Cable measurement type digital acoustic logging instrument

Abstract

The utility model discloses a cable measurement type digital acoustic logging instrument which comprises a circuit short section and an acoustic system short section which are arranged in series, and an internal circuit of the circuit short section is electrically connected with an internal circuit of the acoustic system short section through a pressure-bearing connector. The circuit short section comprises a first shell, and an integrated circuit module is arranged in the first shell; the acoustic system short section comprises a second shell, a metal rod is arranged in the second shell, and a transmitting crystal, a transmitting transformer and a receiving crystal are arranged on the metal rod; the outer side of the metal rod is sleeved with a layer of sound insulation structure; metal bins are arranged on the circumferential outer sides of each transmitting crystal, each transmitting transformer and each receiving crystal, and the metal bins are filled with silicone oil. According to the cable measurement type digital acoustic logging instrument, a leather bag in a traditional logging instrument is replaced with the metal bin, and the phenomena that the leather bag is prone to aging and oil leakage and the leather bag is seriously corroded are avoided; in addition, the through line, the transmitting line and the receiving line are separately arranged inside and outside the metal rod, so that the shielding interference problem between lines is effectively improved.

Description

A cable-mounted digital acoustic logging tool Technical Field

[0001] This utility model relates to the field of logging instrument technology, and in particular to a cable-mounted digital acoustic logging instrument. Background Technology

[0002] Digital acoustic logging tools are advanced downhole measurement tools capable of performing acoustic logging at varying source-to-sink distances and intervals. They measure the acoustic transmission time of a segment of formation around the wellbore from transmitter to receiver. The measurement results are used to calculate formation porosity or directly for formation correlation. They can also be used to record the entire acoustic signal, extracting more information, including the amplitude and velocity of P-waves and S-waves. In short, digital acoustic logging tools are widely used in time-difference logging, cementing quality assessment, and confirmation of fractured formations, making them one of the most important logging devices in oil and gas exploration.

[0003] Existing traditional logging tools generally use a bladder structure, which is prone to aging and oil leakage. Hydrogen sulfide also causes severe corrosion to the bladder, resulting in a short service life. In addition, there is significant interference between internal structural components of the instrument. Summary of the Invention

[0004] In view of the above-mentioned defects or deficiencies in the prior art, it is desirable to provide a cable-mounted digital acoustic logging tool.

[0005] This utility model provides a cable-mounted digital acoustic logging tool, comprising a circuit sub-section and an acoustic sub-section arranged in series. The internal wiring of the circuit sub-section and the internal wiring of the acoustic sub-section are electrically connected through a pressure-bearing connector. The circuit sub-section includes a first outer shell, inside which an integrated circuit module is fixedly disposed. The acoustic sub-section includes a second outer shell, inside which a metal rod is fixedly disposed along its height. Two transmitting crystals, two transmitting transformers, and four receiving crystals are fixedly disposed on the metal rod. A sound insulation structure is fixedly sleeved on the circumferential outer side of the metal rod. A metal chamber is fixedly disposed on the circumferential outer side of each transmitting crystal, transmitting transformer, and receiving crystal, and the interior of the metal chamber is filled with silicone oil.

[0006] Furthermore, the interior of the metal rod is hollow along its axial direction, and all 18 through lines are installed inside the metal rod.

[0007] Furthermore, the sound insulation structure is made of composite material, and a groove is formed on the sound insulation structure along the height direction of the metal rod. The receiving crystal, the transmitting transformer, and the circuit of the receiving crystal are all fixedly installed inside the groove.

[0008] Furthermore, the composite material is made of low-velocity rubber.

[0009] Furthermore, one end of the first housing is threadedly connected to one end of the second housing.

[0010] Furthermore, the two emitting crystals are arranged sequentially from top to bottom on the metal rod, namely the first emitting crystal and the second emitting crystal; the distance between the first emitting crystal and the second emitting crystal is set to 2 feet.

[0011] Furthermore, the two transmitting transformers are fixedly mounted on the metal rod between the first transmitting crystal and the second transmitting crystal.

[0012] Furthermore, the four receiving crystals are arranged sequentially from top to bottom on the metal rod below the second transmitting crystal, namely the first receiving crystal, the second receiving crystal, the third receiving crystal, and the fourth receiving crystal; the spacing between two adjacent receiving crystals is set to 0.5 feet.

[0013] Furthermore, the distance between the second transmitting crystal and the first receiving crystal is set to 3 feet.

[0014] Furthermore, the metal compartment is made of stainless steel.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] This utility model of a cable-mounted digital acoustic logging tool adopts a bladder-free structure. By replacing the bladder in traditional logging tools with a metal chamber, it effectively solves the problems of bladder aging and oil leakage, as well as severe corrosion by hydrogen sulfide, thus improving the product's service life. In addition, a hollow metal rod is set inside the second shell of the acoustic subsection. The transmitting line of the transmitting crystal, the receiving line of the receiving crystal, and the transmitting transformer line are routed on the outside of the metal rod, while 18 through lines are routed inside the metal rod, i.e., the lines are routed separately, effectively improving the shielding interference problem between the lines. Furthermore, the transmitting crystal, transmitting transformer, and receiving crystal on the metal rod are connected by a low-velocity rubber material, further blocking the mechanical transmission path.

[0017] It should be understood that the content described in the utility model description section is not intended to limit the key or important features of the embodiments of this utility model, nor is it intended to limit the scope of this utility model.

[0018] Other features of this invention will become readily apparent from the following description. Attached Figure Description

[0019] Other features, objects, and advantages of this invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings:

[0020] Figure 1 is a structural schematic diagram of a cable-mounted digital acoustic logging tool provided in an embodiment of this utility model;

[0021] Figure 2 is a block diagram of the overall circuit structure of the logging tool;

[0022] Figure 3 is a schematic diagram of the receiving board of the main control processing module;

[0023] Figure 4 is a functional diagram of the transmitting circuit;

[0024] The following are the labeling elements in the diagram: 1. Circuit section; 11. First outer casing; 12. Integrated circuit module; 2. Pressure-bearing connector; 3. Acoustic section; 31. Second outer casing; 32. Metal rod; 33. Metal housing; 34. Sound insulation structure; 35. First transmitting crystal; 36. Second transmitting crystal; 37. Transmitting transformer; 38. First receiving crystal; 39. Second receiving crystal; 310. Third receiving crystal; 311. Fourth receiving crystal. Detailed Implementation

[0025] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the relevant invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, only the parts relevant to the invention are shown in the accompanying drawings.

[0026] It should be noted that, where there is no conflict, the embodiments and features in the embodiments of this utility model can be combined with each other. The present utility model will now be described in detail with reference to the accompanying drawings and embodiments.

[0027] Please refer to Figures 1-4. An embodiment of this utility model provides a cable-mounted digital acoustic logging tool, which includes a circuit section 1 and an acoustic section 3 arranged in series. The internal circuitry of the circuit section 1 and the internal circuitry of the acoustic section 3 are electrically connected through a pressure-bearing connector 2 to realize the transmission of signals.

[0028] The circuit section 1 includes a first housing 11, and an integrated circuit module 12 is fixedly disposed inside the first housing 11;

[0029] The acoustic section 3 includes a second outer shell 31. Inside the second outer shell 31, a metal rod 32 is fixedly installed along its height direction. The upper and lower ends of the metal rod 32 are fixed inside the second outer shell 31 by brackets to fix the metal rod 32. Two transmitting crystals, two transmitting transformers and four receiving crystals are fixedly installed on the metal rod 32. A sound insulation structure 34 is fixedly sleeved on the outer circumference of the metal rod 32. A metal chamber 33 is fixedly installed on the outer circumference of each transmitting crystal, transmitting transformer and receiving crystal. The interior of the metal chamber 33 is filled with silicone oil.

[0030] The second outer shell 31 is a grooved steel protective shell that supports the entire acoustic system. It has windows at the transducer (transmitting crystal and receiving crystal) positions to ensure that the acoustic energy waves radiating into the stratum and the acoustic signals propagating back from the stratum can reach the receiving probe.

[0031] The integrated circuit module 12 includes a circuit board on which a main control processing module, an acoustic data communication transmission module, a high-voltage transmission module, a signal conditioning module, and a power supply module are integrated. The main control processing module is electrically connected to the acoustic data communication transmission module, the high-voltage transmission module, the signal conditioning module, and the power supply module. The electronic components on the circuit board are fixed by silicone potting, and the first outer shell 11 is made of metal to suppress downhole electromagnetic noise.

[0032] The main control processing module is responsible for functions such as transmission control and signal acquisition, including transmission selection, multiplexed reception, and reception gain control. The main control processing module outputs a synchronization signal and a transmission control signal to trigger the high-voltage ignition circuit of the transmission circuit. The corresponding transmission probe is triggered by the high voltage, thus completing one transmission. When the main control processing module of the digital acoustic electronic circuit receives a data acquisition interruption from the ground, it simultaneously performs differential, filtering, and amplification reception on the four received signals. The received acoustic signals are converted by AD and processed by the main control processing module. Please refer to the schematic diagram of the receiver board shown in Figure 3 for details.

[0033] After completing one launch ignition and data processing, the digital acoustic wave immediately enters a waiting state for the next launch, and restarts again during the next ignition; the transmitting transducer receives a transmission voltage of approximately 4000V;

[0034] Signal conditioning module: dynamically adjusts the amplitude of the sound wave signal using a digital potentiometer; sets a bandpass filter to suppress noise interference;

[0035] Acoustic data communication transmission module: Receives control commands sent by the ground system and simultaneously uploads various measurement results such as acoustic time difference, waveform data, and temperature in real time;

[0036] High-voltage transmitting module: It generates 400V DC high voltage from 180V AC power supply. At the same time, it generates high-voltage narrow pulses (typical value: 400V / 5us) through the control signal of the main control processing module. Then, it is stepped up to about 4000V by the transmitting transformer in the acoustic system section, which is used to drive the first transmitting crystal and the second transmitting crystal to transmit and generate sound wave signals.

[0037] The layout of the digital acoustic wave main control receiving circuit EA is shown in Figure 3. The receiving circuit has two signal conditioning receiving boards, each with two independent receiving channels. Each channel has its own programmable gain for each transmission, and can select to process one received signal input. The channels on the A-side receiving board can be selected as Rec1, Rec2, or test channels; the channels on the B-side receiving board can be selected as Rec3, Rec4, or test channels. Its functions are shown in Figure 3.

[0038] The principle of the high-voltage transmitting circuit module is shown in Figure 4. The transmitting circuit board on the circuit frame is the high-voltage transmitting control circuit board.

[0039] The launch control circuit receives the launch ignition synchronization signal Fire from the data acquisition control circuit, thereby controlling the switching of the two launch pulse transformers. The primary of the pulse transformer connected to the launch crystal Tx1 (the first launch crystal) is connected to +415V and FIRE1; the primary of the pulse transformer connected to the launch crystal Tx2 (the second launch crystal) is connected to +415V and FIRE2; the energy storage capacitor C1 is also connected to +415V to power the launch transformers.

[0040] The receiving control electronic circuit sends the ignition control signal to the transmitting control circuit to trigger the corresponding transmitting crystal; the transmitting circuit generates a high voltage to the switching circuit to trigger the first transmitting crystal and the second transmitting crystal to transmit.

[0041] The pressure-bearing connector 2 is fixedly disposed inside the first housing 11, below the integrated circuit module 12. The pressure-bearing connector 2 is a double-sided connector. The integrated circuit module 12 connects its circuitry to one side of the pressure-bearing connector 2 via a female plug. All the circuitry inside the acoustic sub-section 3 connects its circuitry to the other side of the pressure-bearing connector 2 via another female plug. That is, the acoustic sub-section 3 connects to the circuit sub-section 1 through the pressure-bearing connector 2. The setting of the pressure-bearing connector 2 allows the sealed plug for transmitting pulses and the sealed plug for receiving signals to be installed on two different surfaces, effectively avoiding magnetic interference between the transmitted signal and the received signal at the connection point.

[0042] In a preferred embodiment, the interior of the metal rod 32 is hollow along its axial direction, and 18 through lines are all arranged inside the metal rod 32.

[0043] In a preferred embodiment, the sound insulation structure 34 is made of composite material, and a wire groove is provided on the sound insulation structure 34 along the height direction of the metal rod 32. The receiving crystal, the transmitting transformer and the circuit of the receiving crystal are all fixedly installed inside the wire groove.

[0044] That is, the through line inside the acoustic short section 3 is separated from the lines of the transmitting crystal, transmitting transformer and receiving crystal, and the wiring is carried out inside and outside the metal rod 32 respectively, which effectively improves the interference between the lines.

[0045] In a preferred embodiment, the composite material is made of low-velocity rubber.

[0046] In a preferred embodiment, one end of the first housing 11 is threadedly connected to one end of the second housing 31.

[0047] In a preferred embodiment, two transmitting crystals are arranged sequentially from top to bottom on the metal rod 32, namely a first transmitting crystal 35 (referred to as T1 in the figure) and a second transmitting crystal (referred to as T2 in the figure); the distance between the first transmitting crystal 35 and the second transmitting crystal 36 is set to 2 feet; the high voltage input leads of the two transmitting crystals are made of double-core shielded wires, which can avoid the interference of magnetic field on the receiving channel.

[0048] In a preferred embodiment, two transmitting transformers 37 are fixedly mounted on a metal rod 32 between the first transmitting crystal 35 and the second transmitting crystal 36.

[0049] In a preferred embodiment, four receiving crystals are arranged sequentially from top to bottom on the metal rod 32, below the second transmitting crystal 36. These are the first receiving crystal 38 (represented by R1 in the figure), the second receiving crystal 39 (represented by R2 in the figure), the third receiving crystal 310 (represented by R3 in the figure), and the fourth receiving crystal 311 (represented by R3 in the figure). The spacing between two adjacent receiving crystals is set to 0.5 feet. The response frequency range of the four receiving crystals is 1-20 kHz. The output leads of the receiving crystals are electrostatically shielded using double-core shielded wires. The metal rod 32 shields against interference. Each receiving line is routed separately. In order to be combined with other logging instruments, the acoustic section 3 has 18 through lines inside, which are routed inside the metal rod 32.

[0050] By using an array design of dual transmitters (first transmitting crystal 35, second transmitting crystal 36) and multiple receivers (first receiving crystal 38, second receiving crystal 39, third receiving crystal 310, fourth receiving crystal 311), the system automatically compensates for the influence of wellbore irregularities, mud intrusion, instrument tilt, and other factors on the measurement results, thereby improving data accuracy.

[0051] Each transmitting crystal, transmitting transformer, and receiving crystal is fixed to a metal rod 32 by a bracket, and each transmitting crystal, transmitting transformer, and receiving crystal is equipped with a metal compartment 33. The metal compartment 33 is fixed to the metal rod 32 or the corresponding bracket. The interior of the metal compartment 33 is filled with silicone oil, which protects the components inside the metal compartment 33 and allows the acoustic signal to be coupled outwards well.

[0052] In a preferred embodiment, the distance between the second transmitting crystal 36 and the first receiving crystal 38 is set to 3 feet.

[0053] In a preferred embodiment, the metal compartment 33 is made of stainless steel.

[0054] In the description of this specification, the terms "connection," "installation," and "fixing," etc., should be interpreted broadly. For example, "connection" can be a fixed connection, a detachable connection, or an integral connection; it can be 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 application according to the specific circumstances.

[0055] In the description of this specification, the terms "one embodiment," "some embodiments," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0056] The above are merely preferred embodiments of this application and are not intended to limit this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A cable-operated digital acoustic logging tool, characterized in that, The device includes a circuit section and an acoustic section arranged in series. The internal wiring of the circuit section and the internal wiring of the acoustic section are electrically connected through a pressure-bearing connector. The circuit section includes a first outer shell, inside which an integrated circuit module is fixedly disposed. The acoustic section includes a second outer shell, inside which a metal rod is fixedly disposed along its height. Two transmitting crystals, two transmitting transformers, and four receiving crystals are fixedly disposed on the metal rod. A sound insulation structure is fixedly sleeved on the circumferential outer side of the metal rod. Each transmitting crystal, transmitting transformer, and receiving crystal has a metal chamber fixedly disposed on its circumferential outer side, and the interior of the metal chamber is filled with silicone oil.

2. The cable-mounted digital acoustic logging tool according to claim 1, characterized in that, The interior of the metal rod is hollow along its axial direction, and 18 through lines are all installed inside the metal rod.

3. The cable-mounted digital acoustic logging tool according to claim 1, characterized in that, The sound insulation structure is made of composite material, and a groove is formed on the sound insulation structure along the height direction of the metal rod. The receiving crystal, the transmitting transformer and the circuit of the receiving crystal are all fixedly installed inside the groove.

4. The cable-mounted digital acoustic logging tool according to claim 3, characterized in that, The composite material is made of low-velocity rubber.

5. The cable-mounted digital acoustic logging tool according to claim 1, characterized in that, One end of the first housing is threaded to one end of the second housing.

6. The cable-mounted digital acoustic logging tool according to claim 1, characterized in that, The two emitting crystals are arranged sequentially from top to bottom on the metal rod, namely the first emitting crystal and the second emitting crystal; the distance between the first emitting crystal and the second emitting crystal is set to 2 feet.

7. The cable-mounted digital acoustic logging tool according to claim 6, characterized in that, The two transmitting transformers are fixedly mounted on the metal rod between the first transmitting crystal and the second transmitting crystal.

8. The wireline digital sonic tool of claim 7 wherein, The four receiving crystals are arranged in order from top to bottom on the metal rod below the second transmitting crystal, namely the first receiving crystal, the second receiving crystal, the third receiving crystal, and the fourth receiving crystal; the spacing between two adjacent receiving crystals is set to 0.5 feet.

9. The wireline digital sonic tool of claim 8 wherein, The distance between the second transmitting crystal and the first receiving crystal is set to 3 feet.

10. The cable-mounted digital acoustic logging tool according to claim 1, characterized in that, The metal compartment is made of stainless steel.

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