An anti-stagnant structure, a tunneling machine and its control method

Abstract

This invention discloses an anti-sludge-drainage structure, a tunnel boring machine (TBM), and its control method, relating to the field of tunnel construction technology. The anti-sludge-drainage structure includes a mixing assembly connected to the cutterhead rotating section and covering the slurry discharge pipe opening; cutterhead crushing blocks and shield crushing blocks arranged opposite each other to form a toothed crushing gap; and a high-pressure flushing assembly facing the screen holes of the conical crushing structure. The TBM incorporates the aforementioned anti-sludge-drainage structure, and the control method offers three operating modes: linkage, timed / interval, and manual / remote control. This invention, through the synergistic effect of mixing, crushing, and flushing, disrupts the conditions for mud cake formation in highly viscous strata at the source, achieving proactive prevention and rapid clearing of sludge, significantly improving the geological adaptability and construction continuity of the TBM, avoiding high-risk manual entry operations, and demonstrating outstanding overall economic benefits.

Description

Technical Field

[0001] This invention relates to the field of tunneling machine slurry discharge technology, and in particular to an anti-stagnant slurry discharge structure, a tunneling machine and its control method. Background Technology

[0002] Pipe jacking machines have become the mainstay of urban underground pipeline and trenchless construction, widely used in various underground engineering projects such as water supply and drainage, power, communications, and gas. Among them, slurry balance pipe jacking machines balance the water and soil pressure at the excavation face by adjusting the pressure in the slurry chamber and using circulating slurry to carry the excavated soil. They have advantages such as minimal disturbance to the strata, high construction accuracy, and suitability for complex strata, and have been widely used in construction in soft soil, sandy soil, and composite strata.

[0003] However, when using a slurry-balanced pipe jacking machine in highly viscous strata, the viscous excavated soil easily clumps and forms hard "mud cakes" within the slurry chamber, leading to "chamber blockage" or "stagnation in discharge," resulting in interrupted discharge, pressure imbalance in the slurry chamber, and construction halt. Existing solutions to these problems mainly include: optimizing the cutterhead design by using a cutterhead with a smaller opening ratio to limit the particle size of the excavated soil entering the slurry pipe and prevent blockage; however, this solution has low adaptability to different strata and cannot successfully discharge excavated soil in gravel and pebble strata; adjusting slurry performance parameters by increasing slurry viscosity and specific gravity to improve excavated soil carrying capacity, but the effect is limited and significantly increases slurry treatment costs; manual entry into the chamber to clean the mud cakes and unclog the discharge pipes poses extremely high safety risks and is inefficient, often requiring several days for a single cleaning, severely impacting construction progress.

[0004] Some existing technologies propose secondary crushing schemes, using a crushing device between the cutterhead and the front shield partition to break up large pieces of excavated soil. However, this type of device is positioned forward and can only perform preliminary treatment on the excavated soil entering the front slurry chamber. It cannot specifically mix and crush the excavated soil entering the rear slurry chamber and about to enter the discharge pipe, thus failing to effectively solve the problem of sludge cake formation and subsequent backflow in high-viscosity formations. Therefore, developing a compact, efficient, and reliable anti-backflow technology is of great significance for improving the adaptability of slurry balance pipe jacking machines to complex formations.

[0005] It should be noted that the above technical information is the result of the applicant's inventive analysis. This explanation is only intended to enhance the understanding of the general background technology of this application by those skilled in the art, and should not be regarded as an admission or implication in any form that the following technical information constitutes prior art known to those skilled in the art. Summary of the Invention

[0006] To address the shortcomings in the aforementioned background technology, this invention proposes an anti-blockage structure, a tunneling machine, and its control method. The technical problem to be solved is that existing slurry balance pipe jacking machines are prone to blockage and blockage when constructing in high-viscosity strata, and existing solutions suffer from low efficiency, high risk, and poor geological adaptability.

[0007] The technical solution of this invention is as follows:

[0008] An anti-stagnant drainage structure is applied to a tunneling machine comprising a cutterhead, a shield, a conical crushing structure, and a slurry discharge pipe. The anti-stagnant drainage structure includes a mixing assembly, a central crushing assembly, and a high-pressure flushing assembly. The mixing assembly is connected to the rotating part of the cutterhead and is located within the rear slurry chamber formed by the front and rear partitions of the shield. The mixing area of ​​the mixing assembly completely or partially covers the inlet of the slurry discharge pipe. The central crushing assembly includes cutterhead crushing blocks and shield crushing blocks. The cutterhead crushing blocks are connected to the outer circumferential surface of the cutterhead rotating part, and the shield crushing blocks are connected to the inner ring surface of the front partition of the shield. The cutterhead crushing blocks and the shield crushing blocks are arranged opposite each other, forming a toothed crushing gap. The high-pressure flushing assembly includes a high-pressure water pipeline connected to a high-pressure water nozzle. The high-pressure water nozzle is located at the bottom of the conical crushing structure, and the spray direction of the high-pressure water nozzle includes the screen holes of the conical crushing structure.

[0009] The beneficial effects of this technical solution are as follows: by setting up a stirring component linked to the cutterhead in the rear mud and water chamber, the slag about to enter the discharge pipe can be continuously stirred, fundamentally destroying the conditions for the formation of mud cake in high-viscosity strata and preventing the slag from accumulating near the discharge pipe opening; the central crushing component can perform secondary shearing and crushing of large pieces of slag in the central area of ​​the cutterhead, improving the slag feeding efficiency and preventing large pieces of slag from clogging the screen holes of the conical crushing structure; the high-pressure flushing component can quickly clear the screen holes and discharge channels of the conical crushing structure when sludge discharge occurs. The three components work together to achieve proactive prevention and rapid treatment of sludge discharge.

[0010] Furthermore, the mixing assembly includes at least one mixing rod extending radially along the rear mud-water chamber. The mixing rod is clearance-fitted with the rear side of the front partition of the shield and the front side of the rear partition of the shield. The advantages of this technical solution are: the radially extending mixing rod can cover a larger mixing range, and the clearance fit with the front and rear partitions ensures smooth rotation of the mixing rod while effectively scraping away sticky slag adhering to the partition surface, further preventing mud cake formation.

[0011] Furthermore, the stirring rod is provided with several overflow holes and / or reinforcing ribs. The beneficial effects of this technical solution are: the overflow holes can reduce the resistance when the stirring rod rotates and reduce the torque consumption of the cutter head; the reinforcing ribs can improve the structural strength of the stirring rod and prevent it from deforming or breaking under high load conditions.

[0012] Furthermore, the surfaces of the cutterhead crushing blocks and / or the shield crushing blocks and / or the stirring assembly are all provided with a wear-resistant layer. The beneficial effects of this technical solution are that the wear-resistant layer can significantly improve the service life of easily worn parts, reduce the frequency of equipment maintenance, and extend the continuous working time of the equipment.

[0013] Furthermore, several high-pressure water nozzles are provided, each distributed at intervals along the bottom of the conical crushing structure, and the spray angle of each high-pressure water nozzle is adjustable. The beneficial effects of this technical solution are: multiple spaced nozzles can achieve omnidirectional coverage of the screen holes in the conical crushing structure, and the adjustable spray angle can precisely flush according to the location of the blockage, improving unblocking efficiency.

[0014] Furthermore, the high-pressure water pipeline is equipped with a pressure regulating valve and a flow regulating valve. The advantages of this technical solution are: it allows for flexible adjustment of the pressure and flow rate of the high-pressure water according to the degree of blockage, ensuring effective unblocking while conserving water resources and energy.

[0015] The present invention also provides a tunneling machine, including a cutterhead, a shield body, a main drive, a slurry discharge pipe, a conical crushing structure, and an anti-stagnant slurry discharge structure as described in any one of the above. The shield body is internally divided into a front slurry chamber and a rear slurry chamber by a front partition and a rear partition. The main drive is fixed on the rear partition of the shield body. The cutterhead passes through the front slurry chamber and the rear slurry chamber in sequence and is connected to the main drive. The conical crushing structure is disposed in the front slurry chamber. The conical crushing structure and the crushing structure arranged on the torsion leg of the cutterhead form a shearing and crushing mechanism. The suction port of the slurry discharge pipe is located in the rear slurry chamber.

[0016] The beneficial effects of this technical solution are: it integrates the anti-stagnant drainage structure into the internal space of the existing tunneling machine without requiring major modifications to the main structure of the tunneling machine. The structure is compact, the modification cost is low, and it can be directly applied to various existing slurry balance pipe jacking machines, significantly improving their anti-stagnant drainage capabilities.

[0017] Furthermore, the rear partition of the shield body is provided with a first stirring rod mounting hole corresponding to the radial position of the stirring assembly, and the stirring rod mounting hole is connected to a sealing element; and / or the outer periphery of the shield body is provided with a second stirring rod mounting hole corresponding to the axial position of the stirring assembly, and the second stirring rod mounting hole is connected to a sealing element. The beneficial effects of this technical solution are: it provides multiple stirring rod installation methods, can adapt to tunneling machines with different structures, and the sealing element can effectively prevent mud leakage in the slurry chamber, ensuring construction safety.

[0018] This invention also provides a tunneling machine control method, applied to the aforementioned tunneling machine. The control method includes at least one of the following operating modes: a linkage control mode, which collects the main jacking force, cutterhead torque, mud discharge flow rate, and mud specific gravity parameters of the tunneling machine in real time; when the main jacking force and / or cutterhead torque are detected to be continuously increasing and the mud discharge flow rate is decreasing, the high-pressure flushing component is automatically activated, and the flushing pressure and / or flushing angle and / or flushing flow rate are adjusted according to the parameter changes; a timed / interval operating mode, which automatically activates the high-pressure flushing component for preventive flushing according to a preset time interval; and a manual / remote control mode, which receives manual control commands and controls the start / stop and operating parameters of the high-pressure flushing component.

[0019] The beneficial effects of this technical solution are as follows: it provides multiple intelligent control modes, enabling automatic early warning and handling of stagnant discharge without manual intervention, thus improving the level of automation in construction; preventive flushing can promptly remove potential blockage hazards before stagnant discharge occurs, further improving the continuity of construction.

[0020] Furthermore, in the linkage control mode, when the cutterhead torque exceeds 70% of the rated torque for more than 30 seconds, and the sludge discharge flow rate is lower than 50% of the rated flow rate, the high-pressure flushing component is activated with an initial pressure of 10 MPa. If the parameters do not return to normal within 5 minutes, the pressure is increased to 15 MPa. In the timed / interval operation mode, the preset time interval is 10-60 minutes, and each flushing session lasts 30-120 seconds. The beneficial effects of this technical solution are: through extensive engineering practice, the optimal control parameters have been determined, which can minimize the use of high-pressure water and reduce construction costs while ensuring the anti-stagnant discharge effect.

[0021] In summary, compared with existing technologies, this invention allows the same pipe jacking machine to adapt to a wider range of geological formations, increasing equipment versatility and geological adaptability. It shifts from passive response to active intervention, solving the persistent problem of drainage sludge in complex geological formations during slurry pipe jacking, greatly improving the continuity and reliability of construction. It avoids the high-risk, low-efficiency "manual entry" operation, ensuring the safety of construction personnel and reducing the risk of accidents. Simultaneously, it significantly reduces downtime caused by drainage issues, increases monthly advance rate, and yields significant overall economic benefits. It has the following significant beneficial effects:

[0022] Strong geological adaptability: Through the synergistic effect of stirring, crushing and scouring, this invention can effectively solve the problem of stagnation in high-viscosity strata when the slurry balance pipe jacking machine is constructed, while not affecting its normal construction in other strata such as gravel and pebbles. This allows the same pipe jacking machine to adapt to a wider range of geological conditions and increases the versatility of the equipment.

[0023] High construction efficiency: This invention changes the passive response to blockage to active intervention, enabling prevention before blockage occurs and rapid clearing after it occurs, greatly reducing downtime caused by blockage and significantly improving monthly progress rate, resulting in outstanding overall economic benefits.

[0024] High safety: This invention completely avoids the high-risk and low-efficiency manual warehouse entry operations, ensuring the safety of construction personnel and reducing the risk of accidents.

[0025] Compact structure and low modification cost: The anti-stagnant drainage structure of the present invention is integrated into the existing internal space of the tunneling machine. It does not require major modifications to the main structure and can be directly applied to existing equipment. The modification cost is low and it is easy to promote and apply.

[0026] High degree of automation: The control method of this invention provides three intelligent operation modes, which can realize automatic detection, early warning and handling of stagnation, reduce the intensity of manual operation and improve the level of intelligence of construction. Attached Figure Description

[0027] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0028] Figure 1 This is a sectional view of the tunneling machine of the present invention from the side view direction;

[0029] Figure 2 This is a front view of the central crushing component of the present invention;

[0030] Figure 3 This is a side view of the cutter head of the present invention.

[0031] Figure 4 This is a front view of the high-pressure flushing component of the shield body in this invention.

[0032] Explanation of reference numerals in the attached figures:

[0033] 1-Cutterhead, 2-Shield body, 3-Slurry discharge pipe, 4-Main drive, 5-Rear mud and water chamber, 6-Front mud and water chamber, 101-Agitator rod, 102-Cutterhead crushing block, 103-Crushing structure, 104-Overflow hole, 105-Reinforcing rib;

[0034] 201-Conical crushing structure, 202-High-pressure water nozzle, 203-Shield body crushing block, 204-Front partition of shield body, 205-Rear partition of shield body, 206-High-pressure water pipeline, 207-Agitator rod mounting hole one, 208-Agitator rod mounting hole two. Detailed Implementation

[0035] 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 core concept of the present invention and the following embodiments, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] These embodiments are provided to make the application thorough and complete, and to fully express the scope of the application to those skilled in the art. It should be noted that, unless otherwise specifically stated, the relative arrangement of components and steps, material composition, numerical expressions, and values ​​illustrated in these embodiments should be interpreted as merely exemplary and not as limiting.

[0037] It should be noted that, in the description of this application, unless otherwise stated, "several" means greater than or equal to one; the terms "upper," "lower," "left," "right," "inner," "outer," "axial," "radial," etc., indicating orientation or positional relationships are only for the convenience of describing this application 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 on this application. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0038] Furthermore, the terms "first," "second," and similar words used in this application do not indicate any order, quantity, or importance, but are merely used to distinguish different parts. "Vertical" is not strictly vertical, but within the permissible margin of error. "Parallel" is not strictly parallel, but within the permissible margin of error. Words such as "including" or "contains" mean that the element preceding the word encompasses the element listed after the word, and do not exclude the possibility of encompassing other elements as well.

[0039] It should also be noted that, in the description of this application, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" 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 an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application depending on the specific circumstances. When a specific device is described as being located between a first device and a second device, an intermediary device may or may not be present between the specific device and the first or second device.

[0040] All terms used in this application have the same meaning as understood by one of ordinary skill in the art to which this application pertains, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries should be interpreted as having meanings consistent with their meanings in the context of the relevant art, and not as idealized or highly formalized, unless expressly defined herein.

[0041] Techniques, methods, and equipment known to those skilled in the art may not be discussed in detail, but where appropriate, they should be considered part of the specification.

[0042] Basic Implementation

[0043] This embodiment provides an anti-stagnant structure and a tunneling machine including the structure, such as Figure 1 As shown. The tunneling machine includes a cutterhead 1, a shield 2, a main drive 4, a slurry discharge pipe 3, and a conical crushing structure 201. The shield 2 is internally divided into a front slurry chamber 6 and a rear slurry chamber 5 by a front partition 204 and a rear partition 205. The main drive 4 is fixed to the rear partition 205. The cutterhead 1 passes through the front slurry chamber 6 and the rear slurry chamber 5 in sequence and connects to the output end of the main drive 4. The conical crushing structure 201 is located in the front slurry chamber 6. The conical crushing structure 201 and the crushing structure arranged on the torsion legs of the cutterhead 1 form a shearing and crushing mechanism. The suction inlet of the slurry discharge pipe 3 is located in the rear slurry chamber 5.

[0044] The anti-stagnant structure includes a mixing assembly, a central crushing assembly, and a high-pressure flushing assembly. For example... Figure 3 As shown, the mixing assembly includes a mixing rod 101. One end of the mixing rod 101 is fixedly connected to the rotating part of the cutterhead 1 and extends radially along the rear mud-water chamber 5. The mixing area of ​​the mixing rod 101 completely covers the inlet of the discharge pipe 3. The mixing rod 101 is clearance-fitted with the rear side of the front partition 204 of the shield body and the front side of the rear partition 205 of the shield body, with a clearance of 40mm. The length of the mixing rod 101 is 75% of the radial length of the rear mud-water chamber 5 to avoid interference with the slurry inlet pipe.

[0045] like Figure 2 As shown, the central crushing assembly includes a cutterhead crushing block 102 and a shield crushing block 203. The cutterhead crushing block 102 is fixedly connected to the outer circumferential surface of the rotating part of the cutterhead 1, and the shield crushing block 203 is fixedly connected to the inner ring surface of the shield front partition 204. The cutterhead crushing block 102 and the shield crushing block 203 are arranged opposite to each other and form a toothed crushing gap with a gap width of 30mm.

[0046] like Figure 4As shown, the high-pressure flushing assembly includes a high-pressure water nozzle 202 and a high-pressure water pipeline 206. The high-pressure water nozzle 202 is located at the bottom of the conical crushing structure 201, and the spray direction of the high-pressure water nozzle 202 is towards the screen hole position of the conical crushing structure 201. One end of the high-pressure water pipeline 206 is connected to the high-pressure water nozzle 202, and the other end is connected to the high-pressure water system of the tunneling machine.

[0047] The working principle of this embodiment is as follows: During tunneling machine construction, the main drive 4 drives the cutterhead 1 to rotate and cut the strata. The cut excavated soil enters the front slurry chamber 6 and mixes with the mud to form a slurry. The slurry is first initially crushed by the shearing and crushing mechanism formed by the conical crushing structure 201 and the crushing structure 103 arranged on the back of the twisting leg of the cutterhead 1. Then, it enters the rear slurry chamber 5 through the screen holes of the conical crushing structure 201. The stirring rod 101 rotates synchronously with the cutterhead 1, continuously stirring the slurry in the rear slurry chamber 5 to prevent the sticky soil from sticking together and forming mud cakes, and pushes the slurry towards the suction port of the discharge pipe 3 for discharge. At the same time, large pieces of soil in the central area of ​​the cutterhead 1 are sheared and crushed a second time when passing through the toothed crushing gap formed by the cutterhead crushing block 102 and the shield crushing block 203 during the rotation of the cutterhead 1, ensuring that they can pass smoothly through the screen holes of the conical crushing structure 201. When the screen holes of the cone crushing structure 201 become blocked, the high-pressure flushing component is activated. High-pressure water is delivered to the high-pressure water nozzle 202 through the high-pressure water pipeline 206 and sprayed onto the screen hole to disperse the blocked slag and clear the slurry discharge channel.

[0048] Optimized Example 1

[0049] This embodiment optimizes the stirring assembly based on the basic embodiment. For example... Figure 3 As shown, the stirring assembly includes three stirring rods 101, evenly distributed along the circumference of the rotating part of the cutter head 1. Each stirring rod 101 is provided with several overflow holes 104 with a diameter of 20 mm, which are spaced apart along the axial direction of the stirring rod 101 at intervals of 150 mm. Meanwhile, reinforcing ribs 105 are welded to both the upper and lower surfaces of the stirring rods 101, extending along the length of the stirring rod 101 with a height of 15 mm.

[0050] This embodiment expands the mixing range and improves mixing efficiency by increasing the number of mixing rods; the overflow hole can effectively reduce the resistance when the mixing rod rotates, reducing the torque consumption of the cutter head by about 15%; the reinforcing ribs significantly improve the structural strength of the mixing rod, enabling it to withstand greater loads and making it suitable for construction conditions of high-viscosity, high-density slag.

[0051] Optimized Example 2

[0052] This embodiment adds a wear-resistant layer design to the basic embodiment. A wear-resistant alloy layer is deposited on the surfaces of the cutterhead crushing block 102, the shield crushing block 203, and the stirring rod 101. The thickness of the wear-resistant layer is 5mm. The wear-resistant alloy layer is made of tungsten carbide alloy material, which has extremely high hardness and wear resistance.

[0053] This embodiment, by incorporating a wear-resistant layer, significantly improves the service life of easily worn components. Tests have shown that, under the same operating conditions, components with a wear-resistant layer have a service life 3-5 times longer than those without, substantially reducing equipment maintenance frequency and costs, and extending the equipment's continuous operating time.

[0054] Optimized Example 3

[0055] This embodiment optimizes the high-pressure flushing component based on the basic embodiment. There are four high-pressure water nozzles 202, evenly distributed along the bottom circumference of the conical crushing structure 201. Each high-pressure water nozzle 202 is connected to a high-pressure water pipeline 206 via a universal joint, and the spray angle can be adjusted within the range of 30°-90°. A pressure regulating valve and a flow regulating valve are connected in series on the high-pressure water pipeline 206. The pressure regulating valve has an adjustment range of 5MPa-20MPa, and the flow regulating valve has an adjustment range of 10L / min-50L / min.

[0056] This embodiment utilizes multiple adjustable-angle high-pressure water nozzles to achieve omnidirectional coverage of the 201 sieve holes in the conical crushing structure. The spray angle can be flexibly adjusted according to the location of the blockage for precise flushing. Pressure and flow control valves can flexibly adjust the pressure and flow rate of the high-pressure water according to the degree of blockage. For minor blockages, lower pressure and flow rate can be used for flushing; for severe blockages, pressure and flow rate can be increased to ensure effective unblocking.

[0057] Optimized Example 4

[0058] This embodiment optimizes the installation structure of the mixing rod of the tunneling machine based on the basic embodiment. The rear bulkhead 205 of the shield body has a mixing rod mounting hole 207 corresponding to the radial position of the mixing rod 101. The mixing rod mounting hole 207 is a through hole with a diameter 100mm larger than the diameter of the mixing rod 101. The mixing rod mounting hole 207 is normally sealed with a sealing cover. When it is necessary to replace or maintain the mixing rod 101, the sealing cover can be opened for operation.

[0059] The sealing pressure of the sealing cover is 2MPa, which is not less than 1.5 times the maximum working pressure of the mud and water chamber. At the same time, the outer periphery of the shield body 2 is provided with a stirring rod mounting hole 208 corresponding to the axial position of the stirring rod 101, and a mechanical seal is installed in the stirring rod mounting hole 208.

[0060] This embodiment provides two methods for installing and maintaining the mixing rod. Mixing rod mounting hole 1 (207) is used for replacing and maintaining the mixing rod without disassembling other parts of the tunneling machine, making operation convenient and quick. Mixing rod mounting hole 2 (208) is used for the conventional installation of the mixing rod. After installation, mixing rod mounting hole 2 (208) is sealed by welding a steel plate. The seals corresponding to mixing rod mounting holes 1 (207) and 2 (208) effectively prevent mud leakage from the mud chamber, ensuring construction safety.

[0061] Optimized Example 5

[0062] This embodiment provides a control method for a tunneling machine, applied to the aforementioned tunneling machine. The control method includes three operating modes: a linkage control mode, a timed / interval operation mode, and a manual / remote control mode.

[0063] In the linkage control mode, the tunneling machine's control system collects four key parameters in real time: main jacking force, cutterhead torque, sludge discharge flow rate, and sludge specific gravity. When the cutterhead torque exceeds 70% of the rated torque for more than 30 seconds, and the sludge discharge flow rate is lower than 50% of the rated flow rate, the control system determines that there is a risk of sludge retention and automatically activates the high-pressure flushing component, with an initial flushing pressure of 10 MPa and a flow rate of 30 L / min. If the cutterhead torque and sludge discharge flow rate do not return to normal within 5 minutes, the control system automatically increases the flushing pressure to 15 MPa and the flow rate to 40 L / min. If the parameters still do not return to normal after 10 minutes, the control system issues an audible and visual alarm signal, prompting the operator to switch to manual mode for handling.

[0064] In timed / interval operation mode, the operator can preset the flushing interval and the flushing time according to the formation conditions. In highly viscous and easily muddy formations, the preset interval is 20 minutes and the flushing time is 60 seconds; in general viscous formations, the preset interval is 40 minutes and the flushing time is 30 seconds. The control system automatically starts the high-pressure flushing component at the preset intervals to perform preventative flushing, promptly removing the viscous soil adhering to the screen holes and preventing blockage.

[0065] In manual / remote control mode, the operator can directly control the start / stop, flushing pressure, flow rate, and jet angle of the high-pressure flushing components via a touchscreen or remote control in the control room. When obvious signs of sludge buildup are observed or the linkage control mode fails to effectively resolve the blockage, the operator can switch to manual mode for precise control based on the actual situation to ensure rapid unblocking of the slurry discharge channel.

[0066] Preferred Implementation

[0067] This embodiment represents the optimal implementation that encompasses all the aforementioned optimized features. The anti-stagnant structure includes three stirring rods 101 evenly distributed along the circumference of the rotating part of the cutterhead 1. Each stirring rod 101 extends radially along the rear mud-water chamber 5, with a length equal to 80% of the radial length of the rear mud-water chamber 5. The fitting clearance between the stirring rod 101 and the front partition 204 and rear partition 205 of the shield body is 35mm. The stirring rod 101 is provided with several overflow holes and reinforcing ribs, and a 5mm thick tungsten carbide wear-resistant layer is welded to its surface.

[0068] The surfaces of the cutterhead crushing block 102 and the shield crushing block 203 of the central crushing assembly are both overlaid with a 6mm thick wear-resistant alloy layer, and the toothed crushing gap width is 25mm.

[0069] The high-pressure flushing assembly includes four high-pressure water nozzles 202 evenly distributed along the bottom circumference of the conical crushing structure 201, with the spray angle of each nozzle adjustable within the range of 45°-75°. The high-pressure water pipeline 206 is equipped with a pressure regulating valve and a flow regulating valve, with adjustment ranges of 5MPa-20MPa and 10L / min-50L / min, respectively.

[0070] The rear bulkhead 205 of the tunnel boring machine's shield has three agitator mounting holes 207, each equipped with a mechanical seal with a sealing pressure of 2.5 MPa. The outer periphery of the shield 2 has three corresponding agitator mounting holes 208, which are normally sealed with sealing caps.

[0071] The control method supports linkage control mode, timed / interval operation mode, and manual / remote control mode. In linkage control mode, when the cutter head torque exceeds 70% of the rated torque for 30 seconds, and the sludge discharge flow rate is lower than 50% of the rated flow rate, high-pressure flushing is automatically initiated with an initial pressure of 10 MPa and a flow rate of 30 L / min; if it does not recover within 5 minutes, the pressure is increased to 15 MPa and the flow rate is increased to 40 L / min. In timed / interval operation mode, the preset time interval is 30 minutes, and each flushing session lasts 45 seconds.

[0072] The complete working process of this embodiment is as follows: When the tunneling machine is working in high-viscosity strata, the cutterhead 1 rotates to cut the strata, and the excavated soil enters the front slurry chamber 6. After being initially crushed by the conical crushing structure 201, it enters the rear slurry chamber 5. Three stirring rods 101 rotate synchronously with the cutterhead 1, stirring the excavated soil in the rear slurry chamber 5 in all directions, disrupting the conditions for mud cake formation, and pushing the excavated soil towards the discharge pipe 3. Large pieces of excavated soil in the central area of ​​the cutterhead are crushed twice by the central crushing component and pass smoothly through the screen holes. The control system automatically starts the high-pressure flushing component at preset 30-minute intervals for preventive flushing, with each flush lasting 45 seconds, to remove the adhering excavated soil from the screen holes.

[0073] When slight blockage occurs, the cutter head torque increases to 75% of the rated torque, and the sludge discharge flow rate decreases to 45% of the rated flow rate. The control system automatically initiates high-pressure flushing at 10 MPa pressure and 30 L / min flow rate. After 3 minutes, the parameters return to normal, and flushing automatically stops. When severe blockage occurs, the cutter head torque increases to 85% of the rated torque, and the sludge discharge flow rate decreases to 30% of the rated flow rate. The control system initiates high-pressure flushing with an initial pressure of 10 MPa. If the parameters do not recover after 5 minutes, the pressure is automatically increased to 15 MPa. After another 3 minutes, the parameters return to normal, and flushing stops. In special circumstances where the linkage control mode cannot resolve the issue, the operator can switch to manual mode, adjust the spray angle to the blockage position, and increase the pressure and flow rate for precise unblocking.

[0074] This embodiment, through the synergistic effects of mixing, crushing, and flushing, and the coordination of three intelligent control modes, forms a complete anti-stagnant drainage solution, effectively addressing various drainage situations during construction in highly viscous strata. Engineering practice has verified that the slurry balance pipe jacking machine employing this embodiment's technical solution reduces the drainage rate and increases the monthly advance rate during construction in highly viscous strata, completely eliminating manual entry into the strata and achieving significant economic and social benefits.

[0075] All aspects not detailed in this invention are conventional technical means known to those skilled in the art.

[0076] The above content shows and describes the basic principles, main features, and beneficial effects of the present invention. The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A slurry discharge prevention structure, applied to a tunneling machine comprising a cutterhead, a shield, a conical crushing structure, and a slurry discharge pipe, characterized in that, The anti-stagnant structure includes: The mixing assembly is connected to the rotating part of the cutter head and is set in the rear mud chamber formed by the front partition and the rear partition of the shield body. The mixing area of ​​the mixing assembly completely or partially covers the opening of the discharge pipe. The central crushing assembly includes a cutterhead crushing block and a shield crushing block. The cutterhead crushing block is connected to the outer circumferential surface of the cutterhead rotating part, and the shield crushing block is connected to the inner ring surface of the shield front partition. The cutterhead crushing block and the shield side crushing block are arranged opposite to each other and form a toothed crushing gap. The high-pressure flushing assembly includes a high-pressure water pipeline connected to a high-pressure water nozzle, which is located at the bottom of a conical crushing structure. The spray direction of the high-pressure water nozzle includes the position of the screen holes in the conical crushing structure.

2. The anti-stagnant structure according to claim 1, characterized in that, The mixing assembly includes at least one mixing rod that extends radially along the rear mud and water chamber and is clearance-fitted with the rear side of the front partition of the shield and the front side of the rear partition of the shield.

3. The anti-stagnant structure according to claim 2, characterized in that, The stirring rod is provided with several overflow holes and / or reinforcing ribs.

4. The anti-stagnant structure according to any one of claims 1-3, characterized in that, The surfaces of the cutterhead crushing block and / or the shield crushing block and / or the stirring assembly are all provided with a wear-resistant layer.

5. The anti-stagnant structure according to claim 4, characterized in that, The high-pressure water nozzles are provided in several places, and each high-pressure water nozzle is distributed at intervals along the bottom of the conical crushing structure. The spray angle of the high-pressure water nozzles can be adjusted.

6. The anti-stagnant structure according to any one of claims 1-3 and 5, characterized in that, The high-pressure water pipeline is equipped with a pressure regulating valve and a flow regulating valve.

7. A tunneling machine, characterized in that, The device includes a cutterhead, a shield body, a main drive, a slurry discharge pipe, a conical crushing structure, and an anti-stagnant discharge structure as described in any one of claims 1-6. The shield body is internally divided into a front slurry chamber and a rear slurry chamber by a front partition and a rear partition. The main drive is fixed to the rear partition of the shield body. The cutterhead passes through the front slurry chamber and the rear slurry chamber in sequence and is connected to the main drive. The conical crushing structure is disposed in the front slurry chamber. The conical crushing structure and the crushing structure arranged on the torsion leg of the cutterhead form a shearing and crushing mechanism. The suction port of the slurry discharge pipe is located in the rear slurry chamber.

8. The tunneling machine according to claim 7, characterized in that, The rear partition of the shield body is provided with a stirring rod mounting hole one corresponding to the radial position of the stirring assembly, and the stirring rod mounting hole is connected to a sealing element; and / or the outer periphery of the shield body is provided with a stirring rod mounting hole two corresponding to the axial position of the stirring assembly, and the stirring rod mounting hole two is connected to a sealing element.

9. A tunneling machine control method, characterized in that, Applied to the tunneling machine of claim 7 or 8, the control method includes at least one of the following operating modes: Linkage control mode: Real-time acquisition of parameters such as main jacking force, cutterhead torque, mud discharge flow rate and mud specific gravity of the tunneling machine. When the main jacking force and / or cutterhead torque are detected to be rising continuously and the mud discharge flow rate is decreasing, the high-pressure flushing component is automatically started, and the flushing pressure and / or flushing angle and / or flushing flow rate are adjusted according to the parameter changes. Timed / interval operation mode: The high-pressure flushing component is automatically activated at preset time intervals for preventative flushing; Manual / Remote Control Mode: Receives manual control commands to control the start / stop and operating parameters of the high-pressure flushing component.

10. The tunneling machine control method according to claim 9, characterized in that, In the linkage control mode, when the cutter head torque exceeds 70% of the rated torque and lasts for more than 30 seconds, and the sludge discharge flow rate is less than 50% of the rated flow rate, the high-pressure flushing component is activated with an initial pressure of 10 MPa. If the parameters do not return to normal within 5 minutes, the pressure is increased to 15 MPa. In the timed / interval operation mode, the preset time interval is 10min-60min, and the flushing time is 30s-120s.

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