Mud cake prevention and control device and treatment method for ultra-large-diameter slurry shield cutter head in complex high-viscosity stratum

Abstract

The invention relates to the field of slurry shield cutterhead mud cake prevention and control devices, in particular to a complex high-viscosity stratum ultra-large-diameter slurry shield cutterhead mud cake prevention and control device and a treatment method. The complex high-viscosity stratum ultra-large-diameter slurry shield cutterhead mud cake prevention and control device comprises a cutterhead system, a high-pressure scouring injection system, a cutterhead gushing prevention sealing system, a power driving device and a background pressurization system; the cutterhead system, the high-pressure washing injection system, the cutterhead anti-gushing sealing system, the power driving device and the background pressurization system are sequentially connected from left to right. By adopting cutter layout optimization (the number of scrapers is increased by 20%-30%, and the central aperture ratio is 40%) and a high-pressure pulse jet technology (the impact force is 1.3 times of the conventional impact force, and the slurry flow is 90-360 L / min), and combining staged dynamic regulation (the stepping speed is 15-30 mm / min, and the pressure is 30-40 MPa), the mud cake cleaning efficiency is improved by more than 40%, and the mud cake cleaning efficiency is improved by more than 30%. And meanwhile, the service life of equipment is prolonged by more than 30% through an anti-wear design (the adhesion is reduced by 50% by the nano ceramic coating) and a drill rod strengthening structure (the compression strength of a double-layer pipe is + 25%, and the leakage rate is less than 0.1%).

Description

Technical Field

[0001] The present invention belongs to the field of mud cake prevention and control devices for a slurry shield cutter head, and specifically relates to a mud cake prevention and control device for a slurry shield cutter head with an ultra-large diameter in complex and high-viscosity formation and a treatment method. Background Art

[0002] In underground engineering construction, especially in the construction of ultra-large diameter slurry shields, when faced with complex and high-viscosity strata, problems such as blockage of the cutterhead and accumulation of mud cakes are often encountered. Especially in high-viscosity soil layers, the soil has strong adhesion, and mud cakes are easily accumulated at the front end of the cutterhead and continue to thicken, resulting in reduced working efficiency of the cutterhead and even causing the equipment to get stuck, affecting the entire shield construction process.

[0003] Traditional slurry shield machines mainly rely on the slurry circulation system of the shield system to control the transportation of soil particles. When ultra-large diameter slurry shields pass through high-viscosity strata, cutterhead mud cake adhesion is a core issue restricting construction efficiency and safety. Traditional technologies have low efficiency in cleaning mud cakes, conventional tool layouts have poor fluidity of slag, insufficient impact force of high-pressure flushing jets, long mud cake stripping cycles, and can easily cause a sharp increase in cutterhead torque, serious equipment loss, poor construction stability, and weak adaptability to working conditions, which need further improvement.

[0004] Therefore, a mud cake prevention and control device and treatment method for the cutter head of an ultra-large diameter slurry shield in complex and high-viscosity strata are proposed. The device has high mud cake cleaning efficiency, good soil fluidity in the cutter layout, sufficient impact force of the high-pressure flushing jet, short mud cake stripping cycle, no sharp increase in the torque of the cutter head, low equipment loss, strong construction stability, and good adaptability to working conditions. Summary of the invention

[0005] In order to overcome the core problem of cutterhead mud cake adhesion that restricts construction efficiency and safety when an ultra-large diameter slurry shield tunnel passes through high-viscosity strata, traditional technology has low efficiency in cleaning mud cakes, poor fluidity of conventional tool layout, insufficient impact force of high-pressure flushing jet, long mud cake stripping cycle, and easy to cause a sharp increase in cutterhead torque, serious equipment loss, poor construction stability, and weak adaptability to working conditions. Therefore, a cutterhead mud cake prevention and control device and treatment method for ultra-large diameter slurry shield tunneling in complex high-viscosity strata are proposed.

[0006] The technical solution of the present invention is: a device for preventing and controlling the cutter disc mud cake of an ultra-large diameter slurry shield in complex and high-viscosity strata, comprising a cutter disc system, a high-pressure flushing and jetting system, a cutter disc anti-surge sealing system, a power drive device and a backstage boosting system, wherein the cutter disc system, the high-pressure flushing and jetting system, the cutter disc anti-surge sealing system, the power drive device and the backstage boosting system are connected in sequence from left to right;

[0007] The cutter disc system includes a cutter disc, a center double-edged hob, a positive hob, a side hob, a wide cutter, an over-digging cutter, and a scraper. The cutter disc center opening rate is 40%, and the number of scrapers is increased by 20%-30% compared with the traditional layout. The blade height is 150mm and is symmetrically arranged.

[0008] The high-pressure flushing and jetting system includes a drill pipe, a nozzle, a check valve and a high-pressure jetting pipeline. The drill pipe is a double-layer pipe structure, the outer pipe is low-alloy steel, the inner pipe is corrosion-resistant alloy, and is constrained by a positioning sleeve. Each section of the drill pipe is 1.5m long and connected by a threaded casing, and a rubber ring is provided at the connection.

[0009] The knife disc anti-surge sealing system includes a shock-proof flange ball valve, a rotary knife gate valve, a double sleeve intermediate section and a sealing device. The sealing groove of the knife gate valve is a double-layer self-tightening sealing circular groove, the inner groove is in clearance with the gate plate, and the outer groove is in interference fit with the valve body;

[0010] The power drive device includes a front plate, a first rear plate, a second rear plate, a telescopic transmission rod and a transmission shaft. The first rear plate can be retracted into the second rear plate. The front plate and the rear plate are connected by the telescopic transmission rod. The power drive device is fixed to the main beam of the shield machine by bolts. The coaxiality error between the center axis of the front plate and the center axis of the cutter head is ≤±2mm.

[0011] Preferably, the background boosting system includes two high-pressure pumps, an air compressor and a control center. The maximum flushing pressure of the high-pressure pump is 40MPa, and the air compressor provides a compressed air pressure of 0.5-0.9MPa. The inner wall of the high-pressure injection pipeline is provided with a hydrophilic nano-coating and an external wireless pressure sensor, and the nozzle is a self-excited oscillation pulse jet nozzle.

[0012] Preferably, in the cutter disc system, the number of scrapers is increased by 20%-30% compared with the traditional layout, the blade height is 150mm and they are arranged symmetrically; 6 center double-edged hobs are installed in the center of the cutter disc, and their surfaces are coated with 0.1-0.3mm nano-ceramic coating; two super-digging knives are symmetrically arranged at the edge of the cutter disc, the positive hob is 170mm high and the blade spacing is 100mm, the wide cutting knife is 135mm high and the blade spacing is 150mm, and the side hob is located at the edge of the cutter disc.

[0013] Preferably, the drill pipe is a double-layer tube structure, the outer tube is low-alloy steel, the inner tube is corrosion-resistant alloy, each section of the drill pipe is long and connected by a threaded casing, and a rubber ring is provided at the connection; the inner wall of the high-pressure jet pipeline is provided with a hydrophilic nano-coating and an external wireless pressure sensor; the nozzle is a self-excited oscillation pulse jet nozzle, comprising a high-pressure jet inlet, an oscillation cavity, an impact wall and a pulse jet outlet.

[0014] Preferably, the valve stem of the knife gate valve is connected to the gate plate by a cross pin, and a rotating disc is provided on the top of the valve stem, and the rotating disc is fixed to the top of the valve stem by welding; the sealing groove is a double-layer self-tightening sealing circular groove, the inner groove of which is clearance-matched with the gate plate, and the outer groove is interference-fitted with the valve body; the sealing device comprises a pressure plate, a sleeve, aramid packing and a sealing rubber gasket, the inner diameter of the sleeve is clearance-matched with the outer tube of the drill pipe, and the aramid packing forms a radial seal after being tightened; the ball valve is a shockproof flange ball valve, which is connected to the opening position of the back panel of the knife disc by bolts, and a shockproof gasket is provided at the joint; the intermediate section is a double sleeve structure.

[0015] Preferably, the power drive device includes a front disk, a telescopic transmission rod, a support column and a transmission shaft, the front disk and the rear disk are connected by a telescopic transmission rod, the telescopic transmission rod is a steel hollow tube and the outer surface is coated with lubricating oil; the support column adjusts the inclination angle through a spherical rotating joint, and the transmission shaft is linked to the cylinder through a connecting slider; the cylinder is fixed inside the main body, and the groove on the back side thereof slides with the connecting slider, and the transmission shaft is embedded in the guide rail on the inner wall of the main body through a slide groove to realize axial movement; the lifting plate adjusts the height by rotating the lead screw, and a pulley is provided at the bottom, and a displacement sensor is attached to the surface of the front disk, and the transmission shaft of the power drive device is linked to the transmission assembly through gears, and the transmission assembly is a transmission ring structure for driving the opening and closing of the clamping claw; the displacement sensor is a wireless sensor, which monitors the displacement accuracy of the drill rod in real time, and the transmission assembly is an annular gear ring, and the gear meshes with it and drives the clamping claw through a connecting rod to open and close at an angle of 0°-90°.

[0016] Preferably, a groove is provided on the back of the cylinder for connecting the sliding block; the power drive device also includes a power meter, a silencer, a first motor, a second motor and a lighting lamp; the first motor drives the telescopic transmission rod through a coupling, and the second motor is connected to the connecting slider through a pulley. The lifting plate of the power drive device adjusts the height by rotating the screw, and a pulley is provided at the bottom.

[0017] As a preference, the maximum flushing pressure of the high-pressure pump of the background booster system is 40MPa, the air compressor provides a compressed air pressure of 0.5-0.9MPa, the mud flow rate is 90-360L / min and the specific gravity is ≤1.2g / cm 3 The control center receives data from the wireless pressure sensor and displacement sensor in real time, and dynamically adjusts the pressure fluctuation range of the high-pressure pump to within ±5%. The control center is connected to the wireless pressure sensor and displacement sensor through the RS485 communication protocol, and outputs PWM signals to adjust the speed of the high-pressure pump motor and the opening of the air compressor valve.

[0018] The present invention also provides a method for controlling a mud cake prevention and control device for a cutter head of an ultra-large diameter slurry shield in a complex and high-viscosity stratum, which comprises the above-mentioned device for controlling a mud cake prevention and control device for a cutter head of an ultra-large diameter slurry shield in a complex and high-viscosity stratum, and the control method is as follows:

[0019] Step 1: Set up a platform at the center of the cutter head and install the drilling rig, and test the sealing performance of the aramid packing of the sealing device by pressurizing it to 0.5MPa for 5 minutes;

[0020] Step 2: Install a shockproof flange ball valve at the opening position of the back panel of the cutter disc, use a torque wrench to tighten the bolts to the preset torque, and install a shockproof gasket at the joint between the ball valve and the cutter disc;

[0021] Step 3: connect the shockproof flange ball valve to the rotary knife gate valve through the connecting flange, the valve stem of the knife gate valve is connected to the gate plate through a transverse pin, and a rotating disc is provided on the top of the valve stem; the knife gate valve is connected to the sealing device through a double sleeve intermediate section, and a sealing rubber gasket is arranged between the pressure plate and the sleeve of the sealing device and tightened by bolts;

[0022] Step 4: Use a laser rangefinder to adjust the front disc position of the power drive device so that the deviation between the center of the drill rod and the center of the sealing device is ≤±1mm, and the transmission shaft is linked to the transmission assembly of the transmission ring structure through the gear;

[0023] Step 5: Evenly wrap the aramid packing around the high-pressure flushing hole and press it tightly to prevent blockage between the outer and inner tubes when the drill pipe is inserted;

[0024] Step 6: Install the first section of drill pipe to a certain distance from the gate valve, close the gate valve to prevent backflow, and the drill pipe is connected by a threaded casing and a rubber ring is provided at the connection;

[0025] Step 7: When opening the ball valve and gate valve, listen for abnormal noise in the pipeline and check for leakage in the connecting flange. Leakage points should be treated by replacing the sealing rubber gasket or re-tightening the bolts;

[0026] Step 8: Use the total station to position the drill rig, align the drill rod with the center of the mud cake, with a positioning error of ≤±2mm, and calibrate in real time through the displacement sensor;

[0027] Step 9: Move the drill pipe forward to the rear partition of the cutter head at a certain speed, turn on the high-pressure pump and air compressor for test flushing, and set the initial compressed air pressure to 0.6-0.8MPa and the mud flow rate to 90-360L / min;

[0028] Step 10: Control parameters in stages according to mud cake thickness: when mud cake thickness is greater than 100mm, the stepping speed is within a certain range, the mud pressure is 35-40MPa, and the compressed air pressure is 0.6-0.8MPa; when thickness is less than 100mm, the stepping speed is within another range, the mud pressure is 30-35MPa; when residual thickness is less than 5mm, the stepping speed is within another range, the mud pressure is 30-40MPa;

[0029] Step 11: Use a laser coaxiality meter to re-measure the coaxiality of the drill pipe every time a certain distance is drilled. The deviation should be ≤±0.5mm. If the sealing device leaks, re-tighten the pressure plate and increase the torque by a certain percentage.

[0030] Step 12: When connecting the drill pipe, the interruption time is controlled within a certain range, the threaded casing is connected at a certain speed, and the hydrophilic nano-coating on the inner wall of the high-pressure jet pipeline is kept clean;

[0031] Step 13: Retract the drill pipe at a certain speed. When the drill bit is retracted to the sealing device, close the ball valve and the gate valve, and adjust the pressure fluctuation of the high-pressure pump to within ±5% through the control center;

[0032] Step 14: Use a special rod pulling tool to horizontally remove the drill rod. When removing the sealing device, protect the sealing surface of the aramid packing and perform pre-maintenance on the sealing rubber gasket.

[0033] Step 15: Rotate the cutter disc to the next cleaning point at a certain speed, adjust the inclination of the support column through the spherical rotating joint of the power drive device, and repeat steps 1 to 14 for cyclic cleaning;

[0034] Step 16: When removing the flushing device, record the wear status of the claws, gears and transmission components, and replace the sealing rubber gasket;

[0035] Step 17: Clean the site and check that the thickness of the residual mud cake on the surface of the cutter disc is less than 5mm.

[0036] Beneficial effects of the present invention: The present invention significantly improves the effectiveness of preventing and controlling mud cakes from the cutterhead of a shield machine in high-viscosity strata through systematic technical integration and intelligent control:

[0037] First, the optimization of tool layout (the number of scrapers increased by 20%-30%, the center opening rate was 40%) and high-pressure pulse jet technology (impact force reached 1.3 times of conventional, mud flow rate 90-360L / min), combined with phased dynamic control (step speed 15-30mm / min, pressure 30-40MPa), increased the mud cake cleaning efficiency by more than 40%. At the same time, through anti-wear design (nano-ceramic coating reduces adhesion by 50%) and drill pipe strengthening structure (double-layer pipe compressive strength +25%, leakage rate <0.1%), the equipment life was extended by more than 30%;

[0038] Second, integrated vibration suppression (shockproof ball valve + double casing reduces vibration by 60%), precision calibration (laser ranging ±0.5mm) and intelligent emergency response (pressure fluctuation control ±5%, seal repair 5-second response) ensure safe and stable construction, and rely on the rapid connection of segmented drill pipes (interruption time is halved) and green drive (carbon emissions are reduced by 35%) to achieve a double reduction of more than 20% in energy consumption and maintenance costs;

[0039] Thirdly, based on the quantitative classification of working conditions (propulsion speed reduced by 30%-50%, cutter disc torque increased by 20%-150%) and differentiated solutions, the heavy mud cake adopts the "manual crushing + 50MPa ultra-high pressure flushing" combined process, combined with full-process wireless sensor monitoring and standardized operations (17-step quantitative indicators), which improves the adaptability to complex working conditions and construction consistency by 80% respectively, and ultimately achieves a high-standard cleaning effect with mud cake residue of less than 5mm. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of a method for ultra-high pressure washing of the central mud cake of a pressure cutter disc in one embodiment of the present invention;

[0041] Figure 2 A high-pressure flushing injection system in an embodiment of the present invention;

[0042] Figure 3 is a schematic diagram of a nozzle in one embodiment of the present invention;

[0043] Figure 4 A side view of a cutter head anti-surge sealing system in one embodiment of the present invention;

[0044] Figure 5 It is a front view of a cutter head anti-surge sealing system in one embodiment of the present invention;

[0045] Figure 6 is a schematic diagram of a cutter disc in one embodiment of the present invention;

[0046] Figure 7 is a schematic diagram of a sealing device in an example of the present invention;

[0047] Figure 8 A side view of a pressure plate of a sealing device in an example of the present invention;

[0048] Fig. 9 A side view of a sealing device sleeve in an example of the present invention;

[0049] Fig.10 A schematic diagram of a wear-resistant alloy layer of a center tool in an example of the present invention;

[0050] Fig.11 It is a front view of a drill pipe in an example of the present invention;

[0051] Fig.12is a schematic diagram of a power driving device in an example of the present invention;

[0052] Fig.13 A schematic diagram of a background pressurization system in an example of the present invention;

[0053] Fig.14 It is a work flow chart of the present invention;

[0054] Fig.15 A schematic diagram of a knife gate valve in an example of the present invention;

[0055] Fig.16 It is a schematic diagram of the interior of the front and rear discs in one embodiment of the present invention;

[0056] Fig.17 is a cross-sectional view of a high-pressure injection pipeline in an example of the present invention;

[0057] Fig.18 is a schematic diagram of a shock-absorbing gasket in an example of the present invention;

[0058] Fig.19 It is a schematic diagram of a threaded sleeve in an example of the present invention.

[0059] The marks in the attached drawings are: 1. Cutterhead system; 101. Center double-edged hob; 102. Positive hob; 103. Side hob; 104. Wide cutter; 105. Super digging knife; 106. Scraper; 107. Cutterhead; 2. High-pressure flushing and injection system; 3. Cutterhead anti-surge sealing system; 3-1-1. Shockproof gasket; 301. Valve body; 302. Cavity; 303. Valve stem; 304. Rotating disc; 305. Sealing groove; 306. Cross pin; 307. Gate; 308 , connecting flange; 4, power drive device; 4-1, front plate; 4-2, telescopic transmission rod; 4-3, first rear plate; 4-4, second rear plate; 4-5, support column; 4-6, transmission shaft; 4-7, main body; 4-8, cylinder; 4-9, power meter; 4-10, second motor; 4-11, lighting lamp; 4-12, lifting plate; 4-13, handle; 4-14, silencer; 4-15, first motor; 4-16, rotating screw; 4-17, spherical rotating joint; 4-18, slide; 4-19, connecting slider; 4-20, groove; 4-21, displacement sensor; 4-22, joystick; 4-23, pulley; 5, backstage booster system; 5-1, high pressure pump; 5-2, air compressor; 5-3, control center; 2-1, nozzle; 3-1, ball valve; 3-2, gate valve; 3-3, intermediate section; 3-4, sealing device; 2-2, drill pipe; 2-2-1, outer tube; 2-2-2, inner tube; 2-2-3, Positioning sleeve; 401, claw; 402, gear; 403, transmission assembly; 2-3, check valve; 2-4, high-pressure injection pipeline; 2-4-1, hydrophilic nano-coating; 2-4-2, wireless pressure sensor; 201, high-pressure jet inlet; 202, oscillation chamber; 203, impact wall; 204, pulse jet outlet; 601, pressure plate; 602, sleeve; 603, aramid packing; 604, sealing rubber gasket; 7-1, threaded sleeve; 7-2, rubber ring. DETAILED DESCRIPTION

[0060] The present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0061] See also Figure 1-Figure 19 The present invention provides an embodiment: a device for preventing and controlling mud cakes from a cutter head of an ultra-large diameter slurry shield in a complex and high-viscosity formation, comprising a cutter head system 1, a high-pressure flushing and jetting system 2, a cutter head anti-surge sealing system 3, a power drive device 4 and a backstage boosting system 5, wherein the cutter head system 1, the high-pressure flushing and jetting system 2, the cutter head anti-surge sealing system 3, the power drive device 4 and the backstage boosting system 5 are connected in sequence from left to right;

[0062] The cutter disc system 1 includes a cutter disc 107, a center double-edged hob 101, a positive hob 102, a side hob 103, a wide cutter 104, an over-digging cutter 105, and a scraper 106. The center opening rate of the cutter disc 107 is 40%, and the number of scrapers 106 is increased by 20%-30% compared with the traditional layout. The blade height is 150mm and is symmetrically arranged.

[0063] The high-pressure flushing and jetting system 2 includes a drill pipe 2-2, a nozzle 2-1, a check valve 2-3 and a high-pressure jetting pipeline 2-4. The drill pipe 2-2 is a double-layer pipe structure. The outer pipe 2-2-1 is low-alloy steel, and the inner pipe 2-2-2 is corrosion-resistant alloy. It is constrained by a positioning sleeve 2-2-3. Each section of the drill pipe 2-2 is 1.5m long and connected by a threaded casing 7-1. A rubber ring 7-2 is provided at the connection.

[0064] The knife disc anti-surge sealing system 3 includes a shockproof flange ball valve 3-1, a rotary knife gate valve 3-2, a double sleeve intermediate section 3-3 and a sealing device 3-4. The sealing groove 305 of the knife gate valve 3-2 is a double-layer self-tightening sealing circular groove, the inner groove and the gate plate 307 have a clearance fit, and the outer groove and the valve body 301 have an interference fit;

[0065] The power drive device 4 includes a front disc 4-1, a first rear disc 4-3, a second rear disc 4-4, a telescopic transmission rod 4-2 and a transmission shaft 4-6. The first rear disc 4-3 can be retracted into the second rear disc 4-4. The front disc 4-1 and the rear disc are connected by the telescopic transmission rod 4-2. The power drive device 4 is fixed to the main beam of the shield machine by bolts. The coaxiality error between the center axis of the front disc 4-1 and the center axis of the cutter disc 107 is ≤±2mm.

[0066] See also Figure 1 and Fig.13 In this embodiment, the backstage boosting system 5 includes two high-pressure pumps 5-1, an air compressor 5-2 and a control center 5-3. The maximum flushing pressure of the high-pressure pump 5-1 is 40MPa, and the air compressor 5-2 provides a compressed air pressure of 0.5-0.9MPa; wherein, the inner wall of the high-pressure injection pipeline 2-4 is provided with a hydrophilic nano-coating 2-4-1 and an external wireless pressure sensor 2-4-2, and the nozzle 2-1 is a self-excited oscillation pulse jet nozzle.

[0067] See also Figure 1 and Figure 6 In this embodiment, in the cutter disc system 1, the number of scrapers 106 is increased by 20%-30% compared with the traditional layout, the blade height is 150mm and they are arranged symmetrically; 6 center double-edged hobs 101 are installed in the center of the cutter disc 107, and their surfaces are coated with 0.1-0.3mm nano-ceramic coating; two super digging knives 105 are symmetrically arranged at the edge of the cutter disc 107, the positive hob 102 is 170mm high and the blade spacing is 100mm, the wide cutting knife 104 is 135mm high and the blade spacing is 150mm, and the side hob 103 is located at the edge of the cutter disc 107.

[0068] See also Figure 1-Figure 3 and Fig.19 In this embodiment, the drill pipe 2-2 is a double-layer tube structure, the outer tube 2-2-1 is low alloy steel, the inner tube 2-2-2 is corrosion-resistant alloy, each section of the drill pipe 2-2 is 1.5m long and connected by a threaded casing 7-1, and a rubber ring 7-2 is provided at the connection; the inner wall of the high-pressure jet pipeline 2-4 is provided with a hydrophilic nano-coating 2-4-1 and an external wireless pressure sensor 2-4-2; the nozzle 2-1 is a self-excited oscillation pulse jet nozzle, comprising a high-pressure jet inlet 201, an oscillation cavity 202, an impact wall 203 and a pulse jet outlet 204.

[0069] See also Figure 1 , Figure 4 , Figure 5 and Fig.18 In this embodiment, the valve stem 303 of the knife gate valve 3-2 is connected to the gate plate 307 through a cross pin 306, and a rotating disc 304 is provided on the top of the valve stem 303, and the rotating disc 304 is fixed to the top of the valve stem 303 by welding; the sealing groove 305 is a double-layer self-tightening sealing circular groove, the inner groove of which is clearance-matched with the gate plate 307, and the outer groove is interference-fitted with the valve body 301; the sealing device 3-4 includes a pressure plate 601, a sleeve 602, an aramid packing 603 and a sealing rubber gasket 604, the inner diameter of the sleeve 602 is clearance-matched with the outer tube 2-2-1 of the drill pipe 2-2, and the aramid packing 603 forms a radial seal after being compressed, the ball valve 3-1 is a shockproof flange ball valve, which is connected to the opening position of the back panel of the knife disc 107 by bolts, and a shockproof gasket 3-1-1 is provided at the joint; the intermediate section 3-3 is a double sleeve structure.

[0070] See also Figure 1 , Fig.12 and Fig.16In this embodiment, the power drive device 4 includes a front disc 4-1, a telescopic transmission rod 4-2, a support column 4-5 and a transmission shaft 4-6. The front disc 4-1 is connected to the rear disc through the telescopic transmission rod 4-2. The telescopic transmission rod 4-2 is a steel hollow tube and the outer surface is coated with lubricating oil; the support column 4-5 adjusts the inclination angle through a spherical rotary joint 4-17, and the transmission shaft 4-6 is linked to the cylinder 4-8 through a connecting slider 4-19; the cylinder 4-8 is fixed inside the main body 4-7, and its back groove 4-20 is slidably matched with the connecting slider 4-19, and the transmission shaft 4-6 is embedded in the main body 4-7 through the slide groove 4-18 The wall guide rail realizes axial movement; the lifting plate 4-12 adjusts the height by rotating the screw 4-16, and a pulley 4-23 is provided at the bottom. The displacement sensor 4-21 is attached to the surface of the front disk 4-1. The transmission shaft 4-6 of the power drive device 4 is linked with the transmission component 403 through the gear 402. The transmission component 403 is a transmission ring structure for driving the opening and closing of the claw 401; the displacement sensor 4-21 is a wireless sensor for real-time monitoring of the displacement accuracy of the drill rod 2-2. The transmission component 403 is an annular gear ring, and the gear 402 is meshed with it and drives the opening and closing angle of the claw 401 through the connecting rod to be 0°-90°.

[0071] See also Figure 1 and Fig.12 In this embodiment, a groove 4-20 is provided on the back of the cylinder 4-8 for connecting the slider 4-19 for sliding; the power drive device 4 also includes a power meter 4-9, a silencer 4-14, a first motor 4-15, a second motor 4-10 and a lighting lamp 4-11; the first motor 4-15 drives the telescopic transmission rod 4-2 through a coupling, and the second motor 4-10 is connected to the connecting slider 4-19 through a pulley. The lifting plate 4-12 of the power drive device 4 is adjusted in height by rotating the screw 4-16, and a pulley 4-23 is provided at the bottom.

[0072] See also Figure 1 , Fig.12 and Fig.13 In this embodiment, the maximum flushing pressure of the high-pressure pump 5-1 of the backstage booster system 5 is 40MPa, the air compressor 5-2 provides a compressed air pressure of 0.5-0.9MPa, the mud flow rate is 90-360L / min and the specific gravity is ≤1.2g / cm 3 The control center 5-3 receives the data of the wireless pressure sensor 2-4-2 and the displacement sensor 4-21 in real time, and dynamically adjusts the pressure fluctuation range of the high-pressure pump 5-1 to within ±5%. The control center 5-3 is connected to the wireless pressure sensor 2-4-2 and the displacement sensor 4-21 through the RS485 communication protocol, and outputs PWM signals to adjust the motor speed of the high-pressure pump 5-1 and the valve opening of the air compressor 5-2.

[0073] The present invention also provides a method for controlling a mud cake prevention and control device for a cutter head of an ultra-large diameter slurry shield in a complex and high-viscosity stratum, which includes the above-mentioned device for controlling a mud cake prevention and control device for a cutter head of an ultra-large diameter slurry shield in a complex and high-viscosity stratum, and the control method is as follows:

[0074] Step 1: Set up a platform at the central rotating body of the cutter head 107 and install a drilling rig, and perform a sealing test on the aramid packing 603 of the sealing device 3-4 by pressurizing it to 0.5 MPa for 5 minutes;

[0075] Step 2: Install a shockproof flange ball valve 3-1 at the opening position of the back panel of the cutter head 107, use a torque wrench to tighten the bolts according to the preset torque, and set a shockproof gasket 3-1-1 at the joint between the ball valve 3-1 and the cutter head 107;

[0076] Step 3: Connect the shockproof flange ball valve 3-1 to the rotary knife gate valve 3-2 through the connecting flange 308. The valve stem 303 of the knife gate valve 3-2 is connected to the gate plate 307 through the cross pin 306. The top of the valve stem 303 is provided with a rotating disc 304. The knife gate valve 3-2 is connected to the sealing device 3-4 through the double sleeve intermediate section 3-3. A sealing rubber gasket 604 is arranged between the pressure plate 601 and the sleeve 602 of the sealing device 3-4 and tightened by bolts.

[0077] Step 4: Use a laser rangefinder to adjust the position of the front plate 4-1 of the power drive device 4 so that the deviation between the center of the drill rod 2-2 and the center of the sealing device 3-4 is ≤±1mm, and the transmission shaft 4-6 is linked to the transmission assembly 403 of the transmission ring structure through the gear 402;

[0078] Step 5: Evenly wrap the aramid packing 603 around the high-pressure flushing hole and press it tightly to prevent the outer tube 2-2-1 and the inner tube 2-2-2 from being blocked when the drill rod 2-2 is inserted;

[0079] Step 6: Install the first section of drill pipe 2-2 to 3-4 cm from the gate valve 3-2, close the gate valve 3-2 to prevent backflow, and connect the drill pipe 2-2 through the threaded casing 7-1 and a rubber ring 7-2 is provided at the connection;

[0080] Step 7: When opening the ball valve 3-1 and the gate valve 3-2, listen for abnormal noise in the pipeline and check for leakage in the connecting flange 308. The leakage point can be treated by replacing the sealing rubber gasket 604 or re-tightening the bolts;

[0081] Step 8: Use the total station to position the drill rig, align the drill rod 2-2 with the center of the mud cake, and the positioning error is ≤±2mm, and calibrate in real time through the displacement sensor 4-21;

[0082] Step 9: Move the drill rod 2-2 forward to the rear partition of the cutter head at a speed of 100 mm / min, start the high-pressure pump 5-1 and the air compressor 5-2 for test flushing, and set the initial compressed air pressure to 0.6-0.8 MPa and the mud flow rate to 90-360 L / min;

[0083] Step 10: Control parameters in stages according to mud cake thickness: when mud cake thickness is >100mm, step speed is 15-20mm / min, mud pressure is 35-40MPa, and compressed air pressure is 0.6-0.8MPa; when thickness is ≤100mm, step speed is 25-30mm / min, mud pressure is 30-35MPa; when residual thickness is <5mm, step speed is 10-15mm / min, mud pressure is 30-40MPa;

[0084] Step 11: Use a laser coaxiality meter to re-measure the coaxiality of the drill pipe 2-2 every 50cm of drilling, and the deviation should be ≤±0.5mm. If the sealing device 3-4 leaks, re-tighten the pressure plate 601 and increase the torque by 10%-15%;

[0085] Step 12: When connecting the drill pipe 2-2, the interruption time is controlled within 3-5 minutes, the threaded casing 7-1 is connected with a jacking speed of 25 mm / min, and the hydrophilic nano-coating 2-4-1 on the inner wall of the high-pressure jetting pipeline 2-4 is kept clean;

[0086] Step 13: Retract the drill rod 2-2 at a speed of 30 mm / min. When the drill bit is retracted to the sealing device 3-4, close the ball valve 3-1 and the gate valve 3-2, and adjust the pressure fluctuation of the high-pressure pump 5-1 to within ±5% through the control center 5-3;

[0087] Step 14: Use a special rod pulling tool to horizontally remove the drill rod 2-2, protect the sealing surface of the aramid packing 603 when removing the sealing device 3-4, and perform pre-maintenance on the sealing rubber gasket 604;

[0088] Step 15: Rotate the blade disc 107 to the next cleaning point at 0.5-1 rpm, adjust the inclination angle of the support column 4-5 through the spherical rotating joint 4-17 of the power drive device 4, and repeat steps 1 to 14 for cyclic cleaning;

[0089] Step 16: When removing the flushing device, record the wear status of the claw 401, the gear 402 and the transmission assembly 403, and replace the sealing rubber gasket 604;

[0090] Step 17: Clean the site and check that the thickness of the residual mud cake on the surface of the cutter head 107 is less than 5 mm.

[0091] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of those skilled in the art without departing from the spirit of the present invention.

Claims

1. A device for preventing and controlling mud cakes from a cutterhead of an ultra-large diameter slurry shield machine in complex and high-viscosity strata, comprising a cutterhead system (1), a high-pressure flushing and jetting system (2), a cutterhead anti-surge sealing system (3), a power drive device (4) and a backstage boosting system (5), characterized in that: The cutter disc system (1), the high-pressure flushing and jetting system (2), the cutter disc anti-surge sealing system (3), the power drive device (4) and the backstage boosting system (5) are connected in sequence from left to right; The cutter disc system (1) comprises a cutter disc (107), a center double-edged hob (101), a positive hob (102), a side hob (103), a wide cutter (104), an over-digging cutter (105), and a scraper (106). The center opening rate of the cutter disc (107) is 40%, the number of scrapers (106) is increased by 20%-30% compared with the traditional layout, the height of the cutter is 150 mm and they are arranged symmetrically. The high-pressure flushing and jetting system (2) comprises a drill rod (2-2), a nozzle (2-1), a check valve (2-3) and a high-pressure jetting pipeline (2-4); the drill rod (2-2) is a double-layer tube structure, the outer tube (2-2-1) is made of low alloy steel, the inner tube (2-2-2) is made of corrosion-resistant alloy, and is restrained by a positioning sleeve (2-2-3); each section of the drill rod (2-2) is 1.5 m long and is connected by a threaded casing (7-1), and a rubber ring (7-2) is provided at the connection; The knife disc anti-surge sealing system (3) comprises a shockproof flange ball valve (3-1), a rotary knife gate valve (3-2), a double sleeve intermediate section (3-3) and a sealing device (3-4), wherein the sealing groove (305) of the knife gate valve (3-2) is a double-layer self-tightening sealing circular groove, wherein the inner groove and the gate plate (307) are clearance-fitted, and the outer groove and the valve body (301) are interference-fitted; The power drive device (4) comprises a front disc (4-1), a first rear disc (4-3), a second rear disc (4-4), a telescopic transmission rod (4-2) and a transmission shaft (4-6); the first rear disc (4-3) can be retracted into the second rear disc (4-4); the front disc (4-1) and the rear disc are connected via the telescopic transmission rod (4-2); the power drive device (4) is fixed to the main beam of the shield machine via bolts; the coaxiality error between the central axis of the front disc (4-1) and the central axis of the cutter disc (107) is ≤±2mm.

2. According to claim 1, a device for preventing and controlling mud cakes from the cutter head of a super-large diameter slurry shield machine in complex and high-viscosity strata, characterized in that: The backstage boosting system (5) comprises two high-pressure pumps (5-1), an air compressor (5-2) and a control center (5-3), wherein the maximum flushing pressure of the high-pressure pump (5-1) is 40 MPa, and the air compressor (5-2) provides a compressed air pressure of 0.5-0.9 MPa; wherein the inner wall of the high-pressure injection pipeline (2-4) is provided with a hydrophilic nano-coating (2-4-1) and an external wireless pressure sensor (2-4-2), and the nozzle (2-1) is a self-excited oscillation pulse jet nozzle.

3. The device for preventing and controlling mud cakes from cutter heads of large diameter slurry shield machines in complex and high-viscosity formations according to claim 1 is characterized by: In the cutter disc system (1), the number of scrapers (106) is increased by 20%-30% compared with the traditional layout, the blade height is 150 mm and they are arranged symmetrically; six central double-edged rollers (101) are installed in the center of the cutter disc (107), and the surfaces of the central double-edged rollers (101) are coated with a 0.1-0.3 mm nano-ceramic coating; two super-digging blades (105) are symmetrically arranged at the edge of the cutter disc (107), the positive roller (102) has a blade height of 170 mm and a blade spacing of 100 mm, the wide cutting blade (104) has a blade height of 135 mm and a blade spacing of 150 mm, and the side roller (103) is located at the edge of the cutter disc (107).

4. The device for preventing and controlling mud cakes from cutter heads of large diameter slurry shield machines in complex and high-viscosity formations according to claim 1 is characterized by: The drill pipe (2-2) is a double-layer tube structure, the outer tube (2-2-1) is low alloy steel, and the inner tube (2-2-2) is corrosion-resistant alloy. Each section of the drill pipe (2-2) is 1.5 m long and connected by a threaded sleeve (7-1), and a rubber ring (7-2) is provided at the connection. The inner wall of the high-pressure jet pipeline (2-4) is provided with a hydrophilic nano coating (2-4-1) and an external wireless pressure sensor (2-4-2). The nozzle (2-1) is a self-excited oscillation pulse jet nozzle, comprising a high-pressure jet inlet (201), an oscillation cavity (202), an impact wall (203) and a pulse jet outlet (204).

5. The device for preventing and controlling mud cakes from cutter heads of large diameter slurry shield machines in complex and high-viscosity formations according to claim 1 is characterized by: The valve stem (303) of the knife gate valve (3-2) is connected to the gate plate (307) via a transverse pin (306); a rotating disc (304) is provided on the top of the valve stem (303); the rotating disc (304) is fixed to the top of the valve stem (303) by welding; the sealing groove (305) is a double-layer self-tightening sealing circular groove, the inner groove of which is clearance-matched with the gate plate (307), and the outer groove of which is interference-matched with the valve body (301); the sealing device (3-4) comprises a pressure plate (601) , a sleeve (602), an aramid packing (603) and a sealing rubber gasket (604); the inner diameter of the sleeve (602) is in clearance with the outer tube (2-2-1) of the drill pipe (2-2); the aramid packing (603) is compressed to form a radial seal; the ball valve (3-1) is a shockproof flange ball valve, which is connected to the opening position of the back panel of the cutter head (107) by bolts, and a shockproof gasket (3-1-1) is arranged at the joint; the intermediate section (3-3) is a double sleeve structure.

6. The device for preventing and controlling mud cakes from cutter heads of large diameter slurry shield machines in complex and high-viscosity formations according to claim 1 is characterized by: The power drive device (4) comprises a front disc (4-1), a telescopic transmission rod (4-2), a support column (4-5) and a transmission shaft (4-6); the front disc (4-1) is connected to the rear disc via the telescopic transmission rod (4-2); the telescopic transmission rod (4-2) is a steel hollow tube and the outer surface of which is coated with lubricating oil; the support column (4-5) is used to adjust the inclination angle via a spherical rotary joint (4-17); the transmission shaft (4-6) is linked to the cylinder (4-8) via a connecting slider (4-19); the cylinder (4-8) is fixed inside the main body (4-7); the back groove (4-20) thereof is slidably matched with the connecting slider (4-19); the transmission shaft (4-6) is embedded in the inner wall of the main body (4-7) via a sliding groove (4-18). The guide rail is used to realize axial movement; the height of the lifting plate (4-12) is adjusted by rotating the lead screw (4-16), and a pulley (4-23) is provided at the bottom; the displacement sensor (4-21) is attached to the surface of the front plate (4-1); the transmission shaft (4-6) of the power drive device (4) is linked with the transmission component (403) through the gear (402); the transmission component (403) is a transmission ring structure, which is used to drive the opening and closing of the clamping claw (401); the displacement sensor (4-21) is a wireless sensor, which monitors the displacement accuracy of the drill rod (2-2) in real time; the transmission component (403) is an annular gear ring, the gear (402) is meshed with it and drives the opening and closing angle of the clamping claw (401) through the connecting rod to be 0°-90°.

7. The device for preventing and controlling mud cakes from cutter heads of super-large diameter slurry shield machines in complex and high-viscosity formations according to claim 6 is characterized by: The back of the cylinder (4-8) is provided with a groove (4-20) for connecting the slider (4-19) to slide; the power drive device (4) also includes a power meter (4-9), a silencer (4-14), a first motor (4-15), a second motor (4-10) and a lighting lamp (4-11); the first motor (4-15) drives the telescopic transmission rod (4-2) through a coupling, and the second motor (4-10) is connected to the connecting slider (4-19) through a pulley; the lifting plate (4-12) of the power drive device (4) is adjusted in height by rotating a lead screw (4-16), and a pulley (4-23) is provided at the bottom.

8. The device for preventing and controlling mud cakes from cutter heads of large diameter slurry shield machines in complex and high-viscosity formations according to claim 1 is characterized by: The maximum flushing pressure of the high-pressure pump (5-1) of the backstage boosting system (5) is 40MPa, the air compressor (5-2) provides a compressed air pressure of 0.5-0.9MPa, the mud flow rate is 90-360L / min and the specific gravity is ≤1.2g / cm 3 The control center (5-3) receives data from the wireless pressure sensor (2-4-2) and the displacement sensor (4-21) in real time, and dynamically adjusts the pressure fluctuation range of the high-pressure pump (5-1) to within ±5%. The control center (5-3) is connected to the wireless pressure sensor (2-4-2) and the displacement sensor (4-21) through the RS485 communication protocol, and outputs a PWM signal to adjust the motor speed of the high-pressure pump (5-1) and the valve opening of the air compressor (5-2).

9. A method for controlling mud cakes in a large diameter slurry shield cutterhead in complex high-viscosity strata, characterized in that It comprises a device for preventing and controlling mud cakes from a cutter head of an ultra-large diameter slurry shield machine in complex and high-viscosity strata according to any one of claims 1 to 8, and the treatment method thereof is as follows: Step 1: Set up a platform at the central rotating body of the cutter head (107) and install a drilling rig, and perform a sealing test on the aramid packing (603) of the sealing device (3-4) by pressurizing it to 0.5 MPa for 5 minutes; Step 2: Install a shockproof flange ball valve (3-1) at the opening position of the back panel of the cutter disc (107), use a torque wrench to tighten the bolts according to the preset torque, and set a shockproof gasket (3-1-1) at the junction of the ball valve (3-1) and the cutter disc (107); Step 3: The shockproof flange ball valve (3-1) is connected to the rotary knife gate valve (3-2) through the connecting flange (308); the valve stem (303) of the knife gate valve (3-2) is connected to the gate plate (307) through the cross pin (306); a rotating disc (304) is provided on the top of the valve stem (303); the knife gate valve (3-2) is connected to the sealing device (3-4) through the double sleeve intermediate section (3-3); a sealing rubber gasket (604) is arranged between the pressure plate (601) and the sleeve (602) of the sealing device (3-4) and is tightened by bolts; Step 4: adjusting the position of the front disk (4-1) of the power drive device (4) by means of a laser rangefinder so that the deviation between the center of the drill rod (2-2) and the center of the sealing device (3-4) is ≤±1 mm, and the transmission shaft (4-6) is linked to the transmission assembly (403) of the transmission ring structure through the gear (402); Step 5: Evenly wrap the aramid packing (603) around the high-pressure flushing hole and press it tightly to prevent the outer tube (2-2-1) and the inner tube (2-2-2) from being blocked when the drill rod (2-2) is inserted; Step 6: Install the first section of drill pipe (2-2) to a distance of 3-4 cm from the gate valve (3-2), close the gate valve (3-2) to prevent backflow, and the drill pipe (2-2) is connected via a threaded sleeve (7-1) and a rubber ring (7-2) is provided at the connection; Step 7: When opening the ball valve (3-1) and the gate valve (3-2), listen for abnormal noise in the pipeline and check for leakage in the connecting flange (308). If leakage occurs, replace the sealing rubber gasket (604) or tighten the bolts again. Step 8: Use a total station to position the drill rig so that the drill rod (2-2) is aligned with the center of the mud cake, with a positioning error of ≤±2mm, and calibrate in real time through a displacement sensor (4-21); Step 9: Move the drill rod (2-2) forward to the rear partition of the cutter head at a speed of 100 mm / min, start the high-pressure pump (5-1) and the air compressor (5-2) for test flushing, and set the initial compressed air pressure to 0.6-0.8 MPa and the mud flow rate to 90-360 L / min; Step 10: Control parameters in stages according to mud cake thickness: when mud cake thickness is >100mm, step speed is 15-20mm / min, mud pressure is 35-40MPa, and compressed air pressure is 0.6-0.8MPa; when thickness is ≤100mm, step speed is 25-30mm / min, mud pressure is 30-35MPa; when residual thickness is <5mm, step speed is 10-15mm / min, mud pressure is 30-40MPa; Step 11: Use a laser coaxiality meter to re-measure the coaxiality of the drill rod (2-2) every 50 cm of drilling, and the deviation is ≤±0.5mm. If the sealing device (3-4) leaks, re-tighten the pressure plate (601) and increase the torque by 10%-15%; Step 12: When connecting the drill pipe (2-2), the interruption time is controlled within 3-5 minutes, the threaded casing (7-1) is connected at a jacking speed of 25 mm / min, and the hydrophilic nano-coating (2-4-1) on the inner wall of the high-pressure jet pipeline (2-4) is kept clean; Step 13: Retract the drill rod (2-2) at a speed of 30 mm / min. When the drill bit is retracted to the sealing device (3-4), close the ball valve (3-1) and the gate valve (3-2), and adjust the pressure fluctuation of the high-pressure pump (5-1) to within ±5% through the control center (5-3); Step 14: Use a special rod pulling tool to horizontally remove the drill rod (2-2), protect the sealing surface of the aramid packing (603) when removing the sealing device (3-4), and perform pre-maintenance on the sealing rubber gasket (604); Step 15: Rotate the blade disc (107) to the next cleaning point at 0.5-1 rpm, adjust the inclination angle of the support column (4-5) through the spherical rotary joint (4-17) of the power drive device (4), and repeat steps 1 to 14 to perform cyclic cleaning; Step 16: When removing the flushing device, record the wear status of the claw (401), the gear (402) and the transmission assembly (403), and replace the sealing rubber gasket (604); Step 17: Clean the site and check whether the thickness of the residual mud cake on the surface of the cutter disc (107) is less than 5 mm.

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