Integrated pulse percussion drilling bit

Abstract

The invention discloses an integrated pulse percussion drilling bit, which relates to the technical field of drills and comprises a bit body and a pulse generating mechanism, and cutting teeth for cutting and breaking rocks are distributed on the crown of the bit body; the pulse generating mechanism is arranged in the drill bit body and used for converting energy of drilling fluid flowing through the pulse generating mechanism into periodic pressure pulses. Wherein the periodic pressure pulses enable the drill bit body and the cutting teeth on the drill bit body to generate axial impact, and therefore impact rock breaking and cutting rock breaking are synchronously carried out. The length of the tool can be shortened, the energy utilization efficiency is improved, and the rock breaking self-adaptive capacity is enhanced.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of drill bits, in particular to an integrated pulsating impact drilling bit. BACKGROUND

[0002] In the oil and gas drilling engineering, improving the rate of penetration and reducing the drilling cost is an eternal pursuit. The drill bit, as the core tool for directly breaking rock, directly affects the drilling efficiency. At present, the two types of rock breaking tools mainly used in the field are PDC drill bits and impact speed increasing tools, and the two have obvious limitations in principle and applicability: the PDC drill bit uses polycrystalline diamond compact as a cutting tooth, and breaks rock through rotary shearing, which has the advantages of high rate of penetration and long service life in medium-soft to medium-hard homogeneous formations. However, its rock breaking method relies on continuous cutting, and in hard, abrasive or soft and hard alternating formations, the cutting tooth is prone to rapid wear, tooth collapse and rapid drilling speed decline, and lacks impact auxiliary rock breaking capability. The impact speed increasing tool (including hydraulic and mechanical impactors) breaks rock by generating high-frequency impact load, which can effectively deal with hard rock formations and relieve bit stick-slip vibration. However, such tools usually do not have self-cutting capability and need to be used in combination with PDC drill bits or roller bits to form a split series structure of "impact tool + drill bit". This combination has the following inherent defects: Tool string length increases: the introduction of an additional tool section reduces the passability and operational flexibility in complex structure wellbores such as directional wells and horizontal wells; Low energy transfer efficiency: impact load needs to be transmitted to the drill bit through multiple mechanical interfaces (such as threaded connections), resulting in energy loss and lag; Complex structure, reduced reliability: increases the risk of failure of connection seals, thread locking, etc. Poor functional synergy: impact and cutting actions are separated in time and space, and the dynamic fusion and adaptive adjustment of the rock breaking process are not achieved.

[0003] Therefore, there is an urgent need for an integrated tool that can deeply integrate pulsating impact function and PDC cutting function in the same drill bit body, in order to shorten the tool length, improve energy utilization efficiency, and enhance the rock breaking adaptive ability, thereby improving the drilling economy and operational safety. SUMMARY

[0004] The purpose of the present application is to provide an integrated pulsating impact drilling bit to solve the problems existing in the prior art and shorten the tool length, improve the energy utilization efficiency, and enhance the rock breaking adaptive ability.

[0005] To achieve the above purpose, the present application provides the following solutions: The application provides a one-piece pulsating impact drilling bit, which comprises a bit body and a pulse generating mechanism, and a cutting tooth for cutting and breaking rocks is arranged on the crown of the bit body; the pulse generating mechanism is arranged in the bit body and is used for converting the energy of drilling fluid flowing therethrough into periodic pressure pulses; wherein the periodic pressure pulses cause the bit body and the cutting tooth thereon to produce axial impact, so that synchronous impact and cutting and breaking rocks are realized.

[0006] Preferably, the pulse generating mechanism comprises an upper valve body and a lower valve body arranged in opposite rotation, and fluid channels are arranged on the upper valve body and the lower valve body respectively; the upper valve body is driven to rotate by the drilling fluid flowing therethrough, so that the fluid channels on the two valve bodies are periodically overlapped and staggered, thereby generating the pressure pulses.

[0007] Preferably, the fluid channels of the upper valve body and the lower valve body are eccentrically arranged in arc-shaped holes of the upper valve body and the lower valve body.

[0008] Preferably, the structure for driving the upper valve body to rotate by the drilling fluid comprises a fixed flow guiding unit and a rotating impeller unit; the fixed flow guiding unit is fixedly arranged in the bit body and is used for guiding and accelerating the flowing drilling fluid; the rotating impeller unit is coaxially fixedly connected with the upper valve body and is located downstream of the fixed flow guiding unit and is rotated by the drilling fluid guided by the fixed flow guiding unit, thereby driving the upper valve body.

[0009] Preferably, the rotating impeller unit is coaxially fixedly connected with the upper valve body through a torque transmission key.

[0010] Preferably, the bit body comprises a connectable upper joint and a lower bit, and the pulse generating mechanism is arranged in a cavity formed by the connection of the upper joint and the lower bit.

[0011] Preferably, the fixed flow guiding unit is fixed to the lower bit through at least one positioning pin.

[0012] Preferably, coaxial blind holes are arranged on the opposite end faces of the upper valve body and the lower valve body, diamond support columns are arranged in the blind holes, the two diamond support columns protrude from the blind holes, and the end faces of the two diamond support columns have a gap between the upper valve body and the lower valve body.

[0013] Preferably, the upper joint and the lower bit are connected through a toothed structure to transmit torque.

[0014] Preferably, the cutting tooth is a PDC composite sheet, and the cutting tooth comprises a non-planar cutting tooth.

[0015] The application has the following technical effects relative to the prior art: This embodiment achieves a high degree of structural integration by embedding the pulse generator. Compared to split tools, it eliminates intermediate connecting components, significantly shortening the length of the downhole tool string. This structural integration brings multiple advantages: First, the energy transmission path is greatly shortened and made more direct. Pulse energy does not need to be transmitted through additional threaded joints or other mechanical interfaces, reducing energy scattering, hysteresis, and loss during transmission. This allows more fluid energy to be efficiently converted into effective rock-breaking work, improving energy utilization efficiency. Second, the reliability of the tool is enhanced because the weakest connection link, the "impact tool-drill bit," which is most prone to leakage and disengagement, is eliminated, reducing the risk of downhole accidents. Finally, the integrated design optimizes the synchronization of impact and cutting. The pulse excitation acts directly on the bearing body of the cutting teeth, resulting in a faster and more direct response, laying the physical foundation for subsequent lithology-adaptive rock breaking. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of an integrated pulsed impact drilling bit provided in an embodiment of the present invention; Figure 2 A cross-sectional view of an integrated pulsed impact drilling bit provided in an embodiment of the present invention; Figure 3 This is a schematic diagram of the rotating impeller unit. Figure 4 A schematic diagram of the structure of the fixed flow guide unit and the rotating impeller unit; Figure 5 This is a schematic diagram of the upper valve body; In the diagram: 1-Upper connector; 2-Fixed flow guide unit; 3-Positioning pin; 4-Transmission key; 5-Rotating impeller unit; 6-Anti-drop block; 7-Upper valve body; 8-Diamond support column; 9-Lower valve body; 10-Lower drill bit; 11-Fluid channel. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] The purpose of this invention is to provide an integrated pulsed impact drilling bit to solve the problems existing in the prior art, shorten tool length, improve energy utilization efficiency, and enhance rock breaking adaptive capability.

[0020] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0021] The following is combined Figures 1 to 5 The following describes embodiments of the present invention.

[0022] This invention provides an integrated pulsating impact drilling bit, comprising: a bit body and a pulse generating mechanism. The bit body crown is provided with cutting teeth for cutting and breaking rock. The pulse generating mechanism is built into the bit body and is used to convert the energy of the flowing drilling fluid into periodic pressure pulses. The periodic pressure pulses cause the bit body and its cutting teeth to generate axial impact, thereby realizing the synchronous operation of impact rock breaking and cutting rock breaking.

[0023] This embodiment achieves a high degree of structural integration by embedding the pulse generator. Compared to split tools, it eliminates intermediate connecting components, significantly shortening the length of the downhole tool string. This structural integration brings multiple advantages: First, the energy transmission path is greatly shortened and made more direct. Pulse energy does not need to be transmitted through additional threaded joints or other mechanical interfaces, reducing energy scattering, hysteresis, and loss during transmission. This allows more fluid energy to be efficiently converted into effective rock-breaking work, improving energy utilization efficiency. Second, the reliability of the tool is enhanced because the weakest connection link, the "impact tool-drill bit," which is most prone to leakage and disengagement, is eliminated, reducing the risk of downhole accidents. Finally, the integrated design optimizes the synchronization of impact and cutting. The pulse excitation acts directly on the bearing body of the cutting teeth, resulting in a faster and more direct response, laying the physical foundation for subsequent lithology-adaptive rock breaking.

[0024] One further purpose of shortening the tool length is to improve the ability to create an inclined plane.

[0025] In some embodiments, the pulse generating mechanism includes an upper valve body 7 and a lower valve body 9 arranged in a relatively rotatable manner, with fluid channels 11 respectively provided on the upper valve body 7 and the lower valve body 9; the upper valve body 7 is driven to rotate by the drilling fluid flowing through it, so that the fluid channels 11 on the two valve discs periodically overlap and stagger, thereby generating pressure pulses.

[0026] The relative rotating disc valve structure of the embodiment generates pulses, and the technical effect is to realize linear correlation and controllability of pulse frequency and drilling fluid flow rate (or drill bit rotation speed). The pulse frequency is determined by the rotation speed of the upper valve body 7, and the rotation speed is directly controlled by the drilling fluid discharge or the design of the driving impeller. This allows the operator to directly control the downhole impact frequency within a certain range by adjusting the ground pump discharge, and to achieve preliminary "adaptation" to the rock breaking rhythm of different formations.

[0027] As an alternative to the embodiment, the relative rotating valve structure is not limited to disc shape, but can also be a cylindrical slide valve, that is, windows are opened on the upper and lower coaxial sleeves, and the opening and closing of the windows are realized by relative rotation. Alternatively, two disc valves with different rotation speeds can be used to realize the periodic opening and closing of the fluid passage 11 through the speed difference.

[0028] In some embodiments, the fluid passage 11 of the upper valve body 7 and the lower valve body 9 is eccentrically arranged in the arc-shaped hole of the upper valve body 7 and the lower valve body 9. Of course, the shape of the fluid passage 11 is not limited to fan-shaped, but can also be an elliptical, oblong or special curve shaped hole. As long as the design can realize the periodic nonlinear change of the flow area.

[0029] In some examples, the lower valve body 9 is fixed inside the drill bit body, specifically by threaded connection.

[0030] In some embodiments, the structure for driving the upper valve body 7 to rotate by the drilling fluid includes a fixed flow guiding unit 2 and a rotating impeller unit 5. The fixed flow guiding unit 2 is fixedly arranged in the drill bit body and is used to guide and accelerate the inflowing drilling fluid. The rotating impeller unit 5 is coaxially fixedly connected with the upper valve body 7 and is located downstream of the fixed flow guiding unit 2. The rotating impeller unit 5 is rotated by the drilling fluid discharged by the fixed flow guiding unit 2, thereby driving the upper valve body 7.

[0031] The embodiment uses a split fixed flow guiding and rotating impeller unit 5 to realize efficient conversion and directional transmission of the drilling fluid energy. The fixed flow guiding unit 2 converts the turbulent drilling fluid into a jet flow with concentrated direction and higher kinetic energy, significantly improving the driving efficiency. The rotating impeller unit 5 as an independent power module facilitates parameterized design of the blades according to the required torque and rotation speed. This design enables the driving performance (rotation speed, torque) of the pulse generating mechanism to be well matched with the working conditions (discharge, pump pressure) of the drilling pump, ensuring that the upper valve body 7 can obtain stable and reliable rotation power within a wide range of drilling parameters, thereby ensuring the stability of the pulse frequency.

[0032] In some examples, the driving mode can not use a split impeller, but a "turbine-disc-valve integrated" design, that is, the turbine blades are directly machined on the shaft or top of the upper valve body 7, so that the upper valve body 7 itself becomes a turbine rotor. Alternatively, the drilling fluid can be used to directly impact the asymmetrically distributed stress surface on the upper valve body 7 to generate a rotating torque, similar to the principle of a water turbine.

[0033] In some embodiments, the rotating impeller unit 5 is coaxially fixedly connected to the upper valve body 7 through a torque transmission key 4.

[0034] The embodiment uses a torque transmission key 4 connection, which directly provides a simple, reliable and high-capacity torque transmission scheme. The key connection can withstand large pulsating torques at high speeds, ensuring that the power of the rotating impeller unit 5 is transmitted to the upper valve body 7 without loss. This connection method has mature processing technology, easy assembly, and is easy to disassemble, maintain or replace (such as after the impeller wears out). Compared with interference fit, it avoids the complex process of hot assembly and cold shrinkage; compared with spline, it reduces the processing precision requirement and cost. In the limited installation space underground, the key connection achieves a good balance between strength and maintainability.

[0035] As an alternative to this embodiment, the torque transmission method is not limited to a flat key, but can also use spline connection, hexagonal shaft connection, or use the friction force generated by the high-strength threaded pair when tightened to transmit torque. For miniaturized design, a pin radial through method can also be considered for torque transmission.

[0036] In some embodiments, the drill bit body includes a connectable upper joint 1 and a lower drill bit 10, and the pulse generating mechanism is arranged in the cavity formed by the connection of the two.

[0037] This embodiment uses a split "joint + crown" configuration, which primarily facilitates the manufacture, assembly and maintenance of the drill bit. The pulse generating mechanism and its internal precision components (such as impellers, disc valves, bearings) can be accurately installed, adjusted and sealed in one half of the upper joint 1 or the lower drill bit 10 in a factory environment, and then the final assembly is performed. This modular design improves production efficiency and assembly quality. In addition, when the crown is worn or the pulse mechanism needs to be repaired, only the crown or joint part can be replaced or repaired, reducing the cost of use and maintenance. At the same time, this configuration is also conducive to the flexible combination of standardized pulse generating modules with drill bits of different crown designs for different strata.

[0038] As an alternative to this embodiment, the drill bit body can also be integrally forged or sintered, and all parts of the pulse generating mechanism are axially loaded from the rear end of the drill bit body, and then sealed and fixed by a rear end gland or threaded plug. This way is more integrated, but the manufacturing and maintenance are more difficult.

[0039] In some embodiments, the fixed flow guiding unit 2 is fixed to the lower drill bit 10 by at least one positioning pin 3.

[0040] In some embodiments, the fixed flow guiding unit 2 is also in the shape of an impeller, and the twist direction of the impeller blades is opposite to the twist direction of the blades of the rotating flow guiding unit 5.

[0041] The positioning pin 3 fixing mode is used in the present embodiment to achieve quick, accurate positioning and firm fixing of the fixed flow guiding unit 2. Of course, the fixed flow guiding unit 2 can also be fixed by interference fit press fitting between its outer cylindrical surface and the inner hole of the lower drill bit 10, or by designing external threads on the fixed flow guiding unit 2 and screwing into the corresponding internal threads of the lower drill bit 10, or by using a snap ring or a retaining ring for axial limiting.

[0042] In some embodiments, the lower valve body 9 is connected to the inside of the lower drill bit 10 by external threads, i.e., a section of internal threads is provided inside the lower drill bit 10.

[0043] In some embodiments, the opposite end faces of the upper valve body 7 and the lower valve body 9 are provided with coaxial blind holes, and diamond support columns 8 are provided in the blind holes. The two diamond support columns 8 protrude from the blind holes, and the end faces of the two diamond support columns 8 have a gap between the upper valve body 7 and the lower valve body 9.

[0044] The core beneficial effect brought by the coaxial and opposite diamond support column 8 structure is to achieve the balance between "precise gap maintenance with extremely low friction" and "efficient axial force transmission". The specific derivation is as follows: First, the diamond material has the lowest friction coefficient and the highest hardness and wear resistance. When the two end faces of the diamond support column 8 are used as a contact pair, the friction resistance and wear generated during the high-speed relative rotation of the upper and lower valve bodies 9 can be reduced to a very low level, which is directly beneficial to reduce the driving energy consumption, reduce the heat generation and significantly prolong the service life of the key moving parts. Second, compared with the scheme using large-area contact, the "column-column" point contact or small-area contact form greatly reduces the contact area, which not only further reduces the friction torque, but more importantly, it can effectively avoid the risk of "sticking" or "pulling" of the large-area end face of the two-disc valve due to fluid impurities or slight thermal deformation, improving the operation reliability of the mechanism in complex drilling fluid environment. Finally, the contact between the end faces of the two high-hardness support columns can accurately limit and maintain the working gap between the upper and lower valve bodies 9. This gap is crucial, as it ensures that the fluid passage 11 (such as the arc-shaped hole) of the disc valve can effectively throttle to generate pulses when it is staggered, and can fully flow when it is coincident. At the same time, the contact of the rigid diamond column can reliably transmit the axial load during work, preventing direct impact of the two-disc valve. Therefore, this structure optimizes the tribological performance and operation stability while ensuring the pulse generation function.

[0045] In some examples, the diamond support column 8 is fixed in the blind hole through a hot-embedding process.

[0046] In some embodiments, the upper joint 1 and the lower bit 10 are connected through a spline structure to transmit torque.

[0047] In some embodiments, the cutting teeth are PDC compacts, and the cutting teeth include cutting teeth with non-planar structures.

[0048] The present embodiment combines PDC compacts with non-planar structure teeth, which directly serves the goal of "eating soft and hard" and "self-adaptation". PDC compacts provide super-hard and wear-resistant cutting basis, ensuring efficient shearing in soft to medium-hard formations. Non-planar structure teeth (such as conical teeth) enhance impact resistance through their geometric shape, effectively concentrating impact stress on the tip when encountering hard inclusions, promoting rock fragmentation, and their bevels are beneficial for chip removal and stabilizing the wellbore. This hybrid tooth distribution strategy allows different structures of teeth to work together when facing complex and variable formations, with soft rock relying on shearing and hard rock relying on impact and crushing, achieving self-adaptive rock breaking capability for all rock properties and improving the overall performance and use range of the bit.

[0049] As an alternative to the present embodiment, the cutting teeth are not limited to PDC, but can also be other superhard materials, and the non-planar structure can also evolve into ridge-shaped, axe-shaped, or tooth shapes with anti-collapse designs such as pits, grooves, etc. In addition, cutting teeth of different sizes and different protrusion heights can also be arranged in different areas of the crown to optimize load distribution and cleaning effect.

[0050] The principles and implementation manners of the present application are described by using specific examples in the present application, and the above examples are only used to help understand the method of the present application and its core idea; meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation manners and application ranges will have changes. In summary, the content of the present description should not be understood as a limitation of the present application.

Claims

1. An integrated pulsating impact drilling bit, characterized by, The application relates to a drilling bit, comprising: a bit body, the crown of which is provided with cutting teeth for cutting and breaking rocks; a pulse generating mechanism, which is arranged in the bit body and is used for converting the energy of drilling fluid into periodic pressure pulses; wherein the periodic pressure pulses cause the bit body and the cutting teeth thereon to produce axial impact, so that synchronous cutting and breaking of rocks is realized.

2. The integrated pulsating impact drilling bit of claim 1, wherein: The pulse generating mechanism comprises an upper valve body and a lower valve body which are arranged in opposite rotation, and fluid channels are arranged on the upper valve body and the lower valve body respectively; the upper valve body is driven to rotate by the drilling fluid, so that the fluid channels on the two valve bodies are periodically overlapped and staggered, thereby generating the pressure pulses.

3. The integrated pulsating impact drilling bit of claim 2, wherein: The fluid channels of the upper valve body and the lower valve body are eccentrically arranged in arc-shaped holes of the upper valve body and the lower valve body.

4. The integrated pulsating impact drilling bit of claim 2, wherein: The structure for driving the upper valve body to rotate by the drilling fluid comprises: a fixed flow guiding unit which is fixedly arranged in the bit body and is used for guiding and accelerating the inflowing drilling fluid; a rotating impeller unit which is coaxially fixedly connected with the upper valve body and is located downstream of the fixed flow guiding unit, and is rotated by the drilling fluid guided by the fixed flow guiding unit, thereby driving the upper valve body.

5. The integrated pulsating impact drilling bit of claim 4, wherein: The rotating impeller unit is coaxially fixedly connected with the upper valve body through a torque transmission key.

6. The integrated pulsating impact drilling bit of claim 4, wherein: The bit body comprises an upper joint and a lower bit, and the pulse generating mechanism is arranged in a cavity formed by the connection of the upper joint and the lower bit.

7. The integrated pulsating impact drilling bit of claim 6, wherein: The fixed flow guiding unit is fixed to the lower bit through at least one positioning pin.

8. The integrated pulsating impact drilling bit of claim 3, wherein: Coaxial blind holes are arranged on the end faces of the upper valve body and the lower valve body, and diamond support columns are arranged in the blind holes; the two diamond support columns protrude from the blind holes, and the end faces of the two diamond support columns are abutted on the upper valve body and the lower valve body with a gap.

9. The integrated pulsating impact drilling bit of claim 6, wherein: The upper joint and the lower bit are connected through a toothing structure to transmit torque.

10. The integrated pulsating impact drilling bit of claim 1, wherein: The cutting teeth are PDC composite pieces, and the cutting teeth comprise cutting teeth with non-planar structures.

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