A high-efficiency rotary dredging device for a deepwater well

Abstract

The present application belongs to the technical field of deep water well dredging equipment, and particularly relates to a high-efficiency rotary cutting dredging device for deep water well, comprising a connecting section, a shunt pipe, an inner rotating pipe, an outer rotating pipe, a first rotary cutter, a second rotary cutter and a shearing cutter. The shunt pipe is fixed below the connecting section, the inner rotating pipe is rotationally arranged inside the shunt pipe, and the inner wall of the inner rotating pipe is provided with first turbine blades; the outer rotating pipe is rotationally arranged outside the shunt pipe, and the inner wall of the outer rotating pipe is provided with second turbine blades. High-pressure water is divided into two paths through the shunt pipe, and the inner rotating pipe drives the first rotary cutter to rotate in a first direction, and the outer rotating pipe drives the second rotary cutter and the shearing cutter to rotate in a second direction in the opposite direction. The outer wall of the outer rotating pipe is hingedly connected with the second rotary cutter, and can be self-adaptively expanded to fit different well diameters according to the centrifugal force. The bottom end of the outer rotating pipe is provided with the shearing cutter, and the shearing cutter forms staggered shearing cooperation with the first blade to cut off the winding object. The present application is driven by pure water power, and does not need underground electrical elements, and has the characteristics of anti-winding, self-adaptive well diameter and high deslagging efficiency.

Description

Technical Field

[0001] This invention belongs to the technical field of deep water well dredging equipment, and particularly relates to a high-efficiency rotary cutting dredging device for deep water wells. Background Technology

[0002] During long-term use, deep wells accumulate deposits of hardened silt, solidified fine sand, rust, and other debris at the bottom, and scale builds up on the well walls, severely impacting water output and quality. Currently, deep well dredging operations primarily employ high-pressure water jet cleaning, mechanical rotary cutting, and negative pressure suction. High-pressure water jet cleaning relies on hydraulic scouring, but its ability to break up hardened silt layers is limited, making it difficult to effectively remove dense sediments. While mechanical rotary cutting has a breaking function, it generally relies on hydraulic motors or electric motors as the downhole power source, requiring underground cable installation, resulting in high system complexity. Furthermore, in the high-pressure environment of deep water, seals are prone to failure and insulation damage, making equipment reliability difficult to guarantee. Negative pressure suction is mainly suitable for loose gravel layers and has poor adaptability to hardened silt.

[0003] Existing mechanical rotary cutting dredging methods still have the following problems: the rotary cutting head mostly rotates in one direction, which can easily cause entanglement and jamming when encountering fibrous debris such as tree roots, ropes, and plastic bags, leading to a sudden increase in torque or even overload and damage to the drive device, seriously affecting the continuity of operation; the scraping or rotary cutting structure is mostly of fixed size and cannot adapt to well walls of different diameters. When the well diameter changes, the scraping arm is difficult to fit tightly, resulting in poor dredging effect. Summary of the Invention

[0004] The purpose of this invention is to provide a high-efficiency rotary cutting dredging device for deep water wells, so as to solve the technical problems of existing deep water well dredging devices that rely on downhole electrical power sources, resulting in poor reliability, easy entanglement and jamming due to a single rotation direction, and fixed-size scraping structure that cannot adapt to different well diameters.

[0005] To achieve the above objectives, the specific technical solution of the high-efficiency rotary cutting dredging device for deep water wells according to the present invention is as follows: A high-efficiency rotary cutting and dredging device for deep wells includes a connecting section, the inner wall of which is provided with a threaded connection structure for connecting the drill rod, and a high-pressure water flow channel is formed inside the connecting section; A diversion pipe is fixedly installed below the connecting section, with the top end of the diversion pipe extending into the interior of the connecting section, and an annular diversion gap formed between the outer wall of the diversion pipe and the inner wall of the connecting section. An inner rotating tube is rotatably disposed inside the splitter tube. The upper and lower ends of the inner rotating tube are rotatably engaged with the splitter tube through a first bearing. Multiple first turbine blades are arranged circumferentially on the inner wall of the inner rotating tube. An outer rotating tube is rotatably disposed outside the splitter tube. The upper end of the outer rotating tube is rotatably connected to the lower end of the connecting section through a second bearing, and the lower end of the outer rotating tube is rotatably connected to the lower end of the splitter tube through a third bearing. Multiple second turbine blades are circumferentially arranged on the inner wall of the outer rotating tube, and the rotation direction of the second turbine blades is opposite to that of the first turbine blades. The first rotary cutter is fixedly connected to the bottom end of the inner rotating tube, and the first rotary cutter includes a plurality of first blades evenly distributed in the circumferential direction; Multiple second rotary cutting blades are equidistantly hinged to the outer wall of the outer rotating tube. Each second rotary cutting blade includes a second blade, and an elastic reset member is connected between the upper end of the second blade and the outer wall of the outer rotating tube. A shearing blade is fixedly installed at the bottom end of the outer rotating tube. The shearing blade is located above the rotation trajectory of the first blade and forms a shearing engagement with the upper side edge of the first blade. After the high-pressure water flows into the connecting section, it is divided by the diversion pipe into a first flow channel that flows through the inner rotating pipe and a second flow channel that flows through the annular diversion gap between the diversion pipe and the outer rotating pipe. The first flow channel impacts the first turbine blade, driving the inner rotating pipe to rotate the first rotary cutter along the first direction. The second flow channel impacts the second turbine blade, driving the outer rotating pipe to rotate multiple second rotary cutters and shearing blades along the second direction. The first direction is opposite to the second direction.

[0006] Furthermore, the outer wall of the diversion pipe and the inner wall of the connecting section are fixedly connected by multiple support columns.

[0007] Furthermore, the bottom end of the outer rotating pipe is an arc-shaped closed structure, and multiple water outlets are circumferentially equidistantly opened on the side wall near the bottom end of the outer rotating pipe. The opening direction of the water outlets is inclined upward. The high-pressure water flowing through the second flow channel is turned by the arc-shaped surface at the bottom end of the outer rotating pipe and discharged obliquely upward from the water outlet to the space between the outer rotating pipe and the well wall.

[0008] Furthermore, the top end of the diverter is a tapered flow guide structure.

[0009] Furthermore, both the upper and lower edges of the first blade are sharpened; multiple shearing blades are arranged circumferentially along the bottom end of the outer rotating tube, and there is an interlaced shearing gap between the cutting edge of the shearing blade and the upper cutting edge of the first blade.

[0010] Furthermore, the first rotary cutter is connected to the bottom end of the inner rotating tube through a connection port in the middle, and the connection port and the inner rotating tube are fixed by a threaded connection or a snap-fit ​​method; the bottom end of the inner rotating tube and the connection port are fixedly connected by multiple connecting posts.

[0011] Furthermore, the hinge point of the second rotary cutter is located at the lower end of the outer wall of the outer rotating tube, and the second blade extends outward at an angle from the hinge point; the elastic reset member is a tension spring, one end of which is connected to the second blade and the other end is connected to the outer wall of the outer rotating tube.

[0012] Furthermore, a protective wheel is rotatably provided at the end of the second blade. The protective wheel is used to reduce frictional resistance when the second blade is in contact with the well wall, and at the same time prevent the second blade from being damaged due to direct contact with the hard well wall.

[0013] The operation method of the high-efficiency rotary cutting dredging device for deep water wells includes the following steps: S1: Fix the connecting section to the drill pipe and lower the device to the bottom silt layer of the deep water well; S2: High-pressure water is introduced into the connecting section through the drill rod. After the high-pressure water is smoothly diverted by the conical guide structure at the top of the diversion pipe, it enters the first flow channel inside the inner rotating pipe and the second flow channel between the outer wall of the diversion pipe and the inner wall of the outer rotating pipe, driving the inner rotating pipe and the outer rotating pipe to rotate in opposite directions. S3: The first rotary cutter, driven by the inner rotating tube, cuts and breaks up the sludge deposits at the bottom of the well. At the same time, the centrifugal force generated by the rotation of the outer rotating tube causes the second rotary cutter, which is hinged on the outer wall of the outer rotating tube, to open outward against the tension of the elastic reset member, so that the second blade fits tightly against the well wall of different diameters and performs adaptive scraping and cleaning of the deposits on the well wall. S4: The protective wheel at the end of the second blade rolls against the well wall during the scraping process, converting sliding friction into rolling friction to reduce rotational resistance. At the same time, the protective wheel forms a physical isolation layer between the second blade and the hard well wall to prevent the second blade from chipping or breaking due to direct contact with hard rock layers or well wall protrusions. S5: During the rotary cutting process, the shearing blade and the rotating first blade form an alternating shearing action to cut one or more of the fibrous debris such as tree roots, ropes, and plastic bags wrapped around the first blade. S6: The high-pressure water flowing through the second flow channel continues to flow downward after impacting the second turbine blades and doing work. After turning at the arc-shaped surface at the bottom of the outer rotating pipe, it is sprayed obliquely upward from the water outlet on the side wall of the outer rotating pipe to the space between the outer rotating pipe and the well wall, carrying the broken sludge upward. S7: Start the ground negative pressure suction equipment to form a negative pressure at the top of the annulus between the outer rotating pipe and the well wall, and force the sludge-water mixture in the annulus to be sucked out. Together with the high-pressure water carrying effect, the sludge at the bottom of the well is continuously discharged from the wellhead to complete the dredging operation.

[0014] The high-efficiency rotary cutting dredging device for deep water wells of the present invention has the following advantages: The high-pressure water flow is divided into two paths by a diversion pipe, which drive the first turbine blade on the inner rotating pipe and the second turbine blade on the outer rotating pipe to rotate in opposite directions, thereby driving the bottom rotary cutting head and the well wall scraping arm to work together. The entire device does not require the installation of motors, hydraulic motors or cables downhole. It can achieve all power output by simply delivering high-pressure water through conventional drill pipes on the surface, avoiding safety hazards such as electrical insulation damage and hydraulic seal failure in deep water and high pressure environments.

[0015] This device splits the high-pressure water flow into two through a diversion pipe, driving the inner and outer rotating pipes to rotate in opposite directions. This allows the first rotary cutter at the bottom and the second rotary cutter on the well wall to operate simultaneously in opposite directions. The inner rotating pipe drives the first cutter to rotate clockwise, actively cutting and breaking up the deposits on the bottom of the well; the outer rotating pipe drives the second rotary cutter to rotate counterclockwise, scraping and cleaning the deposits on the well wall. Working together, both the bottom and the well wall can be cleaned in a single run. Simultaneously, the opposing counter-torques generated by the inner and outer rotors cancel each other out within the device through the stationary diversion pipe, resulting in a lower net torque transmitted to the top drill pipe. Therefore, the surface drill pipe does not require an anti-torque device and is only used as a water supply channel and load-bearing lifting component, reducing the configuration requirements of the surface equipment.

[0016] A shearing blade is fixedly installed at the bottom of the outer rotating tube. The shearing blade is located above the rotation trajectory of the first blade, and there is an alternating shearing gap between it and the upper cutting edge of the first blade. When the inner rotating tube drives the first blade to rotate clockwise, the upper cutting edge of the first blade and the cutting edge of the shearing blade, which rotates counterclockwise with the outer rotating tube, form relative motion. When fibrous debris such as tree roots, ropes, and plastic bags from the bottom of the deep well become entangled at the root of the first blade, they will be drawn into the shearing gap during rotation and cut off by the alternating shearing action of the two cutting edges. This structural design solves the problem of easy entanglement and jamming in traditional single-rotational-direction rotary cutting devices from a physical perspective. It eliminates the need for additional cutting devices, and is compact and reliable in function.

[0017] The second rotary cutter is hinged at the lower end of the outer wall of the outer rotating pipe. The second blade extends outward at an angle from the hinge point, and a tension spring connects the second blade to the outer wall of the outer rotating pipe. During the device's lowering into the well, the outer rotating pipe does not rotate or rotates at a low speed. The tension spring retracts the second blade to adhere to the outer wall of the outer rotating pipe, minimizing the overall outer diameter of the device and facilitating smooth lowering in narrow wellbore. When the device reaches the working position and the outer rotating pipe rotates at high speed, centrifugal force overcomes the tension spring, causing the second blade to open outward. The opening amplitude is positively correlated with the rotation speed, automatically adapting to well walls of different diameters and maintaining a certain wall-adhering pressure. Compared to existing fixed-size scraping structures, the adaptive expansion design of the second rotary cutter improves adaptability to different well diameter conditions.

[0018] A protective wheel is rotatably installed at the end of the second blade. When the second blade rotates and scrapes against the well wall under the action of centrifugal force, the protective wheel and the well wall experience rolling friction, which reduces the frictional resistance between the second blade and the well wall and reduces the rotational energy consumption of the outer rotating pipe. At the same time, the protective wheel forms a physical isolation layer between the second blade and the hard well wall. When there are hard rock layers or protrusions on the well wall, the protective wheel will first contact and roll over the obstacle, effectively preventing the cutting edge of the second blade from directly hitting the hard object and causing chipping and damage, thus extending the service life of the second rotary cutter.

[0019] An arc-shaped closed structure is adopted at the bottom of the outer rotating pipe, and multiple upward-sloping water outlets are circumferentially and evenly spaced on the side wall near the bottom. High-pressure water flowing through the second flow channel, after impacting the second turbine blades and performing work, continues to flow downwards to the bottom of the outer rotating pipe. After a smooth turn on the arc-shaped surface, it is ejected from the upward-sloping water outlets, forming an upward-sloping jet. This jet acts directly on the bottom of the annular gap between the outer rotating pipe and the well wall, causing the sludge produced by the rotary shearing and crushing to surge upwards and suspend, effectively preventing the heavier gravel from re-settling at the bottom of the well, thus creating favorable conditions for subsequent slag removal. Attached Figure Description

[0020] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a cross-sectional structural diagram of the present invention; Figure 3 For the present invention Figure 2 Enlarged view of region A in the middle; Figure 4 For the present invention Figure 2 Enlarged view of region B in the middle; The markings in the diagram are as follows: 1. Connecting section; 2. Diverter pipe; 3. Inner rotating pipe; 4. First bearing; 5. First turbine blade; 6. Outer rotating pipe; 7. Second bearing; 8. Third bearing; 9. Second turbine blade; 10. First rotary cutter; 11. First blade; 12. Second rotary cutter; 13. Second blade; 14. Elastic reset element; 15. Shearing blade; 16. Water outlet; 17. Protective wheel. Detailed Implementation

[0021] To better understand the purpose, structure, and function of this invention, the following detailed description of a high-efficiency rotary cutting and dredging device for deep wells, in conjunction with the accompanying drawings, is provided.

[0022] like Figure 1-4 As shown, the present invention provides a high-efficiency rotary cutting and dredging device for deep wells. The connecting section 1 has a threaded connection structure on its top inner wall for connecting the drill rod, and a high-pressure water flow channel is formed inside the connecting section 1. Diverter pipe 2 is fixedly installed below the connecting section 1. The top end of the diverter pipe 2 extends into the interior of the connecting section 1, and an annular diverter gap is formed between the outer wall of the diverter pipe 2 and the inner wall of the connecting section 1. The inner rotating tube 3 is rotatably disposed inside the split tube 2. The upper and lower ends of the inner rotating tube 3 are rotatably engaged with the split tube 2 through the first bearing 4. The inner wall of the inner rotating tube 3 is circumferentially provided with a plurality of first turbine blades 5. The outer rotating pipe 6 is rotatably disposed outside the diverter pipe 2. The upper end of the outer rotating pipe 6 is rotatably connected to the lower end of the connecting section 1 through the second bearing 7, and the lower end of the outer rotating pipe 6 is rotatably connected to the lower end of the diverter pipe 2 through the third bearing 8. The inner wall of the outer rotating pipe 6 is circumferentially provided with a plurality of second turbine blades 9, and the rotation direction of the second turbine blades 9 is opposite to that of the first turbine blades 5. The first rotary cutter 10 is fixedly connected to the bottom end of the inner rotating tube 3. The first rotary cutter 10 includes a plurality of first blades 11 evenly distributed in the circumferential direction. Multiple second rotary cutting blades 12 are equidistantly hinged on the outer wall of the outer rotating tube 6. Each second rotary cutting blade 12 includes a second blade 13, and an elastic reset member 14 is connected between the upper end of the second blade 13 and the outer wall of the outer rotating tube 6. The shearing blade 15 is fixedly disposed at the bottom end of the outer rotating tube 6. The shearing blade 15 is located on the upper side of the rotation trajectory of the first blade 11 and forms a shearing engagement with the upper side edge of the first blade 11. After the high-pressure water flows into the connecting section 1, it is divided by the diversion pipe 2 into a first flow channel that flows through the inner rotating pipe 3 and a second flow channel that flows through the annular diversion gap between the diversion pipe 2 and the outer rotating pipe 6. The first flow channel impacts the first turbine blade 5, which drives the inner rotating pipe 3 to rotate the first rotary cutter 10 in a first direction. The second flow channel impacts the second turbine blade 9, which drives the outer rotating pipe 6 to rotate multiple second rotary cutters 12 and shearing blades 15 in a second direction. The first direction is opposite to the second direction.

[0023] Combination Figure 1-4 As shown, a high-efficiency rotary cutting dredging device for deep water wells has a coaxial rotating structure. From top to bottom, it is divided into four functional sections: a top connecting and diverting section, a middle turbine drive section, a lower scraping arm section, and a lower cutting section. The entire device is connected to the drill pipe via the top connecting section 1. The drill pipe is hoisted and lowered into the deep water well. High-pressure water is transported to the device through the drill pipe's inner cavity, and after being diverted by the diverting pipe 2, it drives the inner rotating pipe 3 and the outer rotating pipe 6 to rotate in opposite directions, thereby driving the first rotary cutter 10 and the second rotary cutter 12 to perform dredging operations on the well bottom and well wall.

[0024] like Figure 2As shown, connecting section 1 is a tubular structure with a threaded connection structure on its top inner wall for connecting the drill pipe, adapting to the standard drill pipe of a conventional water well drilling rig. The interior of connecting section 1 is hollow, forming a high-pressure water flow channel through which the high-pressure water inside the drill pipe enters the device. The outer wall of connecting section 1 can be machined into a uniform diameter cylindrical surface or a multi-stepped shape as needed, to adapt to wellhead sealing devices of different diameters.

[0025] The diverter pipe 2 is fixedly installed below the connecting section 1, with its top end extending into the interior of the connecting section 1. An annular diverter gap is formed between the outer wall of the diverter pipe 2 and the inner wall of the connecting section 1. To achieve a fixed connection between the diverter pipe 2 and the connecting section 1, the outer wall of the diverter pipe 2 and the inner wall of the connecting section 1 are fixedly connected by multiple support columns. The support columns are evenly distributed circumferentially, and the gaps between adjacent support columns form the flow channel of the annular diverter gap, ensuring sufficient flow area while guaranteeing connection strength.

[0026] The top of the diversion pipe 2 is designed with a conical guide structure, meaning the top of the diversion pipe 2 has a tapered transition section that is smaller at the top and larger at the bottom. After the high-pressure water flows down from above the connecting section 1, the conical guide structure smoothly divides the water. Part of the water enters the interior of the diversion pipe 2, while the other part flows downward along the annular diversion gap between the outer wall of the diversion pipe 2 and the inner wall of the connecting section 1. The conical guide structure effectively avoids eddy current losses and pressure losses caused by right-angle turns, thus improving the efficiency of hydraulic energy utilization.

[0027] The lower end of the diverter pipe 2 extends to the lower end of the outer rotating pipe 6, and its lowest end is rotatably connected to the lower end of the outer rotating pipe 6 through the third bearing 8. A through hole is provided at the center of the bottom end of the diverter pipe 2 for the inner rotating pipe 3 to pass through, and the through hole is sealed to the outer wall of the inner rotating pipe 3.

[0028] The central turbine drive section includes an inner rotating pipe 3, a first bearing 4, a first turbine blade 5, an outer rotating pipe 6, a second bearing 7, a third bearing 8, and a second turbine blade 9. The inner rotating pipe 3 is a hollow tubular structure, rotatably mounted inside the diversion pipe 2. A through-hole water hole is located at the center of the inner rotating pipe 3, forming the main body of the first flow channel, used to deliver high-pressure water to the bottom first rotary cutter 10. The upper and lower ends of the inner rotating pipe 3 are rotatably engaged with the diversion pipe 2 via the first bearing 4, achieving axial load bearing.

[0029] Multiple first turbine blades 5 are arranged circumferentially on the inner wall of the inner rotating pipe 3. The first turbine blades 5 are evenly distributed along the inner wall of the inner rotating pipe 3. When high-pressure water flows from top to bottom through the interior of the inner rotating pipe 3, the water flow impacts the first turbine blades 5, driving the inner rotating pipe 3 to rotate within the diversion pipe 2.

[0030] The outer rotating pipe 6 is a cylindrical structure and is rotatably mounted outside the diverter pipe 2. The outer rotating pipe 6 is sleeved on the outside of the diverter pipe 2, forming an annular diverter gap between the two. The upper end of the outer rotating pipe 6 is rotatably connected to the lower end of the connecting section 1 through the second bearing 7, and the lower end of the outer rotating pipe 6 is rotatably connected to the lower end of the diverter pipe 2 through the third bearing 8, so as to achieve axial bearing. Multiple second turbine blades 9 are circumferentially arranged on the inner wall of the outer rotating pipe 6, evenly distributed along the inner wall of the outer rotating pipe 6, with the inclination direction opposite to that of the first turbine blades 5. When high-pressure water flows from top to bottom through the annular diverter gap between the outer wall of the diverter pipe 2 and the inner wall of the outer rotating pipe 6, the water flow impacts the second turbine blades 9, driving the outer rotating pipe 6 to rotate in the opposite direction to the inner rotating pipe 3.

[0031] Combination Figure 1-4 As shown, the lower-middle scraping arm section is located on the outer wall of the middle section of the outer rotating tube 6, including multiple second rotary cutting blades 12 and elastic reset members 14. The second rotary cutting blades 12 are equidistantly hinged on the outer wall of the outer rotating tube 6, and the hinge point of the second rotary cutting blade 12 is located at the lower end of the outer wall of the outer rotating tube 6, that is, the lower end of the second rotary cutting blade 12 is connected to the lower end of the mounting groove through a hinge pin. The second rotary cutting blade 12 includes a second blade 13, which extends outward from the hinge point. A protective wheel 17 is rotatably mounted on the end of the second blade 13 (i.e., the upper free end), and is mounted on the wheel axle at the end of the second blade 13 through a rolling bearing. The diameter of the protective wheel 17 is slightly larger than the thickness of the second blade 13, ensuring that when the second blade 13 is in contact with the well wall, the protective wheel 17 contacts the well wall first and rolls, while a stable scraping gap is maintained between the scraping edge of the second blade 13 and the well wall.

[0032] An elastic reset element 14 is connected between the upper end of the second blade 13 and the outer wall of the outer rotating tube 6. The elastic reset element 14 is preferably a tension spring. In its natural state, the tension spring maintains a certain preload, pulling the second blade 13 towards the outer wall of the outer rotating tube 6, causing the second rotary cutter 12 to retract in its non-working state. When the outer rotating tube 6 rotates at high speed, centrifugal force overcomes the tension spring, causing the second blade 13 to open outwards around the hinge point, achieving adaptive expansion. The stiffness of the tension spring should be designed to match the rated speed of the device and the blade mass, ensuring that the second blade 13 can open to the required extent to fit against the well wall at the rated operating speed.

[0033] The lower cutting section includes a first rotary cutter 10, a first blade 11, a shearing blade 15, and a water outlet 16. The first rotary cutter 10 is fixedly connected to the bottom end of the inner rotating pipe 3. The first rotary cutter 10 is connected to the bottom end of the inner rotating pipe 3 through a connecting port located in its middle. The connecting port and the inner rotating pipe 3 are fixed by a threaded connection or a snap-fit ​​method. The bottom end of the inner rotating pipe 3 is fixedly connected to the connecting port by multiple connecting posts. The connecting posts are evenly distributed circumferentially, so that a flow gap is formed between the bottom end of the inner rotating pipe 3 and the first rotary cutter 10, allowing high-pressure water to pass through.

[0034] The first rotary cutter 10 includes a plurality of circumferentially distributed first blades 11. The upper and lower edges of the first blades 11 are both sharpened, forming a double-sided cutting edge. The lower cutting edge is used to break up the slab-like sediment layer at the bottom of the well in an axial downward direction, while the upper cutting edge is used to cooperate with the shearing blade 15 to achieve the shearing and anti-entanglement function.

[0035] The shearing blade 15 is fixedly mounted at the bottom end of the outer rotating tube 6. Multiple shearing blades 15 are arranged circumferentially along the bottom end of the outer rotating tube 6. The shearing blade 15 is located above the rotation trajectory of the first blade 11, and there is an interlaced shearing gap between it and the upper cutting edge of the first blade 11. Preferably, the cutting edge of the shearing blade 15 forms a relative inclined angle with the upper cutting edge of the first blade 11 to produce a sliding shearing effect and improve the cutting ability.

[0036] like Figure 4 As shown, the bottom end of the outer rotating pipe 6 is an arc-shaped closed structure. Multiple outlets 16 are circumferentially spaced on the side wall near the bottom of the outer rotating pipe 6, with the openings of the outlets 16 angled upwards. The high-pressure water flowing through the second flow channel continues to flow downwards after impacting the second turbine blades 9. Upon reaching the bottom of the outer rotating pipe 6, it smoothly changes direction via the arc-shaped bottom surface and is sprayed obliquely upwards from the outlets 16 into the annular gap between the outer rotating pipe 6 and the well wall. This arc-shaped bottom surface, combined with the angled outlets 16, ensures smooth flow and minimal pressure loss of the high-pressure water during the turning process, and the jet direction is clearly directed towards the bottom of the annulus, effectively carrying sludge upwards.

[0037] High-pressure water is pumped from the surface high-pressure water pump to the drill pipe cavity, and then flows downwards into the connecting section 1. Upon entering the connecting section 1, the high-pressure water encounters the conical guide structure at the top of the splitter pipe 2, and is smoothly split into two paths. The first path: the high-pressure water enters the interior of the splitter pipe 2 and flows downwards along the interior of the inner rotating pipe 3. As it flows past the first turbine blade 5, it impacts the blade, generating work and driving the inner rotating pipe 3 to rotate in the first direction. Subsequently, the high-pressure water continues downwards and is ejected through the gap between the connecting columns at the bottom of the inner rotating pipe 3, acting on the sediment layer at the bottom of the well. The second path: the high-pressure water flows downwards through the annular splitting gap between the outer wall of the splitter pipe 2 and the inner wall of the connecting section 1, entering the annular gap between the outer wall of the splitter pipe 2 and the inner wall of the outer rotating pipe 6. As it flows past the second turbine blade 9, it impacts the blade, generating work and driving the outer rotating pipe 6 to rotate in the second direction. The high-pressure water then continues downward, turns at the arc-shaped closed bottom of the outer rotating pipe 6, and sprays obliquely upward from the outlet 16 on the side wall of the outer rotating pipe 6, entering the annular gap between the outer wall of the outer rotating pipe 6 and the well wall, carrying the sludge upward.

[0038] The first and second flow channels are completely physically isolated inside the device and do not cross-flow. After the two water flows converge in the bottom area of ​​the well, they carry the broken sludge upwards through the annulus between the outer wall of the outer pipe 6 and the well wall and return to the wellhead.

[0039] Combination Figure 1-4 As shown, the operation method of the high-efficiency rotary cutting dredging device for deep water wells of the present invention includes: Step 1: Lowering the device Tighten the inner thread on the top of connecting section 1 to the outer thread at the bottom of the drill pipe to ensure a secure and reliable seal. Lift the device using the drilling rig, align it with the wellhead, and slowly lower it into the deep well. During lowering, since the outer rotating pipe 6 does not rotate, the second rotary cutter 12 remains retracted under the preload of the elastic reset element 14 (tension spring), minimizing the overall outer diameter of the device and allowing it to pass smoothly through the narrow sections of the wellhead and wellbore. When the device reaches above the sediment layer at the bottom of the well, stop lowering and prepare for operation.

[0040] Step 2: Introduce high-pressure water to drive the inner and outer rotating pipes 6 to rotate in opposite directions. The ground high-pressure water pump is started, and high-pressure water is introduced into the connecting section 1 through the drill pipe. After flowing into the connecting section 1, the high-pressure water is smoothly diverted by the conical guide structure at the top of the diverter pipe 2, entering the first flow channel inside the inner rotating pipe 3 and the second flow channel between the outer wall of the diverter pipe 2 and the inner wall of the outer rotating pipe 6. The high-pressure water in the first flow channel impacts the first turbine blade 5, driving the inner rotating pipe 3 to rotate in the first direction; the high-pressure water in the second flow channel impacts the second turbine blade 9, driving the outer rotating pipe 6 to rotate in the second direction, which is opposite to the first direction. Since the first turbine blade 5 and the second turbine blade 9 rotate in opposite directions, and the inner rotating pipe 3 and the outer rotating pipe 6 rotate in opposite directions, the counter-torques generated by them cancel each other out on the stationary component of the diverter pipe 2, resulting in a low net torque transmitted to the top drill pipe, and the drill pipe does not twist.

[0041] Step 3: Rotary cutting and adaptive scraping The first rotary cutter 10 rotates at high speed under the drive of the inner rotating tube 3, and the lower edge of the first blade 11 cuts and breaks up the hardened sediment at the bottom of the well. The shearing force generated by the first blade 11 during rotation breaks the hardened sediment layer into fragments.

[0042] Simultaneously, the outer rotating tube 6 rotates at high speed, generating centrifugal force. This centrifugal force acts on the second rotary cutter 12. When the centrifugal force exceeds the preload of the elastic reset element 14 (tension spring), the second blade 13 opens outward around the hinge point. The higher the rotational speed of the device, the greater the centrifugal force, and the greater the opening amplitude of the second blade 13, allowing the protective wheel 17 at the end of the second blade 13 to tightly adhere to well walls of different diameters. The scraping edges on the second blade 13 perform circumferential scraping and cleaning of the deposits on the well wall.

[0043] Step 4: Friction Reduction and Protection of Protective Wheel 17 During the rotation of the second blade 13 against the well wall, the protective wheel 17 at the end of the second blade 13 rolls against the well wall. The protective wheel 17 converts the sliding friction between the second blade 13 and the well wall into rolling friction, reducing the frictional resistance when the second rotary cutter 12 rotates and scrapes, and reducing the rotational energy consumption of the outer rotating tube 6. At the same time, when there are hard rock layers or protrusions on the well wall, the protective wheel 17 first contacts and rolls over the obstacle, forming a physical isolation layer between the second blade 13 and the hard well wall, preventing the scraping edge of the second blade 13 from directly impacting the hard object and causing chipping or breakage.

[0044] Step 5: Interlaced cutting to prevent tangling During the rotation and crushing process of the first rotary cutter 10, fibrous debris such as tree roots, ropes, and plastic bags at the bottom of the deep well may become entangled on the first blade 11 by the water flow. Because the upper edge of the first blade 11 has an open-blade structure, and the shearing blade 15 is fixedly installed at the bottom of the outer rotating pipe 6, above the rotation trajectory of the first blade 11, there is an alternating shearing gap between the cutting edge of the shearing blade 15 and the upper cutting edge of the first blade 11. When the first blade 11 rotates in the first direction, its upper cutting edge moves relative to the cutting edge of the shearing blade 15. Fiber debris entangled at the root of the first blade 11 is carried into this shearing gap during rotation and is cut off by the alternating shearing action of the upper cutting edge of the first blade 11 and the cutting edge of the shearing blade 15. The cut fragments are washed away by the high-pressure water flow and cannot continue to entangle, thus preventing drill jamming and torque overload from the source.

[0045] Step Six: High-Pressure Water Assisted Slag Removal The high-pressure water flowing through the second flow channel continues to flow downwards after impacting the second turbine blade 9. Upon reaching the bottom of the outer rotating pipe 6, it smoothly changes direction via the arc-shaped closed bottom surface and is sprayed obliquely upwards from the outlet 16 on the side wall of the outer rotating pipe 6 into the annular gap between the outer rotating pipe 6 and the well wall. This obliquely upward jet will cause the sludge and debris generated by the rotary shearing to surge upwards and suspend, preventing the heavier gravel from settling again at the bottom of the well. At the same time, the high-pressure water flowing through the first flow channel is ejected from the nozzles on the end face and side wall of the first blade 11, forming a turbulent water flow at the bottom of the well, which disperses the sludge and pushes it into the annular region.

[0046] Step 7: Negative pressure forced suction to remove slag While high-pressure water assists in slag removal, the ground negative pressure suction equipment is activated to create negative pressure at the top of the annulus between the outer rotating pipe 6 and the well wall. This negative pressure forces the slag-water mixture in the annulus to be drawn in, working in conjunction with the carrying effect of the high-pressure water jet upwards to create a synergistic slag removal effect of "pushing down and pulling up". The slag-water mixture flows continuously upwards along the annular gap between the outer wall of the outer rotating pipe 6 and the well wall, and is discharged from the wellhead to the ground sedimentation tank for mud-water separation. After the sludge at the bottom of the well is cleaned and the discharged water becomes clear, the high-pressure water pump and the negative pressure suction equipment are turned off, the outer rotating pipe 6 stops rotating, and the second rotary cutter 12 automatically retracts under the pulling force of the elastic reset member 14. The device is then pulled out of the well by the drilling rig, completing the sludge removal operation.

[0047] It is understood that the present invention has been described through some embodiments, and those skilled in the art will recognize that various changes or equivalent substitutions can be made to these features and embodiments without departing from the spirit and scope of the invention. Furthermore, under the teachings of the present invention, these features and embodiments can be modified to adapt to specific situations and materials without departing from the spirit and scope of the invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are within the protection scope of the present invention.

Claims

1. A high-efficiency rotary cutting dredging device for deep water wells, characterized in that, include: The connecting section (1) has a threaded connection structure for connecting the drill rod on its top inner wall, and a high-pressure water flow channel is formed inside the connecting section (1). The diversion pipe (2) is fixedly installed below the connecting section (1). The top end of the diversion pipe (2) extends into the interior of the connecting section (1), and an annular diversion gap is formed between the outer wall of the diversion pipe (2) and the inner wall of the connecting section (1). The inner rotating tube (3) is rotatably disposed inside the split tube (2). The upper and lower ends of the inner rotating tube (3) are rotatably engaged with the split tube (2) through the first bearing (4). Multiple first turbine blades (5) are arranged circumferentially on the inner wall of the inner rotating tube (3). The outer rotating pipe (6) is rotatably disposed outside the diverter pipe (2). The upper end of the outer rotating pipe (6) is rotatably connected to the lower end of the connecting section (1) through the second bearing (7). The lower end of the outer rotating pipe (6) is rotatably connected to the lower end of the diverter pipe (2) through the third bearing (8). The inner wall of the outer rotating pipe (6) is circumferentially provided with multiple second turbine blades (9). The rotation direction of the second turbine blades (9) is opposite to that of the first turbine blade (5). The first rotary cutter (10) is fixedly connected to the bottom end of the inner rotating tube (3). The first rotary cutter (10) includes a plurality of first blades (11) evenly distributed in the circumference. Multiple second rotary cutters (12) are equidistantly hinged on the outer wall of the outer rotating tube (6). Each second rotary cutter (12) includes a second blade (13), and an elastic reset member (14) is connected between the upper end of the second blade (13) and the outer wall of the outer rotating tube (6). The shearing blade (15) is fixedly installed at the bottom end of the outer rotating tube (6). The shearing blade (15) is located on the upper side of the rotation trajectory of the first blade (11) and forms a shearing engagement with the upper side edge of the first blade (11). After the high-pressure water flows into the connecting section (1), it is divided by the diversion pipe (2) into a first flow channel that flows through the inner rotating pipe (3) and a second flow channel that flows through the annular diversion gap between the diversion pipe (2) and the outer rotating pipe (6). The first flow channel impacts the first turbine blade (5) and drives the inner rotating pipe (3) to drive the first rotary cutter (10) to rotate in the first direction. The second flow channel impacts the second turbine blade (9) and drives the outer rotating pipe (6) to drive multiple second rotary cutters (12) and shearing blades (15) to rotate in the second direction. The first direction is opposite to the second direction.

2. The high-efficiency rotary cutting dredging device for deep water wells according to claim 1, characterized in that, The outer wall of the diversion pipe (2) and the inner wall of the connecting section (1) are fixedly connected by multiple support columns.

3. The high-efficiency rotary cutting dredging device for deep water wells according to claim 1, characterized in that, The bottom end of the outer rotating pipe (6) is an arc-shaped closed structure. Multiple water outlets (16) are equidistantly opened on the side wall near the bottom end of the outer rotating pipe (6). The opening direction of the water outlets (16) is inclined upward. After the high-pressure water flowing through the second flow channel turns through the arc-shaped surface at the bottom end of the outer rotating pipe (6), it is discharged obliquely upward from the water outlets (16) to the space between the outer rotating pipe (6) and the well wall.

4. The high-efficiency rotary cutting dredging device for deep water wells according to claim 1, characterized in that, The top of the diverter (2) is a tapered flow guide structure.

5. The high-efficiency rotary cutting dredging device for deep water wells according to claim 1, characterized in that, The upper and lower edges of the first blade (11) are both sharpened; multiple shearing blades (15) are arranged circumferentially along the bottom end of the outer rotating tube (6), and there is an interlaced shearing gap between the cutting edge of the shearing blade (15) and the upper cutting edge of the first blade (11).

6. The high-efficiency rotary cutting dredging device for deep water wells according to claim 1, characterized in that, The first rotary cutter (10) is connected to the bottom end of the inner rotating tube (3) through the connection port set in the middle. The connection port and the inner rotating tube (3) are fixed by threaded connection or snap-fit. The bottom end of the inner rotating tube (3) and the connection port are fixedly connected by multiple connecting posts.

7. The high-efficiency rotary cutting dredging device for deep water wells according to claim 1, characterized in that, The hinge point of the second rotary cutter (12) is located at the lower end of the outer wall of the outer rotating tube (6), and the second blade (13) extends outward from the hinge point; the elastic reset member (14) is a tension spring, one end of which is connected to the second blade (13) and the other end is connected to the outer wall of the outer rotating tube (6).

8. The high-efficiency rotary cutting dredging device for deep water wells according to claim 7, characterized in that, The end of the second blade (13) is provided with a protective wheel (17). The protective wheel (17) is used to reduce frictional resistance when the second blade (13) is in contact with the well wall, and at the same time prevent the second blade (13) from being damaged due to direct contact with the hard well wall.

9. The operating method of the high-efficiency rotary cutting dredging device for deep water wells according to any one of claims 1 to 8, characterized in that, Includes the following steps: S1: Fix the connecting section (1) to the drill pipe and lower the device to the bottom silt layer of the deep water well; S2: High-pressure water is introduced into the connecting section (1) through the drill rod. After the high-pressure water is smoothly diverted by the conical guide structure at the top of the diversion pipe (2), it enters the first flow channel inside the inner rotating pipe (3) and the second flow channel between the outer wall of the diversion pipe (2) and the inner wall of the outer rotating pipe (6), driving the inner rotating pipe (3) and the outer rotating pipe (6) to rotate in opposite directions. S3: The first rotary cutter (10) is driven by the inner rotating pipe (3) to cut and break up the sludge deposits at the bottom of the well. At the same time, the centrifugal force generated by the rotation of the outer rotating pipe (6) causes the second rotary cutter (12) hinged on the outer wall of the outer rotating pipe (6) to open outward against the tension of the elastic reset member (14), so that the second blade (13) fits tightly against the well wall of different diameters and performs adaptive scraping and cleaning of the deposits on the well wall. S4: The protective wheel (17) at the end of the second blade (13) rolls against the well wall during the scraping process, converting sliding friction into rolling friction to reduce rotational resistance. At the same time, the protective wheel (17) forms a physical isolation layer between the second blade (13) and the hard well wall to prevent the second blade (13) from chipping or breaking due to direct contact with hard rock layers or well wall protrusions. S5: During the rotary cutting process, the shearing blade (15) and the rotating first blade (11) form an interlaced shearing action to cut off one or more of the fibrous debris such as tree roots, ropes, and plastic bags wrapped around the first blade (11); S6: The high-pressure water flowing through the second flow channel continues to flow downward after impacting the second turbine blade (9) and doing work. After turning at the bottom arc surface of the outer rotating pipe (6), it is sprayed obliquely upward from the outlet (16) on the side wall of the outer rotating pipe (6) to the space between the outer rotating pipe (6) and the well wall, carrying the broken sludge upward. S7: Start the ground negative pressure suction equipment to form a negative pressure at the top of the annulus between the outer rotating pipe (6) and the well wall, and force the sludge-water mixture in the annulus to be suctioned. Together with the high pressure water carrying effect, the sludge at the bottom of the well is continuously discharged from the wellhead to complete the sludge removal operation.

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