Intelligent PDC drill bit integrating pressure monitoring and data storage

Abstract

The invention discloses an intelligent PDC (Polycrystalline Diamond Compact) drill bit integrating pressure monitoring and data storage, which adopts an integrated design of integrating pressure measurement, analysis and storage, and solves the problems of insufficient real-time pressure monitoring and data storage of a traditional drill bit in high-temperature, high-pressure and complex stratums. Piezoelectric pressure sensors are integrated in cutting teeth of the drill bit to monitor stress changes of the drill bit in real time, and signals are amplified by a charge amplifier and then transmitted to a built-in storage module for data storage and preliminary analysis. A power source, a storage module and a signal processing module are integrated in the side face of the drill bit through windowing design, interference of external equipment is avoided, and operation stability is improved. High-temperature-resistant and high-pressure-resistant materials and a heat insulation technology are adopted, and it is ensured that the drill bit stably works in an extreme environment. The system has the advantages of being high in data collection real-time performance, high in anti-interference capacity and good in working stability, the safety and efficiency of drilling operation can be remarkably improved, and the system is widely suitable for being applied to complex environments such as deep well drilling and offshore drilling.

Description

Technical Field

[0001] This invention relates to the field of drilling tool technology, and in particular to an intelligent PDC drill bit that integrates pressure detection, data storage and intelligent analysis functions. Background Art

[0002] As one of my country's most important energy sources, petroleum plays a vital role in the country's modernization. With the increasing depth and complexity of petroleum resource development, traditional drilling technology faces numerous challenges. The downhole environment is complex and variable, frequently encountering problems such as formation pressure changes, tool wear, and drilling accidents. Currently, equipment for precise downhole pressure measurement is mainly concentrated on the drill pipe. This method not only results in data lag but also has a limited measurement range, failing to comprehensively reflect the bottom-hole conditions. Furthermore, data collected by traditional equipment must be wirelessly transmitted to the surface, and data loss or distortion is common under high temperature, high pressure, and strong vibration environments. Therefore, there is an urgent need for a new type of intelligent drill bit technology to achieve high-precision downhole pressure measurement and stable data storage, while simultaneously enhancing data analysis capabilities to optimize drilling efficiency and safety.

[0003] To change the above situation, the project described in this paper aims to develop an intelligent PDC drill bit that integrates pressure monitoring and data storage. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides an intelligent PDC drill bit integrating pressure monitoring and data storage. It integrates advanced pressure monitoring technology, aiming to provide superior performance and data acquisition capabilities in complex formations. The drill bit's sidewall and pressure-measuring cutting teeth design have been innovatively improved, optimizing its precise pressure measurement and storage capabilities while maintaining structural strength, providing crucial technical support for intelligent drilling technology.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A smart PDC drill bit integrating pressure monitoring and data storage includes a PDC drill bit body with six evenly distributed PDC drill bit blades on the body. Multiple PDC drill bit cutting teeth are provided on the cutting surfaces of the blades. The key feature is that each blade has a pressure-measuring cutting tooth. A piezoelectric sensor is located within the pressure-measuring cutting tooth. A wiring groove is provided inside the PDC drill bit, with the upper part connected to the piezoelectric sensor within the pressure-measuring cutting tooth and the lower part connected to a 32-bit microcontroller, an SD memory card, a charge amplification device, and a power supply located inside a detachable window milled into the side of the drill bit.

[0007] Furthermore, a piezoelectric sensor is nested in the middle of the cutting teeth of the PDC drill bit, which is machined into a hollow structure, to form a pressure-measuring cutting tooth.

[0008] Furthermore, the piezoelectric sensor consists of a top cover and a housing tightly coupled to form a hollow cylindrical structure. The housing is equipped with a lead wire interface connected to a wiring groove. The inner side contains a piezoelectric crystal, conductive sheets at both ends, and gaskets. The lead wire interface is sealed with rubber, and the final lead wire is connected to the outside.

[0009] Furthermore, the wiring channel is generally L-shaped, with its top connecting to the conductive sheet inside the piezoelectric sensor and its bottom connecting to the charge amplification device inside the detachable window.

[0010] A wire is connected to the side of the conductive sheet, and a lead interface is located on the side of the housing. The wire extends from the lead interface of the housing to the outside and finally connects to the 32 microcontroller, SD memory card, charge amplification device and power supply inside the removable window.

[0011] Furthermore, the removable window is milled into a stepped shape and sealed with a Viton fluororubber seal ring, and the external removable protective plate is connected with screws to maintain the internal and external seal of the removable window.

[0012] Furthermore, the pressure measuring cutting teeth are modified from the PDC drill bit cutting teeth in the PDC drill bit blades, specifically the PDC drill bit cutting teeth in the middle of each blade.

[0013] Furthermore, the wiring trough and the surface of the piezoelectric sensor are coated with a layer of ZS-411 high-temperature resistant coating, and all the wires connected to the piezoelectric sensor are coated with ZS-411 heat-insulating coating with a thickness of 0.6mm, which can withstand a high temperature of 400℃ and can meet the requirements of no less than 1000 hours of use in the well.

[0014] Furthermore, for the windowed portion on the drill bit body, the wires are fixed between the piezoelectric sensor and the electronic equipment using conductive adhesive. During the wiring process, special attention is paid to ensuring close contact between the wires and the piezoelectric sensor to guarantee the stability and reliability of signal transmission.

[0015] A working method for an intelligent PDC drill bit integrating pressure monitoring and data storage, comprising the following steps:

[0016] When the drill bit is working, the PDC drill bit cutting teeth on the PDC drill bit blades cut the formation. At this time, the cutting force is measured by the piezoelectric sensor on the pressure measuring cutting tooth, and the signal is transmitted to the charge amplification device in the window through the wire. The data processed by the 32 microcontroller is stored in the SD memory card and will be analyzed after being retrieved. The working power of the piezoelectric sensor is provided by the power supply in the window.

[0017] Based on the above technical solutions,

[0018] The present invention is beneficial in that:

[0019] Compared with the prior art, the advantages of the present invention are:

[0020] This paper discusses a project that modified the structure of the drill bit's window section and pressure-measuring cutting teeth, added a 32-bit microcontroller to enable real-time data analysis, and innovatively designed the installation and manufacturing possibilities of the drill bit window and pressure-measuring cutting teeth under actual working conditions. It overcame the challenges of high-temperature and high-pressure environments, achieving precise pressure measurement of the downhole formation. These design innovations not only improve the performance of the intelligent drill bit but also provide solid technical support for efficient drilling in directional drilling and complex formations. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0022] Figure 1 This is a schematic diagram of a smart PDC drill bit that integrates pressure monitoring and data storage.

[0023] Figure 2 An axial view of the assembly diagram for mounting a piezoelectric sensor on the drill bit body;

[0024] Figure 3 for Figure 2 Side view of;

[0025] Figure 4 for Figure 2 Cross-sectional view of the wiring trough section;

[0026] Figure 5 This is a design structure diagram of a piezoelectric sensor.

[0027] Figure 6 for Figure 5 Exploded view of the parts;

[0028] Figure 7 Exploded view of the detachable window section;

[0029] Figure 8 This is a connection diagram for a 32-bit microcontroller.

[0030] Figure 9 The image shows the piecewise discrete wavelet transform of the cutting force signal.

[0031] Figure 10 Flowchart of the overall assembly process for the PDC intelligent drill bit;

[0032] The meanings of the labels in the diagram are as follows:

[0033] 1-PDC drill bit body;

[0034] 2-PDC drill bit blades, 21-wiring groove;

[0035] 3-PDC drill bit cutting teeth, 31-pressure measuring cutting teeth, 311-piezoelectric sensor, 3111-top cover, 3112-conductive sheet, 3113-piezoelectric crystal, 3114-gasket, 3115-housing;

[0036] 4-Water eye;

[0037] 5-Removable window, 51-SD memory card, 52-charge amplification device, 53-power supply, 54-Removable protective plate, 55-32-microcontroller, 56-heat sink, 57-shockproof plate. DETAILED DESCRIPTION

[0038] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of 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, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0039] The embodiments of the present invention will be further described in detail below with reference to the accompanying drawings.

[0040] like Figure 1 , 2 As shown, an intelligent PDC drill bit integrating pressure monitoring and data storage includes a PDC drill bit body 1, with six evenly distributed PDC drill bit wings 2 on the drill bit body. Each PDC drill bit wing 2 has multiple PDC drill bit cutting teeth 3 and a pressure measuring cutting tooth 31. The pressure measuring cutting tooth 31 contains a piezoelectric sensor 311. A through-hole is provided in the middle of the PDC drill bit wing 2 as a wiring groove 21. The upper part of the wiring groove 21 is connected to the piezoelectric sensor 311 of the pressure measuring cutting tooth 31, and the lower part is connected to a detachable window 5 milled into the side of the drill bit. The piezoelectric sensor 311 is a specially customized miniature piezoelectric crystal, small in size to be embedded in the PDC drill bit cutting tooth 3. The piezoelectric sensor 311 is nested in the middle of the ordinary PDC drill bit cutting tooth 3 to form the pressure measuring cutting tooth 31.

[0041] Furthermore, the pressure measuring cutting tooth 31 is modified from the PDC drill bit cutting tooth 3 located in the middle of the PDC drill bit blade 2. Of course, other PDC drill bit cutting teeth 3 located on it can also achieve the detection effect, but being closer to the middle is the best option, as it has a longer service life.

[0042] Furthermore, the method of modifying the PDC drill bit cutting tooth 3 into a pressure-measuring cutting tooth 31 is as follows: a small opening is reserved in the PDC drill bit cutting tooth 3. In a low-temperature environment, the PDC drill bit cutting tooth 3 shrinks when it cools and the reserved opening widens. The piezoelectric sensor 311 is embedded in the reserved opening. When the PDC drill bit cutting tooth 3 is heated at room temperature or downhole temperature, it expands. The PDC drill bit cutting tooth 3 and the piezoelectric sensor 311 automatically achieve an interference fit, and the initial clamping force at this time is used as a compensation parameter and cleared to zero in the data. The pressure on the piezoelectric sensor 311 during cutting is the cutting force generated by the PDC drill bit cutting tooth 3.

[0043] like Figure 3 As shown, to ensure the drill bit's strength meets requirements and prevent damage to the drill bit body 1 during drilling, the slotted portion of the detachable side window 5 needs to be located in a non-critical stress area of ​​the drill bit body 1. During actual drilling, the PDC drill bit cutting teeth 3 are the main stress-bearing positions. Mechanical analysis of the main loads on the drill bit determines the window area. To ensure that the detachable window 5 does not weaken the strength of the drill bit body 1, the window depth needs to be controlled within a certain range, and a stepped arc-shaped groove design is adopted to effectively disperse stress concentration and reduce the negative impact on the strength of the drill bit body 1. This effectively utilizes the drill bit's window space while ensuring operational stability in complex formations. To meet the size requirements of the selected high-temperature resistant electronic components and the strength requirements of the drill bit itself, after repeated analysis and experiments, the final slot size was determined to be 77mm × 84mm × 50mm.

[0044] Furthermore, to prevent mud and other downhole impurities from entering the interior of the removable window 5, all slotted sections are sealed using Viton fluororubber sealing rings and screws to secure the removable guard plate 54, ensuring the system's sealing and durability.

[0045] Furthermore, during downhole operation, the drill bit body 1 is subjected to high-speed vibration. The high-frequency vibration and large amplitude changes will generate periodic forces acting on the screw connection. In order to prevent the screw from gradually loosening under stress, which would lead to a decrease in the stability of the window section, the window section uses a combination of flat washers and disc spring washers to increase the friction.

[0046] like Figure 4As shown, the wire of the piezoelectric sensor 311 needs to be connected to the conductive sheet 3112 and the detachable window 5. To reduce the impact of vibration generated when the drill bit breaks rock on the data transmission of the wire and to ensure the safety and durability of the wire during the drilling process, and to facilitate wiring, the wiring groove 21 needs to penetrate the inside of the drill bit body. The drill bit is grooved along the middle part of the PDC drill bit blade 2, with a depth of 10mm and a width of 5mm. The wire is then embedded in the groove inside the PDC drill bit blade 2. During the welding process between the PDC drill bit blade 2 and the drill bit body 1, its surface temperature will rise to over 300℃. To protect the wire, heat-insulating coating needs to be added. After the connection is completed, the high-temperature heat-insulating coating is immersed in the entire groove. After the coating solidifies, it can also play a fixing role, ensuring that it will not loosen due to vibration or impact during drilling.

[0047] like Figure 5 As shown in Figure 6, the connection between the upper cover 3111, conductive sheet 3112, piezoelectric crystal 3113, gasket 3114, and housing 3115 of the piezoelectric sensor 311 is achieved by conductive adhesive bonding. The connection between the conductive sheet 3112 and the wire is achieved by thermoforming. The entire housing cavity and the wire inlet and outlet are sealed with rubber. Before assembly, the upper cover 3111 and housing 3115 are also cleaned of oil and dirt. The inner surface of the pressure measuring cutting tooth 31 is coated with ZS-411 high-temperature resistant paint. The wire inlet and outlet on the end cover of the pressure measuring cutting tooth 31 are sealed with Viton fluororubber, and the empty space inside is filled with rubber.

[0048] Furthermore, a wire is connected to the side of the conductive sheet 3112, and a circular hole with a central opening is provided in the housing 3115. The wire passes through the hole in the housing 3115 and extends to the charge amplification device 52 inside the removable window 5. The processed data is stored in the SD memory card 51 and will be analyzed after being removed. The piezoelectric sensor 311 is powered by the power supply 53 inside the removable window 5. The diameter of the piezoelectric sensor 311 is 8mm, which is smaller than the diameter of the PDC drill bit cutting teeth 3.

[0049] like Figure 7 As shown, all built-in components and wires have undergone high-temperature resistance treatment. Before installation, the removable window 5 was filled with heat-insulating gel, providing good shock absorption and heat insulation performance. Meanwhile, the 32-bit microcontroller 55 has hollowed-out sides and is connected by threaded anti-vibration plates 57 on both sides. It is also coated with thermal grease and has heat sinks 56. The whole structure is made into a finned structure to ensure the stability of the system and long-term operation in the high-temperature environment downhole.

[0050] Furthermore, the charge amplification device 52 is an electronic circuit capable of converting the input charge signal into a voltage signal and amplifying it. It transforms the high-resistance charge source of the piezoelectric device into the low-resistance voltage source of the piezoelectric sensor 311, achieving impedance matching and ensuring that its output voltage is proportional to the input charge. Due to the weak nature of the charge signal generated by the piezoelectric sensor 311, it must be amplified by the charge amplifier 52 within the window to ensure sufficient signal strength for transmission to the 32-bit microcontroller 55 for further processing, preventing the original weak signal from being lost or distorted during transmission. The charge amplification device 52, through its designed shielding and grounding measures, effectively isolates external electromagnetic interference and prevents noise signals from entering the amplifier circuit through the power supply 52. ​​In addition, the differential input structure of the charge amplifier 52 significantly improves common-mode rejection capability, ensuring that only differential signals are effectively amplified, thereby reducing the impact of common environmental electromagnetic interference and ground noise on measurement accuracy.

[0051] like Figure 8 As shown, after receiving the amplified signal, the 32-bit microcontroller 55 performs preliminary processing and analysis. It uses the voltage and pressure correlation obtained from calibration tests to convert the electrical signal transmitted from the piezoelectric sensor 311 into a mechanical signal from the voltage signal output by the charge amplification device 52. Then, the data is transmitted to the SD memory card 51 via SPI communication. This data can be used for subsequent surface analysis or real-time monitoring of drilling conditions. Because the 32-bit microcontroller 55 and the SD memory card 51 need to be integrated into the removable window 5 of the drill bit body 1, this project systematically integrated the 32-bit microcontroller 55, rationally planned the PCB traces, reduced signal line lengths, simplified unrelated components, minimized its size, and improved its performance.

[0052] Furthermore, for the data from the 32-bit microcontroller 55 to be stored in the SD memory card 51, an SD memory card 51 read / write module is required. This module, using a Micro SD card reader / writer, integrates a Micro SD card slot, a voltage regulator circuit, a level conversion circuit, and six control interfaces. The voltage regulator circuit stably converts the input voltage to a voltage range suitable for the Micro SD card's operation, avoiding the impact of voltage fluctuations on storage stability. The level conversion circuit ensures level matching between the 32-bit microcontroller 55 and the SD memory card 51, guaranteeing the correctness and reliability of signal transmission. Through the cooperation of these two circuits, the 32-bit microcontroller 55 can communicate error-free with the SD memory card 51 module, effectively avoiding potential problems caused by power supply and signal mismatch. SPI, a high-speed serial interface, enables rapid data exchange between the 32-bit microcontroller 55 and the SD memory card 51, thus meeting the needs of real-time data storage and high-frequency read / write. The SD memory card 51, housed in the Micro SD card slot, is a non-volatile storage medium providing large-capacity data storage. The read / write module is connected to the 32 microcontroller 55. After the 32 microcontroller 55 converts the current signal into a mechanical signal, it will transmit the mechanical signal to the SD memory card 51 read / write module and store it in the SD memory card 51.

[0053] like Figure 9 This is a piecewise discrete wavelet transform of the acquired cutting force signal. The left side of the figure shows the cutting force signal decomposed into layers A5 to D1, and the right side shows the corresponding Fourier transform.

[0054] The method of using an intelligent PDC drill bit that integrates pressure monitoring and data storage using the above structure is as follows:

[0055] When the PDC drill bit body 1 is working, the PDC drill bit cutting teeth 3 on the PDC drill bit blades 2 cut the formation. At this time, the cutting force is measured by the piezoelectric sensor 311 on the pressure measuring cutting tooth 31, and the signal is transmitted to the charge amplification device 52 32 in the window 5 through the wire. The data processed by the microcontroller 55 32 is stored in the SD memory card 51 and will be analyzed after being retrieved. The piezoelectric sensor 311 is powered by the power supply 53 in the detachable window 5.

[0056] The specific requirements for construction shall be determined according to actual construction needs, and no specific restrictions shall be imposed in this application.

[0057] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0058] The foregoing is merely a list of specific embodiments of the present application, intended to enable those skilled in the art to understand or implement the present application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application is not limited to the embodiments shown herein, but is intended to conform to the broadest scope consistent with the principles and novel features of the present application.

Claims

1. An intelligent PDC drill bit with integrated pressure monitoring and data storage, comprising a PDC drill bit body (1), six evenly distributed PDC drill bit blades (2) are arranged on the drill bit body, and a plurality of PDC drill bit cutting teeth (3) are arranged on the cutting surface of the PDC drill bit blades, characterized in that: Each blade is provided with a pressure measuring cutting tooth (31); a piezoelectric sensor (311) is provided in the pressure measuring cutting tooth (31); a wiring groove (21) is provided in the PDC drill bit; the upper part of the wiring groove (21) is connected to the piezoelectric sensor (311) of the pressure measuring cutting tooth (31), and the lower part is connected to a detachable window (5) formed by milling on the side of the drill bit.

2. The intelligent PDC drill bit with integrated pressure monitoring and data storage according to claim 1, characterized in that: The piezoelectric sensor (311) is nested in the middle of a PDC drill bit cutting tooth (3) processed into a hollow structure, forming a pressure measuring cutting tooth (31).

3. The intelligent PDC drill bit with integrated pressure monitoring and data storage according to claim 1, characterized in that: The piezoelectric sensor (311) comprises an upper end cover (3111) and a shell (3116), wherein the upper end cover (3111) and the shell (3116) are tightly coupled to form a hollow cylindrical structure, wherein the shell (3116) is provided with a lead interface connected to a wiring groove (21), and a circular boss is provided on the inner side, and the circular boss can just contact the piezoelectric crystal (3113) near the end and the conductive sheet (3112) and gasket (3114) at both ends thereof.

4. The intelligent PDC drill bit with integrated pressure monitoring and data storage according to claim 1, characterized in that: The pressure measuring cutting tooth (31) for placing the piezoelectric sensor (311) has an upper top cover (3111) which is a cylinder with a thickness of 2 mm. The center of the cylinder has a protrusion with a threaded pattern. The protrusion height is 5 mm. The protrusion is used to provide a pre-tightening force to limit the axial freedom of the piezoelectric ceramic sheet, so that the piezoelectric crystal (3113) and the conductive sheet (3112) and the bottom of the shell fit tightly and provide a buffer. At the same time, the thread on the protrusion is connected with the thread of the shell (3115) to seal the sensor as a whole.

5. The intelligent PDC drill bit with integrated pressure monitoring and data storage according to claim 1, characterized in that: The detachable window (5) is connected to the wiring groove (21) of the pressure measuring cutting teeth (31) on three adjacent blade wings, wherein the extended wire is connected to the SD storage card (51), the charge amplifier device (52) 32 single chip microcomputer (55) and the power supply (53) inside the detachable window (5).

6. The intelligent PDC drill bit with integrated pressure monitoring and data storage according to claim 1, characterized in that: The upper part of the wiring groove (21) is connected to the conductive sheet (3112) inside the piezoelectric sensor (311) in the pressure measuring cutting tooth (31), and the lower part is connected to the detachable window (5).

7. The intelligent PDC drill bit with integrated pressure monitoring and data storage according to claim 1, characterized in that: The removable window (5) is milled into a stepped shape and a Viton fluororubber sealing ring and screws are used to fix the removable guard plate (54) to ensure the sealing and durability of the system.

8. The intelligent PDC drill bit with integrated pressure monitoring and data storage according to claim 1, characterized in that: The pressure measuring cutting teeth (31) are modified from the PDC drill bit cutting teeth (3) arranged in the PDC drill bit blade (2), and are modified from the PDC drill bit cutting teeth (3) in the middle of each blade.

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