A high-efficiency rock-breaking roller bit

Abstract

The application belongs to the technical field of roller bits, and particularly provides a high-efficiency rock breaking roller bit, which comprises a roller bit body, a centralizer and a breaking assembly, the lower end of the centralizer is detachably connected with the roller bit body, and the top of the centralizing unit is provided with the breaking assembly.When the bit is pulled up and stuck, the top of the centralizer will contact with the reduced diameter position, at which time the breaking assembly can be used to break the reduced diameter position. The diameter of the borehole at the reduced diameter position after being broken by the breaking assembly can be expanded to the same size or larger than the original borehole size, so that the centralizer and the roller bit body can smoothly pass through. The application detachably connects the centralizer with the roller bit body, and sets the breaking assembly on the centralizer, so that the roller bit body can be replaced after being worn out and scrapped, and the centralizer and the breaking assembly can continue to be used. Such a setting can not only make the roller bit have the anti-sticking function and ensure efficient construction, but also will not cause the production and use cost to greatly increase due to the setting of the breaking assembly.

Description

Technical Field

[0001] This invention belongs to the field of roller cone drill technology, specifically relating to a high-efficiency roller cone drill bit for rock breaking. Background Technology

[0002] Roller cone bits, PDC bits, and rotary drilling bits are all drilling tools used in geological drilling, formation sampling, oil and gas field drilling, pile foundation excavation, pipeline construction, and other fields. The most common type of roller cone bit is the tricone bit, which consists of a bit body, three cutting discs, and roller cones mounted on each cutting disc. There are chip removal flutes between adjacent cutting discs, and the bit body has flow channels communicating with these flutes. Nozzles are installed at the outlets of these flow channels. Drilling fluid enters the flow channels from the drill string and then exits from the three nozzles to clean up rock cuttings and other debris generated during drilling.

[0003] During drilling, encountering uneven geological formations can easily lead to stuck drill bits. For example, in fractured rock formations, chunks can easily break off from the borehole wall. In soft formations, the borehole diameter can easily shrink, resulting in a smaller borehole size. Stuck drill bits can cause the drill bit to become stuck during tripping in, making it difficult to retrieve the drill bit in a timely manner and affecting drilling efficiency.

[0004] Existing technologies offer several solutions to the "stuck drill" problem, such as installing cutting teeth at the rear end of the drill bit with their tips facing upwards. During drilling, if a block breaks or the drill bit's diameter decreases, the cutting teeth can break up the obstacle. However, this structure has the following drawbacks: the roller cone drill bit is a consumable part and needs to be replaced after a certain degree of wear. While the aforementioned measures in the existing technology, which place the cutting teeth at the rear end of the drill bit, can prevent stuck drills, the entire roller cone drill bit needs to be replaced when it wears down. Since stuck drills are a relatively rare event, if cutting teeth were installed on every roller cone drill bit produced to prevent occasional stuck drills, the production cost would increase significantly due to the expensive wear-resistant metal materials used for the cutting teeth. Furthermore, in practical applications, it is possible for a drill bit to wear down to the point of being unusable without ever experiencing a stuck drill incident. Summary of the Invention

[0005] Based on the above-mentioned technical problems, the present invention provides a high-efficiency roller cone drill bit for rock breaking, which aims to solve the problem that the production cost of a single drill bit is increased due to the measure of setting cutting teeth at the rear end of the roller cone drill bit to prevent the drill from getting stuck in the prior art.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is: to provide a high-efficiency rock-breaking roller cone drill bit, comprising: The body of the roller cone drill; A straightener includes a connecting post and a straightening unit. The lower end of the connecting post is detachably connected to the upper end of the roller cone drill body. The connecting post has an internal fluid inlet channel communicating with the internal flow channel of the roller cone drill body. The straightening unit is coaxially disposed on the outer periphery of the connecting post. A crushing component is disposed on top of the straightening unit, and the crushing diameter of the crushing component is greater than or equal to the drilling diameter of the roller cone drill body.

[0007] In one possible implementation, the top of the straightening unit is provided with an annular adjustment cavity around the connecting column, and the side wall of the liquid inlet channel is provided with an outlet hole and a liquid inlet hole respectively communicating with the adjustment cavity. The outlet hole is located above the inlet hole, and the inside of the liquid inlet channel is provided with a partition for separating the inlet hole and the outlet hole. The crushing assembly includes a hydraulic drive unit and multiple crushing units. The hydraulic drive unit is located on top of the centralizer. The lower part of the hydraulic drive unit slides in conjunction with the adjustment chamber and has a pressure chamber. The upper part of the hydraulic drive unit has a contact portion with the same diameter as the centralizer. The hydraulic drive unit has an upper dead point and a lower dead point. When it is at the upper dead point, the pressure chamber is vertically offset from the liquid outlet and the liquid inlet, respectively. When it is at the lower dead point, the pressure chamber communicates with the liquid outlet and is offset from the liquid inlet. Multiple crushing units are circumferentially spaced above the contact portion, and the hydraulic drive unit is used to drive the multiple crushing units to move along the radial direction of the contact portion.

[0008] In one possible implementation, the hydraulic drive unit includes: A mounting base is disposed on the top of the stabilizer. The lower part of the mounting base slides with the adjusting cavity and together with the connecting column forms the pressure chamber. The upper part of the mounting base extends outside the adjusting cavity and together with the connecting column forms a sliding cavity. The mounting base has a flow hole connecting the adjusting cavity and the sliding cavity. The side wall of the sliding cavity has multiple mounting grooves extending through its own wall thickness along the circumferential direction. Multiple crushing units are correspondingly disposed in the mounting grooves. The mounting base has the contact portion. A piston, slidably fitted within the sliding cavity, wherein the upper part of the piston is a conical surface and contacts and engages with one side of the crushing unit extending into the sliding cavity; and A first elastic element is disposed between the mounting base and the straightening unit, and is configured with a supporting force to keep the mounting base in the upper stop position.

[0009] In one possible implementation, the crushing unit includes: The breaking tooth has a movable part that slides into the mounting groove, and a breaking part facing the borehole wall, the movable part contacting the conical surface; and The second elastic element is disposed between the moving part and the mounting base, and is configured with a preload force that causes the breaking teeth to move toward the central axis of the mounting base.

[0010] In one possible implementation, the sidewall of the sliding cavity is provided with a plurality of pressure relief holes spaced apart along its circumference. The pressure relief holes penetrate the wall thickness itself and are located between two adjacent crushing teeth. The pressure relief holes are lower than the highest position that the piston can move.

[0011] In one possible implementation, the breaking tooth is either a roller or a PDC cutting tooth.

[0012] In one possible implementation, the first elastic element is an elastic telescopic rod, one end of which is connected to the mounting base and the other end is connected to the straightening unit.

[0013] In one possible implementation, the inlet hole, the outlet hole, and the flow hole are all provided in multiple circumferentially spaced along the connecting column.

[0014] In one possible implementation, the outer peripheral surface of the straightening unit is provided with a spiral chip removal channel, which runs through the straightening unit vertically, and the lower end of the chip removal channel is connected to the chip removal groove of the roller cone drill body in a one-to-one correspondence.

[0015] In one possible implementation, the surface between two adjacent chip removal channels is defined as a diameter-protecting section, and the outer surface of the diameter-protecting section is provided with diameter-protecting teeth.

[0016] Compared with existing technologies, the advantages of the high-efficiency rock-breaking roller cone drill bit provided in this application are: This application provides a high-efficiency rock-breaking roller cone drill bit, comprising a roller cone drill body, a stabilizer, and a crushing component. The lower end of the stabilizer is detachably connected to the roller cone drill body via a connecting post. The crushing component is mounted on the top of the stabilizer unit, and the stabilizer can drive the crushing component to move or rotate together. When the drill bit is pulled up and jamming occurs, the top of the stabilizer will contact the reduced-diameter area. At this time, the crushing component can crush the reduced-diameter area. Since the crushing diameter of the crushing component is greater than or equal to the borehole diameter, the borehole diameter at the reduced-diameter area can be enlarged to the same or larger than the original borehole size after crushing by the crushing component, allowing the stabilizer and roller cone drill body to pass smoothly, avoiding construction delays caused by jamming, and helping to improve construction efficiency. This application detachably connects the stabilizer and roller cone drill body and mounts the crushing component on the stabilizer. The roller cone drill body can be replaced after wear and tear. Since the lifespan of the stabilizer is longer than that of the roller cone drill body, the crushing component can be effective for a longer period of time. This design not only enables the roller cone drill bit to have the function of preventing jamming and ensuring efficient construction, but also avoids a significant increase in production and usage costs due to the inclusion of breakable components, achieving two goals at once. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a three-dimensional schematic diagram of a high-efficiency rock-breaking roller cone drill bit provided in an embodiment of the present invention; Figure 2 A cross-sectional view of the crushing component of a high-efficiency rock-breaking roller cone drill bit in a retracted state, as provided in an embodiment of the present invention. Figure 1 ; Figure 3 for Figure 2 Enlarged view of part A in the middle; Figure 4 A cross-sectional view of the breaking component of a high-efficiency rock-breaking roller cone drill bit in an expanded state, provided in an embodiment of the present invention; Figure 5 for Figure 4 Enlarged view of part B in the middle; Figure 6 A cross-sectional view of the crushing component of a high-efficiency rock-breaking roller cone drill bit in a retracted state, as provided in an embodiment of the present invention. Figure 2 ; Figure 7 for Figure 6 Enlarged view of a section in the middle C; Explanation of reference numerals in the attached figures: 10. Drill body; 11. Chip removal groove; 20. Centralizer; 21. Connecting column; 211. Liquid outlet; 212. Liquid inlet; 213. Separator; 214. Liquid inlet channel; 22. Centralizer unit; 221. Chip removal channel; 222. Diameter protection part; 223. Diameter protection tooth; 23. Limiting ring; 30. Crushing assembly; 31. Hydraulic drive unit; 311. Mounting base; 3111. Pressure chamber; 3112. Sliding chamber; 3113. Flow hole; 3114. Contact part; 3115. Pressure relief hole; 312. Piston; 3121. Conical surface; 313. First elastic element; 32. Crushing unit; 321. Crushing tooth; 3211. Moving part; 3212. Crushing part; 322. Second elastic element. Detailed Implementation

[0019] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0020] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0021] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0022] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" or "several" means two or more, unless otherwise explicitly specified.

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains.

[0024] Please refer to the following: Figures 1 to 7The following describes a high-efficiency rock-breaking roller cone drill bit provided in the embodiments of this application.

[0025] Please see Figure 1 and Figure 2 This application provides a high-efficiency rock-breaking roller cone drill bit, including a roller cone drill body 10, a stabilizer 20, and a breaking assembly 30. The roller cone drill body 10 is a tri-cone or other type of roller cone drill bit in the prior art, with a chip removal groove 11 formed between two adjacent cones. The interior of the roller cone drill body 10 has a flow channel for drilling fluid. The stabilizer 20 includes a connecting post 21 and a stabilizing unit 22. The lower end of the connecting post 21 is detachably connected to the upper end of the roller cone drill body 10. The interior of the connecting post 21 forms a fluid inlet channel 214 that communicates with the internal flow channel of the roller cone drill body 10. The stabilizing unit 22 is coaxially disposed on the outer periphery of the connecting post 21. The breaking assembly 30 is disposed on the top of the stabilizer 20. The breaking assembly 30 has a contracted state and an expanded state. When in the expanded state, the breaking diameter of the breaking assembly 30 is greater than or equal to the borehole diameter of the roller cone drill body 10.

[0026] Compared with the prior art, the beneficial effects of the high-efficiency rock-breaking roller cone drill bit provided in this application embodiment are: This application provides a high-efficiency rock-breaking roller cone drill bit, comprising a roller cone drill body 10, a stabilizer 20, and a crushing component 30. The lower end of the stabilizer 20 is detachably connected to the roller cone drill body 10 via a connecting post 21. The top of the stabilizer unit 22 is provided with the crushing component 30, and the stabilizer 20 can drive the crushing component 30 to move or rotate together. When the drill bit is pulled up and jamming occurs, the top of the stabilizer 20 will contact the reduced diameter position. At this time, the reduced diameter position can be crushed by the crushing component 30. Since the crushing diameter of the crushing component 30 is greater than or equal to the borehole diameter, the borehole diameter at the reduced diameter position can be expanded to the same or larger than the original borehole size after crushing by the crushing component 30, allowing the stabilizer 20 and the roller cone drill body 10 to pass smoothly, avoiding construction delays caused by jamming, and helping to improve construction efficiency.

[0027] In this embodiment, the centralizer 20 and the roller cone drill body 10 are detachably connected, and the crushing component 30 is mounted on the centralizer 20. The roller cone drill body 10 can be replaced after wear and tear, while the centralizer 20 and the crushing component 30 can continue to be used. Since the centralizer 20 has a longer lifespan than the roller cone drill body 10, the crushing component 30 can function for a longer period. This design not only provides the roller cone drill bit with anti-jamming functionality, ensuring efficient construction, but also avoids a significant increase in production and operating costs due to the inclusion of the crushing component 30, achieving two goals at once.

[0028] The roller cone drill body 10 can be directly selected from existing roller cone drill bits on the market, such as tricone drill bits. The roller cone drill body 10 is detachably connected to the lower end of the connecting post 21, which can be done by means of threaded connection, etc. It can be replaced after it wears down to a certain extent.

[0029] The stabilizer 20 is used to conform to the inner wall of the borehole during the downward drilling of the roller cone drill body 10, providing alignment and guidance, which helps to improve the stability of the drilling process and the verticality of the borehole. The stabilizer 20 includes a connecting post 21 and a stabilizer unit 22, which can be fixedly connected as a whole by welding or other methods. The lower end of the connecting post 21 is used for detachable connection with the roller cone drill body 10, and the upper end of the connecting post 21 is used for connection with the drill rod.

[0030] The centering unit 22 is disposed on the outer peripheral wall of the connecting column 21. The diameter of the centering unit 22 is adapted to the borehole diameter, and it can fit and guide the borehole inner wall during drilling. The axial length of the centering unit 22 should not be less than the length of the roller cone drill body 10, which helps to prevent borehole axis deviation and ensures that the verticality of the borehole is within a reasonable range.

[0031] The crushing component 30 is positioned on top of the straightening unit 22, such as... Figure 2 and Figure 4 The crushing component 30 has a contracted state and an expanded state. During normal drilling or lifting, the crushing component 30 is in the contracted state, the crushing unit 32 is not working, and the overall diameter of the crushing component 30 is smaller than the borehole diameter.

[0032] like Figure 1 and Figure 2 When in the contracted state, the edge of the crushing assembly 30 is within the range of the contact portion 3114. When the diameter of the weak geological layer decreases, the upward movement of the centralizer 20 is hindered, and the contact portion 3114 is used to contact the inner wall of the borehole after the diameter decreases. After moving to the diameter decrease position, the crushing assembly 30 switches from the contracted state to the expanded state, and the crushing assembly 30 is rotated by the drill rod and the connecting column 21 to expand the hole at the diameter decrease position.

[0033] The crushing component 30 can contract or expand radially. Optionally, a hydraulic rod can be installed on the top of the straightening unit 22 to push the crushing component 30 to move radially, thus contracting or expanding. Alternatively, a battery can be installed inside the straightening unit 22 to drive the crushing component 30 to expand or contract radially using an electric telescopic rod or a motor.

[0034] Please see Figures 2 to 7To facilitate the installation of the crushing assembly 30, the top of the straightening unit 22 is provided with an annular adjustment chamber surrounding the connecting column 21. The side wall of the fluid inlet channel 214 has an outlet hole 211 and an inlet hole 212, both communicating with the adjustment chamber. The outlet hole 211 is located above the inlet hole 212. The inside of the fluid inlet channel 214 is provided with a partition 213 to separate the inlet hole 212 and the outlet hole 211. During normal drilling, drilling fluid enters the fluid inlet channel 214 through the drill pipe and flows along... Figure 3 The flow path is indicated by the arrow. The specific flow path is: inlet channel 214, outlet hole 211, regulating chamber, inlet hole 212, inlet channel 214, internal flow channel of roller cone drill body 10, and drilling fluid nozzle.

[0035] The crushing assembly 30 includes a hydraulic drive unit 31 and multiple crushing units 32. The hydraulic drive unit 31 is located on top of the centralizer 20. The lower part of the hydraulic drive unit 31 slides in conjunction with the adjustment chamber and has a pressure chamber 3111. The upper part of the hydraulic drive unit 31 has a contact portion 3114 with the same diameter as the centralizer 20. The hydraulic drive unit 31 has an upper dead point and a lower dead point. When it is at the upper dead point, the pressure chamber 3111 is vertically offset from the outlet hole 211 and the inlet hole 212, respectively. When it is at the lower dead point, the pressure chamber 3111 is connected to the outlet hole 211 and is offset from the inlet hole 212. Multiple crushing units 32 are circumferentially spaced above the contact portion 3114. The hydraulic drive unit 31 is used to drive the multiple crushing units 32 to move along the radial direction of the contact portion 3114.

[0036] The hydraulic drive unit 31 can move up and down, such as Figure 3 As shown, during normal downward drilling or upward retrieval of the drill string, the hydraulic drive unit 31 is at the top dead center position. The pressure chamber 3111 of the hydraulic drive unit 31 is not connected to the outlet hole 211, and no drilling fluid enters, so the hydraulic drive unit 31 does not work.

[0037] When the hole is moved to the reduced diameter position, the upward movement of the straightening unit 22 is obstructed, and the protruding hole wall pushes the hydraulic drive unit 31 downward, causing the hydraulic drive unit 31 to move from the top dead center to the position shown in the image. Figure 4 and Figure 5 The lower dead center position is shown. The pressure chamber 3111 is connected to the outlet port 211. High-pressure drilling fluid enters the pressure chamber 3111 through the outlet port 211. The hydraulic drive unit 31 drives the crushing unit 32 to expand outward under the push of the high-pressure drilling fluid. The rotation of the drill pipe and connecting column 21 drives the crushing unit 32 to crush and enlarge the borehole at the narrowing position on the inner wall of the borehole.

[0038] After the hole is enlarged, the obstruction of the hole wall to the hydraulic drive unit 31 disappears, and the hydraulic drive unit 31 can be pushed back to the upper dead point by an external drive component (such as a hydraulic push rod, electric push rod, etc.).

[0039] Alternatively, please see Figure 3 and Figure 7 The hydraulic drive unit 31 includes a mounting base 311, a piston 312, and a first elastic element 313. The mounting base 311 is located on the top of the centralizer 20. The lower part of the mounting base 311 slides with the adjustment chamber and together with the connecting column 21 forms a pressure chamber 3111. The upper part of the mounting base 311 extends to the outside of the adjustment chamber and together with the connecting column 21 forms a sliding chamber 3112. The mounting base 311 has a flow hole 3113 that connects the adjustment chamber and the sliding chamber 3112. The side wall of the sliding chamber 3112 is provided with multiple mounting grooves that penetrate its own wall thickness along the circumferential direction. Multiple crushing units 32 are correspondingly arranged in the mounting grooves. The piston 312 is annular and slides within the sliding cavity 3112. The upper part of the piston 312 is a conical surface 3121, which contacts and engages with one side of the crushing unit 32 extending into the sliding cavity 3112. A first elastic element 313 is located between the mounting base 311 and the straightening unit 22, and is configured to provide support for holding the mounting base 311 at its top dead center position. Specifically, the first elastic element 313 can be a spring or a spring-loaded elastic telescopic rod. Both the mounting base 311 and the piston 312 can move up and down, but cannot rotate.

[0040] like Figure 7 As shown, one end of the elastic telescopic rod is connected to the mounting base 311, and the other end is connected to the straightening unit 22. To ensure uniform force distribution and more stable support, multiple elastic telescopic rods can be spaced out along the circumference.

[0041] To improve sealing, a sealing ring or sealing ring can be provided between the inner wall of the piston 312 and the sliding cavity 3112, and between the lower part of the mounting base 311 and the adjusting cavity. Both the sealing ring and the sealing ring are common sealing elements and can be directly selected from existing products on the market.

[0042] Mounting base 311 also has a contact portion 3114 for contacting the reduced borehole diameter position. The shape and size of the contact portion 3114 correspond to the top of the centering unit 22, thereby forming a relief groove in the contact portion 3114 corresponding to the top outlet of the cuttings removal channel 221 to facilitate the discharge of cuttings and drilling fluid. The connecting column 21 has a limiting ring 23, which is located at the upper stop position of the mounting base 311 to limit the mounting base 311 and prevent the mounting base 311 from moving upward.

[0043] During the lifting process, the contact part 3114 contacts the protruding borehole wall. The contact part 3114 overcomes the elastic force of the first elastic element 313, driving the entire mounting base 311 downward to the lower dead center. High-pressure drilling fluid enters the pressure chamber 3111 and flows through the flow hole 3113 into the sliding chamber 3112, driving the piston 312 upward. The conical surface 3121 of the piston 312 can push multiple breaking units 32 outward to expand until they abut against the inner wall of the borehole. The drill pipe and the centralizer 20 drive the breaking units 32 to rotate, expanding the borehole at the reduced diameter position. After the borehole is expanded, under the support force of the first elastic element 313, the hydraulic drive unit 31 returns to the upper dead center, and the pressure chamber 3111 and the fluid outlet 211 are vertically offset and no longer connected.

[0044] Please see Figure 3 , Figure 5 and Figure 5 The crushing unit 32 includes crushing teeth 321 and a second elastic member 322. The crushing teeth 321 can be functionally divided into a moving part 3211 that slides into the mounting groove, and a crushing part 3212 facing the borehole wall. The moving part 3211 has an inclined surface that contacts and engages with a conical surface 3121. When the piston 312 moves upward, it can push the moving part 3211 outward through the conical surface 3121, causing the crushing part 3212 to abut against the borehole wall. The crushing part 3212 is used to crush the rock on the inner wall of the borehole. The second elastic member 322 is disposed between the moving part 3211 and the mounting base 311 and is configured with a preload force that moves the crushing teeth 321 towards the central axis of the mounting base 311.

[0045] The rock-breaking tooth 321 can be a common structure used for rock breaking, such as roller cones and PDC cutting teeth. Its material is the same as that of existing roller cones or PDC cutting teeth, with high hardness and high wear resistance, enabling it to break rocks.

[0046] The second elastic element 322 can be a spring or other component that can achieve elastic extension and contraction. When the mounting base 311 is reset from the lower dead point to the upper dead point, since the pressure chamber 3111 is no longer connected to the liquid outlet 211, the piston 312 will fall under the action of gravity after the hydraulic pressure disappears, and the breaking tooth 321 will be reset to the contracted state under the pre-tightening force of the second elastic element 322.

[0047] Please see Figure 1 and Figure 2 The sidewall of the sliding cavity 3112 is provided with multiple pressure relief holes 3115 spaced apart along its circumference. The pressure relief holes 3115 penetrate the wall thickness itself and are located between two adjacent crushing teeth 321. The position of the pressure relief holes 3115 should be lower than the highest position that the piston 312 can move. Specifically, it can be set at the lowest position of the sidewall of the sliding cavity 3112 to prevent the pressure relief holes 3115 from being blocked by the piston 312 and unable to relieve pressure smoothly.

[0048] Since drilling fluid enters the sliding cavity 3112 through the flow hole 3113 and then exits through the pressure relief hole 3115, the diameter of the pressure relief hole 3115 should not be too large in order to ensure that there is sufficient pressure inside the sliding cavity 3112 to lift the piston 312. Specifically, the sum of the cross-sectional areas of multiple pressure relief holes 3115 should be less than or equal to the sum of the cross-sectional areas of multiple flow holes 3113.

[0049] The pressure relief hole 3115 is designed to allow the drilling fluid remaining inside the sliding cavity 3112 to be discharged after the hole is enlarged. On the other hand, since the pressure relief hole 3115 is located between the two breaking teeth 321, when the breaking unit 32 enlarges the hole wall, the drilling fluid will be ejected from the pressure relief hole 3115, carrying away the rock cuttings generated by the breaking, thus playing the role of cuttings removal.

[0050] Please see Figure 2 Since the regulating chamber, pressure chamber 3111 and sliding chamber 3112 are all annular, the corresponding inlet hole 212, outlet hole 211 and flow hole 3113 can be provided in multiple intervals along the circumference of the connecting column 21, so that the drilling fluid flows more evenly and quickly.

[0051] Please see Figure 1 The outer circumferential surface of the straightening unit 22 is provided with a spiral chip removal channel 221, which runs vertically through the straightening unit 22. The lower end of the chip removal channel 221 is connected vertically to the chip removal groove 11 of the roller cone drill body 10, ensuring smooth chip removal. When a three-roller drill body is used, three chip removal channels 221 are provided.

[0052] Please see Figure 1 The surface between two adjacent chip removal channels 221 is defined as the diameter protection section 222. The outer surface of the diameter protection section 222 is provided with multiple diameter protection teeth 223, which are evenly distributed on the outer surface of the diameter protection section 222. The diameter protection teeth 223 can continuously cut and clean the hole wall when the straightening unit 22 rotates, ensuring the consistency of the drilled hole size and specifications.

[0053] There are no specific restrictions on the shape, structure and arrangement of the caliper 223; users can set it themselves as needed.

[0054] It is understood that the parts in the above embodiments can be freely combined or deleted to form different combined embodiments. The specific contents of each combined embodiment will not be repeated here. After this description, it can be considered that the present invention specification has recorded each combined embodiment and can support different combined embodiments.

[0055] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-efficiency rock-breaking roller cone drill bit, characterized in that, include: Drill body (10); A straightener (20) includes a connecting post (21) and a straightening unit (22). The lower end of the connecting post (21) is detachably connected to the upper end of the roller cone drill body (10). The connecting post (21) has an internal fluid inlet channel (214) communicating with the internal flow channel of the roller cone drill body (10). The straightening unit (22) is coaxially disposed on the outer periphery of the connecting post (21). A crushing component (30) is disposed on the top of the straightening unit (22), and the crushing diameter of the crushing component (30) is greater than or equal to the drilling diameter of the roller cone drill body (10). The top of the straightening unit (22) is provided with an annular adjustment cavity around the connecting column (21). The side wall of the liquid inlet channel (214) is provided with an outlet hole (211) and an inlet hole (212) respectively communicating with the adjustment cavity. The outlet hole (211) is located above the inlet hole (212). The inside of the liquid inlet channel (214) is provided with a partition (213) for separating the inlet hole (212) and the outlet hole (211). The crushing assembly (30) includes a hydraulic drive unit (31) and multiple crushing units (32). The hydraulic drive unit (31) is located on top of the straightening unit (22). The lower part of the hydraulic drive unit (31) slides with the adjustment chamber and has a pressure chamber (3111). The upper part of the hydraulic drive unit (31) has a contact part (3114) with the same diameter as the straightening unit (22). The hydraulic drive unit (31) has an upper dead point and a lower dead point. When it is at the upper dead point, the pressure chamber (3111) is vertically offset from the liquid outlet (211) and the liquid inlet (212). When it is at the lower dead point, the pressure chamber (3111) communicates with the liquid outlet (211) and is offset from the liquid inlet (212). Multiple crushing units (32) are circumferentially spaced above the contact portion (3114), and the hydraulic drive unit (31) is used to drive the multiple crushing units (32) to move along the radial direction of the contact portion (3114); The hydraulic drive unit (31) includes: Mounting base (311) is located on top of the stabilizer (20). The lower part of the mounting base (311) slides with the adjustment cavity and together with the connecting column (21) forms the pressure chamber (3111). The upper part of the mounting base (311) extends to the outside of the adjustment cavity and together with the connecting column (21) forms a sliding cavity (3112). The mounting base (311) has a flow hole (3113) connecting the adjustment cavity and the sliding cavity (3112). The side wall of the sliding cavity (3112) is provided with multiple mounting grooves that penetrate its own wall thickness along the circumferential direction. Multiple crushing units (32) are correspondingly arranged in the mounting grooves. The mounting base (311) has the contact part (3114). A piston (312) is slidably fitted within the sliding cavity (3112). The upper part of the piston (312) is a conical surface (3121) and contacts the side of the crushing unit (32) extending into the sliding cavity (3112). A first elastic element (313) is disposed between the mounting base (311) and the straightening unit (22) and is configured with a supporting force to keep the mounting base (311) in the upper stop position.

2. The high-efficiency rock-breaking roller cone drill bit according to claim 1, characterized in that, The crushing unit (32) includes: The breaking tooth (321) has a movable part (3211) that slides with the mounting groove, and a breaking part (3212) facing the borehole wall, the movable part (3211) contacting the conical surface (3121); and The second elastic element (322) is disposed between the moving part (3211) and the mounting base (311) and is configured with a preload force that causes the breaking tooth (321) to move toward the central axis of the mounting base (311).

3. The high-efficiency rock-breaking roller cone drill bit according to claim 2, characterized in that, The sidewall of the sliding cavity (3112) is provided with a plurality of pressure relief holes (3115) spaced apart along its circumference. The pressure relief holes (3115) penetrate the wall thickness and are located between two adjacent crushing teeth (321). The pressure relief holes (3115) are lower than the highest position that the piston (312) can move.

4. The high-efficiency rock-breaking roller cone drill bit according to claim 2, characterized in that, The breaking tooth (321) is one of a roller cone and a PDC cutting tooth.

5. A high-efficiency rock-breaking roller cone drill bit according to claim 1, characterized in that, The first elastic element (313) is an elastic telescopic rod, one end of which is connected to the mounting base (311) and the other end is connected to the straightening unit (22).

6. The high-efficiency rock-breaking roller cone drill bit according to claim 1, characterized in that, The inlet hole (212), the outlet hole (211) and the flow hole (3113) are all provided in multiple spaces along the circumference of the connecting column (21).

7. The high-efficiency rock-breaking roller cone drill bit according to claim 1, characterized in that, The outer circumferential surface of the straightening unit (22) is provided with a spiral chip removal channel (221), which runs through the straightening unit (22) from top to bottom. The lower end of the chip removal channel (221) is connected to the chip removal groove (11) of the roller cone drill body (10) in a one-to-one correspondence.

8. A high-efficiency rock-breaking roller cone drill bit according to claim 7, characterized in that, The surface between two adjacent chip removal channels (221) is defined as the diameter protection part (222), and the outer surface of the diameter protection part (222) is provided with diameter protection teeth (223).

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