Guiding device for a shaft drill and drill head

Abstract

The application provides a guide device for a shaft drilling machine and a drill bit, wherein the guide device comprises a guide body, at least two guide rollers mounted on the side of the guide body, mounting parts arranged at the axial ends of the guide body for mounting upper drilling tools and lower drilling tools, and mounting seats arranged in the middle of the guide body for mounting the guide rollers; the guide rollers are arranged in a central symmetry with the guide body, and the distance between the guide rollers and the guide body is less than the radial dimension of the guide rollers. The guide device for the shaft drilling machine has a compact and symmetrical overall structure, and improves the stability during the working of the guide device, the service life, and the efficiency of construction.

Description

Technical Field

[0001] This application relates to the field of tunneling equipment technology, and more particularly to a guiding device and drill bit for a vertical shaft drilling rig. Background Technology

[0002] In hard rock formations, underground mineral resource extraction or underground space development and utilization operations generally employ vertical shaft drilling for mechanical excavation. The drilling method provides power to the vertical shaft drilling rig on the surface, while the drill bit below performs drilling. The drill bit mainly includes a cutterhead and a guiding device. The guiding device counteracts the radial sway and radial force generated during cutterhead drilling, ensuring the cutterhead remains in a cylindrical constrained state during operation and guaranteeing the verticality of the borehole.

[0003] Traditional guiding devices include shoe-type guiding devices and guide roller-type guiding devices. Among them, the guide roller-type guiding device has a fixed central cylinder in the middle and multiple guide rollers evenly distributed on the outer periphery. Moreover, the guide roller-type guiding device has advantages such as good guiding function, directional control and low friction, and is widely used in mining operations.

[0004] Chinese patent (CN 220979377 U) discloses a self-lubricating guide device, including an installation body, a guide structure, at least one bearing installation structure, a variable diameter structure, etc. However, the design of this self-lubricating guide device has the risk of poor stability due to its high center of gravity.

[0005] In view of this, it is necessary to design a guiding device and drill bit for vertical shaft drilling rigs to solve one of the above problems. Summary of the Invention

[0006] This application provides a guiding device and drill bit for a vertical shaft drilling rig. By using the guiding device for a vertical shaft drilling rig of this application, the stability of the guiding device during operation can be improved, the service life of the guiding device can be increased, and the construction efficiency can be improved.

[0007] To achieve the above objectives, the technical solution provided in this application is as follows:

[0008] This application provides a guiding device for a vertical shaft drilling rig. The guiding device includes: a guiding body and at least two guide rollers installed on the side of the guiding body; mounting portions located at both ends of the guiding body along the axial direction for mounting an upper drilling tool and a lower drilling tool; and a mounting seat located in the middle of the guiding body for mounting the guide rollers. The guide rollers are arranged symmetrically about the guiding body, and the distance between the guide rollers and the guiding body is less than the radial dimension of the guide rollers.

[0009] Furthermore, the axial dimension of the guide roller is not greater than the distance between the guide roller and the mounting portion.

[0010] Furthermore, in the radial direction of the guide body, the edge of the guide roller extends beyond the edge of the guide body.

[0011] Furthermore, the mounting base includes a fixing part fixed to the side of the guide body and a connecting part fixedly connected to the fixing part. The mounting base is T-shaped, and the connecting part is provided with mounting holes for mounting the guide roller so that the guide roller is spaced apart from the guide body.

[0012] Furthermore, the guiding device also includes a slag discharge channel that runs through the guiding body along the axial direction and a high-pressure air chamber located outside the slag discharge channel, wherein the distance between the high-pressure air chamber and the slag discharge channel is not greater than the diameter of the high-pressure air chamber.

[0013] Furthermore, the guiding device also includes a receiving cavity located outside the high-pressure gas chamber, a counterweight ring disposed in the receiving cavity, and a cover plate for sealing the receiving cavity, wherein the radial dimension of the counterweight ring is larger than the diameter of the slag discharge channel.

[0014] Furthermore, the axial dimension of the mounting portion is greater than the thickness of the cover plate.

[0015] Furthermore, the guide roller includes an installation structure, an outer cylinder structure sleeved on the outside of the installation structure, and at least one bearing structure for rotatably connecting the installation structure and the outer cylinder structure. The installation structure is provided with a connected lubrication cavity and a grease compensation cavity. The bearing structure is installed in the lubrication cavity. The guide roller also includes a pressure balancing structure disposed in the grease compensation cavity to apply pressure to the bottom wall of the compensation cavity away from the lubrication cavity, so that the internal pressure of the compensation cavity is not less than the external pressure.

[0016] Furthermore, the pressure balancing structure includes a piston that is in a sealing sliding fit with the compensation cavity, and an elastic element connected to the side of the piston away from the lubrication cavity, the elastic element being in a compressed state.

[0017] This application also provides a drill bit for a vertical shaft drilling rig, the drill bit including the aforementioned guiding device for a vertical shaft drilling rig.

[0018] Compared with related technologies, the beneficial effects of this application are as follows: the guiding device for vertical shaft drilling rigs using the present application has a compact and symmetrical overall structure, which improves the stability, service life and construction efficiency of the guiding device during operation. Attached Figure Description

[0019] Figure 1 This is a cross-sectional view of a guide device according to one embodiment of the guide device for a vertical shaft drilling rig in this application.

[0020] Figure 2 yes Figure 1 Enlarged view of the local structure at point A in the middle.

[0021] Figure 3 yes Figure 1 Cross-sectional view of the middle guide roller.

[0022] Figure 4 yes Figure 3 Enlarged view of the local structure at point B in the middle.

[0023] Figure 5 yes Figure 3 Enlarged view of the local structure at point C.

[0024] Figure 6 This is a cross-sectional view of a drill bit according to one embodiment of the drill bit in this application.

[0025] Figure 7 yes Figure 6 Bottom view of the middle cutter head assembly.

[0026] Figure 8 yes Figure 6 Side view of the central fixing component.

[0027] Among them, 10-guide device, 101-guide body, 102-guide roller, 1-mounting structure, 11-mounting shaft, 12-lubrication cavity, 13-cover, 131-oil injection hole, 132-hole plug, 141-first sealing ring, 142-second sealing ring, 15-floating plug, 16-compensation cavity, 17-plug, 171-elastic ring, 18-retaining ring, 181-fixed ring, 182-adjusting ring, 2-outer cylinder structure, 21-tooth insert, 3-bearing structure, 31-first bearing, 32-second bearing, 4-pressure balance structure, 41-piston, 42-elastic element, 43-sealing ring, 103-mounting part, 1031-first mounting hole, 1032-second mounting hole, 104-mounting seat, 1041-fixed part, 1042-connector 105-Reinforcing rib, 106-Slag discharge channel, 1061-Slag discharge bend, 1062-Mixing air hole, 107-High pressure air chamber, 108-Counterweight ring, 109-Cover plate, 1091-Clamping block, 20-Cutterhead assembly, 201-Base plate, 2011-Base plate body, 2012-Mounting groove, 202-Cutter, 2021-Center hob, 2022-Inner ring cutter, 2023-First cutter, 2024-Second cutter, 2025-Third cutter, 2026-Fourth cutter, 203-Fixing device, 204-Counterweight cavity, 205-Stop block, 206-Return slurry port, 20-Ring plate, 30-Connecting device, 40-Fixing component, 41-Wing plate, 42-Body plate, 50-Transition module, 51-Internal hexagonal toothed connector. Detailed Implementation

[0028] To enable those skilled in the art to better understand the technical solutions in this application, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this application.

[0029] It should be noted that the terms "upper" and "lower," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the purpose of simplifying the description of this application and do not indicate or imply that the device referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limiting the scope of protection of this application. Specifically, in this application, the direction facing the ground is referred to as "lower," and conversely, the direction away from the ground is referred to as "upper." Other descriptions of orientation are defined based on "upper" and "lower."

[0030] In the various figures of this application, for ease of illustration, certain dimensions of structures or parts may be exaggerated relative to other structural parts; therefore, they are only used to illustrate the basic structure of the subject matter of this application.

[0031] This application provides a guiding device 10 and a drill bit for a vertical shaft drilling rig, such as Figures 1 to 8 As shown, the guide device 10 is an important component of the drill bit. During the drilling process, the guide device 10 plays a guiding role to ensure that the drill bit's path is straight. Moreover, the guide device 10 can also counteract the radial wobble and radial force generated by the drill bit's cutterhead, thereby improving the drill bit's stability and service life.

[0032] like Figure 1 As shown, the guiding device 10 includes a guiding body 101 and at least two guide rollers 102 mounted on the side of the guiding body 101, mounting portions 103 located at both ends of the guiding body 101 along the axial direction for mounting an upper drilling tool and a lower drilling tool, and a mounting seat 104 located in the middle of the guiding body 103 for mounting the guide rollers 102. The guide rollers 102 are arranged symmetrically about the guiding body 101, and the distance between the guide rollers 102 and the guiding body 101 is less than the radial dimension of the guide rollers 102, making the overall structure of the guiding device 10 more compact, with its center of gravity located in the center, thus improving the stability and service life of the guiding device 10.

[0033] The mounting portion 103 is fixed to both ends of the guide body 101 along the axial direction. The mounting portion 103 is symmetrically arranged on the side of the guide body 101 relative to the axial direction of the guide body 101. The mounting portion 103 on one side of the guide body 101 is provided with a first mounting hole 1031, and the mounting portion 103 on the other side of the guide body 101 is provided with a second mounting hole 1032. The inner diameter of the first mounting hole 1031 is the same, while the inner diameter of the second mounting hole 1032 is different and is provided with a step. That is, the guide device 10 is fixed with different bolts.

[0034] Furthermore, the mounting base 104 includes a fixing part 1041 fixed to the side of the guide body 101 and a connecting part 1042 fixedly connected to the fixing part 1041. The fixing part 1041 extends axially along the guide device 10, and the connecting part 1042 extends radially along the guide device 10. The connecting part 1042 is provided with a mounting hole for mounting the guide roller 102 so that the guide roller 102 is spaced apart from the guide body 101.

[0035] In this embodiment, the mounting base 104 is T-shaped, and the thickness of the fixing part 1041 is greater than the thickness of the connecting part 1042. During the construction process, when the drill bit is lowered and pulled out, the guide roller 102 is able to withstand a large axial load, thereby improving the stability of the guiding device 10 during the drill bit's drilling process.

[0036] In this application, the axial dimension of the guide roller 102 is not greater than the distance between the guide roller 102 and the mounting part 103, and the volume of the guide roller 102 is moderate, which improves the stability of the guide roller 102 during rotation.

[0037] In the radial direction of the guide body 101, the edge of the guide roller 102 extends beyond the edge of the guide body 101, so that the outer cylinder structure 2 of the guide roller 102 contacts the well wall. The friction between the outer cylinder structure 2 and the well wall drives the outer cylinder structure 2 to rotate, reducing the resistance between the guide roller 102 and the well wall, thereby reducing the torque when the guide device 10 rotates.

[0038] In this embodiment, six guide rollers are provided, which are equally spaced along the circumference of the guide body 101 on the side of the guide body 101.

[0039] Specifically, such as Figures 3 to 5As shown, the guide roller 102 includes an installation structure 1 for fixing the guide roller 102 to other components, an outer cylinder structure 2, at least one bearing structure 3 for rotatably connecting the installation structure 2 and the outer cylinder structure 2, and a pressure balancing structure 4 disposed inside the installation structure 2. The above structures cooperate with each other to prevent external mud from entering the interior of the installation structure 2, avoid the risk of the interior of the installation structure 2 being contaminated or even corroded by mud, reduce maintenance costs, and improve construction efficiency.

[0040] For ease of understanding and description, the axial direction of the mounting structure 1 and the outer cylinder structure 2 is defined as the length direction of the guide roller 102, that is, it is the same as the axial direction of the guide roller 102, and other directions are set to correspond to the axial direction.

[0041] Part of the mounting structure 1 is located inside the outer cylinder structure 2. Specifically, the mounting structure 1 includes a mounting shaft 11, which extends axially. The middle part of the mounting shaft 11 is located inside the outer cylinder structure 2. The axial length of the mounting shaft 11 extends beyond the outer cylinder structure 2. The guide roller 102 is mounted on other structures of the guiding device 10 using the mounting shaft 11.

[0042] The mounting structure 11 is provided with a lubrication cavity 12 for accommodating the bearing structure 3. The lubrication cavity 12 extends axially and is located on the side of the mounting shaft 11. Preferably, the lubrication cavity 12 is formed between the mounting shaft 11 and the outer cylinder structure 2, so that the bearing structure 3 can cooperate with the outer cylinder structure 2 and the mounting structure 1 respectively.

[0043] like Figure 5 As shown, the installation structure 1 also includes a cover 13 for covering the end of the lubrication cavity 12, an oil injection hole 131 penetrating the cover 13 to connect the inside and outside of the lubrication cavity 12, and a plug 132 for sealing the oil injection hole 131. During the initial installation stage of the guide roller 102 and the subsequent maintenance stage, grease is injected into the lubrication cavity 12 through the oil injection hole 131, and the oil injection hole 131 is sealed by the plug 132. In this embodiment, the plug 132 is a bolt plug, which is convenient for installation and disassembly, and will not fall off due to construction vibration.

[0044] Among them, the cover 13, which is far away from the pressure balance structure 4, is connected to the mounting shaft 11 by a thread, ensuring that the bearing structure 3 is always in a compressed state, and the entire guide roller 102 structure is stable and reliable.

[0045] To prevent grease leakage from the lubrication chamber 12, the mounting structure 1 further includes a first sealing ring 141 for sealing the mounting shaft 11 and the cover 13, a second sealing ring 142 for sealing the bearing structure 3 and the cover 13, and a floating plug 15 disposed between the bearing structure 3 and the cover 13, thereby improving the sealing performance of the lubrication chamber 12. Furthermore, the floating plug 15 reduces the sealing resistance of the lubrication chamber 12, allowing the outer cylinder structure 2 to rotate easily. Consequently, the starting torque of the guide roller 102 is low. When the drill bit rotates, the guide roller 102 is in a state of revolution and rotation, which reduces the friction and resistance between the guide roller 102 and the well wall, thus minimizing the loss of drill bit torque.

[0046] The mounting structure 1 is also provided with a compensation cavity 16 connected to the lubrication cavity 12. One end of the compensation cavity 16 along the axial direction of the mounting structure 1 is connected to the external environment, and the other end of the compensation cavity 16 is connected to the lubrication cavity 12. When there is a lot of grease in the lubrication cavity 12, the excess grease enters the compensation cavity 16. When more grease is needed in the lubrication cavity 12, the grease flows from the compensation cavity 16 into the lubrication cavity 12 to lubricate the bearing structure 3.

[0047] like Figure 4 As shown, the installation structure 1 also includes a plug 17 for sealing the compensation cavity 16 and an elastic ring 171 that is sleeved on the outside of the plug 17 and has an interference fit with the inner wall of the compensation cavity 16. The elastic ring 171 can be used to seal the compensation cavity 16 on the one hand, and on the other hand, the elastic ring 171 is sleeved on the outside of the plug 17 to stop the plug 17 and ensure that the plug 17 will not fall out of the compensation cavity 16 during construction vibration.

[0048] To fix and limit the position of the elastic ring 171, the outer wall of the plug 17 and / or the inner wall of the compensation cavity 16 are provided with a receiving groove for accommodating the elastic ring 171. The elastic ring 171 protrudes from the receiving groove, which facilitates an interference fit between the elastic ring 171 and the inner wall of the compensation cavity 16 or the outer wall of the plug 17. In this embodiment, the receiving groove is located on the inner wall of the compensation cavity 16.

[0049] Furthermore, the outer cylinder structure 2 is sleeved on the outside of the mounting shaft 11 and abuts against the cover 13. That is, the outer cylinder structure 2 rotates relative to the mounting structure 1 in the circumferential direction under the action of external force.

[0050] In this embodiment, the axial end of the outer cylinder structure 2 abuts against the cover 13, increasing the contact area between the outer cylinder structure 2 and the mounting structure 1, and improving the stability of the outer cylinder structure 2 during rotation.

[0051] In this embodiment, the outer side of the outer cylinder structure 2 is in contact with the well wall. While the guide roller 102 rotates relative to the guide device 10, the outer cylinder structure 2 is subjected to the frictional force of the well wall, thereby driving the outer cylinder structure 2 to rotate relative to the mounting structure 1, that is, the guide roller 102 rotates along its axial direction.

[0052] The outer cylinder structure 2 is provided with a plurality of insert teeth 21 on its outer side. When the outer cylinder structure 2 comes into contact with the well wall, the insert teeth 21 increase the friction between the outer cylinder structure 2 and the well wall, thereby driving the outer cylinder structure 2 to rotate.

[0053] In this embodiment, a protective film is provided on the outer side of the outer cylinder structure 2. The thickness of the protective film is not less than 2mm. The protective film is made by nitriding process. The setting of the protective film can effectively extend the service life of the guide roller.

[0054] The bearing structure 3 is disposed within the lubrication cavity 12. The grease within the lubrication cavity 12 lubricates the rotation of the bearing structure 3, reducing the rotational torque of the outer cylinder structure 2. The outer cylinder structure 2 is rotatably connected to the mounting structure 1 via the bearing structure 3. Specifically, the inner ring of the bearing structure 3 abuts against the mounting shaft 11, and the outer ring of the bearing structure 3 abuts against the inner side of the outer cylinder structure 2, thereby assisting the outer cylinder structure 2 in rotating relative to the mounting structure 1.

[0055] The guide roller 102 of this application includes a plurality of bearing structures 3 arranged circumferentially along the central axis 11. The bearing structure 3 includes a bearing disposed in the lubrication cavity 12. The inner ring of the bearing abuts against the mounting shaft 11, and the outer ring of the bearing abuts against the inner side of the outer cylinder structure 2.

[0056] In this embodiment, the mounting structure 1 further includes a retaining ring 18 disposed on the outside of the mounting shaft 11 to fix the bearing. The retaining ring 18 includes a fixing ring 181 and an adjusting ring 182 that abuts against the inner ring of the bearing and the fixing ring 181 respectively. The length of the fixing ring 181 along the axial direction of the mounting shaft 11 is greater than the length of the adjusting ring 182, and the thickness of the fixing ring 181 along the radial direction of the mounting shaft 11 is greater than the thickness of the adjusting ring 182. The fixing ring 181 is easier to fit with the mounting shaft 11. The adjusting ring 182 is used to adjust the angle of the bearing structure 3 to avoid stress concentration and over-constraint, making the structure more reasonably stressed, and reducing the processing difficulty and processing cost of the retaining ring 18.

[0057] The bearing includes a first bearing 31 and a second bearing 32 located at both ends of the lubrication cavity 12. The first bearing 31 and the second bearing 32 are symmetrically arranged about the center of the axial direction of the mounting structure 1, so that the bearings can be subjected to forces in both directions, ensuring that the guide roller 102 can withstand very large axial loads. Moreover, the center of gravity of the guide roller 102 is located in the center position, which improves the stability of the guide roller 102 during rotation.

[0058] The bearings used in this application adopt a double thrust bearing structure, which can prevent the guide roller 102 from being damaged by the external force of the well wall and falling rock blocks when lowering and pulling out the drill string.

[0059] like Figure 4 As shown, the pressure balancing structure 4 is located inside the compensation cavity 16 and applies pressure to the bottom wall of the compensation cavity 16 away from the lubrication cavity 12, so that the internal pressure of the compensation cavity 16 is not less than the external pressure, thus preventing mud from entering the lubrication cavity 12 through the compensation cavity 16, providing good protection for components such as bearings, and extending the service life of the guide roller 102.

[0060] Specifically, the pressure balancing structure 4 includes a piston 41 that is in a sealing and sliding fit with the compensation cavity 16, and an elastic element 42 connected to the side of the piston 41 away from the lubrication cavity 12. The other end of the elastic element 42 is connected to or abuts against the plug 17. When the elastic element 42 is in a compressed state, it applies pressure to the bottom wall of the compensation cavity 16 away from the lubrication cavity 12, thereby achieving the purpose of the internal pressure of the compensation cavity 16 being greater than the external pressure. In addition, the elastic element 42 indirectly applies pressure to the grease through the piston 41, so that the lubrication cavity 12 is filled with grease, which is beneficial to the lubrication of the bearing structure 3. At the same time, the floating plug 15 at the other end of the lubrication cavity 12 is squeezed, improving the sealing performance of the lubrication cavity 12. When the elastic element 42 gradually changes from a compressed state to a free state, the elastic element 42 pushes the piston 41, thereby pushing the grease in the compensation cavity 16 into the lubrication cavity 12.

[0061] In this embodiment, a sealing ring 43 is provided between the piston 41 and the compensation cavity 16 to improve the sealing performance of the compensation cavity 16.

[0062] The pressure balancing structure 4 can be replaced with elastic elements 42 of different specifications according to the depth of construction, generally one specification is applicable for 200 meters.

[0063] It is understood that the pressure balancing structure 4 can also be an elastic plug that undergoes elastic deformation under external force. The elastic plug is sealed and slidably connected to the compensation cavity 16. The pressure balancing structure in a compressed state can also achieve the purpose of applying pressure to the bottom wall of the compensation cavity 16, which is also within the protection scope of this application.

[0064] In this embodiment, the guiding device 10 further includes a reinforcing rib 105 disposed on the outside of the guiding body 101, and the mounting base 104 is fixed on the reinforcing rib 105.

[0065] Furthermore, such as Figure 2 As shown, the guiding device 10 further includes a slag discharge channel 106 extending axially through the guiding body 101 and a high-pressure air chamber 107 located outside the slag discharge channel 106. The distance between the high-pressure air chamber 107 and the slag discharge channel 106 is no greater than the diameter of the high-pressure air chamber 107. Gas is transported from the high-pressure air chamber 107 to the bottom of the guiding body 101 and mixes with the slurry to form a gas-liquid mixture. The gas-liquid mixture carries the drilling slag out of the well through the slag discharge channel 106. The design of the high-pressure air chamber 107 being close to the slag discharge channel 106 in this application facilitates the indirect carrying of slag out of the well by high-pressure gas.

[0066] The guiding device 10 also includes a receiving cavity located outside the high-pressure air chamber 107, a counterweight ring 108 disposed in the receiving cavity, and a cover plate 109 for sealing the receiving cavity. The design of the counterweight ring 108 can increase the weight of the guiding device 10, which can significantly increase the self-weight of the guiding device 10, thereby reducing the overall height of the drill bit.

[0067] In this embodiment, the radial dimension of the counterweight ring 108 is larger than the diameter of the slag discharge channel 106, thereby increasing the weight of the guide device 10 and improving the stability of the guide device 10.

[0068] like Figure 2 As shown, the cover plate 109 is inserted into the guide body 101. The end of the guide body 101 is provided with an insertion groove for receiving the cover plate 109, which facilitates the disassembly of the cover plate 109. In other words, the counterweight ring 108 can be disassembled. Construction personnel can replace the counterweight ring 108 with different weights according to different construction objects, thereby improving the adaptability of the guide device 10.

[0069] To prevent the cover plate 109 from falling off the guide body 101 during construction, the guide device 10 further includes a locking block 1091, which is engaged with the cover plate 109 and the guide body 101 to fix the cover plate 109 onto the guide body 101.

[0070] In this embodiment, the thickness of the cover plate 109 is not greater than the thickness of the mounting portion 103, that is, the axial dimension of the mounting portion 103 is greater than the thickness of the cover plate 109, thereby improving the structural strength of the guide device 10.

[0071] This application also provides a drill bit having the above-described guide device 10, such as... Figures 6 to 8As shown, this method is suitable for construction in hard rock formations. The drill bit is located at the lower end of the drill rod of the vertical shaft drilling rig, and the vertical shaft drilling rig controls the drill bit to perform drilling operations by controlling the drill rod.

[0072] The drill bit includes a cutterhead assembly 20 and at least one set of guide modules fixedly connected to the cutterhead assembly 20. The guide module includes a guide device 10 connected to the cutterhead assembly 20 and a connecting device 30 connected to the guide device 10. The drill bit also includes a transition module 50 fixedly connecting the guide module and the drill rod. The guide rollers 102 are symmetrically installed on the side of the guide device 10. In this application, the guide module is provided in three sets, and each guide device is provided with 6 guide rollers 102. The guide rollers 102 are arranged at intervals along the circumference of the guide device 10.

[0073] like Figure 6 As shown, the cutter head assembly 20 includes a base plate 201 and a cutter 202 mounted on the base plate 201. The base plate includes a base plate body 2011 and a mounting groove 2012 located in the middle of the base plate body 2011, so that cutters 202 with different mounting methods can be installed in the base plate body 2011 and the mounting groove 2012 respectively, and it can ensure that the horizontal segments of the trajectory lines of all cutters 202 are on the same plane.

[0074] Specifically, such as Figure 7 As shown, the cutting tool 202 includes a pair of central hobs 2021 located in the mounting groove 2012, a pair of inner ring cutting tools 2022 located outside the central hobs 2021, and several outer ring cutting tools. The central hobs 2021 are located close to the center of the base plate 201 and symmetrically arranged on both sides of the center. The central hobs 2021, inner ring cutting tools 2022, and several outer ring cutting tools are located on different radial directions of the base plate 201, and the horizontal segments of the trajectory lines of all cutting tools 202 are in the same plane. The layout and design of the cutting tools 202 of the drill bit in this application improves the rock-breaking efficiency of the drill bit, enhances the stability of the drill bit during rock breaking, and increases the lifespan of the drill bit.

[0075] For ease of description, the length direction of the drill bit is the axial direction, the extension direction of the base plate 201 is the circular plane, the arrangement direction of the pair of central hobs 2021 is the transverse direction, the direction perpendicular to the transverse direction is the longitudinal direction, the symmetrical point of the central hob 2021 is the dot of the base plate 201, and all other directions are based on this.

[0076] A pair of central roller cutters 2021 are spaced apart along a transverse diameter line. The central roller cutters 2021 are positive roller cutters, which facilitates the crushing of rocks near the center of the bottom plate 201.

[0077] A pair of inner ring cutters 2022 are located in the mounting groove 2012 and are respectively located on the outer side of a pair of central hobs 2021 along the vertical direction. That is, the inner ring cutters 2022 are centrally symmetrical about the center of the base plate 201. If the base plate 201 is divided into four quadrants, the pair of inner ring cutters 2022 are respectively located in the first quadrant and the third quadrant.

[0078] Both the center hob 2021 and the inner ring cutter 2022 are mounted on a saddle-type tool holder. Due to the height of the shoe-type tool holder, the center hob 2021 and the inner ring cutter 2022 are mounted in the mounting groove 2012 to ensure that the horizontal segments of the trajectory lines of the center hob 2021, the inner ring cutter 2022, and the outer ring cutter are all in the same plane.

[0079] The outer ring cutter is mounted on the base plate body 2011. The outer ring cutter includes a pair of first cutters 2023 adjacent to the central roller cutter 2021 and a pair of second cutters 2024 located outside the inner ring cutter 2022. The first cutters 2023 and the second cutters 2024 undertake the main rock-breaking task.

[0080] In the radial direction of the base plate 201, the radius of the circumference where the first cutter 2023 is located is smaller than the radius of the circumference where the second cutter 2024 is located. That is, the first cutter 2023 is closer to the center of the base plate 201 than the second cutter 2024. The first cutter 2023 is located in the second quadrant and the fourth quadrant respectively, and the second cutter 2024 is located on the vertical diameter line respectively. The first cutter 2023 and the second cutter 2024 are evenly arranged to balance the load on the cutter 202 and reduce the vibration of the cutter 202 during construction.

[0081] The cutting edges of the first cutter 2023 and the second cutter 2024 are inclined inward and downward at an angle of 10°-20°. This prevents the cutter head from wobbling during the rotation of the cutter 202 and also allows for a smooth transition at the junction of the base plate body 2011 and the mounting groove 2012. Preferably, the angle is 15°, which can create a larger flat excavation area.

[0082] Furthermore, the outer ring cutting tool also includes a pair of third cutting tools 2025 and a fourth cutting tool 2026 located at the edge of the base plate 201. The third cutting tools 2025 are located in the first and third quadrants. In the radial direction of the base plate 201, the cutting edges of the third cutting tools 2025 and the fourth cutting tools 2026 are inclined outward and upward with an included angle of 30°-40°. The third cutting tools 2025 and the fourth cutting tools 2026 are both located relative to each other at the edge of the base plate body 2011 and are inclined outward, which facilitates the cutting tool 202 to contact the well wall, further enhancing the guiding effect of the drill bit and the effect of trimming the rock on the well wall. Preferably, the included angle is 35°.

[0083] There are three pairs of fourth cutting tools 2026, which are evenly spaced along the circumference of the base plate body 2011, so that the cutting tools 202 in each direction can contact the well wall.

[0084] Furthermore, the cutting tool 202 and the tool holder form a cutting disc. The center of gravity of the cutting disc is horizontally projected onto the center of the base plate 201. When the cutting disc rotates, it reaches a state of dynamic balance, resulting in less drill bit wobbling and less impact load, which can extend the service life of the cutting tool 202 and other components.

[0085] Specifically, with the center of the base plate 201 as the zero point of the coordinate system, the horizontal axis of the base plate 201 is the X-axis, and the vertical axis is the Y-axis. The sum of the products of the distances from the center of gravity of each tool and tool holder to the X and Y axes is zero, as shown in the following formula, where Gi is the weight of the tool and gi is the weight of the tool holder. .

[0086] like Figure 6 As shown, the drill bit includes a slag discharge channel 106 extending vertically and a high-pressure air chamber 107 outside the slag discharge channel 106. The slag discharge channel 106 and the high-pressure air chamber 107 in the guide device 10 are part of the aforementioned slag discharge channel and high-pressure air chamber. The high-pressure air chamber 107 is arranged adjacent to the slag discharge channel 106 to facilitate the mixing of high-pressure air entering from the high-pressure air chamber 107 with the mud to form a low-density fluid, which drives the mud containing rock cuttings from the bottom of the well to be discharged upward to the surface through the slag discharge channel 106, avoiding accumulation at the bottom of the well that could cause the drill bit to jam or reduce efficiency.

[0087] The cutterhead assembly 20 also includes a plurality of slurry return ports 206 provided on the base plate 201, and are spaced apart along the circumference of the base plate 201 at the edge of the base plate 201. The slurry return ports 206 return a small amount of slurry to the vicinity of the cutterhead to avoid the formation of a vacuum environment around the cutterhead.

[0088] The cutterhead assembly 20 also includes a ring plate 207 located outside the slurry return port 206, so that the cutterhead forms a complete cylindrical structure, preventing protruding rocks or falling debris from the well wall from getting stuck in the gap of the slurry return port 206, avoiding drill bit shaking or damage, thereby ensuring the stability of the drill bit during drilling.

[0089] The cutter head assembly 20 also includes a fixing device 203 fixedly connected to the side of the base plate 201 opposite to the cutter. The slag discharge channel 106 includes a slag discharge bend 1061 that slopes outward and passes through the fixing device 203. Due to the offset design of the slag discharge bend 1061 relative to the center of the base plate 201 and the asymmetry of the structure of the base plate 201, the cutter head assembly 20 also includes a counterweight cavity 204 spaced apart from the slag discharge bend 1061. The counterweight cavity 204 is a cylindrical structure. After the other structures of the cutter head are completely designed, the specific position and size of the counterweight cavity 204 are designed according to the position of the cutter head's center of gravity.

[0090] The cutter head assembly 20 also includes a stop block 205 located at the end of the slag discharge bend 1061 to prevent larger slag blocks from entering the slag discharge bend 1061.

[0091] The other positions of the fixing device 203 are counterweight rings to increase the weight of the drill bit. The preparation method and material of the counterweight rings are the same as those of the counterweight rings in the guide device 10, and will not be described in detail here.

[0092] As a preferred embodiment of this application, such as Figure 6 As shown, the guide module also includes a connecting device 30 fixedly installed on the side of the guide device 10 away from the cutter head assembly 20, a fixing member 40 for fixing the guide device 10 and the connecting device 30, and a number of connecting bolts. The connecting bolts include forward bolts and reverse bolts, which are symmetrically arranged. That is, the forward bolts are locked clockwise and the reverse bolts are locked counterclockwise, with opposite directions, to achieve a self-locking effect. During the operation of the drill bit, the bolts are less likely to fall off.

[0093] In this embodiment, the slag discharge channel 106 also includes a lower slag discharge pipe located in the guide device 10 adjacent to the fixed device 203. The lower slag discharge pipe has a plurality of mixing air holes 1062, which can quickly meet the requirements of the critical condition of the submersion ratio of the air-lift reverse circulation mud, and facilitate the mixing of high-pressure air and mud to form a low-density fluid.

[0094] like Figure 8 As shown, the fixing member 40 is interference-fitted with the flange of the guide device 10 and the connecting device 30. The fixing member 40 is an airfoil I-type clamp. The fixing member 40 includes a pair of airfoils 41, a web plate 42 fixedly connected to the airfoils 41, and mating bolt holes spaced apart and symmetrically arranged on the airfoils 41. The forward bolts and reverse bolts correspond to the mating bolt holes, that is, fixing the guide device 10 and the connecting device 30 together to ensure that there is no loosening during rotation, withstand dynamic torque, resist the dynamic torque generated by the rotation of the drill bit, and improve the stability of the drill bit.

[0095] The end of the transition module 50 is provided with an internal hexagonal toothed connector 51 for docking with the drill pipe. The slag discharge channel 106 extends to the upper end of the transition module 50. The transition module 50 is conical. Due to the large change in cross-sectional area of ​​the transition module 50, it is prone to cracks and fractures under alternating loads. Compared with the traditional method of casting the transition module with cast steel, this application uses 35CrMo material forging and machining to improve the strength of the transition module 50.

[0096] In summary, the guiding device for vertical shaft drilling rigs of this application has a compact and symmetrical overall structure, which improves the stability, service life and construction efficiency of the guiding device during operation.

[0097] It should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This way of describing the specification is only for clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

[0098] The detailed descriptions listed above are merely specific illustrations of feasible embodiments of this application and are not intended to limit the scope of protection of this application. All equivalent embodiments or modifications made without departing from the spirit of the art of this application should be included within the scope of protection of this application.

Claims

1. A guiding device for a vertical shaft drilling rig, characterized in that, include: The guide body includes at least two guide rollers mounted on the side of the guide body, mounting portions located at both ends of the guide body along the axial direction for mounting the upper and lower drilling tools, and a mounting seat located in the middle of the guide body for mounting the guide rollers; the guide rollers are arranged symmetrically about the guide body, and the distance between the guide rollers and the guide body is less than the radial dimension of the guide rollers.

2. The guiding device for a vertical shaft drilling rig as described in claim 1, characterized in that, The axial dimension of the guide roller is not greater than the distance between the guide roller and the mounting part.

3. The guiding device for a vertical shaft drilling rig as described in claim 1, characterized in that, In the radial direction of the guide body, the edge of the guide roller extends beyond the edge of the guide body.

4. The guiding device for a vertical shaft drilling rig as described in claim 1, characterized in that, The mounting base includes a fixing part fixed to the side of the guide body and a connecting part fixedly connected to the fixing part. The mounting base is T-shaped, and the connecting part is provided with mounting holes for mounting the guide roller so that the guide roller is spaced apart from the guide body.

5. The guiding device for a vertical shaft drilling rig as described in claim 1, characterized in that, The guiding device further includes a slag discharge channel that runs through the guiding body along the axial direction and a high-pressure air chamber located outside the slag discharge channel. The distance between the high-pressure air chamber and the slag discharge channel is not greater than the diameter of the high-pressure air chamber.

6. The guiding device for a vertical shaft drilling rig as described in claim 5, characterized in that, The guiding device also includes a receiving cavity located outside the high-pressure gas chamber, a counterweight ring disposed in the receiving cavity, and a cover plate for sealing the receiving cavity, wherein the radial dimension of the counterweight ring is larger than the diameter of the slag discharge channel.

7. The guiding device for a vertical shaft drilling rig as described in claim 6, characterized in that, The axial dimension of the mounting portion is greater than the thickness of the cover plate.

8. The guiding device for a vertical shaft drilling rig as described in any one of claims 1 to 7, characterized in that, The guide roller includes an installation structure, an outer cylinder structure sleeved on the outside of the installation structure, and at least one bearing structure for rotatably connecting the installation structure and the outer cylinder structure. The installation structure is provided with a connected lubrication cavity and a grease compensation cavity. The bearing structure is installed in the lubrication cavity. The guide roller also includes a pressure balancing structure disposed in the grease compensation cavity to apply pressure to the bottom wall of the compensation cavity away from the lubrication cavity, so that the internal pressure of the compensation cavity is not less than the external pressure.

9. The guiding device for a vertical shaft drilling rig as described in claim 8, characterized in that, The pressure balancing structure includes a piston that is in a sealing sliding fit with the compensation chamber, and an elastic element connected to the side of the piston away from the lubrication chamber, wherein the elastic element is in a compressed state.

10. A drill bit for use in a vertical shaft drilling rig, characterized in that, Includes the guiding device for a vertical shaft drilling rig as described in any one of claims 1 to 9.

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