameter pipe 2 is fixedly connected to the annular base 31 on the pipe diameter adjusting plate 3 via a flange, and the other end is equipped with an air pipe connector, which is connected to the pneumatic filling equipment. The pneumatic filling equipment includes an air compressor and an air pipe, with the air pipe connecting the air compressor and the air pipe connector. The air pipe is equipped with a pressure gauge and a pressure regulating valve. An inlet is opened on the wall of the fixed-diameter pipe 2 at the end connected to the pipe diameter adjusting plate 3, and the mixing outlet pipe 19 of the material mixing mechanism 1 is fixedly connected to the inlet. The material, after being mixed by the material mixing mechanism 1, enters the filling pipe through the mixing outlet pipe 19 and the inlet, and is then fed into the borehole by the pneumatic filling equipment.

[0030] The variable diameter pipe 4 is located on the side of the pipe diameter adjustment plate 3 away from the fixed diameter pipe 2, and is coaxially arranged with the fixed diameter pipe 2. The variable diameter pipe 4 is surrounded by ten circumferentially distributed flat plates, with adjacent plates overlapping vertically. The pipe diameter of the variable diameter pipe 4 can be adjusted by adjusting the relative position of the adjacent plates. The overlapping surface of the lower side of each plate with the adjacent plate is inclined, and the edge of the upper side away from the adjacent plate is rounded to facilitate better insertion into the borehole. The variable diameter pipe 4 is assembled from multiple pipe sections, and adjacent sections are fixed together with bolts. Specifically, the variable diameter pipe 4 includes a first pipe section, a last pipe section, and multiple intermediate pipe sections, such as... Figure 6 As shown, a groove 42 is provided at one end of the plate of the intermediate pipeline, and a protrusion 43 that mates with the groove 42 is provided at the other end. Both the groove 42 and the protrusion 43 are provided with threaded fixing holes 41. The plate of two adjacent intermediate pipeline sections is fixed to each other by first fitting the groove 42 and the protrusion 43 together, aligning them with the threaded fixing holes 41, and then installing bolts to tighten them. One end of the plate of the first pipeline section is a smooth surface, which is fixedly connected to the pipe diameter adjustment plate 3, and the other end is provided with a groove 42 to be fixedly connected to the plate of the intermediate pipeline. The plate of the last pipeline section is provided with a protrusion 43 at one end to be fixedly connected to the corresponding plate of the intermediate pipeline, and the other end is a smooth surface.

[0031] like Figure 4 , 5As shown, one end face of the annular base 31 on the pipe diameter adjusting disc 3 is connected to the fixed diameter pipe 2 via a flange, and the other end face has multiple T-shaped grooves 311 evenly distributed circumferentially. The drive ring 32 is coaxially arranged with the annular base 31, and the end face of the drive ring 32 has multiple through arc-shaped holes 321 evenly distributed circumferentially. Specifically, the drive ring 32 has an integrally formed cylindrical sidewall, and the drive ring 32 is sleeved on the annular base 31 through the cylindrical sidewall and connected to the annular base 31 by a bearing; a handle 34 is arranged on the outer periphery of the drive ring 32, and the drive ring 32 can be rotated by the handle 34. Triangular reducing plates 33 are disposed between the annular base 31 and the drive ring 32, with multiple plates evenly distributed around the circumference of the annular base 31. Adjacent triangular reducing plates 33 fit together. Each triangular reducing plate 33 has a T-shaped slider 333 that mates with a T-shaped groove 311 on its end face near the annular base 31, and a guide rod 331 on its other end face. The slider 333 is placed in the corresponding groove 311 and slides within it. The guide rod 331 is placed in the arc-shaped hole 321. Specifically, the end of the guide rod 331 away from the triangular reducing plate 33 has an external thread and is screwed with a nut 332. When the drive ring 32 is rotated to adjust the diameter of the variable diameter pipe 4 to a suitable size, the nut 332 is tightened. The friction between the nut 332 and the drive ring 32 fixes the position of the guide rod 331 in the arc-shaped hole 321, thereby achieving a limit and preventing the pipe diameter from shrinking back. At the same time, by reasonably designing the length of the arc-shaped hole 321, the adjustment range of the diameter of the variable diameter pipe 4 can be controlled. The variable diameter pipe 4 is vertically mounted on the corresponding triangular reducing plate 33 by welding. Specifically, the end of the first section of the variable diameter pipe 4 furthest from the middle section is welded to the triangular reducing plate 33. The number of sliding grooves 311, arc-shaped holes 321, triangular reducing plates 33, and flat plates is the same. The inner diameter of the annular base 31 is the same as the inner diameter of the fixed diameter pipe 2. The inner diameter of the fixed diameter pipe 2 is the same as the inner diameter of the smallest adjustable diameter of the variable diameter pipe 4. The inner diameter of the drive ring 32 is the same as the maximum outer diameter of the variable diameter pipe 4. In this invention, the diameter of the variable diameter pipe 4 can be adjusted steplessly within a small range, suitable for use in multiple filling boreholes with small diameter differences. If the diameter difference of the filling boreholes is too large, it is recommended to directly replace the filling pipe.

[0032] The material mixing mechanism 1 includes two spiral mixing mechanisms, which respectively mix the expanding agent and the drilling mud. Specifically, as shown... Figure 1 , 2As shown, the slurry mixing mechanism for taphole clay and the slurry mixing mechanism for static expansion agent are arranged side by side above the filling pipe. The slurry mixing mechanism for taphole clay includes a taphole clay hopper 11, a slurry agitator for taphole clay, and a taphole clay discharge channel 14. A sealing cover for the taphole clay hopper 11 is hinged to the top to prevent material splashing during mixing, and a discharge valve for the taphole clay hopper 11 is located below it. The slurry agitator for taphole clay is located at the discharge end below the taphole clay hopper 11. The slurry agitator for taphole clay includes a mixing chamber 12 and slurry agitator blades 13, which can achieve uniform mixing of materials. A discharge valve for taphole clay is located below the mixing chamber 12 and is connected to the discharge channel 14. A first water inlet 110 is provided on the upper side wall of the mixing chamber 12, and an electrically controlled flow regulating valve is installed at the first water inlet 110 for precise control of the water inlet. The static expanding agent spiral mixing mechanism includes a static expanding agent hopper 15, a static expanding agent spiral agitator, and a static expanding agent discharge channel 18. A sealing cover is hinged to the top of the static expanding agent hopper 15 to prevent material splashing during mixing, and a discharge valve is located below it. The static expanding agent spiral agitator is located at the discharge end below the static expanding agent hopper 15. The static expanding agent spiral agitator includes a static expanding agent mixing chamber 16 and static expanding agent spiral mixing blades 17, enabling uniform mixing of materials. A static expanding agent discharge valve is located below the static expanding agent mixing chamber 16 and connects to the static expanding agent discharge channel 18. A second water inlet 111 is provided on the upper side wall of the static expanding agent mixing chamber 16, and an electrically controlled flow regulating valve is installed at the second water inlet 111 for precise control of the water inlet volume. Temperature and humidity sensors are installed on the top of the inner walls of both the clay mixing chamber 12 and the static expanding agent mixing chamber 16 to monitor the temperature and humidity of the mixture in real time. The slurry discharge channel 14 and the static expansion agent discharge channel 18 are arranged in a Y-shape and are connected to the mixing discharge pipe 19.

[0033] like Figure 1 As shown, a quick-release four-legged support mechanism 6 is also fixedly installed below the two spiral mixing mechanisms. The quick-release four-legged support mechanism 6 is made of aluminum alloy and includes four retractable legs. It can be quickly disassembled and folded to adapt to different construction sites. At the same time, the height and level of the device can be adjusted to ensure stability during construction.

[0034] The entire filling device shares a common control system 5, which is fixedly installed behind the mixing mechanism. The control system 5 includes a main power switch, a display, and a PLC controller, which are used to control the start and stop of the mixer, monitor the temperature and humidity inside the mixing chamber, regulate the water inlet, and control the pneumatic filling equipment.

[0035] Another method disclosed in this invention for filling using the aforementioned variable-diameter segmented directional static expansion cracking filling device includes the following steps: S1. Based on the fracturing design scheme, construct pre-diameter holes on the target hard rock. R Hole depth L For the fracturing borehole, high-pressure air was used to remove rock powder and residue. The borehole sight was then activated, and the probe was slowly lowered to the bottom of the borehole at a uniform speed. The sight acquired real-time images of the rock mass at different depths within the borehole. Based on the lithology and rock mass integrity at different depths, a full-bore lithology distribution profile was generated, and the length of the fracturing section along the borehole depth was rationally determined. L i With the length of the blocking section B i Data; simultaneously, based on lithology and on-site temperature, the optimal water-to-agent ratio and dosage of static expansion agent were selected for each fractured segment. Q i The optimal water-to-material ratio and amount of clay were selected for each sealing section. W i ; Dosage of static expansion agent for fractured segment Q i The calculation formula is: In the formula: Q i -No. i Dosage of static expansion agent for fractured segments, kg; q 1 - Static expansion agent dosage per unit length, kg / m; γ 1-The loss rate of static expansion agent is 0.05~0.1; L i -No. i Length of the segmental fracture, in meters; ρ 1-Wet density of the static expanding agent after mixing, kg / m³ 3 ; R- The borehole diameter is generally 0.032 m to 0.050 m; Cementing amount of blasting mud in the sealing section W i The calculation formula is: In the formula: W i -No. i The amount of blasting mud used in the sealing section, in kg; q 2 - Clay usage per unit length, kg / m; γ2- The loss rate of the taphole clay is 0.05~0.1; B i -No. i Length of the blocking section, in meters; ρ 2-Wet density of the mixing mud, kg / m³ 3 ;; R- The borehole diameter is generally 0.032 m to 0.05 m.

[0036] S2. Assemble the quick-release four-legged bracket mechanism 6, place it at the drill hole opening, level it, and secure it; adjust the drilling diameter accordingly. R The diameter of the variable diameter pipe 4 is adjusted by the pipe diameter adjustment disc 3 so that the maximum outer diameter of the adjusted variable diameter pipe 4 matches the borehole diameter; according to the borehole depth, the corresponding number of variable diameter pipes 4 are spliced ​​together, and the water supply, gas supply and power supply systems of the device are connected. The device is then started up and debugged to ensure that all components are operating normally. S3. Add dry tapping clay powder and dry static expansion agent powder to tapping clay hopper 11 and static expansion agent hopper 15 respectively, and cover the sealing caps of tapping clay hopper 11 and static expansion agent hopper 15; open the discharge valve of tapping clay hopper 11 and pour the tapping clay of the first sealing section into tapping clay mixing chamber 12. W 1. Open the discharge valve of the static expansion agent hopper 15 and pour the amount of static fracturing agent for the first fracturing stage into the static expansion agent mixing chamber 16. Q 1； According to the set water-to-agent ratio, the corresponding mass of clean water is injected into the corresponding mixing chamber through the first water inlet 110 and the second water inlet 111 respectively; the spiral mixing blades 13 for the mud and the spiral mixing blades 17 for the static expansion agent are started and stirred at the specified speed and duration; during the stirring process, the temperature and humidity sensors in the mixing chamber monitor the temperature and humidity of the material in real time, and the PLC controller adjusts the stirring speed and stirring duration in real time; after the stirring is completed, the spiral mixing blades are turned off. S4. Open the static expansion agent discharge valve and output the amount of static fracturing agent required for the first fracturing stage through the static expansion agent discharge channel 18 and the mixing discharge pipe 19 at a preset discharge rate. Q 1. The material is transferred to a fixed diameter pipeline 2 and injected into the borehole using a pneumatic filling device to complete the compaction of the current fracturing section. The static expansion agent discharge valve is closed, and the stemming material discharge valve is opened. The stemming material for the first sealing section is injected into the borehole in the same manner as the static expansion agent. W 1. Complete the filling of the first sealing section and close the taphole mud discharge valve. The expansion pressure is completely restricted within the corresponding fracturing section through the taphole mud sealing section to achieve directional fracturing. S5. Repeat steps S3 and S4 for filling the fracturing and plugging sections, performing alternating filling operations from the bottom of the hole to the opening. Continue this alternating filling of all fracturing and plugging sections throughout the borehole until the designed opening position is reached, completing the full borehole filling. During the filling operation, the entire machine is moved backward and the filling pipe is retracted while filling. After retracting a certain distance, part of the intermediate pipe on the variable diameter pipe 4 can be removed to continue filling.

[0037] The above description of the disclosed embodiments enables those skilled in the art to make and use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit and scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A variable-diameter segmented directional static expansion fracturing filling device, characterized in that, The system includes a material mixing mechanism (1) and a filling mechanism. The filling mechanism includes a pneumatic filling device and a filling pipe. The filling pipe includes a fixed diameter pipe (2), a variable diameter pipe (4), and a pipe diameter adjustment plate (3). One end of the fixed diameter pipe (2) is fixedly connected to the pipe diameter adjustment plate (3), and the other end is equipped with an air pipe connector and connected to the pneumatic filling device through the air pipe connector. An inlet is opened on the pipe wall of the fixed diameter pipe (2) connected to the pipe diameter adjustment plate (3), and the inlet is connected to the mixing outlet pipe (19) of the material mixing mechanism (1). The variable diameter pipe (4) is located on the side of the pipe diameter adjustment plate (3) away from the fixed diameter pipe (2) and is coaxial with the fixed diameter pipe (2). The variable diameter pipe (4) is formed by multiple circumferentially distributed flat plates, with adjacent flat plates overlapping vertically. The pipe diameter adjustment disc (3) includes a circular base (31), a drive ring (32), and a triangular reducing plate (33); one end face of the circular base (31) is fixedly connected to the fixed diameter pipe (2), and the other end face has multiple grooves (311) evenly distributed around its circumference; the drive ring (32) is rotatably connected to the circular base (31), and the end face of the drive ring (32) has multiple through arc-shaped holes (321) evenly distributed around its circumference; the triangular reducing plate (33) is disposed between the circular base (31) and the drive ring (32), and multiple plates are evenly distributed around the circumference of the circular base (31), with adjacent plates... The triangular diameter reducing plates (33) are fitted together. Each triangular diameter reducing plate (33) has a slider (333) on the end face near the circular base (31) and a guide rod (331) on the other end face. The slider (333) is placed in the corresponding groove (311) and slides therein. The guide rod (331) is placed in the arc hole (321). Each plate of the variable diameter pipeline (4) is vertically fixed on the corresponding triangular diameter reducing plate (33). The number of grooves (311), arc holes (321), triangular diameter reducing plates (33) and plates is the same.

2. The variable-diameter segmented directional static expansion fracturing filling device according to claim 1, characterized in that, The drive ring (32) has an integrally formed cylindrical sidewall. The drive ring (32) is sleeved on the circular base (31) through the cylindrical sidewall and is connected to the circular base (31) by bearing. A handle (34) is arranged on the outer periphery of the drive ring (32).

3. The variable-diameter segmented directional static expansion fracturing filling device according to claim 2, characterized in that, The slider (333) is a T-shaped slider, and the cross-section of the groove (311) is T-shaped to fit the slider (333); the guide rod (331) has an external thread at the end away from the triangular reducing plate (33) and is screwed with a nut (332).

4. The variable-diameter segmented directional static expansion fracturing filling device according to claim 1, characterized in that, The inner diameter of the circular base (31) is the same as the inner diameter of the fixed diameter pipe (2), the inner diameter of the fixed diameter pipe (2) is the same as the minimum inscribed circle diameter of the variable diameter pipe (4), and the inner diameter of the drive ring (32) is the same as the maximum circumscribed circle diameter of the variable diameter pipe (4).

5. The variable-diameter segmented directional static expansion fracturing filling device according to claim 1, characterized in that, The overlapping surface between the lower side of each plate and the adjacent plate is an inclined surface, and the edge of the upper side away from the adjacent plate is rounded.

6. The variable-diameter segmented directional static expansion fracturing filling device according to claim 1, characterized in that, The variable diameter pipeline (4) is assembled from multiple pipeline sections, with adjacent sections fixed together by bolts.

7. The variable-diameter segmented directional static expansion fracturing filling device according to claim 1, characterized in that, The pneumatic filling device includes an air compressor and an air pipe. The air pipe connects the air compressor and the air pipe connector. The air pipe is equipped with a pressure gauge and a pressure regulating valve.

8. The variable-diameter segmented directional static expansion fracturing filling device according to claim 1, characterized in that, The material mixing mechanism (1) includes two spiral mixing mechanisms, which respectively mix the expanding agent and the slurry; each spiral mixing mechanism includes a hopper, a spiral agitator and a discharge channel; the discharge channels of the two spiral mixing mechanisms are connected to the mixing discharge pipe (19).

9. A method for filling using the variable-diameter segmented directional static expansion fracturing filling device according to any one of claims 1-8, characterized in that, Includes the following steps: S1. Based on the fracturing design scheme, construct pre-diameter holes on the target hard rock. R Hole depth L For the fracturing borehole, high-pressure air was used to remove rock powder and residue. The borehole sight was then activated, and the probe was slowly lowered to the bottom of the borehole at a uniform speed. The sight acquired real-time images of the rock mass at different depths within the borehole. Based on the lithology and rock mass integrity at different depths, a full-hole lithology distribution profile was generated, obtaining the length of the fracturing section along the borehole depth. L i With the length of the blocking section B i Data; simultaneously, based on lithology and on-site temperature, the optimal water-to-agent ratio and dosage of static expansion agent were selected for each fractured segment. Q i The optimal water-to-material ratio and amount of clay were selected for each sealing section. W i ; S2. Assemble the quick-release four-legged bracket mechanism (6), place it at the borehole opening, level and fix it; according to the borehole diameter R The diameter of the variable diameter pipe (4) is adjusted by the pipe diameter adjustment plate (3) so that the maximum outer diameter of the adjusted variable diameter pipe (4) matches the borehole diameter; according to the borehole depth, the corresponding number of variable diameter pipes (4) are spliced ​​together, and the water supply, gas supply and power supply systems of the device are connected. The machine is started and debugged to ensure that all components are operating normally. S3. Prepare the required gunning mud and static expansion agent through two spiral stirring mechanisms; S4. Open the static expansion agent discharge valve and inject the amount of static fracturing agent for the first fracturing stage into the borehole at the preset discharge rate. Q 1. Complete the compaction of the current fracturing section; close the static expansion agent discharge valve, open the stemming mud discharge valve, and inject the required amount of stemming mud for the first sealing section into the borehole. W 1. Complete the filling of the first sealing section and close the taphole mud discharge valve. The expansion pressure is completely restricted within the corresponding fracturing section through the taphole mud sealing section to achieve directional fracturing. S5. Repeat steps S3 and S4 for filling the fracturing and plugging sections. Perform alternating filling operations in sections from the bottom of the hole to the hole opening. Complete the alternating filling of all fracturing and plugging sections in the entire borehole until the designed position at the hole opening is reached. The entire hole filling is then complete.

10. The method according to claim 9, characterized in that, In S1, the amount of static expansion agent used in the fracture segment Q i The calculation formula is: In the formula: Q i -No. i Dosage of static expansion agent for fractured segments, kg; q 1 - Static expansion agent dosage per unit length, kg / m; γ 1-The loss rate of static expansion agent is 0.05~0.1; L i -No. i Length of the segmental fracture, in meters; ρ 1-Wet density of the static expanding agent after mixing, kg / m³ 3 ; R- The borehole diameter is generally 0.032 m to 0.050 m; Cementing amount of blasting mud in the sealing section W i The calculation formula is: In the formula: W i -No. i The amount of blasting mud used in the sealing section, in kg; q 2 - Clay usage per unit length, kg / m; γ 2- The loss rate of the taphole clay is 0.05~0.1; B i -No. i Length of the blocking section, in meters; ρ 2-Wet density of the mixing mud, kg / m³ 3 ;; R- The borehole diameter is generally 0.032 m to 0.05 m.

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