Sound wave remote detection receiving sound system

Abstract

The invention discloses a sound wave remote detection receiving sound system, which is applied to the technical field of petroleum logging, and is characterized in that adjacent sound wave detection receiving units are fixedly connected through a sound insulation cover, and the sound insulation cover forms a sound insulation cavity between the adjacent sound wave detection receiving units; the sound wave detection receiving unit comprises a columnar framework, and a pressure-bearing bin is arranged in the framework; a plurality of receiving transducer assemblies which are evenly distributed in the circumferential direction are arranged on the periphery of the framework, a pre-receiving circuit board assembly is arranged in the pressure bearing bin, and the receiving transducer assemblies are electrically connected with the pre-receiving circuit board assembly. By arranging the receiving pre-amplification circuit board assembly in the skeleton, an electric signal collected by the receiving transducer assembly can be transmitted to the pre-amplification circuit board assembly for signal filtering optimization and amplification enhancement only through a short distance, so that the sound wave receiver has a high signal-to-noise ratio. And sound isolation between the adjacent sound wave detection receiving units can be ensured through the arrangement of the sound insulation cover.

Description

Technical Field

[0001] This invention relates to the field of oil well logging technology, and in particular to a acoustic long-range detection receiving system. Background Technology

[0002] Conventional acoustic long-range detection systems consist of multiple sets of multi-pole receiving units, each composed of two multi-pole piezoelectric ceramic plates connected in parallel in various directions. However, as wellbore depth increases, downhole pressure and temperature rise, causing a sharp decline in the sensitivity and performance of these piezoelectric ceramics. This makes it impossible to accurately receive acoustic signals, especially in deep wells, and hinders the acquisition of effective acoustic signals in the increasingly common horizontal and highly deviated well measurements. Therefore, providing a method to achieve a high signal-to-noise ratio for acoustic long-range detection signals under the high temperature and pressure environment of deep wells is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0003] The purpose of this invention is to provide a sound wave remote detection receiving system that can achieve a high signal-to-noise ratio for sound wave remote detection signals in deep well high temperature and high pressure environments.

[0004] To solve the above-mentioned technical problems, the present invention provides a sound wave remote detection and receiving system, including at least two sound wave detection and receiving units and a soundproof cover located between two adjacent sound wave detection and receiving units; the adjacent sound wave detection and receiving units are fixedly connected by the soundproof cover, and the soundproof cover forms an acoustic isolation cavity between the adjacent sound wave detection and receiving units.

[0005] The acoustic wave detection and receiving unit includes a columnar frame with a pressure chamber inside; a plurality of receiving transducer assemblies are evenly distributed along the circumferential direction on the outer periphery of the frame, and a receiving preamplifier circuit board assembly is disposed inside the pressure chamber. The receiving transducer assemblies are electrically connected to the receiving preamplifier circuit board assembly.

[0006] Optionally, the pressure chamber has an opening at one end and a bottom at the other end along the axial direction of the frame;

[0007] The receiving preamplifier circuit board assembly includes a preamplifier circuit board and a pressure-bearing block welded to the preamplifier circuit board, wherein the pressure-bearing block is sealed to the opening of the pressure-bearing chamber.

[0008] Optionally, the pressure block is provided with a connector that penetrates the pressure block along the axial direction. The end of the connector near the preamplifier circuit board is soldered to the gold finger of the preamplifier circuit board, and the end of the connector away from the preamplifier circuit board protrudes from the surface of the pressure block.

[0009] Optionally, it also includes a socket located on the side of the pressure block away from the front circuit board, wherein the female connector in the socket is connected to the corresponding connector;

[0010] The socket has a tie post extending along the axial direction on the surface away from the pressure block.

[0011] Optionally, it also includes a housing and high-temperature oil located inside the housing; the acoustic wave detection and receiving unit and the soundproof cover are located inside the housing and immersed in the high-temperature oil.

[0012] Optionally, the housing is provided with a reinforcing grid corresponding to the position of the receiving transducer assembly.

[0013] Optionally, the housing surface is provided with a spacer, the top of which protrudes from the housing surface.

[0014] Optionally, the surface of the gapper is provided with sound-absorbing holes.

[0015] Optionally, the receiving transducer assembly includes two stacked piezoelectric ceramic sheets, which are polarized along the thickness direction;

[0016] The positive electrode side surface of one piezoelectric ceramic sheet is in contact with and electrically connected to the negative electrode side surface of another piezoelectric ceramic sheet, so that the two piezoelectric ceramic sheets are connected in series.

[0017] Optionally, the receiving transducer assembly further includes a negative electrode conductive sheet and a positive electrode conductive sheet, wherein the negative electrode conductive sheet is bonded to the exposed negative electrode side surface of the two stacked piezoelectric ceramic sheets, and the positive electrode conductive sheet is bonded to the exposed positive electrode side surface of the two stacked piezoelectric ceramic sheets.

[0018] The present invention provides a sound wave remote detection and receiving system, comprising at least two sound wave detection and receiving units and a soundproof enclosure located between two adjacent sound wave detection and receiving units; the adjacent sound wave detection and receiving units are fixedly connected by the soundproof enclosure, and the soundproof enclosure forms an acoustic isolation cavity between the adjacent sound wave detection and receiving units; the sound wave detection and receiving unit includes a columnar frame, and a pressure-bearing chamber is provided inside the frame; a plurality of receiving transducer assemblies are provided on the outer periphery of the frame and evenly distributed in the circumferential direction; a receiving preamplifier circuit board assembly is provided inside the pressure-bearing chamber; the receiving transducer assemblies are electrically connected to the receiving preamplifier circuit board assembly.

[0019] By placing a receiving preamplifier circuit board assembly inside the frame, the receiving transducer assembly can be electrically connected to the preamplifier circuit board assembly in close proximity. This allows the electrical signal collected by the receiving transducer assembly to be transmitted to the preamplifier circuit board assembly for signal filtering, optimization, and amplification over a very short distance. This effectively improves signal quality and anti-interference performance, resulting in a high signal-to-noise ratio for the acoustic receiver. Furthermore, the soundproof enclosure ensures acoustic isolation between adjacent acoustic detection and receiving units, preventing mutual interference. Attached Figure Description

[0020] To more clearly illustrate the technical solutions of the embodiments of the present invention or the prior art, 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 the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a partial structural diagram of a sound wave remote detection receiving acoustic system provided in an embodiment of the present invention;

[0022] Figure 2 for Figure 1 A schematic diagram of the structure of the acoustic wave detection and receiving unit;

[0023] Figure 3 This is a schematic diagram of a specific acoustic wave remote detection and receiving system.

[0024] Figure 4 This is a schematic diagram of a specific receiving preamplifier circuit board assembly provided in an embodiment of the present invention;

[0025] Figure 5 This is a schematic diagram of the structure of a specific receiving transducer assembly provided in an embodiment of the present invention;

[0026] Figure 6 A comparison graph of the sensitivity of the receiving transducer components;

[0027] Figure 7 This is a partial schematic diagram of an acoustic wave detection and receiving unit provided in an embodiment of the present invention;

[0028] Figure 8 This is a schematic diagram of a preamplifier circuit provided in an embodiment of the present invention;

[0029] Figure 9 This is a comparison diagram of acoustic wave reception signals with and without a preamplifier circuit.

[0030] In the diagram: 1. Acoustic wave detection and receiving unit; 2. Soundproof enclosure; 3. Receiver lead wire cover; 4. Reinforced grid; 5. Housing; 6. High-temperature oil; 7. Sheath; 8. Load-bearing block; 12. Gap element; 14. Threaded sleeve; 15. Upper connector clamp; 16. Housing retaining ring; 17. Housing sealing ring; 32. Silencing hole;

[0031] 102. Receiving transducer assembly; 104. Frame; 105. Receiving preamplifier circuit board assembly; 106. Pressure chamber; 107. Socket; 108. Cover plate; 109. Cable tie post;

[0032] 21. Fixing sleeve; 22. Screw; 211. Negative electrode conductive sheet; 212. Conductive adhesive; 213. Piezoelectric ceramic sheet; 214. Positive electrode conductive sheet;

[0033] 51. Front-end circuit board, 52. Pressure block, 53. Sealing ring, 54. Retaining ring, 55. Connector, 56. Insulation layer, 57. Soldering material, 58. Sealing disc, 59. Screw hole. Detailed Implementation

[0034] The core of this invention is to provide a long-range acoustic detection receiving system. In existing technologies, deep wells are characterized by high temperature and high pressure, and the receiving structures of long-range acoustic detection receiving systems applied to these wells currently suffer from low sensitivity and low signal-to-noise ratio.

[0035] The acoustic wave detection and receiving system provided by the present invention includes at least two acoustic wave detection and receiving units and a soundproof enclosure located between two adjacent acoustic wave detection and receiving units; the adjacent acoustic wave detection and receiving units are fixedly connected by the soundproof enclosure, and the soundproof enclosure forms an acoustic isolation cavity between the adjacent acoustic wave detection and receiving units; the acoustic wave detection and receiving unit includes a columnar frame, and a pressure-bearing chamber is provided inside the frame; a plurality of receiving transducer assemblies are provided on the outer periphery of the frame and evenly distributed in the circumferential direction; a receiving preamplifier circuit board assembly is provided in the pressure-bearing chamber; and the receiving transducer assemblies are electrically connected to the receiving preamplifier circuit board assembly.

[0036] By placing a receiving preamplifier circuit board assembly inside the frame, the receiving transducer assembly can be electrically connected to the preamplifier circuit board assembly in close proximity. This allows the electrical signal collected by the receiving transducer assembly to be transmitted to the preamplifier circuit board assembly for signal filtering, optimization, and amplification over a very short distance. This effectively improves signal quality and anti-interference performance, resulting in a high signal-to-noise ratio for the acoustic receiver. Furthermore, the soundproof enclosure ensures acoustic isolation between adjacent acoustic detection and receiving units, preventing mutual interference.

[0037] To enable those skilled in the art to better understand the present invention, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Obviously, the described embodiments are merely 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.

[0038] Example 1

[0039] Please refer to Figures 1 to 3 , Figure 1 This is a partial structural diagram of a sound wave remote detection receiving acoustic system provided in an embodiment of the present invention; Figure 2 for Figure 1A schematic diagram of the structure of the acoustic wave detection and receiving unit; Figure 3 This is a schematic diagram of a specific acoustic wave remote detection and receiving system.

[0040] See Figure 1 In this embodiment of the invention, the acoustic wave remote detection and receiving system includes at least two acoustic wave detection and receiving units 1 and a soundproof cover 2 located between two adjacent acoustic wave detection and receiving units 1; the adjacent acoustic wave detection and receiving units 1 are fixedly connected by the soundproof cover 2, and the soundproof cover 2 forms an acoustic isolation cavity between the adjacent acoustic wave detection and receiving units 1; the acoustic wave detection and receiving unit 1 includes a columnar frame 104, and a pressure-bearing chamber 106 is provided inside the frame 104; a plurality of receiving transducer assemblies 102 are provided on the outer periphery of the frame 104 and evenly distributed in the circumferential direction; a receiving preamplifier circuit board assembly 105 is provided in the pressure-bearing chamber 106, and the receiving transducer assembly 102 is electrically connected to the receiving preamplifier circuit board assembly 105.

[0041] In this embodiment, the acoustic wave remote detection and receiving system is typically cylindrical in shape, thus possessing three directions: axial, circumferential, and radial. Multiple acoustic wave detection and receiving units 1 within the system are usually arranged along the axial direction. Each acoustic wave detection and receiving unit 1 is a component that receives acoustic signals and generates electrical signals. A soundproof enclosure 2 located between two adjacent acoustic wave detection and receiving units 1 is used to achieve acoustic isolation between them. Specifically, the soundproof enclosure 2 forms an acoustic isolation cavity between adjacent acoustic wave detection and receiving units 1, thereby achieving acoustic isolation between the units.

[0042] A receiving lead wire cover 3 can be provided on the surface of the acoustic wave detection and receiving unit 1. It is usually located near the receiving transducer assembly 102. The receiving lead wire cover 3 has a wire routing channel, which serves two purposes: firstly, to guide the leads from the receiving transducer assembly 102, ensuring that all leads of the receiving transducer assembly 102 are of equal length and arranged in an alternating pattern; secondly, to protect the leads from being pressed or squeezed by the bladder 7, the acoustic wave detection and receiving unit 1, the soundproof enclosure 2, and other components. At the same time, it can improve the reliability of reception and the consistency of the signal. The material of the receiving lead wire cover 3 is usually antimagnetic gold. The acoustic wave detection and receiving unit 1 can be fixedly connected to the acoustic wave detection and receiving unit 2 by screws; the acoustic wave detection and receiving unit 1 and the soundproof cover 2 can be connected by a headless threaded screw. On the one hand, this can reduce the noise and vibration caused by the acoustic wave detection and receiving system hitting the well wall. On the other hand, it can reduce the stress from the acoustic wave detection and receiving unit 1 and the soundproof cover 2 to effectively protect the soundproof cover 2 and effectively attenuate the mechanical vibration of the acoustic wave detection and receiving unit 1. This can effectively improve the reception quality of acoustic wave signals and reduce the reception of useless signals, thereby improving the reliability of reception.

[0043] See Figure 2The aforementioned acoustic wave detection and receiving unit 1 includes a columnar frame 104, which is the main load-bearing structure of the acoustic wave detection and receiving unit 1. It is typically columnar, thus having three directions: axial, circumferential, and radial. The frame 104 needs to be electromagnetically shielded to ensure the performance of the acoustic wave detection and receiving unit 1. Specifically, the main body of the frame 104 can be made of stainless steel electromagnetic shielding metal, meaning the frame 104 can be a stainless steel electromagnetically shielded frame 104. This material results in a large frame 104, which can prevent vibrations generated during acoustic wave signal reception from causing noise to the receiving transducer assembly 102 when receiving acoustic wave signals, thereby further improving the acoustic wave signal quality of the multipole acoustic wave receiving unit. The electromagnetic shielding material can prevent electromagnetic signals generated during acoustic wave transmission from interfering with the high-precision reception of the receiving transducer assembly 102, thus improving the quality of the received signal. Of course, in this embodiment, the specific material of the frame 104 is not specifically limited and depends on the specific circumstances. In this embodiment, the diameter of the skeleton 104 is typically less than 70 mm to ensure that the receiving device composed of the acoustic wave detection receiving unit 1 can be effectively used in wellbore environments with a diameter of 120 mm or less.

[0044] The outer periphery of the aforementioned skeleton 104 is provided with a plurality of receiving transducer assemblies 102 evenly distributed along the circumferential direction. Typically, four, six, or eight receiving transducer assemblies 102 are evenly distributed along the circumferential direction. Specifically, four receiving transducer assemblies 102 can form a four-component receiving transducer assembly 102, which is typically evenly distributed at 90° intervals along the circumference; six receiving transducer assemblies 102 can form a six-component receiving transducer assembly 102, which is typically evenly distributed at 60° intervals along the circumference; and eight receiving transducer assemblies 102 can form an eight-component receiving transducer assembly 102, which is typically evenly distributed at 45° intervals along the circumference. The number of receiving transducer assemblies 102 is not specifically limited in this embodiment and depends on the specific circumstances. The aforementioned receiving transducer assembly 102 is the main body for receiving acoustic signals, and it typically converts acoustic wave fluctuation signals into electrical signals through the piezoelectric ceramic sheet 213 within it. The specific structure of the receiving transducer assembly 102 will be described in detail in the following embodiments of the invention, and will not be repeated here.

[0045] The aforementioned pressure chamber 106 is a cavity formed by a radially central opening within the skeleton 104. It is used to accommodate the receiving preamplifier circuit board assembly 105. The pressure chamber 106 has an opening at the upper part along the axis of the skeleton 104 and is sealed at the lower part. The distance between the outer boundary of the pressure chamber 106 and the outer surface of the skeleton 104 is typically not less than 7 mm. This ensures that after the receiving preamplifier circuit board assembly 105 is placed inside the pressure chamber 106, the outer wall of the pressure chamber 106 can withstand a pressure of 250 MPa underground, protecting the receiving preamplifier circuit board assembly 105 from damage caused by the high pressure underground. The specific structure of the receiving preamplifier circuit board assembly 105, placed within the pressure chamber 106, will be described in detail in the following embodiments of the invention and will not be repeated here. In this embodiment, since the receiving preamplifier circuit board assembly 105 is located in the pressure chamber 106 which is very close to the receiving transducer assembly 102, the electrical signal generated by the receiving transducer assembly 102 can be transmitted to the receiving preamplifier circuit board assembly 105 for filtering, amplification and other processing, thereby improving the performance of the sound wave remote detection receiving system.

[0046] See Figure 3 In this embodiment, the acoustic wave remote detection and receiving system typically includes a housing 5 and high-temperature oil 6 located within the housing 5. The acoustic wave detection and receiving unit 1 and the soundproof cover 2 are located within the housing 5 and immersed in the high-temperature oil 6. This high-temperature oil 6 is typically a low-compression-ratio, high-boiling-point electrically insulating high-temperature oil, used to protect the internal structure of the acoustic wave remote detection and receiving system in deep pit and deep well environments. The high-temperature oil 6, the acoustic wave detection and receiving unit 1 immersed in the high-temperature oil 6, and the soundproof cover 2 are typically isolated and sealed by a bladder 7, with the aforementioned housing 5 fixed outside the bladder 7. This housing 5 needs to be a sound-permeable housing 5, and its material is typically high-strength metal. The specific material of the housing 5 can be determined according to actual conditions and is not specifically limited here.

[0047] The aforementioned outer casing 5 is provided with a reinforcing grid 4 at the position corresponding to the receiving transducer assembly 102. This reinforcing grid 4 typically has high strength and a certain gap to allow sound waves to pass through. Its effect is twofold: firstly, it effectively protects the inner structure of the reinforcing grid 4, which can typically withstand tensile and compressive forces exceeding 30,000 kg to ensure stable and reliable construction and measurement of the acoustic remote detection receiving system under horizontal well conditions; secondly, it prevents sharp foreign objects in the well from tearing the casing 7 and damaging the acoustic remote detection receiving system; and thirdly, it effectively ensures the efficient entry of acoustic signals into the receiving transducer assembly 102 for reception. It also effectively couples acoustic signals to the receiving transducer assembly 102. This structure can typically withstand downhole pressure of 250 MPa, effectively resisting the erosion of high temperature, high pressure, and corrosive gases and liquids downhole, and has good sound transmission performance, ensuring the quality and reliability of acoustic signal reception.

[0048] In this embodiment, the outer casing 5 is typically divided into an upper, middle, and lower section along the axial direction. The upper section of the outer casing 5 is usually equipped with a circumferentially arranged outer casing retaining ring 16 and an outer casing sealing ring 17. These two components work together to isolate the interior of the acoustic wave remote detection receiving system from the liquid in the wellbore, effectively preventing the receiving transducer assembly 102 from direct contact with the well liquid and thus avoiding damage. This also prevents the well liquid from corroding and protecting the charged parts in the acoustic wave detection receiving unit 1. Furthermore, it effectively reduces the vibration generated by the instruments connected vertically in the well, thereby achieving a good acoustic wave reception effect. An upper connector block 15 is usually provided on the upper section of the outer casing 5, which is used for high-precision connection and positioning with the receiving acquisition line section, ensuring that the connection and positioning deviation between the two is less than 0.5°, resulting in higher azimuth resolution during azimuth detection.

[0049] In this embodiment, a spacer 12 is provided on the surface of the outer shell 5, with the top of the spacer 12 protruding from the surface of the outer shell 5. The spacer 12 is typically embedded in the surface of the outer shell 5, with its top protruding slightly higher than the surface of the outer shell 5. The spacer 12 is typically cast from a perfluoroelastomer rubber body, with a high-strength, wear-resistant metal grid embedded inside. It is arranged in a hollow cylindrical shape and fitted onto the surface of the outer shell 5, usually at the top or bottom of the acoustic wave detection and receiving unit 1. This design allows the acoustic wave detection and receiving system to be kept away from the wellbore and avoid direct contact with the wellbore, thus preventing vibration. It also ensures that the acoustic wave detection and receiving system is as close to the center of the wellbore as possible, guaranteeing measurement effectiveness and quality. Furthermore, the use of perfluoroelastomer rubber as the main material reduces vibration or noise caused by collisions with the spacer 12, improving logging quality. The high-strength, wear-resistant metal grid effectively extends the lifespan of the spacer 12.

[0050] Furthermore, in this embodiment, the surface of the spacer 12 is provided with a noise-absorbing hole 32. The noise-absorbing hole 32 is usually located in the radial direction of the spacer 12, that is, the axis of the noise-absorbing hole 32 is usually perpendicular to the surface of the outer shell 5. The noise-absorbing hole 32 is used to further attenuate the vibration and noise generated by the collision with the well wall. Usually, multiple noise-absorbing holes 32 are provided in the spacer 12 in a regular arrangement.

[0051] In this embodiment, the connection between different components of the outer shell 5 can be achieved using threaded sleeves 14. This ensures the ease of disassembly of instrument components and effectively attenuates vibrations caused by collisions in the acoustic detection and receiving system, thereby improving the quality of the received acoustic signal. A load-bearing block 8 is typically provided in the outer shell 5. This block connects the outer shell 5 to various internal components, such as the acoustic detection and receiving unit 1, and the soundproof enclosure 2. This ensures that the internal components of the outer shell 5 are not affected by the tensile and compressive forces of the drill bit during measurement, protecting the more vulnerable components within the acoustic receiver body, such as the acoustic detection and receiving unit 1, the soundproof enclosure 2, and the connected upper and lower connectors, which are encased in the bladder 7. Compared to traditional screw fixing methods, this method offers a larger contact area, a simpler structure, and generally twice the tensile and compressive strength of screws.

[0052] The acoustic wave remote detection and receiving system provided in this embodiment, by setting a receiving preamplifier circuit board assembly 105 inside the frame 104, allows the receiving transducer assembly 102 to be close to and electrically connected to the receiving preamplifier circuit board assembly 105. This enables the electrical signal collected by the receiving transducer assembly 102 to be transmitted to the receiving preamplifier circuit board assembly 105 for signal filtering optimization and amplification enhancement over a very short distance. This effectively improves signal quality and anti-interference performance, giving the acoustic wave receiver a high signal-to-noise ratio. The soundproof enclosure 2 ensures acoustic isolation between adjacent acoustic wave detection and receiving units 1, preventing them from interfering with each other.

[0053] The specific details of the acoustic wave detection and receiving unit 1 provided by the present invention will be described in detail in the following embodiments.

[0054] Example 2

[0055] Please refer to Figure 4 , Figure 4 This is a schematic diagram of a specific receiving preamplifier circuit board assembly provided in an embodiment of the present invention.

[0056] Unlike the embodiments described above, the embodiments of the present invention further define the structure of the acoustic wave detection and receiving unit 1 based on the embodiments described above. The remaining details have been described in detail in the embodiments described above and will not be repeated here.

[0057] See Figure 4 In this embodiment of the invention, the pressure chamber 106 has an opening at one end and a bottom at the other end along the axial direction of the skeleton 104; the receiving preamplifier circuit board assembly 105 includes a preamplifier circuit board 51 and a pressure block 52 welded to the preamplifier circuit board 51, and the pressure block 52 is sealed to the opening of the pressure chamber 106.

[0058] The aforementioned receiving preamplifier circuit board assembly 105 is placed inside the pressure chamber 106. This assembly typically includes at least a preamplifier circuit board 51 and a pressure block 52 welded to it. It also usually includes a sealing ring 53, a retaining ring 54, a connector 55, an insulating layer 56, solder 57, a sealing disc 58, screw holes 59, and other structures. In this embodiment, to ensure the reliability and stability of the receiving preamplifier circuit board assembly 105, the preamplifier circuit board 51 is typically less than 50mm in length and less than 20mm in width. It employs a simple single-layer board design, minimizing the number of components. Preferably, it only includes three types of components: high-temperature surface mount resistors, high-temperature surface mount capacitors, and high-temperature multi-channel low-power operational amplifiers. Its main function is to filter and enhance the electrical signal converted from the receiving transducer assembly 102, improving signal quality and anti-interference capabilities.

[0059] The aforementioned pressure-bearing block 52 is sealed to the opening of the pressure chamber 106, ensuring that the front-end circuit board 51 installed inside the pressure chamber 106 is not corroded by external high-pressure liquid, thus effectively protecting the circuit board. Specifically, at least one sealing ring 53 is provided around the outer periphery of the pressure-bearing block 52 in the circumferential direction. In this embodiment, two sealing rings 53 are preferably provided, which can be perfluoroether sealing rings 53, used to achieve sealing and isolation at both ends of the pressure-bearing block 52, ensuring that the pressure-bearing block 52 can be sealed to the opening of the pressure chamber 106. Furthermore, in this embodiment, a retaining ring 54 can be provided between the sealing ring 53 and the pressure-bearing block 52. This retaining ring 54 can be a high-temperature PEEK retaining ring 54, which is used to ensure that the radial compression of the sealing ring 53 is not too large during high-pressure sealing, so as to ensure the sealing effectiveness under high-pressure environment.

[0060] In this embodiment, the first end of the preamplifier circuit board 51 is fixedly connected to the pressure block 52. A sealing disc 58 is provided at the second end of the preamplifier circuit board 51 opposite to the first end. A slot is provided on the surface of the sealing disc 58, and the second end of the preamplifier circuit board 51 is inserted into the slot. The sealing disc 58 can be a disc made of PTFE (polytetrafluoroethylene) material. The sealing disc 58 has a straight slot that runs through the center of the disc. The slot can be tightly inserted into the end of the preamplifier circuit board 51. That is, the pressure block 52 can be specifically located at the first end of the preamplifier circuit board 51, and the sealing disc 58 is located at the end of the preamplifier circuit board 51. PTFE material has good ductility, which can effectively avoid the adverse effects of tension caused by the expansion and contraction of the preamplifier circuit board 51 due to high temperature on its circuit. This further ensures that the preamplifier circuit board 51 does not deform at high temperature, improves the reliability and stability of the preamplifier circuit board 51, and can also reduce the vibration of the preamplifier circuit board 51 in the well, playing a shock absorption and buffering role to further protect the preamplifier circuit board 51 and improve its reliability and stability.

[0061] In this embodiment, the pressure block 52 is provided with a connector 55 that penetrates the pressure block 52 along the axial direction. One end of the connector 55 near the preamplifier circuit board 51 is soldered to the gold finger of the preamplifier circuit board 51, and the other end of the connector 55 away from the preamplifier circuit board 51 protrudes from the surface of the pressure block 52.

[0062] The connector 55 is mainly used to realize the electrical connection between the preamplifier circuit board 51 and the outside. The end of the connector 55 that extends into the pressure chamber 106, that is, the end near the preamplifier circuit board 51, is the inner plug. The inner plug is usually the end with solder cups. At least some of the inner plugs of the connector 55, such as the inner plugs in the middle two rows, can make close contact with the gold finger pads on the upper and lower surfaces of the preamplifier circuit board 51. This structure can ensure a good connection. On the other hand, the solder 57 located at the end of the connector 55 near the preamplifier circuit board 51 melts when soldering with the preamplifier circuit board 51 to further enhance the strength of the connection between the preamplifier circuit board 51 and the connector 55. The other solder cups of the inner plug of the connector 55 can be electrically connected to the preamplifier circuit board 51 by melting the high-temperature solder 57 with high-temperature wires. This can ensure the firmness of its electrical connection and good shock resistance, thereby improving reliability. The connector 55 is usually a high-temperature gold-plated connector 55. Of course, its material is not specifically limited in this embodiment and depends on the specific situation.

[0063] In this embodiment, an insulating layer 56 is provided between the pressure block 52 and the connector 55. This insulating layer 56 can be a high-temperature engineering ceramic to form electrical insulation between the connector 55 and the pressure block 52, ensuring that the signal flowing through the connector 55 flows normally without short-circuiting to the pressure block 52. The screw holes 59 provided on the pressure block 52 are used for removing the receiving preamplifier circuit board assembly 105, that is, removing the receiving preamplifier circuit board assembly 105 from the pressure chamber 106 using a special tool. The main body of the pressure block 52 is usually made of high-strength stainless steel electromagnetic shielding material.

[0064] This embodiment also includes a socket 107 located on the side of the pressure block 52 away from the preamplifier circuit board 51. The female connector in the socket 107 is connected to the connector 55. The end of the connector 55 away from the preamplifier circuit board 51, that is, the end protruding from the surface of the pressure block 52 away from the preamplifier circuit board 51, is typically an external male connector. This external male connector is connected to the socket 107, such as an 18-pin socket 107, and in this case, the socket 107 is located on the side of the pressure block 52 away from the preamplifier circuit board 51. The socket 107 contains a female connector, such as an 18-pin gold-plated female connector. This female connector is connected to the external male connector in the connector 55. A retainer can be provided inside the female connector to ensure a good electrical connection with the external male connector. Additionally, a cover plate 108, such as a stainless steel cover plate 108, can be provided on the side of the socket 107 away from the front circuit board 51. In this case, the cover plate 108 can be used to press the socket 107 firmly through a connecting structure such as screws. This can ensure a tight connection between the male and female connectors on the one hand, and ensure that the female connector does not detach from the external male connector due to the force of the connecting wires on the other hand, thereby improving the reliability of the connection.

[0065] In this embodiment, the surface of the socket 107 away from the pressure block 52 is provided with a wire tie post 109 extending along the axial direction. The wire tie post 109 is usually arranged at the center of the socket 107 to fix and bundle the wires soldered to the socket 107 solder cup. The wire tie post 109 is used for compact wiring, saving space and effectively protecting the wires from being crushed or damaged by external connectors.

[0066] During downhole logging, the acoustic wave detection receiving unit 1 is usually immersed in high-temperature insulating oil. This ensures that the pressure and temperature at the outer edge of the acoustic wave detection receiving unit 1 are the same as the temperature and pressure downhole. Meanwhile, the pressure chamber 106 can be kept at normal pressure, effectively preventing the preamplifier circuit board 51 from being exposed to high pressure. This greatly improves its reliability and stability in the high-pressure environment of deep wells. The pressure block 52 can be made of electromagnetically shielded stainless steel. This material can effectively shield electromagnetic interference generated by the sound source emission, further improving the accuracy of the receiving signal amplification circuit.

[0067] The acoustic wave detection and receiving unit 1 provided in this embodiment has a receiving preamplifier circuit board assembly 105 set in a pressure chamber 106 inside a frame 104 and sealed by a pressure block 52, so that the receiving preamplifier circuit board assembly 105 can be used in deep well high temperature and high pressure environments.

[0068] The specific details of the acoustic wave detection and receiving unit 1 provided by the present invention will be described in detail in the following embodiments.

[0069] Example 3

[0070] Please refer to Figures 5 to 9 , Figure 5This is a schematic diagram of the structure of a specific receiving transducer assembly provided in an embodiment of the present invention; Figure 6 A comparison graph of the sensitivity of the receiving transducer components; Figure 7 This is a partial schematic diagram of an acoustic wave detection and receiving unit provided in an embodiment of the present invention; Figure 8 This is a schematic diagram of a preamplifier circuit provided in an embodiment of the present invention; Figure 9 This is a comparison diagram of acoustic wave reception signals with and without a preamplifier circuit.

[0071] Unlike the embodiments described above, the embodiments of the present invention further define the structure of the receiving transducer assembly 102 based on the embodiments described above. The remaining details have been described in detail in the embodiments described above and will not be repeated here.

[0072] See Figure 5 In this embodiment of the invention, the receiving transducer assembly 102 includes two piezoelectric ceramic sheets 213 stacked together, the piezoelectric ceramic sheets 213 being polarized along the thickness direction; the positive electrode side surface of one piezoelectric ceramic sheet 213 is in contact with and electrically connected to the negative electrode side surface of the other piezoelectric ceramic sheet 213, so that the two piezoelectric ceramic sheets 213 are connected in series.

[0073] In this embodiment, the main structure of the receiving transducer assembly 102 consists of two piezoelectric ceramic sheets 213 connected in series. In this embodiment, the piezoelectric ceramic sheets 213 are polarized along their thickness direction; therefore, one surface is the positive electrode side surface, and the other surface is the negative electrode side surface. In this embodiment, the positive electrode side surface of one piezoelectric ceramic sheet 213 contacts and is electrically connected to the negative electrode side surface of the other piezoelectric ceramic sheet 213. That is, the two piezoelectric ceramic sheets 213 are stacked, and the two contacting surfaces are surfaces with opposite electrical polarities, thus connecting the two piezoelectric ceramic sheets 213 in series.

[0074] As shown in the table below, under the same conditions, compared with the parallel method, the capacitance of the receiving transducer assembly 102 in the series method is reduced by three-quarters, the driving capability of the cable is reduced, and the ability to connect long cables is weakened, but the sensitivity is doubled. This is extremely advantageous for instruments that detect weak reflected signals from distant sound waves. To address the reduction in cable driving capability, this embodiment sets up a receiving preamplifier circuit board assembly 105 near the receiving transducer assembly 102, which can significantly reduce the cable length for receiving sound waves and eliminate the adverse effects of weak driving. In addition, the addition of the preamplifier circuit can greatly improve the quality of the received signal, with the original received signal sensitivity increasing by 6 dB and the signal anti-interference capability also improved.

[0075] Table 1. Comparison of Series and Parallel Connections of Piezoelectric Ceramic Sheets

[0076] Comparison of contents in parallel Series capacitance value Sensitivity

[0077] C in the table above p C is the value of the parallel capacitor. s Where S is the series capacitance, h is the area of ​​the piezoelectric ceramic sheet 213, and m is the thickness of the piezoelectric ceramic sheet 213. p For parallel sensitivity, M s For series sensitivity, g 33 Let g be the piezoelectric voltage constant along the crystal polarization direction. 31 Let be the piezoelectric voltage constant in the plane perpendicular to the polarization direction.

[0078] Specifically, in this embodiment, the receiving transducer assembly 102 further includes a negative electrode conductive sheet 211 and a positive electrode conductive sheet 214. The negative electrode conductive sheet 211 is attached to the exposed negative electrode side surface of the two stacked piezoelectric ceramic sheets 213, and the positive electrode conductive sheet 214 is attached to the exposed positive electrode side surface of the two stacked piezoelectric ceramic sheets 213.

[0079] The aforementioned negative electrode conductive sheet 211 and positive electrode conductive sheet 214 are used to bring out the corresponding electrodes. The entire stacked structure can be composed of 7 layers, which can be arranged from top to bottom as follows: negative electrode conductive sheet 211, conductive adhesive 212, piezoelectric ceramic sheet 213, conductive adhesive 212, piezoelectric ceramic sheet 213, conductive adhesive 212, and positive electrode conductive sheet 214. The adjacent sheets in the entire stacked structure are bonded together by conductive adhesive 212.

[0080] The piezoelectric ceramic sheet 213 is usually a rectangular sheet of piezoelectric ceramic. The connection between two piezoelectric ceramic sheets 213 is usually made by uniformly bonding them with high-temperature resistant conductive adhesive 212. Both piezoelectric ceramic sheets 213 are polarized in the thickness direction. The thickness direction of the two piezoelectric ceramic sheets 213 is aligned with the polarization direction and they are neatly stacked. The two piezoelectric ceramic sheets 213 are connected by conductive adhesive 212, that is, the negative electrode of one piezoelectric ceramic sheet 213 is bonded to the positive electrode of the other ceramic sheet.

[0081] When bonding ceramics together or between ceramics and electrodes, the conductive adhesive 212 is preferably used to perform a seamless bonding process at a temperature of 230℃ and a pressure of 300kg for up to 24 hours on two piezoelectric ceramic sheets 213. The preferred dimensions of the piezoelectric ceramic sheets 213 are 50.8mm × 25.4mm × 3.6mm. There are two leads: the aforementioned negative electrode conductive sheet 211 and positive electrode conductive sheet 214. The electrode dimensions are typically the same as the ceramic dimensions, with a thickness of approximately 0.05mm. Protruding solder holes are provided at the electrode leads of the negative electrode conductive sheet 211 and the positive electrode conductive sheet 214 for thorough welding of the wires to the solder holes. The negative electrode conductive sheet 211 and the positive electrode conductive sheet 214 are located at the top and bottom of the two ceramic sheets, respectively. Bonding is completed by only three bonding processes between the positive and negative leads and the ceramic sheets. Two piezoelectric ceramic plates 213 are stacked sequentially according to their polarization direction. This simplifies the process and ensures the quality and consistency of the receiving transducer assembly 102. Furthermore, the receiving sensitivity is significantly improved compared to traditional parallel methods. This is due to two factors: firstly, the series connection doubles the sensitivity; secondly, the 1mm increase in piezoelectric ceramic thickness along the polarization direction further enhances the sensitivity by 4dB, resulting in a total sensitivity increase of 10dB, more than three times that of existing parallel technologies. Figure 6 As can be seen from the diagram, the receiving transducer assembly 102 used in this embodiment has a significantly improved sensitivity compared to the traditional parallel connection.

[0082] like Figure 6 As shown, the receiving transducer assembly 102 used in this embodiment has a significantly improved sensitivity compared to the traditional parallel connection. Figure 6 For the sensitivity comparison of series and parallel connections in this embodiment, it can be seen that the sensitivity of the series connection is nearly 3 times higher than that of the parallel connection, approximately 10 dB. The receiving transducer assembly 102 of the above structure is used to receive the acoustic wave signal emitted from the sound source and reflected back by the strata. This assembly is located at the outermost part of the acoustic wave detection and receiving unit 1, with its negative electrode typically exposed at the outer end and the positive electrode inside.

[0083] See Figure 7In this embodiment, the receiving transducer assembly 102 is fixed to the outer periphery of the frame 104 by a fixing sleeve 21, the fixing sleeve 21 being at least partially located between the receiving transducer assembly 102 and the outer periphery of the frame 104. The piezoelectric ceramic sheet 213 in the receiving transducer assembly 102 is used to receive acoustic wave signals and convert acoustic wave pressure and vibration signals into electrical signals, which are then sent to the preamplifier circuit in the receiving preamplifier circuit board assembly 105 for signal filtering, optimization, and amplification. The aforementioned fixing sleeve 21 is embedded with the receiving transducer assembly 102. The lower part of the fixing sleeve 21, located between the receiving transducer assembly 102 and the surface of the frame 104, is an elastic sleeve. On the one hand, it can buffer the downhole pressure on the receiving transducer assembly 102 to protect it. On the other hand, it can ensure the non-free vibration of the receiving transducer assembly 102 to effectively perform acoustic-electric conversion. The upper surface of the receiving transducer assembly 102 is usually exposed, and both ends are embedded in the fixing sleeve 21. The two ends of the fixing sleeve 21 can be fixed with connecting parts such as screws 22 to fix the fixing sleeve 21 to the outer periphery of the frame 104. This prevents the receiving transducer assembly 102 from swinging randomly downhole, which would cause instability in the acoustic wave reception signal, and prevents the reception of noise signals. This ensures that the piezoelectric ceramic sheet 213 performs high-precision and high-stability conversion of acoustic wave signals. This structure is simple and efficient, effectively solving the problem of difficult maintenance caused by adding welding posts to fix the positive and negative electrodes of the piezoelectric ceramic sheet 213. In addition, the use of the fixing sleeve 21 for elastic fixing connection can reduce the pressure of the screw 22 on the receiving transducer assembly 102 to protect the piezoelectric ceramic sheet 213 inside, and can also reduce the torque of the welding posts on the positive and negative electrodes of the piezoelectric ceramic sheet 213 to prevent the positive and negative electrodes from peeling off from the piezoelectric ceramic sheet 213. Furthermore, the fixing sleeve 21 can ensure that the receiving transducer assembly 102 is insulated from the frame 104 to ensure signal accuracy.

[0084] Conventional acoustic wave remote detection receiver units contain only sheet piezoelectric ceramics. In the strata, the converted electrical signal is extremely weak, typically only a few mV. Interference on the transmission cable also reaches a few mV, meaning the interference signal is approximately 100% of the useful signal strength. This is undoubtedly extremely detrimental to acoustic wave signal reception. When these useful and interference signals are fed into subsequent preamplifier and filter circuits, they are synchronously amplified and filtered, but the signal-to-noise ratio remains poor and doesn't change significantly. In this embodiment, the receiving preamplifier circuit board assembly 105 and the receiving transducer assembly 102 are combined in close proximity. On one hand, the useful signal is amplified tenfold, reaching tens of mV. The amplified signal is then transmitted via a transmission cable to the isolated receiving preamplifier circuit board assembly 105. This reduces the interference on the transmission line to only about 10% of the useful signal, improving the signal-to-noise ratio by nearly tenfold.

[0085] See Figure 8 , Figure 8The circuit diagram of the receiving preamplifier circuit board assembly 105 is shown below. Taking the four-component receiving transducer assembly 102 as an example, the receiving preamplifier circuit board assembly 105 in this embodiment includes four identical amplification and filtering circuits. Each receiving transducer assembly 102 is connected to one signal. The signal from the receiving transducer assembly 102 after acoustic-to-electric conversion is first impedance matched. The impedance matching circuit includes R1, R4, R7, and R10. This circuit completes the impedance matching of the receiving transducer assembly 102 to obtain the maximum signal from the receiving transducer assembly 102. After signal matching, signal amplification and filtering are then performed. This circuit is completed by capacitors C1-C4, resistors R2, R3, R5, R6, R8, R9, R11, R12, and amplifier AMP1. The gain of the circuit can be 3, and the bandwidth is usually between 300Hz and 30000Hz.

[0086] in Figure 9 The left image shows the acoustic signal received without a preamplifier circuit board, while the right image shows the acoustic signal received with an active preamplifier circuit board. It can be seen that the signal quality after adding the preamplifier circuit board is greatly improved in signal-to-noise ratio compared with conventional far-field acoustic signals without a preamplifier circuit, which is beneficial for the reception of far-field acoustic reflected wave signals.

[0087] The acoustic wave detection and receiving unit 1 provided in this embodiment uses a pressure chamber 106 to house the receiving preamplifier circuit board assembly 105 and sets up a series receiving preamplifier circuit board assembly 105. This results in high acoustic wave reception sensitivity. The preamplifier circuit is located within the pressure chamber 106 near the receiving preamplifier circuit board assembly 105. This avoids long-distance cable transmission and allows for signal optimization and enhancement through the preamplifier circuit, improving the accuracy and signal-to-noise ratio of the received signal, enhancing signal anti-interference capabilities, and solving the problem of high-precision measurement using long-distance acoustic wave detection in deep earth and deep sea environments. The aforementioned acoustic wave detection and receiving unit 1 can meet the high-sensitivity reception requirements of long-distance acoustic wave logging instruments for deep earth and deep sea acoustic wave logging. It offers advantages such as improved sensitivity and accuracy of acoustic wave reception signals, enhanced temperature and pressure resistance, and improved signal stability and reliability for receiving weak acoustic wave signals in deep earth and deep sea environments.

[0088] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0089] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only 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.

[0090] The acoustic wave long-range detection and receiving system provided by this invention has been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of this invention. The descriptions of the embodiments above are only for the purpose of helping to understand the method and core ideas of this invention. It should be noted that those skilled in the art can make several improvements and modifications to this invention without departing from the principles of this invention, and these improvements and modifications also fall within the protection scope of the claims of this invention.

Claims

1. A sound wave long-range detection and receiving system, characterized in that, It includes at least two acoustic wave detection and receiving units and a soundproof cover located between two adjacent acoustic wave detection and receiving units; the adjacent acoustic wave detection and receiving units are fixedly connected by the soundproof cover, and the soundproof cover forms an acoustic isolation cavity between the adjacent acoustic wave detection and receiving units. The acoustic wave detection and receiving unit includes a columnar frame with a pressure chamber inside; a plurality of receiving transducer assemblies are evenly distributed along the circumferential direction on the outer periphery of the frame, and a receiving preamplifier circuit board assembly is disposed inside the pressure chamber. The receiving transducer assemblies are electrically connected to the receiving preamplifier circuit board assembly.

2. The acoustic wave long-range detection and receiving system according to claim 1, characterized in that, The pressure chamber has an opening at one end and a bottom at the other end along the axial direction of the frame; The receiving preamplifier circuit board assembly includes a preamplifier circuit board and a pressure-bearing block welded to the preamplifier circuit board, wherein the pressure-bearing block is sealed to the opening of the pressure-bearing chamber.

3. The acoustic wave long-range detection and receiving system according to claim 2, characterized in that, The pressure-bearing block is provided with a connector that penetrates the pressure-bearing block along the axial direction. The end of the connector near the preamplifier circuit board is soldered to the gold finger of the preamplifier circuit board, and the end of the connector away from the preamplifier circuit board protrudes from the surface of the pressure-bearing block.

4. The acoustic wave long-range detection and receiving system according to claim 3, characterized in that, It also includes a socket located on the side of the pressure block away from the front circuit board, wherein the female connector in the socket is connected to the corresponding connector; The socket has a tie post extending along the axial direction on the surface away from the pressure block.

5. The acoustic wave long-range detection and receiving system according to claim 1, characterized in that, It also includes a housing and high-temperature oil located inside the housing; the acoustic wave detection and receiving unit and the soundproof cover are located inside the housing and are immersed in the high-temperature oil.

6. The acoustic wave long-range detection and receiving system according to claim 5, characterized in that, The outer casing is provided with a reinforcing grid corresponding to the position of the receiving transducer assembly.

7. The acoustic wave long-range detection and receiving system according to claim 5, characterized in that, The outer casing surface is provided with a gapper, the top of which protrudes from the outer casing surface.

8. The acoustic wave long-range detection and receiving system according to claim 7, characterized in that, The surface of the gap is provided with sound-absorbing holes.

9. The acoustic wave remote detection receiving system according to any one of claims 1 to 8, characterized in that, The receiving transducer assembly includes two piezoelectric ceramic sheets stacked together, wherein the piezoelectric ceramic sheets are polarized along the thickness direction; The positive electrode side surface of one piezoelectric ceramic sheet is in contact with and electrically connected to the negative electrode side surface of another piezoelectric ceramic sheet, so that the two piezoelectric ceramic sheets are connected in series.

10. The acoustic wave long-range detection and receiving system according to claim 9, characterized in that, The receiving transducer assembly further includes a negative electrode conductive sheet and a positive electrode conductive sheet. The negative electrode conductive sheet is attached to the exposed negative electrode side surface of the two stacked piezoelectric ceramic sheets, and the positive electrode conductive sheet is attached to the exposed positive electrode side surface of the two stacked piezoelectric ceramic sheets.

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