Horizontal drilling reversible anti-sloughing and grouting integrated system and method

Abstract

The application provides a horizontal drilling reversible anti-collapse and grouting integrated system and method, which comprises the following steps: conveying the cementing agent through a first annular channel formed between a rotating drill pipe and a heat insulation layer in a coaxial multi-layer drill pipe assembly, and spraying the cementing agent to the hole wall of a fracture zone through a cementing agent spray port on the side of a drill bit; simultaneously, a cooling medium is circulated in a condenser pipe arranged in a second annular channel, so that a support pipe is kept in a radial contraction state and assists the cementing agent to quickly solidify to form a temporary cementing layer, and temporary hole wall protection is realized; then, the cooling medium is stopped, the support pipe is radially expanded by the temperature of the stratum, the hole wall and the temporary cementing layer are actively supported and tightened, and high-strength mechanical support is provided; after drilling is completed, a grouting mechanism with a grouting head, an electric heating wire and a grouting port is lowered, passes through a grouting hole prearranged on the wall of the support pipe along the inner cavity of the support pipe, the electric heating wire is used to heat and melt the temporary cementing layer to open a grouting channel, and permanent grout is injected; finally, the support pipe is contracted by circulating the cooling medium again, and the support pipe can be recovered.

Description

Technical Field

[0001] This invention relates to the field of drilling engineering and underground engineering support technology, specifically to an integrated system and method for reversible anti-collapse and grouting of horizontal boreholes. Background Technology

[0002] Encountering fault fracture zones is a common technical challenge in underground engineering projects such as tunnel excavation, coal mine roadway development, geological exploration, and horizontal directional drilling. Fault fracture zones typically feature well-developed joints, poor cementation, and weak self-stabilization, making them highly susceptible to collapse, rockfalls, stuck drill bits, and even borehole failure during horizontal drilling, severely restricting drilling efficiency and exploration accuracy.

[0003] To ensure the safe passage of horizontal boreholes through fractured zones, existing technologies mainly employ methods such as casing wall protection, mud wall protection, or pre-grouting reinforcement. However, these methods have significant shortcomings in practical applications:

[0004] The lack of temporary borehole wall support methods during the exploration phase has significant drawbacks. Casing wall support is costly and occupies valuable borehole cross-section; mud wall support is prone to leakage in severely fractured formations and fails to provide effective support; while pre-grouting reinforcement, although reliable, alters the original permeability and mechanical parameters of the formation, leading to distorted exploration data. Furthermore, existing temporary support methods cannot provide active, reversible, and strong support and lack integrated connection with subsequent permanent grouting, often requiring secondary drilling or chemical dissolution to remove the temporary layer, which is complex and easily damages the already stabilized borehole wall.

[0005] In view of this, the inventor has specifically designed a horizontal drilling reversible anti-collapse and grouting integrated system and method, which leads to this invention. Summary of the Invention

[0006] To solve the above problems, the technical solution of the present invention is as follows: A horizontal borehole reversible anti-collapse and grouting integrated system includes a drill bit and a grouting mechanism, and further includes: The multi-layer drill pipe assembly is coaxially nested in multiple layers, and the multi-layer drill pipe assembly includes components arranged sequentially from the inside out. The rotary drill pipe comprises a rotary drill rod, a heat insulation layer, and an outermost support pipe; wherein the rotary drill rod is hollow inside and forms a first annular channel for conveying a binder between itself and the heat insulation layer; a second annular channel is formed between the heat insulation layer and the support pipe, and a condenser pipe for circulating a low-temperature medium is provided in the second annular channel; multiple pre-set grouting holes are opened on the wall of the support pipe; a drill bit is provided at the end of the rotary drill rod, and a drilling fluid nozzle communicating with the interior of the rotary drill rod is provided at one end of the drill bit facing the drilling direction, and a binder nozzle communicating with the first annular channel is provided on its outer peripheral wall; The grouting mechanism includes a delivery hose and a grouting head disposed at the end of the delivery hose. The grouting head is provided with a heating wire and a grouting port. The diameter of the grouting port matches the grouting hole on the support pipe. The grouting mechanism is used to be lowered into the support pipe after drilling is completed. The grouting head passes through the grouting hole of the support pipe and heats and melts the temporary cementing layer before injecting permanent grout. The cooling medium circulation unit, connected to the condenser pipe, is used to supply or discharge cooling medium to the condenser pipe so that the support pipe contracts radially or expands radially under the influence of ground temperature.

[0007] Preferably, the support tube is made of a thermal expansion alloy, and the radial shrinkage rate of the support tube is greater than 1.5%.

[0008] Preferably, the grouting holes on the support pipe wall are arranged in an array and the hole diameter is 10 mm to 20 mm.

[0009] Preferably, the grouting head is also fitted with an expanding rubber sealing ring, which is used to seal the annular space gap between the grouting hole and the grouting mechanism during grouting.

[0010] Preferably, the grouting head is located at the head of the grouting mechanism, and the grouting head is also equipped with a deflection mechanism linked to the ground control system and an in-hole camera.

[0011] Preferably, the cooling medium is liquid nitrogen or an aqueous solution of ethylene glycol pre-cooled to -10°C to -5°C.

[0012] This invention also provides a method for using a horizontal borehole reversible anti-collapse and grouting integrated system, comprising the following steps: In the early stage of the drill bit entering the fracture zone, a cooling medium is injected into the condenser tube to continuously cool down the tube and keep the support tube in a radially contracted state. As the drill bit continues to advance, the binder is delivered through the first annular channel and released into the fracture zone around the borehole wall through the binder nozzle. The low temperature environment allows the resin to solidify rapidly and form a temporary binder layer. When the drill bit stops drilling into the fractured zone to a preset distance, the cooling medium is discharged, and the support pipe is radially expanded by the formation temperature, which tightly supports the borehole wall and the temporary cementing layer to form an active mechanical support. After drilling is completed and the fracture zone is temporarily supported by the support pipe, the rotary drill rod, heat insulation layer and drill bit are taken out from the borehole and lowered into the grouting mechanism. The grouting head is used to align the grouting port with the grouting hole, and the head of the grouting mechanism is pushed through the grouting hole and close to the temporary cementing layer. The electric heating wire is started to heat to the melting temperature of the cementing agent, so that the temporary cementing layer melts locally and opens the grouting channel. Then, permanent grout is injected under high pressure to achieve reinforcement. After the grouting is completed and solidified, a low-temperature medium is injected into the condenser tube again, causing the support tube to shrink radially and detach from the borehole wall, and the support tube is then recovered.

[0013] Preferably, the heating temperature of the heating wire is 200℃~300℃, and the heating time is 30 seconds~120 seconds.

[0014] The technical solution provided by this invention has the following beneficial effects: This invention delivers binder through a first annular channel formed between the rotating drill rod and the insulation layer in a coaxial multi-layer drill rod assembly. The binder is then sprayed onto the borehole wall of the fractured zone via binder nozzles on the side of the drill bit. Simultaneously, a condenser tube installed in the second annular channel circulates cooling medium, keeping the support tube in a radially contracted state and assisting the binder in rapidly solidifying to form a temporary binder layer, achieving immediate temporary wall protection. Subsequently, the cooling medium is stopped, and the support tube, made of thermal expansion alloy, expands radially due to the formation temperature, actively tightening the borehole wall and the temporary binder layer, providing high-strength mechanical support. After drilling is completed, a grouting mechanism equipped with a grouting head, heating wire, and grouting port is lowered. The grouting mechanism passes through a pre-set grouting hole on the tube wall along the inner cavity of the support tube. The heating wire heats and melts the temporary binder layer to open the grouting channel, allowing permanent grout to be injected. Finally, cooling medium is introduced again to contract the support tube, enabling its recovery. In this invention, the temporary cementing layer and the expansion support pipe work together, enabling safe drilling without permanent grouting during the exploration phase. Furthermore, the temporary layer and the grouting are seamlessly connected through electrothermal melting in the later stage, avoiding secondary damage to the borehole wall. The support pipe can be shrunk and recycled at low temperatures, reducing material costs. At the same time, it does not change the original permeability and mechanical parameters of the formation, meeting the requirements for the authenticity of exploration data. Attached Figure Description

[0015] The accompanying drawings, which are provided to further illustrate the invention and constitute a part of this invention, are illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention.

[0016] in: Figure 1 This is a schematic diagram of formation drilling in this invention; Figure 2 This is a schematic diagram of the internal space of the drill bit and rotating drill rod in this invention; Figure 3 This is a schematic diagram of the support tube structure in this invention; Figure 4 This is a schematic diagram of the grouting mechanism in this invention.

[0017] Label Explanation: In the diagram: 1. Fracturing zone; 2. Temporary cementing layer; 3. Rotary drill pipe; 4. Insulation layer; 5. Support pipe; 51. Grouting hole; 6. First annular channel; 7. Second annular channel; 71. Condenser pipe; 8. Drill bit; 81. Drilling fluid nozzle; 82. Cementitious agent nozzle; 9. Grouting mechanism; 91. Grouting head; 92. Delivery hose; 93. Heating wire; 94. Grouting port; 95. Expanded rubber sealing ring. Detailed Implementation

[0018] To make the technical problems, solutions, and beneficial effects of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the invention.

[0019] Please see Figures 1-4 This is a horizontal drilling reversible anti-collapse and grouting integrated system, which is a preferred embodiment of the present invention, comprising: The multi-layer drill pipe assembly is coaxially nested in multiple layers, and the multi-layer drill pipe assembly includes components arranged sequentially from the inside out. The system comprises a rotary drill pipe 3, a heat insulation layer 4, and an outermost support pipe 5. The rotary drill pipe 3 is used for conveying drilling fluid, and the heat insulation layer 4 is made of heat-insulating ceramic, whose core function is to isolate internal and external heat transfer and ensure the smooth ejection of the binder. The rotary drill pipe 3 is hollow inside and forms a first annular channel 6 between itself and the heat insulation layer 4 for conveying the binder. In this embodiment, the first annular channel 6 conveys thermosetting epoxy low-temperature thixotropic resin. This material maintains good fluidity at high temperatures and solidifies rapidly when the temperature decreases, binding the rocks in the fracture zone 1 together and forming a temporary support structure on the surface of the fracture zone 1. A second annular channel 7 is formed between the heat insulation layer 4 and the support pipe 5. The second annular channel 7 is provided with a condenser pipe 71 for circulating low-temperature medium. The support pipe 5 has multiple preset grouting holes 51 on its wall. In this embodiment, the cooling medium in the condenser pipe 71 is circulating liquid nitrogen. During the liquid nitrogen circulation, the condenser pipe 71 causes the support pipe 5 to contract, making the outer diameter of the support pipe 5 significantly smaller than the borehole diameter, which facilitates low-resistance advancement in the complex fracture zone 1. High temperature state (after liquid nitrogen injection stops): After the liquid nitrogen injection stops and is discharged, the alloy pipe undergoes significant thermal expansion under the action of ground temperature. After expansion, the pipe body tightly supports the borehole wall, forming a strong mechanical support skeleton.

[0020] The drill bit 8 is located at the front end of the rotary drill rod 3. Its front side is provided with a drilling fluid nozzle 81 that communicates with the rotary drill rod 3 for spraying drilling fluid, and its side side is provided with a binder nozzle 82 that communicates with the first annular channel 6. A cooling medium circulation unit, connected to the condenser coil 71, is used to selectively supply or discharge cooling medium to the condenser coil 71, so as to... The support pipe 5 may contract radially or expand radially under the influence of ground temperature. The grouting mechanism 9 includes a delivery hose 92 and a grouting head 91 disposed at the end of the delivery hose 92. The grouting head 91 is provided with a heating wire 93 and a grouting port 94. The diameter of the grouting port 94 matches the grouting hole 51 on the support pipe 5. The grouting mechanism 9 is used to be lowered into the support pipe 5 after drilling is completed. The grouting head 91 passes through the grouting hole 51 of the support pipe 5 and heats and melts the temporary cementing layer 2 before injecting permanent grout.

[0021] Please see Figures 1-4 The support tube 5 is made of a high-performance thermal expansion alloy. The radial shrinkage rate of the support tube 5 is greater than 1.5%. When the cooling medium circulation unit injects low-temperature medium into the condenser tube 71, the radial shrinkage rate of the support tube 5 exceeds 1.5%, making its outer diameter significantly smaller than the borehole diameter, thereby achieving low-resistance advancement during drilling and avoiding scratching the borehole wall. When the cooling medium is stopped and discharged, the support tube 5 expands radially under the action of ground temperature, tightly supporting the borehole wall and providing active support. When the permanent grouting reinforcement is completed and the support tube 5 needs to be recovered, the low-temperature medium is injected again, and the support tube 5 regains a radial shrinkage of greater than 1.5%, detaching from the borehole wall and thus being successfully recovered. In this embodiment, the support tube 5 is made of Ni-Ti-based shape memory alloy or Fe-Mn-Si-based shape memory alloy. This type of alloy, while remaining in an austenitic state at liquid nitrogen temperatures, can radially shrink (with a shrinkage rate of 4%–8%). After being lowered into the borehole, it undergoes a martensitic inverse transformation as the formation temperature rises (typically 15℃–30℃), returning to its pre-set expanded state with a radial expansion rate greater than 1.5%, thus tightly supporting the borehole wall. Simultaneously, this type of alloy can re-shrink after re-injection of liquid nitrogen, facilitating the recovery of the support tube 5. The radial shrinkage rate of the support tube 5 is controlled through alloy composition design, heat treatment processes, and dimensional differences in its pre-set shape, ensuring a shrinkage rate greater than 1.5%.

[0022] Please see Figures 1-4 The grouting holes 51 on the wall of the support pipe 5 are arranged in an array and have a diameter of 15 mm. The 15 mm diameter ensures that the head of the grouting mechanism 9 can pass through smoothly and is also large enough to accommodate the heating wire 93 to heat and melt the temporary cementing layer 2 to form a smooth grouting channel. At the same time, it avoids the grout backflow or the temporary cementing layer 2 not being sealed properly due to the hole diameter being too large.

[0023] Please see Figures 1-4The grouting head 91 is also fitted with an expanding rubber sealing ring 95, which is used to seal the annular gap between the grouting hole 51 and the grouting mechanism 9 during grouting. When the grouting head 91 of the grouting mechanism 9 passes through the grouting hole 51 on the support pipe 5, the grouting pump is started to inject permanent grout. At the same time, the grout pressure acts on the expanding rubber sealing ring 95, causing it to expand radially and fit tightly against the inner wall of the grouting hole 51, forming a reliable dynamic seal. The sealing ring expands automatically under the grouting pressure. The greater the pressure, the better the sealing effect, effectively preventing the grout from flowing back out of the annular gap between the grouting mechanism 9 and the grouting hole 51, ensuring that all the grout enters the rock fractures in the fracture zone 1. After grouting is completed, grouting is stopped and the pressure is released. The expanding rubber sealing ring 95 returns to its original shape, making it easy for the grouting mechanism 9 to smoothly exit from the grouting hole 51.

[0024] Please see Figures 1-4 The grouting head 91 is located at the head of the grouting mechanism 9. The grouting head 91 is also equipped with a deflection mechanism linked to the ground control system and an in-hole camera. The in-hole camera captures real-time images of the front and surrounding areas of the grouting mechanism 9 and transmits the image signals to the ground control system. The operator observes the position and orientation of the grouting hole 51 on the support pipe 5 through a screen. Based on the image information, the ground control system issues a command to drive the deflection mechanism to precisely adjust the orientation angle of the head of the grouting mechanism 9, ensuring accurate alignment of the grouting port 94 and the grouting hole 51 in three-dimensional space. The deflection mechanism can employ a universal joint driven by a micro-motor or a hydraulic micro-push rod to achieve precise deflection at small angles.

[0025] Please see Figures 1-4 The cooling medium is liquid nitrogen or an ethylene glycol aqueous solution pre-cooled to -10℃ to -5℃. When the strata being traversed have high strength and strict requirements on the contraction speed and amount of the support pipe 5, liquid nitrogen is selected as the cooling medium. Its boiling point is extremely low (-196℃), which can quickly cool the support pipe 5 to the required temperature, achieving a radial contraction of more than 1.5%, ensuring low-resistance advancement in the hard and fractured zone 1. When the strata being traversed have low strength and hardness and the requirements for cooling speed are not high, an ethylene glycol aqueous solution pre-cooled to -10℃ to -5℃ can be used as an alternative cooling medium. Ethylene glycol aqueous solution has a low freezing point and good fluidity. Through circulation through the condenser pipe 71, the support pipe 5 can also generate sufficient radial contraction to meet drilling requirements.

[0026] This invention also provides a method for using a horizontal drilling reversible anti-collapse and grouting integrated system, characterized by the following steps: In the early stage of the drill bit 8 entering the fracture zone 1, a cooling medium is injected into the condenser tube 71 to continuously cool down the temperature, so that the support tube 5 remains in a radially contracted state. As the drill bit 8 continues to advance, the binder is transported through the first annular channel 6 and released into the fracture zone 1 around the borehole wall through the binder nozzle 82. The low temperature environment allows the resin to solidify rapidly to form a temporary binder layer 2. When drilling into the fractured zone 1 to 1m (the limit span of the temporary support, related to the properties of the binder), drill bit 8 stops, the cooling medium is discharged, and the support pipe 5 is radially expanded using the formation temperature. After 3-5 minutes, the support pipe 5 reaches the designed expansion amount, and the pipe body undergoes significant radial thermal expansion, strongly compressing the borehole wall and together with its temporary support structure to form a comprehensive support body supported by a high-strength metal skeleton and high viscosity. This state provides strong temporary support and effective closure to the fractured zone 1, ensuring borehole stability and controllable pipe diameter expansion to achieve a high-pressure support state. Repeat the above steps until the fractured zone 1 is passed;

[0027] After drilling is completed and temporary support is provided for the fractured zone 1 through the support pipe 5, the rotary drill rod 3, the heat insulation layer 4, and the drill bit 8 are removed from the borehole and lowered into the grouting mechanism 9. After the grouting mechanism 9 is lowered to the depth of the support pipe 5, the relative position of the grouting mechanism 9 and the borehole of the support pipe 5 is confirmed by using an in-hole camera. The grouting head 91 is used to align the grouting port 94 with the grouting hole 51. The in-hole camera on the grouting head 91 starts working, capturing real-time images of the inner wall of the support pipe and transmitting them back to the ground. The operator observes the position of the grouting holes 51 on the wall of the support pipe 5 via a screen. Because the grouting holes 51 are distributed in an array pattern on the wall of the support pipe 5, the camera device can clearly identify their outlines. The ground control system determines the relative orientation of the grouting head 91 with the nearest grouting hole 51 based on the image. If the grouting port 94 of the grouting head 91 is not aligned with the grouting hole 51, the deflection mechanism (micro-motor or hydraulic push rod) on the grouting head is driven by ground commands to fine-tune the orientation angle of the grouting head 91 until the grouting port 94 and the grouting hole 51 are aligned in both the axial and radial directions. After confirming alignment, the ground operator continues to push the grouting hose 92 forward. The outer diameter of the grouting head 91 is slightly smaller than the diameter of the grouting hole 51 (the two diameters match). Under the action of the pushing force, the grouting head 91 passes through the grouting hole 51 on the pipe wall from the inner cavity of the support pipe 5 to the outside of the support pipe 5. The head of the grouting mechanism 9 is pushed through the grouting hole 51 and closely adheres to the temporary cementing layer 2. The heating wire 93 is activated to heat to the melting temperature of the cementitious agent, causing the temporary cementing layer 2 to partially melt and open the grouting channel. Then, permanent grout is injected under high pressure to achieve permanent reinforcement. The head of the grouting mechanism 9 is equipped with an expansion rubber ring seal to ensure that the grout does not flow back from the hole into the annulus during grouting. The position and temperature of the grouting mechanism 9 are maintained, and cement-based or chemical grout is injected under high pressure into the fractured zone 1 through the hose. Under pressure, the grout seeps into the gaps of the fractured rock mass to achieve permanent reinforcement. After grouting is completed, heating is stopped, and the grouting mechanism 9 is retracted after a short period of initial setting. The hole on the support pipe 5 is resealed due to the melting of the temporary cementing layer 2, which does not affect the integrity of the support structure.

[0028] After the permanent grouting is completed and solidified, a low-temperature medium is injected into the condenser tube 71 again, causing the support tube 5 to contract radially and detach from the hole wall, and the support tube 5 is then recovered.

[0029] Please see Figures 1-4 The heating wire 93 has a heating temperature of 300℃ and a heating time of 50 seconds. When the grouting head 91 of the grouting mechanism 9 passes through the grouting hole 51 of the support pipe 5 and is in close contact with the temporary cementing layer 2, the heating wire 93 is activated. Within the temperature range of 300℃, the thermosetting epoxy low-temperature thixotropic resin temporary cementing layer 2 softens and melts rapidly, forming a smooth grouting channel. At the same time, the heating time of 50 seconds is sufficient to ensure that the local cementing layer is completely melted, while avoiding excessive heat conduction to the support pipe 5 and the surrounding rock mass, preventing the support pipe 5 from undergoing irreversible deformation or the rock mass from thermally cracking due to overheating.

[0030] In summary, this invention delivers the binder through the first annular channel 6 formed between the rotating drill rod 3 and the heat insulation layer 4 in the coaxial multi-layer drill rod assembly. The binder is sprayed onto the borehole wall of the fracture zone 1 through the binder nozzle 82 on the side of the drill bit 8. Simultaneously, the cooling medium is circulated through the condenser pipe 71 set in the second annular channel 7, keeping the support pipe 5 in a radially contracted state and assisting the binder to quickly solidify and form a temporary binder layer 2, achieving immediate temporary wall protection. Subsequently, the cooling medium is stopped, and the support pipe 5, made of thermal expansion alloy, expands radially by relying on the formation temperature, actively tightening the borehole wall and the temporary binder layer 2, providing high-strength mechanical support. After drilling is completed, the grouting mechanism 9, equipped with a grouting head 91, an electric heating wire 93, and a grouting port 94, is lowered. It passes through the pre-set grouting hole 51 on the pipe wall along the inner cavity of the support pipe 5. The electric heating wire 93 heats and melts the temporary binder layer 2 to open the grouting channel and inject permanent grout. Finally, the cooling medium is circulated again to contract the support pipe 5, allowing the support pipe 5 to be recovered. In this invention, the temporary cementing layer 2 and the expansion support pipe 5 work together to enable safe drilling without permanent grouting during the exploration stage. Furthermore, the temporary layer and the grouting are seamlessly connected through electrothermal melting in the later stage, avoiding secondary damage to the borehole wall. The support pipe 5 can be shrunk and recycled at low temperatures, reducing material costs. At the same time, it does not change the original permeability and mechanical parameters of the formation, meeting the requirements for the authenticity of exploration data.

[0031] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution of the present invention, or the direct application of the inventive concept and technical solution of the present invention to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A horizontal borehole reversible anti-collapse and grouting integrated system, characterized in that, include: A multi-layer drill pipe assembly is coaxially nested in multiple layers. The assembly includes, from the inside out, a rotary drill pipe, a heat insulation layer, and an outermost support pipe. The rotary drill pipe is hollow and forms a first annular channel with the heat insulation layer for conveying a binder. A second annular channel is formed between the heat insulation layer and the support pipe, and a condenser pipe for circulating a low-temperature medium is provided within the second annular channel. The support pipe has multiple pre-set grouting holes on its wall. The rotary drill pipe has a drill bit at one end, with a drilling fluid nozzle communicating with the interior of the rotary drill pipe at one end facing the drilling direction, and a binder nozzle communicating with the first annular channel on its outer peripheral wall. The grouting mechanism includes a delivery hose and a grouting head disposed at the end of the delivery hose. The grouting head is provided with a heating wire and a grouting port. The diameter of the grouting port matches the grouting hole on the support pipe. The grouting mechanism is used to be lowered into the support pipe after drilling is completed. The grouting head passes through the grouting hole of the support pipe and heats and melts the temporary cementing layer before injecting permanent grout. The cooling medium circulation unit, connected to the condenser pipe, is used to supply or discharge cooling medium to the condenser pipe so that the support pipe contracts radially or expands radially under the influence of ground temperature.

2. The horizontal drilling reversible anti-collapse and grouting integrated system according to claim 1, characterized in that, The support tube is made of a thermal expansion alloy, and the radial shrinkage rate of the support tube is greater than 1.5%.

3. The horizontal drilling reversible anti-collapse and grouting integrated system according to claim 1, characterized in that, The grouting holes on the support pipe wall are arranged in an array with a diameter of 10 mm to 20 mm.

4. The horizontal drilling reversible anti-collapse and grouting integrated system according to claim 1, characterized in that, The grouting head is also fitted with an expansion rubber sealing ring, which is used to seal the annular space gap between the grouting hole and the grouting mechanism during grouting.

5. The horizontal drilling reversible anti-collapse and grouting integrated system according to claim 1, characterized in that, The grouting head is located at the head of the grouting mechanism. The grouting head is also equipped with a deflection mechanism that is linked to the ground control system and an in-hole camera.

6. The horizontal drilling reversible anti-collapse and grouting integrated system according to claim 1, characterized in that, The cooling medium is liquid nitrogen or an aqueous solution of ethylene glycol pre-cooled to -10°C to -5°C.

7. A method of using the horizontal borehole reversible anti-collapse and grouting integrated system as described in any one of claims 1-6, characterized in that, Includes the following steps: In the early stage of the drill bit entering the fracture zone, a cooling medium is injected into the condenser tube to continuously cool down the tube and keep the support tube in a radially contracted state. As the drill bit continues to advance, the binder is delivered through the first annular channel and released into the fracture zone around the borehole wall through the binder nozzle. The low temperature environment allows the resin to solidify rapidly and form a temporary binder layer. When the drill bit stops drilling into the fractured zone to a preset distance, the cooling medium is discharged, and the support pipe is radially expanded by the formation temperature, which tightly supports the borehole wall and the temporary cementing layer to form an active mechanical support. After drilling is completed and the fracture zone is temporarily supported by the support pipe, the rotary drill rod, heat insulation layer and drill bit are taken out from the borehole and lowered into the grouting mechanism. The grouting head is used to align the grouting port with the grouting hole, and the head of the grouting mechanism is pushed through the grouting hole and close to the temporary cementing layer. The electric heating wire is started to heat to the melting temperature of the cementing agent, so that the temporary cementing layer melts locally and opens the grouting channel. Then, permanent grout is injected under high pressure to achieve reinforcement. After the permanent grouting is completed and solidified, a low-temperature medium is injected into the condenser tube again, causing the support tube to shrink radially and detach from the borehole wall, and the support tube is then recovered.

8. The method of using the horizontal drilling reversible anti-collapse and grouting integrated system according to claim 7, characterized in that, The heating temperature of the heating wire is 200℃~300℃, and the heating time is 30 seconds~120 seconds.

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