A sonic receiver while drilling and its manufacturing method and using method

Abstract

This invention proposes a logging-while-drilling (LWD) acoustic receiver, its manufacturing method, and its usage method, comprising: a drill collar skeleton, the drill collar skeleton being a hollow cylindrical structure with a water inlet in its center; an arc-shaped frame support, the arc-shaped frame support being evenly arranged circumferentially on the sidewalls of the drill collar skeleton, and receiving transducers being disposed on the arc-shaped frame support, the receiving transducers being evenly arranged circumferentially on the drill collar skeleton; wherein, a watertight insulating prestressed layer is provided on the outer surface of the arc-shaped frame support, which seals and fixes the receiving transducers.

Description

Technical Field

[0001] This invention relates to a logging-while-drilling acoustic receiver and its manufacturing and usage methods, belonging to the field of petroleum imaging logging technology. Background Technology

[0002] Sonic logging while drilling (SLVM) technology has been widely applied in oil and gas exploration and development, becoming an indispensable technical means for oil and gas drilling operations, geological steering, formation evaluation, and reservoir characterization. SLVM offers significant advantages in improving drilling efficiency, reducing rig downtime, lowering operating costs, and enhancing the quality of real-time formation evaluation. Compared to wireline logging instruments, SLVM operates in a harsher environment, inevitably affected by drill string vibration, drilling fluid erosion, and drilling noise. Therefore, the design and development of SLVM instruments face more complex technical challenges, and one of the urgent technical problems to be solved is the technology for receiving downhole acoustic signals in harsh environments.

[0003] Downhole acoustic signal reception is achieved using a logging-while-drilling (WSD) acoustic receiver directly mounted on the drill collar structure. A high-sensitivity broadband receiver can significantly improve detection capabilities and measurement signal-to-noise ratio. Currently, domestic and international WWD acoustic receivers generally employ two structural designs: ring-shaped and strip-shaped. The ring-shaped structure uses non-conductive materials such as epoxy resin or rubber to encapsulate multiple circumferentially distributed piezoelectric ceramic sheets. Due to the low precision of the encapsulation process, the multiple circumferentially distributed piezoelectric ceramic sheets exhibit a non-uniform distribution, resulting in poor directional reception. The strip-shaped structure uses a long strip of metal tube to encapsulate multiple axially distributed piezoelectric ceramic sheets using an oil-filled pressure-balanced encapsulation. Because the metal tube encapsulation reduces the amplitude of the received signal and introduces clutter interference, it also results in a low measurement signal-to-noise ratio. Furthermore, the complexity of the pressure-balanced structure makes on-site maintenance difficult. Therefore, developing a WWD acoustic receiver with accurate directional orientation and high sensitivity is particularly important, as it directly determines whether the WWD acoustic logging instrument can acquire effective formation acoustic signals.

[0004] With the large-scale exploration and development of unconventional oil and gas resources such as shale gas, shale oil, tight gas, and tight oil in China, the importance of logging-while-drilling (LWD) technology is becoming increasingly apparent. However, existing LWD receivers have significant limitations, failing to identify the directional heterogeneity of unconventional reservoirs. Furthermore, due to low electromechanical coupling efficiency and low receiver sensitivity, they also cannot detect distant formation interfaces and fractures outside the well. Summary of the Invention

[0005] To address the aforementioned technical problems in existing technologies, this invention proposes a logging-while-drilling (LWD) acoustic receiver, which overcomes the shortcomings of existing LWD acoustic receivers such as poor azimuth accuracy and low receiving sensitivity. It also solves problems such as low measurement azimuth resolution, small received signal amplitude, large clutter interference, and low signal-to-noise ratio of existing LWD acoustic logging instruments, thereby improving the ability of LWD acoustic logging instruments to identify azimuth and conduct long-distance detection in unconventional reservoirs.

[0006] According to one aspect of the present invention, a logging-while-drilling (LWD) receiver is provided, comprising:

[0007] The drill collar frame is a hollow cylindrical structure with a water inlet in the middle.

[0008] An arc-shaped frame support is provided, which is evenly arranged circumferentially on the side wall of the drill collar skeleton. A receiving transducer is provided on the arc-shaped frame support, which is evenly arranged circumferentially on the drill collar skeleton.

[0009] The outer surface of the arc-shaped frame support is provided with a watertight insulating prestressed layer, which seals and fixes the receiving transducer.

[0010] A further improvement of the present invention is that there are four arc-shaped frame support frames, which are evenly arranged at 90 degrees around the circumference of the drill collar skeleton.

[0011] Two receiving transducers are installed on each arc-shaped frame support, and the receiving transducers are evenly arranged at 45 degrees around the circumference of the drill collar skeleton.

[0012] A further improvement of the present invention is that an elastic vibration isolation layer is provided on the outer surface of the watertight insulating prestressed layer.

[0013] A further improvement of the present invention is that the arc-shaped frame support is made of PEEK polymer material, and the circumferential angle of the arc-shaped frame support is 80° to 84°.

[0014] The arc-shaped frame support is provided with a groove for installing the receiving transducer, and a pressure-bearing sealing joint for connecting the positive electrode lead and the negative electrode lead is provided at the top of the groove.

[0015] A further improvement of the present invention is that the groove is a rectangular groove and the receiving transducer is a rectangular receiving transducer;

[0016] The rectangular receiving transducer includes a double-laminated rectangular piezoelectric vibrator. The outer surface of the double-laminated rectangular piezoelectric vibrator is plated with a silver layer to lead out a positive electrode lead, and the inner surface is plated with a silver layer to lead out a negative electrode lead.

[0017] A further improvement of the present invention is that the groove is a cylindrical groove and the receiving transducer is a cylindrical receiving transducer.

[0018] The cylindrical receiving transducer includes a cylindrical piezoelectric vibrator, with a positive electrode lead extending from the outer surface of the cylindrical piezoelectric vibrator and a negative electrode lead extending from the inner surface of the piezoelectric vibrator.

[0019] A further improvement of the present invention is that the drill collar frame is made of P550 cemented carbide steel.

[0020] A further improvement of the present invention is that the watertight insulating prestressed layer is an epoxy resin sealant layer, and the elastic vibration isolation layer is a high-temperature fluororubber.

[0021] A further improvement of the present invention is that the piezoelectric vibrator of the receiving transducer is made of a modified high-temperature resistant lead niobate piezoelectric ceramic material.

[0022] According to a second aspect of the present invention, a method for manufacturing a logging-while-drilling (LWD) receiver is also provided, comprising:

[0023] Step 1: Replace Pb in lead metaniobate with a substitute element for doping. 2+ A modified high-temperature resistant lead niobate piezoelectric ceramic material was prepared, and piezoelectric oscillators were fabricated by processing and bonding the modified high-temperature resistant lead niobate piezoelectric ceramic material. The piezoelectric oscillators were subjected to high-temperature oil bath aging, screening and pairing, and several piezoelectric oscillators with the same or similar impedance characteristics were selected.

[0024] Step 2: Fabricate the drill collar skeleton and the arc-shaped frame support; clean the piezoelectric vibrator, arc-shaped frame support, drill collar skeleton and other parts, remove oil stains, and dry them at high temperature;

[0025] Step 3: Install the piezoelectric vibrator in the groove of the arc-shaped frame to form a receiving transducer, and weld the positive and negative electrode leads to the pressure-bearing sealing joint; then install and fix the arc-shaped frame on the drill collar skeleton;

[0026] Step 4: Seal the inner and outer surfaces of the arc-shaped frame support with a watertight insulating prestressed layer, and then cast a vulcanized elastic vibration isolation layer on the inner and outer surfaces of the watertight insulating prestressed layer.

[0027] According to a third aspect of the invention, a method of using a logging-while-drilling (LWD) receiver is also proposed, comprising: combining eight receiver transducers distributed circumferentially into a monopole receiver mode, an off-pole azimuth receiver mode, a dipole receiver mode, a quadrupole receiver mode, and an octupole receiver mode.

[0028] Compared with the prior art, the advantages of the present invention are as follows:

[0029] The sonic logging receiver described in this invention overcomes the shortcomings of existing sonic logging receivers, such as poor azimuth accuracy and low receiving sensitivity. It also solves the problems of low azimuth resolution, small received signal amplitude, large clutter interference, and low signal-to-noise ratio of existing sonic logging instruments, thereby improving the ability of sonic logging instruments to identify azimuth in unconventional reservoirs and to detect them over long distances.

[0030] The sonic logging receiver described in this invention employs a circular array structure, providing excellent azimuth orientation characteristics. Furthermore, the fabrication method for the sonic logging receiver is based on a modified high-temperature resistant lead metaniobate piezoelectric ceramic material, exhibiting high receiving sensitivity. Similar to logging-while-drilling instruments, the sonic logging receiver is installed within a non-magnetic drill collar, and it substantially does not affect the strength or voltage stabilization function of the non-magnetic drill collar. Attached Figure Description

[0031] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, in which:

[0032] Figure 1 The diagram shown is a structural schematic of a logging-while-drilling (LWD) receiver according to an embodiment of the present invention.

[0033] Figure 2 The diagram shown is a structural schematic of a rectangular receiving transducer according to an embodiment of the present invention.

[0034] Figure 3 The diagram shown is a schematic representation of a cylindrical receiving transducer according to an embodiment of the present invention.

[0035] Figure 4 The diagram shown is a schematic diagram of the monopole receiving mode of a receiving transducer according to an embodiment of the present invention;

[0036] Figure 5 The diagram shown is a schematic diagram of the polarizer orientation receiving mode of a receiving transducer according to an embodiment of the present invention.

[0037] Figure 6 The diagram shown is a schematic diagram of the X-direction dipole receiving mode of a receiving transducer according to an embodiment of the present invention;

[0038] Figure 7 The diagram shown is a schematic diagram of the Y-direction dipole receiving mode of a receiving transducer according to an embodiment of the present invention;

[0039] Figure 8 The diagram shown is a schematic diagram of the octet receiving mode of a receiving transducer according to an embodiment of the present invention;

[0040] Figure 9 The diagram shown is a schematic diagram of the quadrupole receiving mode of a receiving transducer according to an embodiment of the present invention;

[0041] The accompanying drawings are not drawn to scale.

[0042] The meanings of the reference numerals in the attached figures are as follows:

[0043] 1. Drill collar frame; 2. Arc-shaped frame support; 3. Receiving transducer; 4. Watertight insulating prestressed layer; 5. Elastic vibration isolation layer; 6. Pressure-bearing sealing joint; 11. Water eye; 31. Rectangular receiving transducer; 311. Positive electrode lead; 312. Negative electrode lead; 32. Cylindrical groove; 321. Positive electrode lead; 322. Negative electrode lead. Detailed Implementation

[0044] To make the technical solutions and advantages of the present invention clearer, exemplary embodiments of the present invention will be described in further detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not an exhaustive list of all embodiments. Furthermore, without conflict, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0045] Currently, sonic logging while drilling (SWP) technology has been widely applied in oil and gas exploration and development, becoming an indispensable technical means for oil and gas drilling operations, geological steering, formation evaluation, and reservoir characterization. SWP offers significant advantages in improving drilling efficiency, reducing rig downtime, lowering operating costs, and enhancing the quality of real-time formation evaluation. Compared to wireline logging instruments, SWP instruments operate in harsher environments, inevitably affected by drill string vibration, drilling fluid erosion, and drilling noise. Therefore, the design and development of SWP instruments face more complex technical challenges, and one of the urgent technical problems to be solved is the technology for receiving downhole acoustic signals in harsh environments.

[0046] Downhole acoustic signal reception is achieved using a logging-while-drilling (WSD) acoustic receiver directly mounted on the drill collar structure. A high-sensitivity broadband receiver can significantly improve detection capabilities and measurement signal-to-noise ratio. Currently, domestic and international WWD acoustic receivers generally employ two structural designs: ring-shaped and strip-shaped. The ring-shaped structure uses non-conductive materials such as epoxy resin or rubber to encapsulate multiple circumferentially distributed piezoelectric ceramic sheets. Due to the low precision of the encapsulation process, the multiple circumferentially distributed piezoelectric ceramic sheets exhibit a non-uniform distribution, resulting in poor directional reception. The strip-shaped structure uses a long strip of metal tube to encapsulate multiple axially distributed piezoelectric ceramic sheets using an oil-filled pressure-balanced encapsulation. Because the metal tube encapsulation reduces the amplitude of the received signal and introduces clutter interference, it also results in a low measurement signal-to-noise ratio. Furthermore, the complexity of the pressure-balanced structure makes on-site maintenance difficult. Therefore, developing a WWD acoustic receiver with accurate directional orientation and high sensitivity is particularly important, as it directly determines whether the WWD acoustic logging instrument can acquire effective formation acoustic signals.

[0047] To overcome the shortcomings of existing technologies, such as poor azimuth accuracy and low receiving sensitivity, this invention provides a logging-while-drilling (LWD) acoustic receiver suitable for receiving a full spectrum of acoustic waveforms, including sliding P-waves, sliding S-waves, pseudo Rayleigh waves, Stoneley waves, bending waves, and reflected waves, under LWD conditions. On one hand, the provided LWD acoustic receiver employs a circular array structure with excellent azimuth orientation characteristics; on the other hand, the provided LWD acoustic receiver fabrication method is based on a modified high-temperature resistant lead metaniobate piezoelectric ceramic material, which exhibits high receiving sensitivity. Similar to LWD instruments, the LWD acoustic receiver is installed in a non-magnetic drill collar and has minimal impact on the strength and pressure stabilization function of the non-magnetic drill collar.

[0048] In such Figure 1 In the illustrated embodiment, the logging-while-drilling acoustic receiver includes:

[0049] Drill collar frame 1, wherein the drill collar frame 1 is a hollow cylindrical structure, and a water eye 11 is provided in the middle part;

[0050] An arc-shaped frame support frame 2 is evenly arranged circumferentially on the side wall of the drill collar skeleton 1, and the arc-shaped frame support frame is provided with several grooves.

[0051] The receiving transducer 3 is disposed in the groove and is used to receive the full wave train waveforms of sound waves, including gliding longitudinal waves, gliding transverse waves, pseudo Rayleigh waves, Stoneley waves, bending waves, and reflected waves.

[0052] The inner and outer surfaces of the arc-shaped frame support 2 are respectively provided with watertight insulating prestressed layers 4; preferably, the outer surface of the watertight insulating prestressed layer 4 is provided with an elastic vibration isolation layer 5.

[0053] In this embodiment, the receiving transducer 3 is uniformly arranged circumferentially, overcoming the shortcomings of existing sonic logging receivers such as poor azimuth accuracy and low receiving sensitivity. Furthermore, the inclusion of a watertight insulating prestressed layer 4 and an elastic vibration isolation layer 5, along with the absence of metal components, solves problems such as low azimuth resolution, small received signal amplitude, high clutter interference, and low signal-to-noise ratio in existing sonic logging instruments, thus improving the instrument's ability to perform azimuth identification and long-distance detection in unconventional reservoirs.

[0054] In a preferred embodiment, there are four arc-shaped frame support frames 2, which are evenly arranged at 90 degrees around the drill collar skeleton 1. Each arc-shaped frame support frame 2 is equipped with two receiving transducers 3, which are evenly arranged at 45 degrees around the drill collar skeleton 1.

[0055] In the logging-while-drilling receiver according to this embodiment, the receiving transducers 3 are evenly arranged at 45 degrees around the drill collar frame 1 to form eight receiving transducers 3. During operation, different modes can be combined according to the received signal, such as monopole receiving mode, off-pole azimuth receiving mode, dipole receiving mode, quadrupole receiving mode and octupole receiving mode.

[0056] In one embodiment, the arc-shaped frame support 2 is made of PEEK polymer material, and the circumferential angle of the arc-shaped frame support 2 is 80° to 84°.

[0057] The arc-shaped frame support 2 is provided with a groove for mounting the receiving transducer 3.

[0058] Preferably, the circumferential angle of the arc-shaped frame support 2 is 80° to 84°, and the height is 54 to 56 mm. The groove on the arc-shaped frame support 2 is cuboid or cylindrical.

[0059] In a preferred embodiment, the groove is a rectangular groove, and the receiving transducer 3 is a rectangular receiving transducer 31;

[0060] The rectangular receiving transducer 31 includes a double-laminated rectangular piezoelectric vibrator. The outer surface of the double-laminated rectangular piezoelectric vibrator is plated with a silver layer to lead out a positive electrode lead 311, and the inner surface is plated with a silver layer to lead out a negative electrode lead 312.

[0061] The grooves of the receiving transducers 3 and rectangular receiving transducers 31 correspond one-to-one, and each receiving transducer 3 is tightly embedded in its corresponding groove. A pressure-bearing sealing joint 6 is also provided at the top of the groove for connecting the positive electrode lead and the negative electrode lead. The length of the double-laminated rectangular piezoelectric vibrator is 50–52 mm, the width is 19–22 mm, and the thickness is 5–6 mm. The operating frequency of the receiving transducers 3 is 0.5 Hz–40 kHz, with a receiving sensitivity of -200 dB, a receiving response fluctuation of less than 3 dB, and an azimuth resolution better than 22.5°.

[0062] In another preferred embodiment, the groove is a cylindrical groove, and the receiving transducer 3 is a cylindrical receiving transducer 32;

[0063] The cylindrical receiving transducer 32 includes a cylindrical piezoelectric vibrator. The outer surface of the cylindrical piezoelectric vibrator is plated with a silver layer to lead out a positive electrode lead 321, and the inner surface is plated with a silver layer to lead out a negative electrode lead 322.

[0064] The grooves of the receiving transducers 3 and cylindrical receiving transducers 32 correspond one-to-one, and each receiving transducer 3 is tightly embedded in its corresponding groove. A pressure-bearing sealing joint 6 is also provided at the top of the groove for connecting the positive electrode lead and the negative electrode lead. The outer diameter of the cylindrical piezoelectric vibrator 32 is 4–6 mm, the thickness is 1–2 mm, and the height is 50–52 mm. Similar to the rectangular receiving transducers 3, the cylindrical receiving transducers 3 also operate at frequencies from 0.5 Hz to 40 kHz, with a receiving sensitivity of -200 dB, a receiving response fluctuation of less than 3 dB, and an azimuth resolution better than 22.5°.

[0065] In one embodiment, the drill collar frame 1 has a hollow cylindrical structure with a through-hole 11 in its center, serving as a channel for drilling fluid flow. An arc-shaped frame support 2 is mounted on the outer wall of the drill collar frame 1. In this embodiment, the drill collar frame 1 is made of P550 hard alloy steel. Preferably, the outer diameter of the drill collar frame 1 is φ160–164 mm, the height is 58–62 mm, and the diameter of the through-hole 11 is φ50 mm.

[0066] In one embodiment, the inner and outer surfaces of the arc-shaped frame support frame 2 are wrapped with a layer of epoxy resin sealant, and the receiving transducer 3 embedded in the arc-shaped frame support frame 2 is insulated, sealed and pressure resistant, forming a watertight insulating prestressed layer 4 with waterproof and pressure resistant functions.

[0067] The inner and outer surfaces of the watertight insulating prestressed layer 4 are further coated with high-temperature fluororubber through casting and vulcanization, completely enclosing the arc-shaped frame support 2, the receiving transducer 3, and the watertight insulating prestressed layer 4. This decouples and eliminates the influence of the drill collar skeleton 1 vibration, forming an elastic vibration isolation layer 5 with decoupling and vibration reduction functions, thus enhancing the vibration resistance of the receiving transducer 3. The thickness of the watertight insulating prestressed layer 4 is 2–3 mm, and the thickness of the elastic vibration isolation layer 5 is 2.5–3.5 mm.

[0068] According to a second aspect of the present invention, a method for manufacturing a logging-while-drilling (LWD) receiver is also provided, the method comprising the following steps:

[0069] Step 1: Replace Pb in lead metaniobate with alternative elements (such as Sr2+, Ba2+, Ca2+, etc.). 2+ A modified high-temperature resistant lead niobate piezoelectric ceramic material was prepared, and piezoelectric oscillators were fabricated by bonding the modified high-temperature resistant lead niobate piezoelectric ceramic material. The piezoelectric oscillators were subjected to high-temperature oil bath aging, screening and pairing, and several piezoelectric oscillators with the same or similar impedance characteristics were selected.

[0070] Step 2: Fabricate drill collar skeleton 1 and arc-shaped frame support frame 2; clean the piezoelectric vibrator, arc-shaped frame support frame 2, drill collar skeleton 1 and other parts, remove oil stains, and dry them at high temperature.

[0071] Step 3: Install the piezoelectric vibrator in the groove of the arc-shaped frame support frame 2 to form the receiving transducer 3, and weld the positive and negative electrode leads to the pressure-bearing sealing joint 6; then install and fix the arc-shaped frame support frame 2 on the drill collar skeleton 1.

[0072] Step 4: Seal the inner and outer surfaces of the arc-shaped frame support 2 with a watertight insulating prestressed layer 4, and cast a vulcanized elastic vibration isolation layer 5 on the inner and outer surfaces of the watertight insulating prestressed layer 4.

[0073] The above method can be used to manufacture the sonic logging receiver used in drilling.

[0074] This invention is based on a modified high-temperature resistant lead niobate piezoelectric ceramic material and uses a circular array structure, which has high receiving sensitivity and good orientation characteristics.

[0075] In one specific embodiment, the method includes the following steps:

[0076] A modified high-temperature resistant lead niobate piezoelectric ceramic material was prepared by doping lead niobate with elements such as Sr2+, Ba2+, and Ca2+ to replace Pb2+. The modified high-temperature resistant lead niobate piezoelectric ceramic was then used to process and bond the materials to create a piezoelectric oscillator.

[0077] The piezoelectric vibrators are subjected to high-temperature oil bath aging, screening, and pairing, and eight or more piezoelectric vibrators with the same or similar impedance characteristics are selected.

[0078] The drill collar skeleton 1 is made of P550 hard alloy steel, and the arc-shaped frame support frame 2 is made of PEEK polymer material, with grooves made therein.

[0079] Clean the piezoelectric vibrator, arc-shaped frame support 2, drill collar skeleton 1 and other parts, remove oil stains, and dry at high temperature.

[0080] Two piezoelectric vibrators with similar performance are embedded in each arc-shaped frame support 2, and the positive and negative electrode leads are welded to the pressure-bearing sealing joint 6. Then, the four arc-shaped frame support 2 are installed and fixed on the drill collar skeleton 1.

[0081] A layer of epoxy resin sealant is pressurized and sealed on the inner and outer surfaces of the arc-shaped frame support 2 to form a watertight insulating prestressed layer 4.

[0082] A layer of high-temperature fluororubber is cast and vulcanized on the inner and outer surfaces of the watertight insulating prestressed layer 4 to form an elastic vibration isolation layer 5. The high-temperature wire of the pressure-bearing sealing joint 6 is led out to the outermost side of the elastic vibration isolation layer 5 to form a drilling acoustic logging receiver.

[0083] According to a third aspect of the present invention, a method for using a logging-while-drilling acoustic receiver is also provided, comprising: eight receiving transducers 3 distributed circumferentially to form a monopole receiving mode, an off-pole azimuth receiving mode, a dipole receiving mode, a quadrupole receiving mode, and an octupole receiving mode.

[0084] The specific plan is as follows:

[0085] Monopole receiver mode, such as Figure 4 As shown, the eight receiving transducers 3 synchronously receive the acoustic wave signal, and all the signals are directly added together.

[0086] Polarizer azimuth receiving mode, such as Figure 5 As shown, the eight receiving transducers 3 receive acoustic signals independently in a sequential cycle.

[0087] Dipole receiver mode, such as Figure 6 and Figure 7 As shown, two receiving transducers 3 located in the x or y direction synchronously receive acoustic signals, and the two acoustic signals are subtracted and combined to form a dipole receiving mode in the x or y direction.

[0088] Quadrupole receiver mode, such as Figure 9The two receiving transducers 3 located in the x-direction and the two receiving transducers 3 located in the y-direction synchronously receive the acoustic wave signal. Then, the two acoustic wave signals in the x-direction are added together and the two acoustic wave signals in the y-direction are added together. The two pairs of added acoustic wave signals are then subtracted to form a quadrupole receiving mode.

[0089] Octagonal receiving mode, such as Figure 8 As shown, the eight receiving transducers 3 synchronously receive acoustic signals and can be combined into an octet receiving mode by adding adjacent array elements in opposite phase.

[0090] This invention is applied to the development of logging-while-drilling (LWD) instruments, and has significant advantages in azimuth orientation identification and long-distance detection. It is suitable for evaluating the circumferential heterogeneity of unconventional oil and gas reservoirs and identifying geological anomalies such as long-distance off-well interfaces and fractures.

[0091] It should be understood that the embodiments disclosed herein are not limited to the specific structures, processing steps, or materials disclosed herein, but should be extended to equivalent substitutions of these features as understood by those skilled in the art. It should also be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0092] In the description of this invention, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0093] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0094] Certain terms are used throughout this application to refer to specific system components. As those skilled in the art will recognize, the same components may often be referred to by different names, and therefore this application is not intended to distinguish components that differ only in name and not in function. The terms "an embodiment" or "embodiment" used in the specification mean that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. Therefore, the phrase "an embodiment" or "embodiment" appearing throughout the specification does not necessarily refer to the same embodiment.

[0095] The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the invention to the forms disclosed. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described in order to better illustrate the principles and practical application of the invention, and to enable those skilled in the art to understand the invention and to design various embodiments with various modifications suitable for a particular purpose.

[0096] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and / or modifications falling within the scope of the invention, and all changes and / or modifications made according to embodiments of the invention should be covered within the protection scope of the invention.

Claims

1. A method for manufacturing a logging-while-drilling (LWD) acoustic receiver, characterized in that, include: Step 1: A modified high-temperature resistant lead niobate piezoelectric ceramic material is prepared by replacing Pb2+ in lead niobate with alternative elements. The modified high-temperature resistant lead niobate piezoelectric ceramic is then used to process and bond piezoelectric oscillators. The piezoelectric oscillators are subjected to high-temperature oil bath aging, screening, and pairing to select several piezoelectric oscillators with the same or similar impedance characteristics. Step 2: Make the drill collar skeleton (1) and the arc-shaped frame support frame (2); clean the piezoelectric vibrator, the arc-shaped frame support frame (2), and the drill collar skeleton (1), remove oil stains, and dry them at high temperature; Step 3: Install the piezoelectric vibrator in the groove of the arc-shaped frame support frame (2) to form a receiving transducer (3), and weld the positive and negative electrode leads to the pressure-bearing sealing joint (6); then install and fix the arc-shaped frame support frame (2) on the drill collar skeleton (1); Step 4: Fill the inner and outer surfaces of the arc-shaped frame support frame (2) with a watertight insulating prestressed layer (4), and pour a vulcanized elastic vibration isolation layer (5) on the inner and outer surfaces of the watertight insulating prestressed layer (4). The logging-while-drilling acoustic receiver includes: Drill collar skeleton (1), the drill collar skeleton (1) is a hollow cylindrical structure with a water eye (11) in the middle. An arc-shaped frame support (2) is evenly arranged on the side wall of the drill collar skeleton (1) along the circumference. A receiving transducer (3) is provided on the arc-shaped frame support. The receiving transducer (3) is evenly arranged in the circumference of the drill collar skeleton (1). The outer surface of the arc-shaped frame support frame (2) is provided with a watertight insulating prestressed layer (4), which seals and fixes the receiving transducer (3). The arc-shaped frame support frame (2) consists of four parts, which are evenly arranged at 90 degrees around the drill collar skeleton (1). Two receiving transducers (3) are provided on each arc-shaped frame support frame (2), and the receiving transducers (3) are evenly arranged at 45 degrees in the circumferential direction of the drill collar skeleton (1). The arc-shaped frame support (2) is made of PEEK polymer material, and the circumferential angle of the arc-shaped frame support (2) is 80° to 84°. The arc-shaped frame support frame (2) is provided with a groove for installing the receiving transducer (3), and the top of the groove is provided with a pressure-bearing sealing joint (6) for connecting the positive electrode lead and the negative electrode lead. The groove is a rectangular groove, and the receiving transducer (3) is a rectangular receiving transducer (31). The rectangular receiving transducer (31) includes a double-laminated rectangular piezoelectric vibrator. The outer surface of the double-laminated rectangular piezoelectric vibrator is plated with a silver layer to lead out a positive electrode lead (311), and the inner surface is plated with a silver layer to lead out a negative electrode lead (312). An elastic vibration isolation layer (5) is provided on the outer surface of the watertight insulating prestressed layer (4); The drill collar frame (1) is made of P550 hard alloy steel.

2. The method for manufacturing a logging-while-drilling (LWD) acoustic receiver according to claim 1, characterized in that, The watertight insulating prestressed layer (4) is an epoxy resin sealant layer, and the elastic vibration isolation layer (5) is a high-temperature fluororubber.

3. The method for manufacturing a logging-while-drilling (LWD) acoustic receiver according to claim 2, characterized in that, The piezoelectric vibrator of the receiving transducer (3) is made of a modified high-temperature resistant lead niobate piezoelectric ceramic material.

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