A system and method for drilling high-pressure grouting displacement

Abstract

This invention discloses a high-pressure grouting displacement system for boreholes, comprising a storage pipe, a conversion pipe, and a cementing casing arranged coaxially from top to bottom. A first gate valve is installed between the storage pipe and the conversion pipe, and a second gate valve is installed between the conversion pipe and the cementing casing. The lower end of the cementing casing extends into the grouting borehole. A flow-disrupting plug is installed inside the storage pipe, forming an annular channel between the outer wall of the flow-disrupting plug and the inner wall of the storage pipe. The system also includes a three-way valve, the first channel of which connects to a grouting pump, the second channel of which connects to the upper port of the storage pipe via a second grouting hose, and the third channel of which connects to a grouting interface on the conversion pipe via a third grouting hose. This invention cleans the cement slurry adhering to the borehole wall during grouting by using the flow-disrupting plug, increasing the effective flow cross-sectional area of ​​the borehole, reducing grouting pressure, improving the displacement effect during the grouting displacement stage, improving grouting efficiency and displacement effect, and reducing the workload of post-grouting borehole cleaning.

Description

Technical Field

[0001] This invention belongs to the field of coal mine water control technology, specifically relating to a system and method for replacing cement slurry in borehole grouting holes. Background Technology

[0002] In existing technologies, the treatment of formation water-conducting fractures and channels typically involves drilling to expose the water-conducting channels on the surface or underground, followed by high-pressure grouting. The aim is to use the cementing effect of the cement to seal the water-conducting channels, thereby increasing the thickness of the aquitard, reducing the amount of water flowing into the mine, and ensuring safe production. Specifically, this involves: first, drilling into the aquifer or a predetermined location to explore and expose the water-conducting channels. When the outflow (leakage) exceeds the designed grouting outflow (leakage), cement slurry is injected from the borehole using a grouting pump or other power equipment through a grouting pipeline. Under pressure, the cement slurry enters the water-conducting fractures along the borehole and expands, gradually filling and sealing the water-conducting channels. As the channels are blocked and the cement slurry solidifies, the grouting pressure gradually increases. When the designed grouting end pressure is reached, a water injection process begins, injecting a certain amount of clean water to replace the cement slurry in the borehole, reducing the difficulty and workload of subsequent borehole cleaning. After replacing to the predetermined amount, the replacement is stopped, the borehole valve is closed, and the water is allowed to solidify. After the borehole pressure returns to zero, drilling and sweeping continue. Grouting is repeated when the water output (leakage) reaches the designed level. This process is repeated until the predetermined position is reached. The above method has the following main drawbacks: Due to the inherent characteristics of the fluid and the adhesive force of the cement slurry, the flow velocity of the cement slurry varies across the borehole cross-section during grouting. The flow velocity is faster at the center of the borehole cross-section and slower near the borehole wall, causing cement slurry to adhere to the borehole wall and gradually solidify. After prolonged grouting, the adhered and solidified cement slurry gradually reduces the flow cross-section, leading to a gradual increase in grouting pressure, and even pump stalling, resulting in low grouting efficiency. During the water displacement stage, a significant portion of the cement slurry near the borehole wall cannot be replaced by water. During the pressure release and cessation of displacement, the incompletely solidified cement slurry flows slowly under gravity, eventually accumulating and solidifying at a relatively low point in the borehole. This increases the workload of subsequent borehole sweeping and easily leads to borehole trajectory deviation during later sweeping processes, resulting in drilling new holes. Summary of the Invention

[0003] To address the deficiencies and shortcomings of existing technologies, this invention provides a drilling grouting replacement system and method. By intermittently removing cement slurry adhering to the borehole wall during the grouting process, it solves the technical problems of low grouting efficiency and large workload of subsequent borehole cleaning caused by the accumulation and solidification of grouting material on the borehole wall in existing technologies.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A drilling high-pressure grouting replacement system includes a storage pipe, a conversion pipe, and a cementing casing arranged coaxially from top to bottom. A first gate valve is provided between the storage pipe and the conversion pipe, and a second gate valve is provided between the conversion pipe and the cementing casing. The lower end of the cementing casing extends into the grouting borehole.

[0006] The storage tube is equipped with a flow-turbing sealing plug, and an annular channel is formed between the outer wall of the flow-turbing sealing plug and the inner wall of the storage tube.

[0007] It also includes a three-way valve, the first channel of which can be connected to the grouting pump via a first grouting hose, the second channel of which is connected to the upper port of the storage pipe via a second grouting hose, and the third channel of which is connected to the grouting interface opened on the conversion pipe via a third grouting hose.

[0008] During grouting operations, cement slurry enters the grouting borehole through the third grouting hose, the conversion pipe, and the cementing casing.

[0009] When pushing the turbulence-prone packer, the injected fluid first enters the storage pipe through the second grouting hose, pushing the turbulence-prone packer into the conversion pipe, and then enters the conversion pipe through the third grouting hose, pushing the turbulence-prone packer into the grouting borehole.

[0010] The present invention also has the following technical features:

[0011] Specifically, a third gate valve is also provided on the second grouting hose, and a fourth gate valve is also provided on the third grouting hose.

[0012] Furthermore, the turbulence-causing plug is made of concrete with added polypropylene fibers, using the same type of cement as the grouting cement; the polypropylene fibers are added at a dosage of 0.5-0.6 kg / m³ based on the volume of the turbulence-causing plug. 3 The polypropylene fiber is cylindrical in shape and has a length of 6mm to 50mm.

[0013] Furthermore, the turbulence-blocking plug includes an integrally connected hemispherical plug head and a cylindrical plug body, with multiple trapezoidal grooves arranged circumferentially on the outer surface of the plug body.

[0014] Furthermore, the length of the turbulence-blocking plug is 0.4 to 0.7 meters, and the length of the turbulence-blocking plug is greater than 5.5 times the plug body diameter.

[0015] Furthermore, the depth of the trapezoidal groove is 0.3 to 0.6 times the diameter of the plug body, and the ratio of the length of the lower base of the trapezoidal groove to the depth of the trapezoidal groove is greater than 1.8, and the spacing between adjacent trapezoidal grooves is 0.5 to 1.3 times the diameter of the plug body.

[0016] Furthermore, the conversion tube has a pressure relief port on its wall, and a pressure gauge is also installed on the wall of the conversion tube.

[0017] This invention also protects a high-pressure grouting displacement method for boreholes, the method being implemented using the aforementioned high-pressure grouting displacement system for boreholes, and comprising the following steps:

[0018] Step 1: Complete the drilling of the vertical well section of the grouting borehole. At least one cementing casing is installed in the vertical well section, and the cementing casing extends along the length of the vertical well section, connecting the cementing casing and the transition pipe.

[0019] Step 2: Determine the diameter of the turbulence-causing plug based on the diameter of the grouting borehole, and complete the prefabrication of the turbulence-causing plug. The diameter of the grouting borehole is 5-10 mm larger than the diameter of the turbulence-causing plug.

[0020] Step 3: Complete the drilling construction of the grouting section of the grouting borehole, and obtain the water output data in real time during the drilling process. After the water output reaches the design grouting value, continue drilling for 10-15m.

[0021] Step 4: Complete the connection between the grouting pump, storage pipe, and conversion pipe. Then, flush the hole with clean water at a flow rate of 0.5 to 0.7 m / s until the water injection volume reaches 1.5 to 2.5 times the total volume of the grouting borehole.

[0022] Step 5: Perform grouting operation. During the grouting operation, push the turbulence sealing plug through the conversion pipe into the grouting borehole at set time intervals. The grouting operation ends when the grouting time reaches the set value.

[0023] Step 6: Clean water injection operation. During the clean water injection operation, push the turbulence sealing plug into the grouting borehole through the conversion pipe at the set time intervals. Stop the water injection when the water volume reaches 1.5 to 2.5 times the total volume of the grouting borehole. The clean water injection operation is then completed.

[0024] Step 7: After the grouting material has reached its set time, perform hole cleaning.

[0025] Furthermore, step 5, which involves pushing the turbulence-causing plug through the conversion pipe into the grouting borehole at set time intervals, specifically includes: when the cement slurry density is 1.2 g / cm³. 3 The time interval was 6 hours; the density was 1.3 g / cm³. 3 The time interval was 5.5 hours; the density was 1.4 g / cm³. 3 The time interval was 5 hours; the density was 1.5 g / cm³. 3 The time interval is 4.5 hours.

[0026] Compared with the prior art, the beneficial technical effects of this invention are:

[0027] (1) The system of the present invention provides a pre-installation space for the turbulence sealing plug through structural design. The pressure release and turbulence sealing plug push operation can be realized through the cooperation of the conversion pipe and the grouting pipeline. The turbulence sealing plug provided by the present invention can effectively remove cement slurry adhering to the borehole wall through structural design, especially the parameter design of the trapezoidal groove. The device of the present invention has a simple structure, is easy to install and use, and can save maintenance costs. It is worth promoting.

[0028] (2) In this invention, only the conversion pipe and the grouting hose are high pressure, and the conversion pipe is connected to other pipes by flanges on both sides, which has a high safety factor; the grouting pipe has a low diameter and a high pressure resistance factor; the high pressure part is separated from the low pressure part such as the storage pipe by the gate valve, and the overall pipeline has a high pressure resistance and safety factor.

[0029] (3) The method of the present invention cleans the cement slurry attached to the borehole wall by using a turbulence-blocking plug during the grouting process, thereby increasing the effective flow cross-sectional area of ​​the borehole, reducing the grouting pressure, and improving the grouting efficiency and grouting quality; it also improves the displacement effect in the displacement stage, reduces the subsequent hole cleaning workload, reduces cement consumption, and reduces the hole cleaning workload. Attached Figure Description

[0030] Figure 1 This is a schematic diagram of the overall structure of the system of the present invention;

[0031] Figure 2 This is a schematic diagram of the structure of the turbulence-blocking plug;

[0032] Figure 3 A schematic diagram illustrating the stages of pushing the turbulence-causing seal plug;

[0033] Figure 4 Schematic diagram of the turbulence seal plug entering the grouting borehole;

[0034] Figure 5 Schematic diagram I showing the disturbance caused by the flow-disrupting packer within the grouting borehole;

[0035] Figure 6 Schematic diagram II showing the disturbance caused by the flow-disrupting packer within the grouting borehole.

[0036] Meaning of the symbols in the attached image:

[0037] 1-Storage pipe, 2-Conversion pipe, 3-Cementing casing, 4-First gate valve, 5-Second gate valve, 6-Turbulence seal plug, 7-Three-way valve, 8-Second grouting hose, 9-Third grouting hose, 10-Third gate valve, 11-Fourth gate valve, 12-Pressure gauge, 13-First grouting hose;

[0038] 21-Pressure relief port;

[0039] 61-Plug head, 62-Plug body, 621-Trapezoidal groove.

[0040] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. Detailed Implementation

[0041] Following the above technical solutions, specific embodiments of the present invention are given below. It should be noted that the present invention is not limited to the following specific embodiments, and all equivalent modifications made based on the technical solutions of this application fall within the protection scope of the present invention. The present invention will be further described in detail below with reference to the embodiments.

[0042] When describing the orientation of this invention, it should be understood that the terms "up," "down," "front," "back," "left," and "right," etc., indicate orientation or positional relationships only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0043] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" may explicitly or implicitly include one or more of that feature.

[0044] In this invention, unless otherwise stated, the terms "installation," "connection," "linking," and "fixing" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0045] It should be noted that, unless otherwise specified, all components involved in this embodiment are components that can be purchased in the prior art.

[0046] Example 1

[0047] Following the above technical solutions, such as Figures 1 to 4As shown, this embodiment provides a borehole high-pressure grouting replacement system, including a storage pipe 1, a conversion pipe 2, and a cementing casing 3 arranged coaxially from top to bottom. Depending on the geological conditions, one-section, two-section, three-section, or more-section cementing casings can be selected. A first gate valve 4 is installed between the storage pipe 1 and the conversion pipe 2, and a second gate valve 5 is installed between the conversion pipe 2 and the cementing casing 3. The lower end of the cementing casing 3 extends into the grouting borehole. The inner cavity of the storage pipe 1 forms a storage chamber for storing a flow-disrupting packer 6, the diameter of which is smaller than the inner diameter of the storage pipe 1, forming an annular channel between the outer wall of the flow-disrupting packer 6 and the inner wall of the storage pipe 1. During the grouting replacement process, the flow-disrupting packer 6 is pushed into the grouting borehole. When subsequent drilling begins after grouting, the flow-disrupting packer 6 is cut and broken by the drill bit, and the debris is discharged from the borehole along with drilling fluids such as mud, without affecting subsequent construction.

[0048] The drilling high-pressure grouting replacement system also includes a three-way valve 7. During grouting, the first channel of the three-way valve 7 can be connected to the grouting pump via the first grouting hose 13, the second channel of the three-way valve 7 is connected to the upper port of the storage pipe 1 via the second grouting hose 8, and the third channel of the three-way valve 7 is connected to the grouting interface opened on the conversion pipe 2 via the third grouting hose 9. In this embodiment, the grouting interface is opened on the side wall of the conversion pipe 2.

[0049] As a preferred embodiment, a third gate valve 10 is also provided on the second grouting hose 8, and a fourth gate valve 11 is also provided on the third grouting hose 9.

[0050] During grouting operations, the first gate valve 4 and the third gate valve 10 are closed. The cement slurry sequentially passes through the three-way valve 7, the third grouting hose 9, the fourth gate valve 11, the switching pipe 2, the second gate valve 5, and the cementing casing 3 into the grouting borehole.

[0051] When pushing the turbulence-prone packer 6, first close the fourth gate valve 11 and open the third gate valve 10. The fluid injected through the three-way valve 7 first enters the storage pipe 1 through the second grouting hose 8. The turbulence-prone packer 6, which is pre-installed in the storage pipe, is pushed into the switching pipe 2 through the opened first gate valve 4. Then, close the first gate valve 4 and the third gate valve 10, and open the fourth gate valve 11. The fluid enters the switching pipe 2 through the third grouting hose 9 and pushes the turbulence-prone packer 6 into the grouting borehole. At this time, there is no pressure in the storage pipe. The turbulence-prone packer 6 can be put in again through the opening at the top of the storage pipe 1 to prepare for the next push.

[0052] Cement slurry enters the grouting borehole through the third grouting hose 9, the conversion pipe 2, and the cementing casing 3;

[0053] When pushing the turbulence-causing plug 6, by controlling the opening and closing of each gate valve, the injected fluid can first enter the storage pipe 1 through the second grouting hose 8, pushing the turbulence-causing plug 6 into the conversion pipe 2, and then enter the conversion pipe 2 through the third grouting hose 9, pushing the turbulence-causing plug 6 into the grouting borehole. In this embodiment, the fluid includes water and cement slurry. The gate valves and pipelines can be connected by flanges.

[0054] As a preferred embodiment, the turbulence-causing plug 6 is made of concrete with added polypropylene fibers, wherein the polypropylene fiber content is 0.5-0.6 kg / m³ based on the volume of the turbulence-causing plug. 3 The polypropylene fibers are cylindrical in shape and range in length from 6mm to 50mm. The function of the polypropylene fibers is to increase the tensile strength of the turbulence packer and prevent localized damage or breakage during the displacement process.

[0055] In a preferred embodiment, the turbulence-blocking plug 6 includes an integrally connected hemispherical plug head 61 and a cylindrical plug body 62. Multiple trapezoidal grooves 621 are provided circumferentially on the outer surface of the plug body 62. The diameter of the hemisphere is the same as the diameter of the cylinder, and the diameter is determined according to the borehole diameter.

[0056] As a preferred embodiment, the length of the turbulence-blocking plug 6 is 0.6 meters due to the limitations of the orifice device and the length of the storage tube. If the length is too large, it will reduce the overall strength of the turbulence-blocking plug, increase the friction between the plug body and the orifice wall, and increase the risk of jamming. In addition, the length of the turbulence-blocking plug 6 is greater than 5.5 times the diameter of the plug body.

[0057] As a preferred embodiment, the depth of the trapezoidal groove 621 is 0.3 to 0.6 times the diameter of the plug body, and the ratio of the length of the bottom of the trapezoidal groove 621 to the depth of the trapezoidal groove 621 is greater than 1.8, and the spacing between adjacent trapezoidal grooves 621 is 0.5 to 1.3 times the diameter of the plug body.

[0058] As a preferred embodiment, the conversion pipe 2 has a pressure relief port 21 on its wall, and a pressure gauge 12 is also provided on its wall.

[0059] As a preferred embodiment, the distance between the outer wall of the plug 62 and the inner wall of the storage tube 1 is 5mm to 10mm.

[0060] In this embodiment, numerical simulation was used to simulate the shape of the turbulence-causing packer. The simulation data mainly included: cement slurry density 1.4 g / cm³. 3 (The specific gravity of the cement grout used for grouting is 1.2 to 1.5), the borehole diameter is 120 mm, the length of the turbulence seal plug is 660 mm, and the liquid flow velocity in the hole is 3.5 m / s.

[0061] Final comparative simulations show that when the depth of the trapezoidal groove 621 is 0.3 to 0.6 times the diameter of the plug body, and the ratio of the length of the lower base of the trapezoidal groove 621 to its depth is greater than 1.8, and the spacing between adjacent trapezoidal grooves 621 is 0.5 to 1.3 times the diameter of the plug body, the removal effect on cement slurry from the borehole wall is better. Considering material strength, the spacing between the turbulence-causing seal plug recesses is set to 1 times the diameter, and the depth is set to 0.25 times the diameter.

[0062] In addition, such as Figure 5 and Figure 6 As shown, before and after the turbulence packer passes through, the color of the hole wall to the center of the hole is very dark and the color value is relatively uniform, indicating that the cement slurry content in the hole is relatively uniform. Under this condition, the cement slurry in the hole is in a laminar flow state. The cement slurry adhering near the hole wall is affected by the hole wall, the flow rate is slow, and it is easy to slowly adhere and solidify.

[0063] Within a certain distance after the turbulence-blocking plug 6 passes, the fluid state inside the orifice fluctuates to varying degrees. As can be seen from the figure, the fluid inside the orifice is significantly disturbed after the turbulence-blocking plug 6 passes, so the originally relatively stable and uniform flow state is disturbed, and it returns to a stable state after the turbulence-blocking plug 6 passes a certain distance.

[0064] In summary, the use of the turbulence-sealing plug 6 inside the borehole can clean and replace cementitious substances such as cement slurry adhering to the borehole wall by creating disturbance inside the borehole. Especially in the clear water replacement stage, the turbulence-sealing plug 6 can effectively improve the replacement effect.

[0065] Example 2

[0066] Following the above technical solution, this embodiment provides a borehole high-pressure grouting displacement method, which is implemented using the coal mine underground high-pressure grouting displacement system provided in Embodiment 1, and includes the following steps:

[0067] Step 1: Complete the drilling of the vertical well section for grouting. In this embodiment, a 120mm diameter drill bit and an 89mm diameter drill pipe are used. At least one cementing casing is installed in the vertical well section, and the cementing casing extends along the length of the vertical well section. After the drilling trajectory enters the designed layer, when the water flow (leakage) in the borehole reaches the designed grouting threshold, continue drilling for 10-15m, then pull out the drill string. After the drill string is pulled out, keep the second gate valve open to allow the water in the hole to flow out of the hole and discharge the residual rock cuttings in the hole with the water flow. Close the second gate valve and connect the cementing casing to the conversion pipe.

[0068] In this embodiment, the first casing uses a casing with a diameter of 194mm, the second casing uses a casing with a diameter of 146mm, and the third borehole has a diameter of 120mm, using open-hole drilling. The second, first, fourth, and third gate valves are all DN200 / 40 type gate valves with an inner diameter of 200mm, allowing drill bits and other drilling tools to pass through. The conversion pipe and storage pipe both use casing with a diameter of 146mm. The turbulence-sealing plug is 660mm long and 110mm in diameter, with a trapezoidal groove depth of 55mm, a lower base length of 110mm, and an upper base length of 55mm.

[0069] Step 2: Determine the diameter of the turbulence-causing plug based on the diameter of the grouting borehole, and complete the prefabrication of the turbulence-causing plug. The diameter of the grouting borehole is 5-10 mm larger than the diameter of the turbulence-causing plug.

[0070] Step 3: Complete the drilling construction of the grouting section of the grouting borehole, and obtain the water output data in real time during the drilling process. After the water output reaches the design grouting value, continue drilling for 10-15m.

[0071] Step 4: Complete the connection between the grouting pump, storage pipe, and conversion pipe. Then, flush the hole with clean water at a flow rate of 0.5 to 0.7 m / s until the water injection volume reaches 1.5 to 2.5 times the total volume of the grouting borehole.

[0072] Step 5: Perform grouting operation. During the grouting operation, push the turbulence sealing plug through the conversion pipe into the grouting borehole at set time intervals. The grouting operation ends when the grouting time reaches the set value.

[0073] Specifically, this includes: when the density of the cement paste is 1.2 g / cm³. 3 The time interval was 6 hours; the density was 1.3 g / cm³. 3 The time interval was 5.5 hours; the density was 1.4 g / cm³. 3 The time interval was 5 hours; the density was 1.5 g / cm³. 3 The time interval is 4.5 hours.

[0074] First, keep the pressure relief port 21 and the first gate valve 4 closed, and open the fourth gate valve 11. Turn on the grouting pump or other grouting power equipment. The cement slurry enters the borehole through the first grouting hose 13, the three-way valve 7, the fourth gate valve 11, the conversion pipe 2, the second gate valve 5 and the cementing casing 3, and finally enters the water-producing fracture. During the grouting process, open the conversion interface, place the turbulence sealing plug 6 into the storage pipe 1, and then close the conversion interface.

[0075] After the predetermined grouting time is reached, grouting is paused, the second gate valve 5 is closed, the pressure relief port 21 is opened to release the cement slurry pressure in the conversion pipe 2, and the reading of the pressure gauge 12 installed on the conversion pipe 2 is observed. When the reading is 0, the fourth gate valve 11 is closed, the third gate valve 10 and the first gate valve 4 are opened, and the grouting pump is started. The cement slurry passes through the three-way valve 7, the second grouting hose 8, the third gate valve 10, and the storage pipe 1, pushing the turbulence-prone sealing plug 6 through the first gate valve 4 into the conversion pipe 2. The grouting pump is paused again, the first gate valve 4 and the third gate valve 10 are closed, the fourth valve 11 is opened, the pressure relief port 21 is closed, the second valve 5 is opened, and the grouting pump is started. The cement slurry pushes the turbulence-prone sealing plug 6 into the cementing casing 3. Because the turbulence-prone sealing plug 6 is close to the borehole diameter, during the movement of the cement slurry pushing the turbulence-prone sealing plug 6, the unsolidified cement slurry adhering to the borehole wall is disturbed and pushed towards the bottom of the borehole, reducing the amount of cement slurry adhering to the borehole wall. After the turbulence-blocking plug 6 reaches the bottom of the hole, it is pushed into the pre-drilled 10-15m reserved borehole.

[0076] Step 6: Clean water injection operation. During the clean water injection operation, push the turbulence sealing plug into the grouting borehole through the conversion pipe at the set time intervals. Stop the water injection when the water volume reaches 1.5 to 2.5 times the total volume of the grouting borehole. The clean water injection operation is then completed.

[0077] Step 7: After the grouting material has reached its set time, perform hole cleaning.

[0078] The specific technical features described in the above embodiments can be combined in any suitable manner without contradiction, as long as they do not violate the spirit of the present invention, and should also be regarded as the content disclosed by the present invention.

Claims

1. A drilling high-pressure grouting replacement system, characterized in that, It includes a storage pipe (1), a conversion pipe (2) and a cementing casing (3) arranged coaxially from top to bottom. A first gate valve (4) is provided between the storage pipe (1) and the conversion pipe (2), and a second gate valve (5) is provided between the conversion pipe (2) and the cementing casing (3). The lower end of the cementing casing (3) extends into the grouting borehole. The storage tube (1) is provided with a flow-blocking plug (6), and an annular channel is formed between the outer wall of the flow-blocking plug (6) and the inner wall of the storage tube (1). It also includes a three-way valve (7), the first channel of which can be connected to the grouting pump via the first grouting hose (13), the second channel of which is connected to the upper port of the storage pipe (1) via the second grouting hose (8), and the third channel of which is connected to the grouting interface opened on the conversion pipe (2) via the third grouting hose (9). During grouting operations, cement slurry enters the grouting borehole through the third grouting hose (9), the conversion pipe (2), and the cementing casing (3); When pushing the turbulence-blocking plug (6), the injected fluid enters the storage pipe (1) through the second grouting hose (8), pushes the turbulence-blocking plug (6) into the conversion pipe, and then enters the conversion pipe (2) through the third grouting hose (9), pushing the turbulence-blocking plug (6) into the grouting borehole; The turbulence-blocking plug (6) is made of concrete with added polypropylene fibers. The polypropylene fibers are added at a dosage of 0.5-0.6 kg / m³ based on the volume of the turbulence-blocking plug. The polypropylene fibers are cylindrical or sheet-shaped and have a length of 6 mm to 50 mm. The turbulence-blocking plug (6) includes an integrally connected hemispherical plug head (61) and a cylindrical plug body (62), and the outer surface of the plug body (62) is provided with a plurality of trapezoidal grooves (621) along the circumferential direction. The length of the turbulence-blocking plug (6) is 0.4 to 0.7 meters, and the length of the turbulence-blocking plug (6) is greater than 5.5 times the diameter of the plug body; The depth of the trapezoidal groove (621) is 0.3 to 0.6 times the diameter of the plug body, and the ratio of the length of the lower base of the trapezoidal groove (621) to the depth of the trapezoidal groove (621) is greater than 1.

8. The spacing between adjacent trapezoidal grooves (621) is 0.5 to 1.3 times the diameter of the plug body. The distance between the outer wall of the plug (62) and the inner wall of the storage tube (1) is 5mm~10mm.

2. The drilling high-pressure grouting replacement system as described in claim 1, characterized in that, The second grouting hose (8) is also provided with a third gate valve (10), and the third grouting hose (9) is also provided with a fourth gate valve (11).

3. The drilling high-pressure grouting replacement system as described in claim 1, characterized in that, The conversion pipe (2) has a pressure relief port (21) on its wall and a pressure gauge (12) on its wall.

4. A method for high-pressure grouting displacement in boreholes, characterized in that, The method is implemented using the high-pressure grouting replacement system for boreholes as described in any one of claims 1 to 3, and includes the following steps: Step 1: Complete the drilling of the vertical well section of the grouting borehole. At least one cementing casing is installed in the vertical well section, and the cementing casing extends along the length of the vertical well section, connecting the cementing casing and the transition pipe. Step 2: Determine the diameter of the turbulence-causing plug based on the diameter of the grouting borehole, and complete the prefabrication of the turbulence-causing plug. The diameter of the grouting borehole is 5-10 mm larger than the diameter of the turbulence-causing plug. Step 3: Complete the drilling construction of the grouting section of the grouting borehole, and obtain the water output data in real time during the drilling process. After the water output reaches the design grouting value, continue drilling for 10~15m. Step 4: Complete the connection between the grouting pump, storage pipe, and conversion pipe. Then, flush the hole with clean water at a flow rate of 0.5~0.7m / s until the water injection volume reaches 1.5~2.5 times the total volume of the grouting borehole. Step 5: Perform grouting operation. During the grouting operation, push the turbulence sealing plug through the conversion pipe into the grouting borehole at set time intervals. The grouting operation ends when the grouting time reaches the set value. Step 6: Clean water injection operation. During the clean water injection operation, push the turbulence sealing plug into the grouting borehole through the conversion pipe at the set time intervals. Stop the water injection when the water volume reaches 1.5 to 2.5 times the total volume of the grouting borehole. The clean water injection operation is then completed. Step 7: After the grouting material has reached its set time, perform hole cleaning.

5. The high-pressure grouting displacement method for borehole drilling as described in claim 4, characterized in that, The pushing the turbulence packer into the cementing borehole at a set time interval as described in step 5 specifically includes: when the cement slurry density is 1.2 g / cm 3 , the time interval is 6 hours; when the density is 1.3 g / cm 3 , the time interval is 5.5 hours; when the density is 1.4 g / cm 3 , the time interval is 5 hours; when the density is 1.5 g / cm 3 , the time interval is 4.5 hours.

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