Anti-drag thixotropic slurry construction method

Abstract

The invention provides an anti-drag thixotropic slurry construction method, which relates to the field of pipe jacking and comprises the following steps: step 1, excavating a starting well, arranging jacking equipment, a slurry storage box and a pump body in the starting well, filling the slurry storage box with anti-drag thixotropic slurry, connecting the pump body with the slurry storage box, and arranging hoisting equipment on the ground; secondly, all the jacking pipes to be installed are transported to the ground near the starting well; a ring pipe is fixedly connected to the inner wall of the top pipe, a first slurry pipe and a second slurry pipe are fixedly connected to the ring pipe, four or more three-way pipes are fixedly connected to the ring pipe, branch pipes are fixedly connected to the three-way pipes, a support and an installation base are fixedly connected to the inner wall of the top pipe, a stirring box is connected to the support, the stirring box is connected with the second slurry pipe and the third slurry pipe, and a box cavity is formed in the stirring box. A rotating rod is rotationally connected to the inner wall of the box cavity, two or more stirring blades are fixedly connected to the rotating rod, and the lower end of the rotating rod extends to the position below the stirring box and is fixedly connected with a first transmission wheel. The stirring blades are used for stirring the anti-drag thixotropic slurry to enhance the fluidity of the anti-drag thixotropic slurry.

Description

Technical Field

[0001] This invention relates to the field of pipe jacking technology, specifically to a drag-reducing thixotropic mud construction method. Background Technology

[0002] With the continuous development of tunnel construction, underground engineering, and foundation reinforcement, drag-reducing thixotropic drilling mud, due to its excellent drag-reducing properties and controllable thixotropic characteristics, is widely used for lubrication of pipe jacking during pipe jacking construction. This type of mud has high viscosity in a static state, which can prevent material diffusion and loss, while under shearing or agitation conditions, the viscosity rapidly decreases, making it easy to inject into pores or gaps. It is currently a widely used engineering drilling mud material.

[0003] However, in actual grouting processes, especially under long-distance or high-resistance conditions, drag-reducing thixotropic grout still faces certain fluidity issues. Specifically, when flowing in the grouting pipe, the grout rapidly recovers its high viscosity due to the confined space and local cooling effect, leading to increased flow resistance. This may result in uneven grouting, incomplete filling, and affect the lubrication effect of the jacking pipe. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention aims to provide a drag-reducing thixotropic mud construction method. To solve these problems, this invention employs the following technical solution: A drag-reducing thixotropic mud construction method includes the following steps: Step 1: Excavate the starting shaft, and arrange the jacking equipment, slurry storage tank and pump body in the starting shaft. The slurry storage tank is filled with drag-reducing thixotropic mud. The pump body and the slurry storage tank are connected. Lifting equipment is arranged on the ground. Step 2: Transport all the pipe jacking sections to be installed to the ground near the starting shaft; A ring pipe is fixed to the inner wall of the jacking pipe. A slurry pipe 1 and a slurry pipe 2 are fixed to the ring pipe. A valve 1 is installed on the slurry pipe 1. Four or more tee pipes are fixed to the ring pipe. A branch pipe is fixed to the tee pipe. A valve 2 is installed on the branch pipe. One end of the branch pipe extends to the outer wall of the jacking pipe. A support and a mounting base are fixed to the inner wall of the jacking pipe. A mixing box is connected to the support. The mixing box is connected to slurry pipe 2 and slurry pipe 3. A box cavity is opened on the mixing box. A rotating rod is rotatably connected to the inner wall of the box cavity. Two or more mixing blades are fixed to the rotating rod. The lower end of the rotating rod extends to the bottom of the mixing box. A transmission wheel 1 is fixed to the lower end of the rotating rod. A transmission wheel 2 is fixed to the bottom wall of the transmission wheel 1. An automatic transmission belt connection mechanism is connected to the inner wall of the jacking pipe. A transmission belt 2 is connected between the transmission wheel 2 and the automatic transmission belt connection mechanism. A transmission wheel 3 is rotatably connected to the bottom wall of the mounting base. A transmission wheel 4 is fixed to the bottom wall of the transmission wheel 3. The transmission wheel 3 is connected to the transmission wheel 1 through a transmission belt 1. Step 3: Install the first jacking pipe: Install the motor on the mounting base of the first jacking pipe, and connect the motor rotor and the transmission wheel. Step 4: Use hoisting equipment to lift the first jacking pipe into the starting shaft, start the jacking equipment to push the first jacking pipe into the inner wall of the starting shaft, connect the slurry pipe three and the pump body, close valve one, open all valve two, turn on the pump body and motor, so that the drag-reducing thixotropic mud is sprayed from each branch pipe to the outer wall of the jacking pipe for lubrication. When the drag-reducing thixotropic mud passes through the box cavity, the motor rotor indirectly drives the stirring blade to rotate. The stirring blade stirs the drag-reducing thixotropic mud to enhance its fluidity. Step 5: After grouting is paused, the pump body and motor stop working, disconnect the pump body and grout pipe three, and use the hoisting equipment to lift the second jacking pipe into the starting well. During this process, the automatic transmission belt connection mechanism will automatically connect the transmission belt two inside the first jacking pipe to the transmission wheel four of the second jacking pipe. Start the jacking equipment to push the second jacking pipe into the inner wall of the starting well. Step 6: Connect the grout pipe 3 on the first jacking pipe and the grout pipe 1 on the second jacking pipe. Connect the pump body to the grout pipe 3 on the second jacking pipe. Open valve 1 and all valves 2 on the second jacking pipe to perform grouting. The motor drives the two rotating rods to rotate, thereby agitating the drag-reducing thixotropic mud as it flows through the two chambers to enhance its fluidity. Step 7: Referring to Steps 5 and 6, proceed with the subsequent pipe jacking and grouting operations.

[0005] Preferably, the mixing tank is slidably connected to the support, the mixing tank is connected to the support through an elastic element, a slide is slidably connected to the support, a tensioning wheel is rotatably connected to the slide, the slide is connected to the support through an elastic element, and the tensioning wheel abuts against the transmission belt. The automatic transmission belt connection mechanism includes a first cylinder and a second cylinder. The first cylinder is fixed to the support and has a first cylinder cavity. A piston assembly is slidably connected to the inner wall of the first cylinder cavity, extending to the outside of the first cylinder. Two spreading wheel assemblies are fixed to the first cylinder, which spread the second transmission belt. A seat cavity is provided on the support, and the second cylinder is fixed to the seat cavity. The second cylinder has a second cylinder cavity, the inner wall of which is connected to the inner wall of the first cylinder cavity via an air pipe. A piston assembly is slidably connected to the inner wall of the second cylinder cavity, extending to the outside of the second cylinder. A wedge block is fixed to the second piston assembly, connected to the outer wall of the second cylinder via an elastic element, extending to the outside of the seat cavity. A frustum is fixed to the bottom wall of the fourth transmission wheel.

[0006] Preferably, a permanent magnet is embedded in the mounting base, and a permanent magnet, a slide bar, a slide plate, and an insert bar are slidably connected to the inner wall of the base cavity. The permanent magnet is fixed to the slide bar and connected to the inner wall of the base cavity through an elastic element. A push bar is rotatably connected to the slide bar, and an inclined channel is opened on the slide plate. The push bar is slidably connected to the inner wall of the inclined channel, and the insert bar is fixed to the slide plate. A groove is opened on the top wall of the mixing tank, and a toothed assembly is fixedly connected in the groove.

[0007] Preferably, the front-to-back width of the second cylindrical cavity is greater than the front-to-back width of the first cylindrical cavity.

[0008] Preferably, the slurry storage tank is equipped with a stirring device.

[0009] Preferably, a pressure sensor is provided on the branch pipe, and the pressure sensor monitors the ejection pressure of the drag-reducing thixotropic mud in real time.

[0010] Preferably, both permanent magnet one and permanent magnet two are made of neodymium, iron and boron.

[0011] Preferably, the drag-reducing thixotropic mud material includes starch-based modifiers and vegetable oil emulsions.

[0012] Preferably, the inner diameter of the first slurry pipe, the second slurry pipe, and the third slurry pipe is 30-50 mm.

[0013] Preferably, the spacing between any two adjacent tee pipes on the ring pipe is equal.

[0014] The present invention has the following beneficial effects: The drag-reducing thixotropic mud is sprayed from each branch pipe onto the outer wall of the jacking pipe for lubrication, which significantly reduces the propulsion resistance. When the drag-reducing thixotropic mud passes through the box cavity, the motor rotor indirectly drives the stirring blades to rotate. The stirring blades stir the drag-reducing thixotropic mud to enhance its fluidity, ensuring that the drag-reducing thixotropic mud undergoes sufficient shearing and stirring before injection, further improving its thixotropic properties and fluidity. Attached Figure Description

[0015] The present invention will be further described with reference to the accompanying drawings, but the embodiments in the drawings do not constitute any limitation on the present invention. For those skilled in the art, other drawings can be obtained based on the following drawings without creative effort.

[0016] Figure 1 This is a schematic diagram of the pipe jacking structure in a drag-reducing thixotropic mud construction method of the present invention; Figure 2 This is a structural schematic diagram of the second pipe jacking process in a drag-reducing thixotropic mud construction method of the present invention; Figure 3 This is the present invention. Figure 2 Enlarged view of point A in the middle; Figure 4 This is the present invention. Figure 3 Enlarged view of point B in the middle; Figure 5 This is the present invention. Figure 3 Enlarged view of the mixing tank; Figure 6 This is the present invention. Figure 3 Top view of the second transmission belt; Figure 7 This is the present invention. Figure 3 Top view of the central drive belt; Figure 8 This is the present invention. Figure 3 Top view of the middle slide block; Figure 9 This is the present invention. Figure 3 Schematic diagram of the structure of the fourth transmission wheel; Figure 10 This is the present invention. Figure 3 A schematic diagram of the structure of the first and second transmission wheels.

[0017] Attached reference numerals: 1. Jacking pipe; 2. Ring pipe; 3. T-pipe; 4. Branch pipe; 5. Slurry pipe one; 6. Slurry pipe two; 7. Slurry pipe three; 8. Mixing box; 9. Support; 10. Rotating rod; 11. Mixing blade; 12. Box cavity; 13. Gear assembly; 14. Elastic element one; 15. Transmission wheel one; 16. Transmission wheel two; 17. Transmission belt one; 18. Tensioning wheel; 19. Slide seat; 20. Cylinder one; 21. Cylinder cavity one; 22. Piston assembly one; 23. Spreading wheel assembly; 24. Air tube; 25. Seat cavity; 26. Mounting base; 27. Permanent magnet one; 28. Transmission wheel three; 29. ​​Transmission wheel four; 30. Frustum component; 31. Motor; 32. Cylinder two; 33. Piston assembly two; 34. Wedge block; 35. Elastic component two; 36. Cylinder cavity two; 37. Permanent magnet two; 38. Elastic component three; 39. Sliding bar; 40. Push bar; 41. Sliding plate; 42. Inclined channel; 43. Insert bar; 44. Elastic component four; 45. Transmission belt two. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] In the description of this invention, it should be noted that the terms "vertical," "upper," "lower," and "horizontal," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing the invention and for 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. Therefore, they should not be construed as limitations on the invention. Furthermore, "first," "second," "third," and "fourth" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0020] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "set," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or a connection through an intermediate medium; and they can refer to the internal communication 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.

[0021] like Figures 1-10 As shown, a drag-reducing thixotropic mud construction method includes the following steps: Step 1: Excavate the starting shaft, and arrange the jacking equipment, slurry storage tank and pump body in the starting shaft. The slurry storage tank is filled with drag-reducing thixotropic mud. The pump body and the slurry storage tank are connected. Lifting equipment is arranged on the ground. Step 2: Transport all the pipe jacking sections 1 to be installed to the ground near the starting shaft; A ring pipe 2 is fixedly connected to the inner wall of the jacking pipe 1. A grout pipe 1 (5) and a grout pipe 2 (6) are fixedly connected to the ring pipe 2. A valve 1 is installed on the grout pipe 1 (5). Four or more tee pipes 3 are fixedly connected to the ring pipe 2. A branch pipe 4 is fixedly connected to the tee pipe 3. A valve 2 is installed on the branch pipe 4. One end of the branch pipe 4 extends to the outer wall of the jacking pipe 1. A support 9 and a mounting base 26 are fixedly connected to the inner wall of the jacking pipe 1. A mixing box 8 is connected to the support 9. The mixing box 8 is connected to the grout pipe 2 (6) and the grout pipe 3 (7). A cavity 12 is opened in the mixing box 8. A rotating rod 10 is rotatably connected to the inner wall of the cavity 12. The rotating rod 10... Two or more stirring blades 11 are fixedly attached to the top of the 0. The lower end of the rotating rod 10 extends to the bottom of the mixing tank 8. A transmission wheel 15 is fixedly attached to the lower end of the rotating rod 10. A transmission wheel 26 is fixedly attached to the bottom wall of the transmission wheel 15. An automatic transmission belt connection mechanism is connected to the inner wall of the top pipe 1. A transmission belt 25 is connected between the transmission wheel 26 and the automatic transmission belt connection mechanism. A transmission wheel 3 28 is rotatably connected to the bottom wall of the mounting base 26. A transmission wheel 4 29 is fixedly attached to the bottom wall of the transmission wheel 3 28. The transmission wheel 3 28 is connected to the transmission wheel 15 through a transmission belt 17. Step 3: Install the first jacking pipe 1: Install the motor 31 on the mounting base 26 of the first jacking pipe 1, and connect the rotor of the motor 31 to the transmission wheel 28. Step 4: Use hoisting equipment to hoist the first jacking pipe 1 into the starting shaft, start the jacking equipment to push the first jacking pipe 1 into the inner wall of the starting shaft, connect the slurry pipe 3 7 and the pump body, close valve 1, open all valves 2, turn on the pump body and motor 31, so that the drag-reducing thixotropic mud is sprayed from each branch pipe 4 to the outer wall of the jacking pipe 1 for lubrication, which significantly reduces the propulsion resistance. When the drag-reducing thixotropic mud passes through the box cavity 12, the rotor of motor 31 indirectly drives the stirring blade 11 to rotate. The stirring blade 11 stirs the drag-reducing thixotropic mud to enhance its fluidity, ensuring that the drag-reducing thixotropic mud is fully sheared and stirred before injection, further improving its thixotropic properties and fluidity. Step 5: After grouting is paused, the pump body and motor 31 stop working, disconnect the pump body and grout pipe 3 7, and use the hoisting equipment to lift the second jacking pipe 1 into the starting shaft. During this process, the automatic transmission belt connection mechanism will automatically connect the transmission belt 2 45 inside the first jacking pipe 1 to the transmission wheel 4 29 of the second jacking pipe 1. It is not necessary to set a motor 31 on each jacking pipe 1, which greatly reduces the number of electrical components, reduces energy waste and the cost of setting electric components, and improves construction efficiency and automation level. It is suitable for continuous operation of long-distance trenchless pipe jacking projects. Then start the jacking equipment to push the second jacking pipe 1 into the inner wall of the starting shaft. Step 6: Connect the grout pipe 3 7 on the first jacking pipe 1 and the grout pipe 1 5 on the second jacking pipe 1. Connect the pump body to the grout pipe 3 7 on the second jacking pipe 1. Open valve 1 and all valves 2 on the second jacking pipe 1 to perform grouting. The motor 31 drives the two rotating rods 10 to rotate, thereby agitating the drag-reducing thixotropic mud as it flows through the two chambers 12 to enhance its fluidity. Step 7: Referring to Steps 5 and 6, proceed with the jacking and grouting operations for the subsequent jacking pipe 1.

[0022] If there are many jacking pipes 1, the motor 31 on the first jacking pipe 1 may not be able to drive all the components on the jacking pipe 1 to rotate. In this case, motors 31 can be connected to the mounting bases 26 on several of the jacking pipes 1. All motors 31 have the same speed, so as to drive all the linked components to rotate. This can also reduce the number of electrical components required.

[0023] According to an optional embodiment of the present invention, the mixing tank 8 is slidably connected to the support 9, the mixing tank 8 is connected to the support 9 through an elastic element 14, a slide 19 is slidably connected to the support 9, a tension wheel 18 is rotatably connected to the slide 19, the slide 19 is connected to the support 9 through an elastic element 44, and the tension wheel 18 abuts against the transmission belt 17. The automatic transmission belt connection mechanism includes a first cylinder 20 and a second cylinder 32. The first cylinder 20 is fixedly connected to the support 9. A first cylinder cavity 21 is formed on the first cylinder 20. A piston assembly 22 is slidably connected to the inner wall of the first cylinder cavity 21. The piston assembly 22 extends to the outside of the first cylinder 20. Two spreading wheel assemblies 23 are fixedly connected to the first cylinder 20. The two spreading wheel assemblies 23 spread the second transmission belt 45. A seat cavity 25 is formed on the support 9. The second cylinder 32 is fixedly connected to the support 9. On the seat cavity 25, a second cylindrical cavity 36 is provided on the second cylindrical body 32. The inner wall of the second cylindrical cavity 36 is connected to the inner wall of the first cylindrical cavity 21 through the air pipe 24. A piston assembly 33 is slidably connected to the inner wall of the second cylindrical cavity 36. The piston assembly 33 extends to the outside of the second cylindrical body 32. A wedge block 34 is fixedly connected to the piston assembly 33. The wedge block 34 is connected to the outer wall of the second cylindrical body 32 through an elastic element 35. The wedge block 34 extends to the outside of the seat cavity 25. A frustum component 30 is fixedly connected to the bottom wall of the fourth transmission wheel 29.

[0024] According to an optional embodiment of the present invention, a permanent magnet 27 is embedded in the mounting base 26, a permanent magnet 37, a slide bar 39, a slide plate 41 and an insert 43 are slidably connected to the inner wall of the seat cavity 25, the permanent magnet 37 is fixed to the slide bar 39, the permanent magnet 37 is connected to the inner wall of the seat cavity 25 through an elastic element 38, a push bar 40 is rotatably connected to the slide bar 39, an inclined channel 42 is opened on the slide plate 41, the push bar 40 is slidably connected to the inner wall of the inclined channel 42, the insert 43 is fixed to the slide plate 41, and a groove is opened on the top wall of the mixing tank 8, and a toothed assembly 13 is fixedly connected in the groove.

[0025] In an optional embodiment of the present invention, the front-to-back width of the second cylindrical cavity 36 is greater than the front-to-back width of the first cylindrical cavity 21.

[0026] In step five, the working principle of the automatic belt connection mechanism is as follows: like Figure 2As shown, the left jacking pipe 1 is the first jacking pipe 1, and the right jacking pipe 1 is the second jacking pipe 1. After the left jacking pipe 1 is driven into the inner wall of the starting shaft, the right jacking pipe 1 is lowered into the starting shaft using hoisting equipment. The right jacking pipe 1 is then lowered vertically using a guiding device. The frustum-shaped component 30 on the right jacking pipe 1 pushes the wedge block 34 on the left jacking pipe 1 to the left. The wedge block 34 overcomes the elastic force of the elastic component 35 and moves to the left, pressing the gas in the second cavity 36 through the gas pipe 24 into the first cavity 21. The increased gas in the first cavity 21 pushes the piston assembly 22 to the right, transmitting... The drive belt 245 drives the drive wheel 216 and the mixing box 8 to move to the right against the elastic force of the elastic element 14. Since the front and rear width of the cylinder cavity 236 is greater than the front and rear width of the cylinder cavity 21, the displacement of the piston assembly 22 is greater than the displacement of the piston assembly 23. The spread wheel assembly 23 moves to the right of the drive wheel 429 of the right top pipe 1. The drive wheel 15 pulls the drive belt 17, thereby causing the tension wheel 18 to move forward against the elastic force of the elastic element 444, so that the drive belt 17 is kept taut on the drive wheel 15, the drive wheel 328, and the tension wheel 18.

[0027] As the right-side jacking tube 1 continues to move downward, the wedge block 34 slides along the outer walls of the transmission wheel 29 and the transmission wheel 28. When the top wall of the transmission wheel 28 is lower than the wedge block 34, the transmission wheel 29 has already entered the transmission belt 45. The wedge block 34 loses its thrust and moves to the right under the elastic force of the elastic element 35. The piston assembly 22 moves to the left, so that the transmission belt 45 is fitted onto the right transmission wheel 29 to complete the connection. When the two spreading wheel assemblies 23 move to the left, they will keep spreading the transmission belt 45, thus making the transmission belt 45 taut. The mixing tank 8 moves a small distance to the left under the elastic force of the elastic element 14, and the tensioning wheel 18 moves a small distance backward under the elastic force of the elastic element 44, so that the transmission belt 17 remains taut on the transmission wheel 15, the transmission wheel 28, and the tensioning wheel 18 to facilitate subsequent linkage. At this time, permanent magnet 27 moves to the right of permanent magnet 37. The magnetic repulsion of permanent magnet 27 causes permanent magnet 37 and slider 39 to overcome the elastic force of elastic element 38 and move to the left. Push bar 40 slides in inclined channel 42, thereby driving slider 41 and insert bar 43 to move down. Insert bar 43 is inserted into tooth assembly 13 to limit the mixing box 8 and prevent the mixing box 8 from moving left or right during subsequent transmission.

[0028] The automatic belt connection mechanism of the present invention has the following beneficial effects: Automatic connection and precise connection: Through the cooperation of wedge block 34 and frustum part 30, the automatic docking of transmission belt 2 45 and transmission wheel 4 29 is achieved during the installation of pipe jacking 1, without manual intervention, thus improving construction efficiency and assembly accuracy. Pneumatic self-balancing linkage structure design: Cylinder 1 21 and Cylinder 2 36 are connected by air pipe 24. Gas compression and expansion drive piston assembly 1 22 and piston assembly 2 33 to achieve synchronous movement. The structure is simple and the response is fast, which is beneficial to the connection operation of transmission belt 2 45. Cooperative positioning of the spreading wheel assembly 23: During the advancement process, the spreading wheel assembly 23 spreads and guides the transmission belt 2 45 to keep it in a spread state, thereby improving the reliability and success rate of the transmission wheel 4 29 fitting into the transmission belt 2 45 and avoiding jamming or misalignment; Adaptive limit reset function: Elastic element 14, elastic element 2 35, elastic element 3 38, and elastic element 44 provide self-resetting capability for mixing tank 8, wedge block 34, slide bar 39, and tensioning wheel 18, respectively. Magnetic assisted locking mechanism: The repulsive force generated between permanent magnet 27 and permanent magnet 37 drives the slider 39 and slider 41 to move, and drives the insert 43 to insert into the tooth assembly 13 to complete the limiting of the mixing tank 8, effectively preventing the rotating rod 10 from axially slipping during high-speed rotation and improving the stability of the transmission belt 17. Compact structure adaptable to various pipe jacking diameters: The entire automatic transmission belt connection mechanism is set between the support 9 and the mounting base 26, occupying little space and adaptable to various pipe jacking application scenarios with different inner diameter specifications, and has good adaptability for promotion.

[0029] According to an optional embodiment of the present invention, the slurry storage tank is provided with a stirring device, which can continuously stir the drag-reducing thixotropic mud in the slurry storage tank, so that the drag-reducing thixotropic mud maintains uniform particle dispersion during the standing period, avoiding sedimentation or stratification, thereby giving the drag-reducing thixotropic mud good fluidity and stability in the initial grouting state, which is conducive to the smooth progress of subsequent grouting work.

[0030] According to an optional embodiment of the present invention, a pressure sensor is provided on the branch pipe 4. The pressure sensor monitors the ejection pressure of the drag-reducing thixotropic mud in real time. When the pressure is abnormal, the external alarm device can issue an early warning or adjust the pump output in time, thereby improving construction safety and the uniformity of the drag-reducing thixotropic mud distribution.

[0031] In an optional embodiment of the present invention, both permanent magnet 27 and permanent magnet 37 are made of neodymium, iron and boron, so that permanent magnet 27 and permanent magnet 37 have strong magnetism and resistance to demagnetization.

[0032] According to an optional embodiment of the present invention, the drag-reducing thixotropic mud material comprises a starch-based modifier and a vegetable oil emulsion, which can significantly enhance the thixotropic and lubricating properties of the drag-reducing thixotropic mud, improve the flow state of the drag-reducing thixotropic mud during the pipe jacking process, and reduce pipe wall friction. The starch-based modifier is added at 0.5% of the total mud mass, and the starch-based modifier can be selected as hydroxypropyl starch. The vegetable oil emulsion is added at 1.5% of the total mud mass. According to an optional embodiment of the present invention, the inner diameter of the first slurry tube 5, the second slurry tube 6, and the third slurry tube 7 is 30-50 mm.

[0033] According to an optional embodiment of the present invention, the spacing between any two adjacent T-pipes 3 on the ring pipe 2 is equal, ensuring that the drag-reducing thixotropic mud is evenly distributed along the outer wall of the jacking pipe 1, which is beneficial to forming a continuous and stable lubrication layer and improving the overall propulsion efficiency.

[0034] The components, modules, mechanisms, and devices in this invention that are not described in detail are all general standard parts or components known to those skilled in the art. Their structures and principles can be learned by those skilled in the art through technical manuals or conventional experimental methods.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. A method of drilling with a thixotropic mud characterized in that, It comprises the following steps: Step one, excavate the starting well, arrange the jacking equipment, slurry storage tank and pump body in the starting well, fill the slurry storage tank with drag reduction thixotropic slurry, connect the pump body and the slurry storage tank, and arrange hoisting equipment on the ground; Step two, transport all the pipe jacking to be installed to the ground near the starting well; The inner wall of the pipe jacking is fixedly connected with a ring pipe, the ring pipe is fixedly connected with slurry pipe one and slurry pipe two, the slurry pipe one is provided with valve one, the ring pipe is fixedly connected with four and more than three pipe, the three pipe is fixedly connected with a branch pipe, the branch pipe is provided with valve two, one end of the branch pipe extends to the outer wall of the pipe jacking, the inner wall of the pipe jacking is fixedly connected with a support and a mounting seat, the support is connected with a stirring box, the stirring box is connected with slurry pipe two and slurry pipe three, the stirring box is provided with a box cavity, the inner wall of the box cavity is rotatably connected with a rotating rod, the rotating rod is fixedly connected with two and more than stirring blades, the lower end of the rotating rod extends to below the stirring box, the lower end of the rotating rod is fixedly connected with transmission wheel one, the bottom wall of the transmission wheel one is fixedly connected with transmission wheel two, the inner wall of the pipe jacking is connected with a transmission belt automatic connection mechanism, transmission belt two is connected between the transmission wheel two and the transmission belt automatic connection mechanism, the bottom wall of the mounting seat is rotatably connected with transmission wheel three, the bottom wall of the transmission wheel three is fixedly connected with transmission wheel four, the transmission wheel three is connected with the transmission wheel one through transmission belt one; Step three, install the first pipe jacking: install the motor on the mounting seat of the first pipe jacking, and connect the rotor of the motor with the transmission wheel three; Step four, use the hoisting equipment to hoist the first pipe jacking into the starting well, start the jacking equipment to jack the first pipe jacking into the inner wall of the starting well, connect the slurry pipe three with the pump body, close the valve one, open all the valve two, open the pump body and the motor, so that the drag reduction thixotropic slurry is sprayed from each branch pipe to the outer wall of the pipe jacking for lubrication, when the drag reduction thixotropic slurry passes through the box cavity, the motor rotor indirectly drives the stirring blades to rotate, and the stirring blades stir the drag reduction thixotropic slurry to enhance the fluidity thereof; Step five, after the grouting is temporarily stopped, the pump body and the motor are temporarily stopped, the connection between the pump body and the slurry pipe three is released, the second pipe jacking is hoisted into the starting well by using the hoisting equipment, in this process, the transmission belt automatic connection mechanism automatically connects the transmission belt two in the first pipe jacking to the transmission wheel four of the second pipe jacking, and the jacking equipment is started to jack the second pipe jacking into the inner wall of the starting well; Step six, connect the slurry pipe three on the first pipe jacking with the slurry pipe one on the second pipe jacking, connect the pump body with the slurry pipe three on the second pipe jacking, open the valve one and all the valve two on the second pipe jacking, so as to carry out grouting, the motor drives the two rotating rods to rotate, so as to stir the drag reduction thixotropic slurry flowing through the two box cavities to enhance the fluidity thereof; Step seven, refer to steps five and six to carry out jacking and grouting operation on the subsequent pipe jacking.

2. A method of reducing drag in a thixotropic mud slurry according to claim 1, wherein The stirring box is slidably connected to the support, the stirring box is connected to the support through the elastic element one, the support is slidably connected with a sliding seat, the sliding seat is rotatably connected with a tensioning wheel, the sliding seat is connected with the support through the elastic element four, and the tensioning wheel abuts against the transmission belt one. The automatic connecting mechanism of the transmission belt comprises a cylinder one and a cylinder two, the cylinder one is fixedly connected to the support, a cylinder cavity one is formed in the cylinder one, a piston assembly one is slidably connected to the inner wall of the cylinder cavity one, the piston assembly one extends to the outside of the cylinder one, two opening wheel assemblies are fixedly connected to the cylinder one, the two opening wheel assemblies open the transmission belt two, a seat cavity is formed in the support, the cylinder two is fixedly connected to the seat cavity, a cylinder cavity two is formed in the cylinder two, the inner wall of the cylinder cavity two is communicated with the inner wall of the cylinder cavity one through an air pipe, a piston assembly two is slidably connected to the inner wall of the cylinder cavity two, the piston assembly two extends to the outside of the cylinder two, a wedge-shaped block is fixedly connected to the piston assembly two, the wedge-shaped block is connected to the outer wall of the cylinder two through an elastic element two, the wedge-shaped block extends to the outside of the seat cavity, and the bottom wall of the transmission wheel four is fixedly connected with a circular table piece.

3. A method of reducing drag in a thixotropic mud slurry according to claim 2, wherein The mounting seat is inlaid with a permanent magnet one, the inner wall of the seat cavity is slidably connected with a permanent magnet two, a sliding bar, a sliding sheet and an insertion bar, the permanent magnet two is fixedly connected to the sliding bar, the permanent magnet two is connected to the inner wall of the seat cavity through an elastic element three, the sliding bar is rotatably connected with a pushing bar, the sliding sheet is provided with an inclined channel, the pushing bar is slidably connected to the inner wall of the inclined channel, and the insertion bar is fixedly connected to the sliding sheet.

4. A method of reducing drag in a thixotropic mud slurry according to claim 3, wherein The front-to-back width of the cylinder cavity two is greater than that of the cylinder cavity one.

5. A method of reducing drag in a thixotropic mud slurry according to claim 4, wherein The slurry storage tank is provided with a stirring device.

6. A method of reducing drag in a thixotropic mud slurry according to claim 5, wherein The branch pipe is provided with a pressure sensor, which monitors the ejection pressure of the drag-reducing thixotropic mud in real time.

7. A method of reducing drag in a thixotropic mud slurry according to claim 6, wherein The materials of the permanent magnet one and the permanent magnet two comprise neodymium, iron and boron.

8. A method of constructing a thixotropic mud with drag reduction according to any one of claims 1 to 7, characterized in that, The material of the drag-reducing thixotropic mud comprises a starch-based modifier and a vegetable oil emulsion.

9. A method of reducing drag in a thixotropic mud slurry according to claim 8, wherein, The inner diameters of the slurry pipe one, the slurry pipe two and the slurry pipe three are 30-50 mm.

10. A method of reducing drag in a thixotropic mud slurry according to claim 9, wherein, The distance between every two adjacent three-way pipes on the ring pipe is equal.

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