CN115030710A - High-signal-to-noise-ratio sound wave receiving device for in-situ sound wave detection, production method and sound wave receiving method - Google Patents

Abstract

The invention discloses a sound wave receiving device for in-situ sound wave detection with high signal-to-noise ratio, a production method and a sound wave receiving method in the technical field of borehole sound wave detection. Acoustic wave receiving transducer, a plurality of acoustic wave receiving transducers are linearly distributed in the axial installation hole along the axial direction of the axial installation hole, used to receive the acoustic wave signal and output the analog signal; the digital signal sampling module, the digital signal sampling module and the The acoustic wave receiving transducers are alternately arranged and electrically connected in one-to-one correspondence for converting analog signals into digital signals. The invention adopts the alternate arrangement of the digital signal sampling module and the acoustic wave receiving transducer, shortens the transmission distance of the analog signal between the acoustic wave receiving transducer and the digital signal sampling module, and realizes the nearest digitization of the acoustic wave signal and the transmission of the electrical signal. Digital transmission can effectively reduce the influence of the external environment on the signal transmission process and improve the signal-to-noise ratio of signal transmission.

Description

An acoustic wave receiving device for in-situ acoustic wave detection with high signal-to-noise ratio, production method and the same Sound wave reception method

technical field

The invention relates to the technical field of borehole acoustic wave detection, in particular to an acoustic wave receiving device for in-situ acoustic wave detection with high signal-to-noise ratio, a production method and an acoustic wave receiving method.

Background technique

As one of the three conventional logging technologies (resistivity, radioactivity and acoustic wave), sonic logging detection technology has been widely and maturely applied in petroleum exploration logging. In recent years, related technologies have been tried to be used in the investigation and evaluation of marine engineering geological surveys.

The basic principle of acoustic detection logging is to obtain the speed of formation acoustic waves per hour through the different propagation speeds of acoustic waves in the formation, thereby reflecting the current drilling formation information, and to realize the electrical to Acoustic and sound-to-electrical conversion. When the acoustic wave detection instrument is working in the well, the transmitting acoustic system excites the transmitting acoustic source through the high-voltage excitation pulse to generate the acoustic wave signal. After entering the formation, it is transmitted through the formation and then reaches the receiver array. The receiver array arranged at a fixed distance from the transmitting acoustic source realizes the Conversion of received acoustic signals to electrical signals.

The acoustic wave transmitting transducer and the acoustic wave receiving transducer are passive devices mainly composed of piezoelectric ceramics. The acoustic wave signal received by the acoustic wave receiving transducer is converted into a weak electric signal through the piezoelectric ceramic material, and its amplitude varies with the drilling experience. The difference of the stratum is large. During the in-situ test of the surface stratum, the stratum is relatively loose. Therefore, the received acoustic wave amplitude signal is small, and the signal needs to be processed by automatic gain control and filter amplification to improve the signal-to-noise ratio.

As shown in FIG. 6 , the in-situ acoustic wave detection instrument includes a receiving circuit sub-section 400 and a receiving acoustic system sub-section 500, and the receiving circuit sub-section 400 and the receiving acoustic system sub-section 500 are connected and fixed by a connecting part 600; A plurality of acoustic wave receiving transducers 200 arranged at equal intervals are arranged in the acoustic system short section 500, and a plurality of digital signal sampling modules 300 electrically connected to the acoustic wave receiving transducers 200 in a one-to-one correspondence are arranged in the receiving circuit short section 400 , the digital signal sampling module 3000 is used to convert the sound wave signal received by the sound wave receiving transducer 200 into a digital signal and output it to the terminal. The in-situ acoustic wave detection instrument with the above structure has the advantage of simple arrangement of the acoustic wave receiving transducer, and is widely used in acoustic logging. However, in the actual use process, it is found that the existing in-situ acoustic wave detection instruments have the disadvantage that the signal is easily affected by the external environment, and the noise will increase.

In addition, for the existing in-situ acoustic wave detection instruments, when installing the acoustic wave receiving transducer, in order to facilitate the coupling of the acoustic wave signal, multiple acoustic wave receiving transducers are often placed at equal intervals in the rubber filled with silicone oil. In the skin bag environment, and seal both ends of the skin bag. The above-mentioned packaging method is very cumbersome in the actual operation process, especially in the process of injecting silicone oil into the skin, it is necessary to use a vacuum device to extract all the air in the skin. At the same time, the two ends of the bag also need special tools (metal straps) to seal, if the seal is not handled properly, it will cause leakage of silicone oil.

SUMMARY OF THE INVENTION

After long-term research, the inventor found that the existing in-situ acoustic wave detection instruments set the acoustic wave receiving transducer separately in the short section of the receiving acoustic system, and separately set the digital signal sampling module in the short section of the receiving circuit, resulting in a one-to-one correspondence. The distance between the electrically connected acoustic wave receiving transducer and the digital signal sampling module is relatively far (more than 100cm); when the acoustic wave receiving transducer receives the acoustic wave signal, the acoustic wave receiving transducer will send the digital signal to the digital signal through the conversion of the acoustic and electrical signal. The sampling module sends a weak current signal, which needs to be amplified, filtered and converted into a digital signal in the digital signal sampling module, but the weak current signal is an analog signal, which is long-term between the acoustic wave receiving transducer and the digital signal sampling module. In the process of distance transmission, the analog signal is easily affected by the external environment, and the noise will increase, thereby reducing the signal-to-noise ratio of the signal.

In view of this, the purpose of the present invention is to provide an acoustic wave receiving device for in-situ acoustic wave detection with high signal-to-noise ratio, so as to solve the technical problem of low signal-to-noise ratio of the existing acoustic wave receiving device.

The technical scheme adopted by the present invention is: an acoustic wave receiving device for in-situ acoustic wave detection with high signal-to-noise ratio, comprising:

an installation frame, and the circumference of the installation frame is evenly distributed with axial installation holes;

an acoustic wave receiving transducer, a plurality of the acoustic wave receiving transducers are linearly distributed in the axial installation hole along the axial direction of the axial installation hole, and are used for receiving acoustic wave signals and outputting analog signals;

A digital signal sampling module, the digital signal sampling module and the acoustic wave receiving transducer are alternately arranged in the axial installation hole, and are electrically connected one by one, for converting the analog signal output by the acoustic wave receiving transducer into a digital signal Signal.

Preferably, the digital signal sampling module includes a preamplifier circuit, a band-pass filter circuit, an automatic gain control circuit and an analog-to-digital conversion circuit which are connected in series in sequence.

Preferably, the number of the axial mounting holes is 4 or 8.

Preferably, each of the axial mounting holes is provided with 4, 6 or 8 acoustic wave receiving transducers at equal intervals.

Preferably, the acoustic wave receiving transducer includes a dual-polarized piezoelectric ceramic tube.

Preferably, the distance between the digital signal sampling module and the acoustic wave receiving transducer electrically connected to it is less than half of the distance between two adjacent acoustic wave receiving transducers, so as to convert the analog signal output by the acoustic wave receiving transducer into a digital signal nearby. Signal.

Preferably, the acoustic wave receiving transducer and the digital signal sampling module are encapsulated in the axial installation hole by insulating epoxy resin.

The second object of the present invention is to provide a method for producing an acoustic wave receiving device for in-situ acoustic wave detection with a high signal-to-noise ratio, the method comprising the following steps:

S10: individually encapsulate the acoustic wave receiving transducer and the digital signal sampling module;

S20: The packaged acoustic wave receiving transducer and the digital signal sampling module are alternately arranged on the mounting skeleton along the axial direction, and are electrically connected in one-to-one correspondence;

S30: Encapsulate the acoustic wave receiving transducer and the digital signal sampling module as a whole.

Preferably, both S10 and S30 are potted with insulating epoxy resin.

The third object of the present invention is to provide a high signal-to-noise ratio sound wave receiving method for in-situ sound wave detection, the method comprising the following steps:

S10: Receive the sound wave signal through the sound wave receiving transducer and convert it into an analog signal;

S20: Convert the analog signal into a digital signal nearby by using a digital signal sampling module alternately arranged with the acoustic wave receiving transducer along the axis direction;

S30: Send the digital signal to the outside through the digital signal sampling module.

Beneficial effects of the present invention:

1. The present invention adopts the nearest digitization method. First, the acoustic wave receiving transducers are arranged in the axial mounting holes of the mounting frame at equal intervals, and then the digital signal sampling module and the acoustic wave receiving transducer are alternately arranged, and correspond one by one. The electrical connection shortens the transmission distance of the analog signal between the acoustic wave receiving transducer and the digital signal sampling module, realizes the nearby digitization of the acoustic wave signal and the digital transmission of the electrical signal, which can effectively reduce the influence of the external environment on the signal transmission process. , to improve the signal-to-noise ratio of signal transmission.

2. The present invention adopts the epoxy resin potting method to encapsulate the alternately arranged acoustic wave receiving transducers and digital signal sampling modules in the axial mounting holes of the mounting skeleton, which can not only ensure the coupling of acoustic wave signals and the exchange of acoustic wave receiving. The insulation treatment of the energy device also realizes the digitization of the sound wave signal nearby, improves the signal-to-noise ratio of signal transmission, and has the advantages of large amount of information for the acquisition of sound wave signal data and easy installation.

Description of drawings

Fig. 1 is the structural representation of the high signal-to-noise ratio in-situ acoustic wave detection sound wave receiving device of the present invention;

Fig. 2 is the top view of the installation frame of the present invention;

Fig. 3 is the perspective view of the installation frame of the present invention;

Fig. 4 is the package structure diagram of the acoustic wave receiving transducer and the digital signal sampling module in the axial mounting hole;

5 is a schematic diagram of a signal collected in a single direction;

FIG. 6 is a schematic structural diagram of a conventional acoustic wave receiving device.

Description of the reference numbers in the figure:

100. Install the skeleton;

110, axial mounting hole; 120, cylinder; 130, central through hole;

200. Sound wave receiving transducer;

300. Digital signal sampling module;

400. Short section of receiving circuit;

500, receiving sound system short section;

600. Connection part.

Detailed ways

The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings. These embodiments are only used to illustrate the present invention, but not to limit the present invention.

In the description of the present invention, it should be noted that the terms "center", "portrait", "horizontal", "top", "bottom", "front", "rear", "left", "right", " The orientations or positional relationships indicated by vertical, horizontal, top, bottom, inside, and outside are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying It is described, rather than indicated or implied, that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as limiting the invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed to indicate or imply relative importance.

In the description of the present invention, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense, unless otherwise expressly specified and limited, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

Also, in the description of the present invention, unless otherwise specified, "plurality" means two or more.

Embodiment 1, as shown in Figures 1 to 4, an acoustic wave receiving device for in-situ acoustic wave detection with high signal-to-noise ratio, comprising:

The mounting frame 100 is provided with axial mounting holes 110 evenly distributed on the circumference of the mounting frame 100 .

For the acoustic wave receiving transducer 200, a plurality of acoustic wave receiving transducers 200 are linearly distributed in each axial mounting hole 110 along the axial direction of the axial mounting hole 110, for receiving acoustic wave signals and outputting analog signals.

The digital signal sampling module 300, the digital signal sampling module 300 and the acoustic wave receiving transducer 200 are alternately arranged in the axial mounting hole 110, and are electrically connected one by one, for converting the analog signal output by the acoustic wave receiving transducer 200 into a Digital signal.

The present application adopts the nearest digitization method. First, the acoustic wave receiving transducers 200 are arranged in the axial installation holes 110 of the mounting frame 100 at equal intervals, and then the digital signal sampling module 300 and the acoustic wave receiving transducers 200 are alternately arranged, and The one-to-one electrical connection reduces the transmission distance of the analog signal between the acoustic wave receiving transducer 200 and the digital signal sampling module 300, realizes the digitization of the acoustic wave signal and the digitized transmission of the electrical signal, and can effectively reduce the impact of the external environment on the signal. The influence of the transmission process, improve the signal-to-noise ratio of signal transmission.

In a specific embodiment, as shown in FIG. 2 , the digital signal sampling module 300 includes a circuit board, on which a preamplifier circuit, a bandpass filter circuit, an automatic gain control circuit and an analog-to-digital conversion are sequentially connected in series. circuit; wherein, after the acoustic wave receiving transducer 200 receives the acoustic wave signal, a weak current signal is generated through the conversion of the acoustic and electrical signal, but the weak current signal is an analog signal, and is transmitted to the digital signal sampling module 300; in the digital signal sampling module 300, The preamplifier circuit is used to amplify the weak current signal; the driving filter circuit is used to band-pass filter the amplified weak current signal to remove the clutter in the analog signal; the automatic gain control circuit is used to filter the weak current signal. Automatic gain control; the digital conversion circuit is used to perform digital-to-analog conversion on the weak current signal after gain, and output the digital signal, so as to realize the nearest digitization of the acoustic signal and improve the signal-to-noise ratio of signal transmission.

Wherein, the size (width and thickness) of the circuit board of the digital signal sampling module 300 should be equivalent to the size of the dual-polarized piezoelectric ceramic tube of the acoustic wave receiving transducer 200, so that the digital signal sampling module 300 and the acoustic wave receiving transducer can be ensured. 200 was successfully packaged at one time within a unified scale.

In a specific embodiment, as shown in FIGS. 3 and 4 , the mounting frame 100 includes a column body 120 and a central through hole 130 , and the central through hole 130 is coaxially disposed on the column body 120 , so that the cross section of the column body 120 is Circular; on the side wall of the cylinder 120 , there are 4 or 8 axial mounting holes 110 evenly distributed around the axis of the cylinder 120 , and the axial mounting holes 110 pass through both ends of the cylinder 120 . The reason for this setting is that: there are 4 or 8 axial mounting holes 110 evenly distributed around the circumference of the mounting frame 100, and by arranging the acoustic wave receiving transducer 200 and the digital signal sampling module 300 in each axial mounting hole 110, With the sound wave receiving transducer 200 receiving the sound wave signal in a specific direction, the receiving of the sound wave signal in four or eight directions is realized, and the accuracy of the sound wave signal receiving is improved.

Preferably, as shown in FIGS. 1 and 2 , each axial mounting hole 110 is provided with 4, 6 or 8 acoustic wave receiving transducers 200 at equal intervals; wherein, two adjacent acoustic wave receiving transducers 200 distance is 152.4mm. This setting is because: a plurality of acoustic wave receiving transducers 200 are arranged at equal intervals in each axial installation hole 110, and by setting the distance between two adjacent acoustic wave receiving transducers 200, the propagation of acoustic wave signals can be accurately calculated duration.

More preferably, the acoustic wave receiving transducer 200 includes a dual-polarized piezoelectric ceramic tube. This arrangement is because the dual-polarized piezoelectric ceramic tube has the advantages of small size and high sensitivity, which can not only reduce the radial size of the acoustic wave receiving device, but also improve the sensitivity and accuracy of the acoustic wave receiving device.

Among them, the size specifications of the dual-polarized piezoelectric ceramic tube, including height, inner diameter and outer diameter, should consider the overall size of the mounting frame 100 to ensure that the mounting holes in the eight circumferential directions of the mounting frame 100 are between.

In a specific embodiment, as shown in FIG. 1 and FIG. 2 , the distance between the digital signal sampling module 300 and the acoustic wave receiving transducer 200 electrically connected to it is less than half of the distance between the adjacent two acoustic wave receiving transducers 200, for The analog signal outputted after the acoustic wave signal received by the acoustic wave receiving transducer 200 is converted into a digital signal. The reason for this setting is that: the smaller the distance between the digital signal sampling module 300 and the acoustic wave receiving transducer 200, the shorter the transmission distance of the analog signal, the less affected by the external environment, and the higher the signal-to-noise ratio.

In a specific embodiment, as shown in FIG. 1 and FIG. 2 , the axially arranged acoustic wave receiving transducer 200 and the digital signal sampling module 300 are integrally encapsulated in the axial mounting hole 110 by insulating epoxy resin. This setting is because: in the existing in-situ acoustic wave detection instruments, when the acoustic wave receiving transducer 200 is installed, in order to facilitate the coupling of acoustic wave signals, a plurality of acoustic wave receiving transducers 200 are often placed at equal intervals. In the rubber bladder environment filled with silicone oil, there is not only the risk of silicone oil leakage, but also it is impossible to realize the close setting of the digital signal sampling module 300 and the acoustic wave receiving transducer 200, resulting in the inability to realize the close digitization of the acoustic wave signal. When using epoxy resin to encapsulate the acoustic wave receiving transducer 200 and the digital signal sampling module 300, because the epoxy index can be cured, there is no risk of liquid leakage, the installation process of the acoustic wave receiving transducer 200 can be simplified, and the acoustic wave receiving device can be improved. Production efficiency, and reduce production costs and use risks.

Embodiment 2, a production method of a high signal-to-noise ratio in-situ acoustic wave detection acoustic wave receiving device, the method comprises the following steps:

S10: Individually encapsulate the plurality of acoustic wave receiving transducers 200 and the plurality of digital signal sampling modules 300 individually by using insulating epoxy resin.

S20: Arrange the packaged acoustic wave receiving transducer 200 and the digital signal sampling module 300 alternately in the axial mounting hole 110 of the mounting frame 100 in the axial direction, and sample the acoustic wave receiving transducer 200 and the digital signal that are close to each other The modules 300 are electrically connected in one-to-one correspondence.

S30: Use insulating epoxy resin to integrally encapsulate the 4-8 acoustic wave receiving transducers 200 and the digital signal sampling module 300 in each axial mounting hole 110.

Embodiment 3, an acoustic wave receiving method for in-situ acoustic wave detection with high signal-to-noise ratio, the method comprising the following steps:

S10: Receive the sound wave signal through the sound wave receiving transducer 200 and convert it into an analog signal.

S20: The analog signal is converted into a digital signal nearby through the digital signal sampling module 300 arranged alternately with the acoustic wave receiving transducer 200 along the axis direction.

S30: The digital signal is sent to the outside through the digital signal sampling module 300.

Specifically, as shown in FIG. 5 , under the electric field excitation source of 3Khz, 8 acoustic wave receiving transducers 200 are linearly arranged in each axial mounting hole 110 of the acoustic wave receiving device, and the acoustic wave receiving device is used to conduct acoustic wave Signal reception, 8 digital signals can be collected in one direction.

Compared with the prior art, the present application at least has the following beneficial technical effects:

In the present application, epoxy resin is used to encapsulate the acoustic wave receiving transducer 200 , which can not only ensure the coupling of acoustic wave signals, but also ensure the insulation treatment of the acoustic wave receiving transducer 200 . In addition, the present application also performs epoxy resin potting on the digital signal sampling module 300 (control circuit) electrically connected to the acoustic wave receiving transducer 200, and the acoustic wave receiving transducer 200 and the digital signal sampling module are sealed by epoxy resin. 300 integrated package as a whole, realizes the nearest digitization of sound wave signal, improves the signal-to-noise ratio of signal transmission, and then realizes the preprocessing and digital acquisition of the array sound wave receiving signal of the in-situ acoustic detection instrument for marine engineering geological drilling, and has the sound wave Signal data acquisition has the advantages of large amount of information, easy installation and integrated design.

The present application adopts the method of nearest digitization, digitizes the analog signal after the acoustic-electrical conversion of the acoustic wave receiving transducer 200, and then transmits the collected waveform to the receiving sound system through the digital signal for subsequent data processing, which shortens the transmission of the analog signal. The distance reduces the influence of the external environment on the signal and improves the signal-to-noise ratio of signal transmission.

In the all-digital method adopted in this application, the acoustic wave receiving transducer 200 and the digital signal sampling module 300 are arranged in close proximity, and are encapsulated in an integrated epoxy resin, so as to realize all-digital data sampling and improve the signal-to-noise ratio of the signal. .

The above are only the preferred embodiments of the present invention. It should be pointed out that for those skilled in the art, without departing from the technical principle of the present invention, several improvements and replacements can be made. These improvements and replacements It should also be regarded as the protection scope of the present invention.

Claims (10)

1. An acoustic wave receiving apparatus for in-situ acoustic wave detection with a high signal-to-noise ratio, comprising:

the mounting structure comprises a mounting framework (100), wherein axial mounting holes (110) are uniformly distributed on the circumference of the mounting framework (100);

the acoustic wave receiving transducers (200) are linearly distributed in the axial mounting hole (110) along the axial direction of the axial mounting hole (110) and used for receiving acoustic wave signals and outputting analog signals;

the digital signal sampling module (300) and the sound wave receiving transducer (200) are alternately arranged in the axial mounting hole (110), are electrically connected in a one-to-one correspondence manner and are used for converting analog signals output by the sound wave receiving transducer (200) into digital signals.

2. The acoustic wave receiving device for in-situ acoustic wave detection with high signal-to-noise ratio according to claim 1, wherein the digital signal sampling module (300) comprises a pre-amplification circuit, a band-pass filter circuit, an automatic gain control circuit and an analog-to-digital conversion circuit, which are connected in series in sequence.

3. A high signal-to-noise ratio in-situ acoustic detection receiver apparatus according to claim 1, wherein the number of said axial mounting holes (110) is 4 or 8.

4. A high signal-to-noise ratio in-situ acoustic receiver apparatus for acoustic detection according to claim 1 wherein 4, 6 or 8 acoustic receiving transducers (200) are equally spaced in each of said axial mounting holes (110).

5. A high signal-to-noise ratio acoustic wave receiver for in-situ acoustic detection according to claim 1, wherein the acoustic wave receiving transducer (200) comprises a dual-polarized piezoelectric ceramic tube.

6. The acoustic wave receiving device for in-situ acoustic wave detection with high signal-to-noise ratio according to claim 1, wherein the distance from the digital signal sampling module (300) to the acoustic wave receiving transducer (200) electrically connected therewith is less than half of the distance between two adjacent acoustic wave receiving transducers (200), and is used for converting an analog signal output by the acoustic wave receiving transducer (200) into a digital signal nearby.

7. The acoustic receiver device for in-situ acoustic detection with high signal-to-noise ratio according to any one of claims 1 to 6, wherein the acoustic receiving transducer (200) and the digital signal sampling module (300) are potted in the axial mounting hole (110) through insulating epoxy resin.

8. A method for producing an acoustic receiver for in-situ acoustic detection with high signal-to-noise ratio, the method comprising the steps of:

s10: respectively carrying out individual packaging on the sound wave receiving transducer (200) and the digital signal sampling module (300);

s20: the packaged sound wave receiving transducer (200) and the digital signal sampling module (300) are alternately arranged on the mounting framework (100) along the axial direction and are electrically connected in a one-to-one correspondence manner;

s30: the acoustic wave receiving transducer (200) and the digital signal sampling module (300) are integrally packaged.

9. The method of claim 8, wherein the S10 and S30 are encapsulated with an insulating epoxy resin.

10. A sound wave receiving method for in-situ sound wave detection with high signal-to-noise ratio is characterized by comprising the following steps:

s10: receiving an acoustic signal by an acoustic receiving transducer (200) and converting the acoustic signal into an analog signal;

s20: converting the analog signal into a digital signal nearby through a digital signal sampling module (300) which is alternately arranged with the sound wave receiving transducer (200) along the axial direction;

s30: the digital signal is fed out by a digital signal sampling module (300).

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