Intelligent rotary jet grouting drill bit

Abstract

The utility model discloses an intelligent rotary spraying drill bit which is composed of a rotary spraying body and a drilling drill bit detachably installed at the front end of the rotary spraying body and is provided with a controller. The rotary spraying body is of a circular drilling structure, the rear end of the rotary spraying body is in driving connection with the drill rod, the rotary spraying body is provided with a slurry conveying pipe, a water conveying pipe, a gas conveying pipe, a slurry storage cavity, a water storage cavity and a gas storage cavity which are communicated with one another, two groups of radial nozzles are formed in the peripheral wall of the rotary spraying body, and each group of nozzles comprises a slurry spraying opening, a water spraying opening and a gas spraying opening which are coaxially sleeved and independent; the drilling bit is provided with drilling teeth, and the axial end of the drilling bit is provided with a low-pressure slurry outlet and a parallel cooling water outlet. Through intelligent regulation and control, a multi-stage guniting structure and efficient heat dissipation design, the adaptability of the jet grouting drill bit to complex stratums is improved, and the technical problems that traditional equipment is low in efficiency, high in cost, unstable in pile forming quality and the like are solved.

Description

Technical Field

[0001] This utility model belongs to the field of building construction equipment design and structure, and particularly to the field of drilling construction equipment design and technology, specifically relating to an intelligent jet grouting drill bit for complex strata. Background Technology

[0002] In the fields of water conservancy and underground engineering technology, traditional jet grouting construction in complex strata faces numerous severe challenges. For example, in loose sand layers, the high porosity and unstable structure make conventional high-pressure grouting prone to grout loss, failing to effectively fill the pores, resulting in insufficient pile density and poor seepage prevention performance. In fractured rock strata, the grout spreads unevenly along the fractures due to the development of rock fissures, easily forming local weak areas, and high-pressure jetting can easily trigger secondary cracking of the rock mass. In clay strata, the drill bit easily adheres to the clay, leading to drill bit clogging, increased torque, and overheating, which accelerates wear. At the same time, high temperatures may change the physical properties of the soil, affecting the stability of the pile. In deep strata, the pressure of grout transport over long distances decreases significantly, the grout volume control accuracy is low, and problems such as grout interruption or grout accumulation are prone to occur. In multi-layered composite strata, different lithological strata alternate, and traditional equipment lacks dynamic adjustment capabilities, making it difficult to adapt to diverse working conditions. Summary of the Invention

[0003] This utility model discloses an intelligent rotary grouting drill bit to address the shortcomings of existing technologies. Through intelligent control, a multi-stage grouting structure, and efficient heat dissipation design, this rotary grouting drill bit improves its adaptability to complex geological formations and solves the technical problems of low efficiency, high cost, and unstable pile quality associated with traditional equipment.

[0004] This utility model is achieved through the following technical solution:

[0005] A smart rotary grouting drill bit, characterized in that: the rotary grouting drill bit consists of a rotary grouting body and a drilling bit that can be detachably installed at the front end of the rotary grouting body, and is equipped with a controller;

[0006] The jet nozzle is a circular drilling structure with its rear end connected to the drill rod drive. The jet nozzle is equipped with grout delivery pipes, water delivery pipes, and air delivery pipes that connect to the grout delivery equipment, water delivery equipment, and air delivery equipment, respectively. Inside the jet nozzle are grout storage chambers, water storage chambers, and air storage chambers that connect to the grout delivery pipes, water delivery pipes, and air delivery pipes, respectively. Two sets of radial nozzles are symmetrically arranged along the axial center of the jet nozzle's peripheral wall. Each set of nozzles includes a coaxially fitted independent grout nozzle, water nozzle, and air nozzle. The rear end of the grout nozzle is connected to the grout storage chamber via a pipe, the rear end of the water nozzle is connected to the water storage chamber via a pipe, and the rear end of the air nozzle is connected to the air storage chamber via a pipe. A resistive pressure sensor is installed at the outlet end of each grout nozzle, water nozzle, and air nozzle.

[0007] The drilling bit has drill teeth; the axial end of the drilling bit is provided with a low-pressure slurry outlet that is connected to the slurry storage chamber through a solenoid valve; the axial end of the drilling bit is also provided with a cooling water outlet that is connected to the water storage chamber through a solenoid valve.

[0008] The resistive pressure sensor, solenoid valve, and controller are connected for control.

[0009] Furthermore, a high-pressure nozzle is installed at the outlet of the pipeline connecting the water storage chamber and the spray nozzle. The high-pressure nozzle is connected to a plunger-type booster device integrated into the water storage chamber. The plunger-type booster device integrated inside the water storage chamber can increase the water pressure to the range of 15-30 MPa. The spray channel of the high-pressure nozzle adopts a tapered conical flow channel design, with the outlet diameter reduced by 60% compared to the inlet, achieving water flow acceleration through the Bernoulli effect. The opening and closing of the high-pressure nozzle is automatically switched by the intelligent control system according to the drilling stage: the auxiliary cutting mode is activated during drilling, and the self-cleaning mode is switched during grouting.

[0010] Furthermore, the low-pressure slurry outlet is linked to a solenoid valve. The solenoid valve is a proportional regulating type with a response time of ≤50ms. It monitors the pressure difference between the slurry storage chamber and the low-pressure slurry outlet in real time. When the pressure difference is >2MPa, it automatically increases the valve opening to maintain the low-pressure slurry outlet pressure stable at 0.5~1.5MPa, achieving low-pressure slurry outlet below the high-pressure slurry storage chamber, thus ensuring the uniformity and density of the seepage-proof wall.

[0011] Furthermore, the slurry storage chamber is a cylindrical double-layer shell structure, consisting of an outer pressure-bearing shell, an inner buffer cavity, and an annular pressure equalization groove. The volume of the slurry storage chamber is 1.5 to 2 times the volume of slurry injected from a single injection nozzle.

[0012] Furthermore, the slurry delivery pipe is a double-layered pipe structure consisting of an inner tungsten carbide alloy pipe and an outer glass fiber reinforced epoxy resin pipe.

[0013] The device of this utility model has the following advantages:

[0014] (1) A low-pressure cement slurry spraying structure is added. Through an independent low-pressure cement slurry channel, low-pressure cement slurry is sprayed out at the same time as high-pressure rotary spraying. The low-pressure cement slurry can effectively fill the gaps in the pile body, making the pile body more compact and stable, and greatly improving the seepage prevention effect. The low-pressure slurry outlet is linked with the solenoid valve to maintain the low-pressure slurry pressure.

[0015] (2) Built-in high-precision resistive pressure sensor accurately monitors the slurry pressure and provides real-time feedback on the equipment's operating status. Once the pressure fluctuates abnormally, it can provide timely warnings to ensure the stability and continuity of the construction process and guarantee the overall project progress and quality.

[0016] (3) By introducing solenoid valves, the opening and closing of the grouting nozzles can be precisely controlled. The grouting time period can be flexibly adjusted according to the construction process requirements, the grout distribution can be optimized, and the uniformity and integrity of the anti-seepage wall can be improved.

[0017] (4) Equipped with a grout storage chamber connected to the main cement grout delivery pipe, the grout storage chamber acts as a stable "grout supply buffer station" during the grouting process, balancing the grout pressure and maintaining a stable and continuous grouting state, thus avoiding pile quality problems caused by unstable grout supply. The grout storage chamber is a cylindrical double-layer shell structure, consisting of an outer pressure-bearing shell, an inner buffer chamber, and an annular pressure equalization groove. The outer pressure-bearing shell is made of high-strength stainless steel with a compressive strength ≥60MPa. The inner buffer chamber is molded from elastic polyurethane material, with a volume 1.5 to 2 times the grout volume of a single grouting operation. The inner wall of the chamber is uniformly coated with a nano-level hydrophobic coating to reduce grout adhesion residue. The annular pressure equalization groove is arranged at the bottom of the chamber, with radial guide holes inside to ensure uniform grout distribution along the circumference. During operation, the annular pressure equalization groove absorbs the instantaneous impact during high-pressure grouting, controlling the grout pressure fluctuation range within ±0.2MPa.

[0018] (5) The water outlet is cleverly designed on the drill bit. During construction, the water flows out from the water outlet, which can effectively remove the heat generated by the drill bit cutting the soil, prevent the drill bit from being damaged due to overheating, extend the service life of the drill bit, and at the same time avoid the adverse effects of high temperature on the properties of the surrounding soil.

[0019] (6) The grouting pipe adopts a main and auxiliary double-layer structure. The inner layer is a tungsten carbide alloy pipe (wear resistant) and the outer layer is a glass fiber reinforced epoxy resin pipe (pressure resistant and corrosion resistant). The double layers work together to improve the pipe's compressive strength (≥60MPa), and the pipe wall thickness is dynamically optimized according to the burial depth, taking into account both lightweight and durability.

[0020] (7) A high-pressure water jet cleaning nozzle is installed inside the nozzle. During construction breaks or after construction, the controller automatically activates the self-cleaning function to remove residual mud and soil particles inside the nozzle, preventing blockage, extending the nozzle's service life, and reducing maintenance workload. The high-pressure nozzle adopts a tapered converging flow channel, which is pressurized by a plunger pump in the water storage tank to form a high-speed jet. During drilling, the swirling flow assists cutting, and after spraying, it performs pulse self-cleaning. The water storage tank is made of high-pressure resistant composite material and has a built-in flow regulating valve and spiral guide structure. During drilling, part of the water is transported through the water spray pipe to the spiral guide groove of the drill bit to form turbulence covering the cutting surface, achieving efficient heat dissipation; the other part of the water is used to assist spraying and clean the pipeline.

[0021] (8) The controller can dynamically switch between high and low pressure grouting modes through the built-in formation adaptive algorithm of the intelligent control system: low pressure filling is given priority in loose formations, and high pressure reinforcement is used; the proportion of gas injection is increased in fractured rock formations to expand the penetration range by using gas-liquid coupling; and the cooling water flow rate is increased in clay formations to avoid drill bit jamming.

[0022] This novel intelligent rotary grouting drill bit employs a pre-drilling, post-grouting approach. During grouting, the grout first enters the storage chamber, then passes through a resistive pressure sensor and is ejected from the nozzle. A second portion of the grout is controlled by a solenoid valve and ejected from a low-pressure outlet. This facilitates filling gaps in the pile body, enhances pile density, and significantly improves seepage prevention efficiency. The drill bit also features a cooling water outlet. During construction, the water flow carries away the cutting heat of the drill bit, preventing overheating damage, extending its lifespan, and mitigating the adverse effects of high temperatures on the surrounding soil. This intelligent rotary grouting drill bit effectively overcomes the challenges of deep, high-depth seepage prevention construction in complex strata, ensuring the formation of a high-strength, highly sealed rotary grouting seepage prevention structure, providing a solid foundation for various water conservancy and underground engineering projects. Attached Figure Description

[0023] Figure 1 This is a perspective view of the rotary jet drill bit of this utility model;

[0024] Figure 2 This is a planar perspective view of the rotary jet drill bit of this utility model;

[0025] Figure 3 This is a side view of the rotary jet drill bit of this utility model;

[0026] Figure 4 This is a schematic diagram of the nozzle assembly of the rotary jet drill bit of this utility model.

[0027] The attached diagram is labeled as follows: 1 is the slurry delivery pipe, 2 is the water delivery pipe, 3 is the air delivery pipe, 4 is the resistive pressure sensor, 5 is the solenoid valve, 6 is the slurry storage chamber, 7 is the water storage chamber, 8 is the air storage chamber, 9 is the nozzle, 9a is the slurry nozzle, 9b is the water nozzle, 9c is the air nozzle, 10 is the high-pressure nozzle, 11 is the low-pressure slurry outlet, 12 is the cooling water outlet, 13 is the drill bit, and 14 is the controller. Detailed Implementation

[0028] The present invention will be further described below with reference to specific embodiments. These specific embodiments are further explanations of the principle of the present invention and are not intended to limit the present invention in any way. Any technology that is the same as or similar to the present invention does not exceed the protection scope of the present invention.

[0029] Refer to the attached diagram.

[0030] As shown in the figure, the intelligent rotary jet drill bit of this utility model consists of a rotary jet body and a drilling bit that can be detachably installed at the front end of the rotary jet body, and is equipped with a controller 14.

[0031] The jet nozzle is a circular drilling structure with its rear end connected to the drill rod drive. The jet nozzle is equipped with a slurry delivery pipe 1, a water delivery pipe 2, and an air delivery pipe 3, which are respectively connected to the slurry delivery equipment, water delivery equipment, and air delivery equipment. The jet nozzle body is also equipped with a slurry storage chamber 6, a water storage chamber 7, and an air storage chamber 8, which are respectively connected to the slurry delivery pipe 1, water delivery pipe 2, and air delivery pipe 3. Two sets of radial nozzles 9 are symmetrically arranged along the axial center of the jet nozzle's peripheral wall. Each set of nozzles 9 includes a coaxially mounted independent slurry nozzle 9a, a water nozzle 9b, and an air nozzle 9c. The rear end of the slurry nozzle 9a is connected to the slurry storage chamber 6 via a pipe; the rear end of the water nozzle 9b is connected to the water storage chamber 7 via a pipe; and the rear end of the air nozzle 9c is connected to the air storage chamber 8 via a pipe. Each outlet end of the slurry nozzle 9a, water nozzle 9b, and air nozzle 9c is equipped with a resistive pressure sensor 4 and a solenoid valve 5.

[0032] The drilling bit has drill teeth 13; the axial end of the drilling bit is provided with a low-pressure slurry outlet 11 that is connected to the slurry storage chamber 6 through a solenoid valve 5; the axial end of the drilling bit is also provided with a cooling water outlet 12 that is connected to the water storage chamber 7 through a solenoid valve 5.

[0033] The resistive pressure sensor 4, the solenoid valve 5, and the controller 14 are connected for control.

[0034] As shown in the figure, nozzle 9 consists of a slurry nozzle 9a, an air jet nozzle 9c, and a water jet nozzle 9b. The slurry nozzle 9a is fitted inside the water jet nozzle 9b, and the air jet nozzle 9c is fitted outside the water jet nozzle 9b. The inner ends of the slurry nozzle 9a, air jet nozzle 9c, and water jet nozzle 9b are connected to the slurry storage chamber 6, the air storage chamber 8, and the water storage chamber 7 respectively through pipes.

[0035] The grout storage chamber 6 is connected to the grout delivery pipe 1, the nozzle 9, and the low-pressure grout outlet 11. During the grouting process, the grout storage chamber 6 acts as a "grout supply buffer station," which can balance the grout outlet pressure, maintain a stable and continuous grout outlet state, and avoid pile quality problems caused by unstable grout supply.

[0036] The high-pressure nozzle 10 is connected to the water storage chamber 7 of the equipment. Through the pre-set pipes and nozzles inside the nozzle 9, it sprays high-pressure water into the nozzle 9 and nozzles at specific times to remove residual mud and soil particles. The high-pressure nozzle 10 is connected to the water storage chamber 7 via a high-pressure water pump, and the water storage shell has a built-in plunger pressurization mechanism. The high-pressure nozzle 10 is designed as a tapered conical flow channel with a diameter reduced by 60% from the inlet to the outlet. Its working mode is automatically adjusted by the intelligent system according to the construction stage. The auxiliary cutting function is activated during the drilling stage, and the self-cleaning state is switched during the grouting stage.

[0037] The low-pressure grout outlet 11 is connected to the drilling bit through an independent low-pressure cement grout channel. Low-pressure cement grout is sprayed out at the same time as high-pressure jet grouting. The low-pressure cement grout can effectively fill the gaps in the pile body, enhance the density of the pile body, and improve the seepage prevention effect.

[0038] A resistive pressure sensor 4 is installed in the pipe at the front end of the nozzle 9. Its function is to monitor the discharge pressure inside the equipment in real time and feed the signal back to the control system. Once abnormal pressure fluctuations occur, the control system will issue an early warning.

[0039] Solenoid valve 5 is installed in the low-pressure grout outlet 11 and the cooling water outlet 12. Its function is to precisely control the opening and closing of the low-pressure grout outlet and the cooling water outlet. It allows for flexible adjustment of the grouting time according to construction needs, optimizing grout distribution and improving the uniformity and integrity of the anti-seepage wall. Simultaneously, it controls the spraying of cooling water for heat dissipation.

[0040] Cooling water outlet 12 is located at the end of the drill bit. Its function is to effectively remove the heat generated by the drill bit cutting the soil during equipment construction, prevent the drill bit from being damaged due to overheating, extend the service life of the drill bit, and at the same time avoid the adverse effects of high temperature on the properties of the surrounding soil.

[0041] The following details the construction and application methods of this utility model's intelligent rotary jet grouting drill bit.

[0042] Pre-construction preparation: The construction site must be cleared and leveled in advance, removing all obstacles to ensure smooth equipment entry and operation. Accurately measure and lay out the lines according to the engineering design requirements to determine the pile positions, with pile position deviations strictly controlled within the allowable range. Conduct a comprehensive and meticulous inspection of all components of the equipment, ensuring that the grout delivery pipe 1, water delivery pipe 2, and air delivery pipe 3 are undamaged and unblocked, and that connections are secure and tight; check the performance of electrical components such as the resistive pressure sensor 4 and solenoid valve 5 to ensure their sensitivity and reliability; confirm that the grout storage chamber 6, water storage chamber 7, and air storage chamber 8 are leak-free and that the storage capacity meets construction requirements. Simultaneously, debug the intelligent control system, inputting data such as geological parameters and construction process requirements to complete equipment calibration and initialization, enabling it to operate accurately according to the preset program.

[0043] Drilling Operation: After the equipment is in place, its verticality is precisely adjusted to ensure that the verticality deviation of the drill rod does not exceed the specified value, preventing borehole tilting from affecting the pile quality. The equipment is started, and the drill bit rotates under the drive of the motor to drill into the soil. During drilling, the water supply pipe 2 continuously sprays cooling water around the drill bit through the water storage chamber 7 and cooling water outlet 12. The water flow forms turbulence through the annular guide vane groove on the outside of the drill bit, efficiently carrying away cutting heat and ensuring that the drill bit's operating temperature is below 80℃. This avoids overheating that could lead to accelerated wear or damage to the drill bit, extending its service life and preventing adverse effects of high temperatures on the surrounding soil properties. For rock formations with a hardness ≤8, the PDC cutter head at the drill bit's tip provides powerful cutting capabilities.

[0044] Shotcreting Operation: After the drill bit reaches the designed depth, shotcreting begins. Slurry enters from the slurry delivery pipe 1 through the slurry storage chamber 6. The volume of the storage chamber 6 is 1.5 to 2 times the volume of slurry injected in a single pass through the slurry delivery pipe 1. An elastic diaphragm is flexibly connected to the main slurry pipe to absorb pressure fluctuations, stabilizing the slurry pressure and balancing the slurry flow rate. A resistive pressure sensor 4 monitors the slurry pressure in real time and feeds the data back to the intelligent control system. When abnormal pressure fluctuations occur, the system issues a timely warning, allowing operators to adjust equipment parameters accordingly to ensure stable construction. The slurry is ejected from the nozzle 9a, forming a high-pressure swirling jet that cuts and mixes the soil. Simultaneously, the solenoid valve 5 dynamically adjusts the opening of the low-pressure outlet 11 and the shotcreting duration based on a preset program or real-time geological parameters using a PID algorithm. Low-pressure cement slurry is ejected from the low-pressure outlet, filling the gaps in the pile body and enhancing its density and impermeability.

[0045] Auxiliary jetting operation: Water supply pipe 2 and air supply pipe 3 work together according to construction needs. In loose sand layers, the jetting ratio of jet nozzle 9c is increased to assist the grout in filling pores using pneumatic impact; in fractured rock layers, gas jetting expands the grout penetration range; in clay layers, the water jetting volume of water nozzle 9b is appropriately increased to coordinate with the cooling water outlet 12, reducing drill bit temperature and preventing drill bit jamming. The special layout of nozzles 9, with grout nozzle 9a located in the center, symmetrical water nozzles 9b on both sides, and an outermost annular jet nozzle 9c, ensures uniform and efficient coordination of the jetting of various media.

[0046] Construction process monitoring and adjustment: Throughout the construction process, a 4C resistive pressure sensor monitors the grout pressure in real time. The intelligent control system, based on sensor data and a formation adaptive algorithm, automatically matches the grouting pressure, flow rate, and drilling speed. Operators can view equipment operating parameters, grout diffusion simulation diagrams, temperature distribution, and drill bit wear warnings in real time using the equipment display screen or a remote monitoring terminal, allowing for timely intervention and adjustments. If abnormal pressure, flow fluctuations, or other malfunctions are detected, construction is immediately suspended, and operations resume after investigation and repair, ensuring construction quality and safety.

[0047] Post-construction processing: After construction, the equipment automatically activates its self-cleaning function. High-pressure nozzles 10 spray high-pressure water (≥15MPa) into the pipes and nozzles for 3-5 seconds to remove residual mud and soil particles. After cleaning, pressure sensors verify nozzle patency; if the blockage rate is >5%, a secondary cleaning is triggered to ensure proper operation for the next use. A comprehensive cleaning and maintenance of the equipment is performed, checking for wear on all components and replacing damaged parts promptly to prepare for the next construction phase.

Claims

1. An intelligent jetting bit, comprising: The rotary grouting drill bit consists of a rotary grouting body and a drilling bit that can be detachably installed at the front end of the rotary grouting body, and is equipped with a controller; The jet nozzle is a circular drilling structure with its rear end connected to the drill rod drive. The jet nozzle is equipped with grout delivery pipes, water delivery pipes, and air delivery pipes that connect to the grout delivery equipment, water delivery equipment, and air delivery equipment, respectively. Inside the jet nozzle are grout storage chambers, water storage chambers, and air storage chambers that connect to the grout delivery pipes, water delivery pipes, and air delivery pipes, respectively. Two sets of radial nozzles are symmetrically arranged along the axial center of the jet nozzle's peripheral wall. Each set of nozzles includes a coaxially fitted independent grout nozzle, water nozzle, and air nozzle. The rear end of the grout nozzle is connected to the grout storage chamber via a pipe, the rear end of the water nozzle is connected to the water storage chamber via a pipe, and the rear end of the air nozzle is connected to the air storage chamber via a pipe. A resistive pressure sensor is installed at the outlet end of each grout nozzle, water nozzle, and air nozzle. The drilling bit has drill teeth; the axial end of the drilling bit is provided with a low-pressure slurry outlet that is connected to the slurry storage chamber through a solenoid valve; the axial end of the drilling bit is also provided with a cooling water outlet that is connected to the water storage chamber through a solenoid valve. The resistive pressure sensor, solenoid valve, and controller are connected for control.

2. The intelligent jetting bit of claim 1, wherein: The outlet of the pipeline connecting the water storage chamber and the spray nozzle is equipped with a high-pressure nozzle, which is connected to a plunger-type pressurization device integrated in the water storage chamber.

3. The intelligent jetting bit of claim 2, wherein: The high-pressure nozzle adopts a tapered converging flow channel structure, with the outlet diameter reduced by 60% compared to the inlet diameter.

4. The intelligent jetting bit of claim 1, wherein: The slurry storage chamber is a cylindrical double-layer shell structure, consisting of an outer pressure-bearing shell, an inner buffer cavity, and an annular pressure equalization groove.

5. The intelligent jetting bit of claim 4, wherein: The volume of the slurry storage chamber is 1.5 to 2 times the volume of slurry injected from a single slurry nozzle.

6. The intelligent jetting bit of claim 1, wherein: The grout delivery pipe is a double-layered pipe structure consisting of an inner tungsten carbide alloy pipe and an outer glass fiber reinforced epoxy resin pipe.

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