Neutron detection device and neutron logging system

Abstract

The invention discloses a neutron detection device and a neutron logging system.The neutron detection device comprises a neutron detection tube and a circuit board, the neutron detection tube is used for responding to neutron radiation and generating electric signals, the circuit board is arranged at one end of the neutron detection tube, and the signal output end of the neutron detection tube is connected with the input end of the circuit board; the circuit board is provided with an analog-to-digital conversion circuit, and the analog-to-digital conversion circuit is used for carrying out digital sampling on the electric signals to output digital signals. According to the neutron detection device, the circuit board is arranged at one end of the neutron detection tube, the circuit board is provided with the analog-to-digital conversion circuit, electric signals generated by the neutron detection tube can be digitally sampled and converted into digital signals to be transmitted, and compared with a traditional neutron detection device which transmits the electric signals generated by the neutron detection tube in an analog signal mode, the signal transmission efficiency is improved; the digital signal is not easy to introduce noise and is not easy to be interfered, so that the stability, the accuracy and the anti-interference performance of measurement can be improved.

Description

Technical Field

[0001] The present invention relates to the field of oil logging instruments, and particularly to a neutron detection device and a neutron logging system. Background Art

[0002] Neutron logging technology is a non-destructive detection method widely used in geological exploration and mineral resource development. It obtains information about formation composition, pore structure, etc. by measuring the characteristics of neutron radiation in underground rocks. Neutron logging plays an important role in the fields of oil, natural gas, hydrogeology, etc., and can be used to determine parameters such as the composition, water content, and porosity of underground rocks, which helps to evaluate the potential and recoverability of underground reservoirs.

[0003] However, there are some problems in the use of traditional neutron logging instruments. Among them, as one of the core components, the neutron detection device has weak signals and is easily affected by external interference, which directly affects the accuracy and stability of the measurement. The signal processing method of traditional neutron detection devices relies on analog amplification technology, but noise and interference are easily introduced during the transmission process of analog signals, thus affecting the reliability of the measurement data. Therefore, in order to improve the performance of neutron logging instruments, researchers have been working hard to find solutions to improve stability, accuracy, and anti-interference ability. Summary of the Invention

[0004] The purpose of the present invention is to provide a neutron detection device and a neutron logging system, which can improve the stability, accuracy, and anti-interference ability of the measurement.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] A neutron detection device includes a neutron detection tube and a circuit board. The neutron detection tube is used to respond to neutron radiation and generate an electrical signal. The circuit board is arranged at one end of the neutron detection tube. The signal output end of the neutron detection tube is connected to the input end of the circuit board. The circuit board is provided with an analog-to-digital conversion circuit, and the analog-to-digital conversion circuit is used to digitally sample the electrical signal to output a digital signal.

[0007] Optionally, the signal output end of the neutron detection tube is connected to the input end of the analog-to-digital conversion circuit.

[0008] Optionally, the range of the electrical signal sampled by the analog-to-digital conversion circuit includes 0 - 100 millivolts.

[0009] Optionally, the circuit board is further provided with an amplification circuit connected to the analog-to-digital conversion circuit, and the amplification circuit is used to amplify the digital signal.

[0010] Optionally, it further includes a connector connected to the circuit board, and the connector is used to connect to an external device.

[0011] Optionally, the circuit board is further provided with a first isolation circuit, and the digital signal output by the analog-to-digital conversion circuit is transmitted to the connector through the first isolation circuit.

[0012] Optionally, the circuit board is further provided with a second isolation circuit, and the power connection end of the circuit board is connected to the connector through the second isolation circuit.

[0013] Optionally, it further includes a shielding case, and the shielding case is encapsulated with one end face of the neutron detection tube, and the circuit board is arranged inside the shielding case.

[0014] Optionally, the signal output end of the neutron detection tube includes a signal output pin, and the signal output pin is connected to the input end of the circuit board.

[0015] A neutron logging system includes the neutron detection device according to any one of the above.

[0016] As can be seen from the above technical solutions, a neutron detection device provided by the present invention includes a neutron detection tube and a circuit board. The neutron detection tube is used to respond to neutron radiation and generate an electrical signal. The circuit board is arranged at one end of the neutron detection tube. The signal output end of the neutron detection tube is connected to the input end of the circuit board. The circuit board is provided with an analog-to-digital conversion circuit, and the analog-to-digital conversion circuit is used to perform digital sampling on the electrical signal to output a digital signal. The neutron detection device of the present invention arranges a circuit board at one end of the neutron detection tube, and the circuit board is provided with an analog-to-digital conversion circuit, which can digitally sample the electrical signal generated by the neutron detection tube and convert it into a digital signal for transmission. Compared with the traditional neutron detection device that transmits the electrical signal generated by the neutron detection tube as an analog signal, the digital signal is not easily introduced with noise and is not easily interfered, so that the measurement stability, accuracy and anti-interference ability can be improved.

[0017] A neutron logging system provided by the present invention can achieve the above beneficial effects. Description of the Drawings

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0019] Figure 1 It is a longitudinal sectional view of a neutron detection device provided by an embodiment of the present invention;

[0020] Figure 2 Schematic diagram of the circuit principle of a neutron detection device provided by an embodiment of the present invention.

[0021] Reference numerals in the accompanying drawings of the specification include:

[0022] 1 - Neutron detection tube, 2 - Signal output pin, 3 - Signal ground pin, 4 - Circuit board, 5 - Shielding case, 6 - Connector, 7 - First isolation circuit, 8 - Second isolation circuit. Specific embodiments

[0023] In order to enable those skilled in the art to better understand the technical solutions in the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0024] This embodiment provides a neutron detection device, including a neutron detection tube 1 and a circuit board 4. The neutron detection tube 1 is used to respond to neutron radiation and generate an electrical signal. The circuit board 4 is disposed at one end of the neutron detection tube 1. The signal output end of the neutron detection tube 1 is connected to the input end of the circuit board 4. The circuit board 4 is provided with an analog-to-digital conversion circuit, and the analog-to-digital conversion circuit is used to perform digital sampling on the electrical signal to output a digital signal.

[0025] In the neutron detection device of this embodiment, the circuit board 4 is disposed at one end of the neutron detection tube 1, and the circuit board 4 is provided with an analog-to-digital conversion circuit, which can perform digital sampling on the electrical signal generated by the neutron detection tube 1 and convert it into a digital signal for transmission. Compared with the traditional neutron detection device that transmits the electrical signal generated by the neutron detection tube as an analog signal, the digital signal is not easily introduced with noise and is not easily interfered, so that the measurement stability, accuracy, and anti-interference ability can be improved.

[0026] Exemplarily, reference can be made to Figure 1 and Figure 2 , Figure 1 Longitudinal sectional view of a neutron detection device provided by an embodiment, Figure 2 Schematic diagram of the circuit principle of a neutron detection device provided by an embodiment, as shown in Figure 1As shown, the circuit board 4 is disposed on one end face of the neutron detection tube 1. The neutron detection tube 1 is provided with a signal output pin 2 and a signal ground pin 3, and the signal output pin 2 and the signal ground pin 3 are respectively connected to the circuit board 4. It is possible that the signal output end of the neutron detection tube 1 includes the signal output pin 2, and the signal output pin 2 is connected to the input end of the circuit board 4. The signal output end of the neutron detection tube 1 of the present neutron detection device is connected to the circuit board 4 through the shortest path, and the analog-to-digital conversion circuit on the circuit board 4 digitally samples its electrical signal, avoiding the interference of the lead wire. This connection method reduces the noise and interference on the signal transmission path and improves the accuracy of the signal.

[0027] In this embodiment, the structure of the neutron detection tube 1 is not limited, as long as it can respond to neutron radiation and generate an electrical signal. The neutron detection tube 1 can be, but is not limited to, a He3 tube, and the He3 tube responds to neutron radiation and generates an electrical pulse signal.

[0028] In some embodiments, the signal output end of the neutron detection tube 1 is connected to the input end of the analog-to-digital conversion circuit, so that the electrical signal generated by the neutron detection tube 1 is input into the analog-to-digital conversion circuit, and the analog-to-digital conversion circuit digitally samples its electrical signal and converts it into a digital signal. In this way, the electrical signal generated by the neutron detection tube 1 is input into the analog-to-digital conversion circuit through the shortest path, thereby minimizing the interference and noise in the signal transmission process and improving the accuracy and stability of the signal. It can be understood that the analog-to-digital conversion circuit forms an acquisition circuit to obtain the electrical signal generated by the neutron detection tube 1 and digitally sample the electrical signal. Combined Figure 1 As shown, specifically, the signal output pin 2 of the neutron detection tube 1 is connected to the input end of the analog-to-digital conversion circuit. For example, the signal output pin 2 of the neutron detection tube 1 is directly connected to the input end of the analog-to-digital conversion circuit by welding.

[0029] In this embodiment, the circuit structure of the analog-to-digital conversion circuit is not limited, as long as it can digitally sample the electrical signal generated by the neutron detection tube 1. In some embodiments, the analog-to-digital conversion circuit has a small signal acquisition mode, that is, it can digitally sample small signals. Exemplarily, the range of electrical signals sampled by the analog-to-digital conversion circuit includes 0-100 millivolts. For example, a specific analog-to-digital conversion circuit can complete digital sampling of small signals of 0-30 millivolts. In this embodiment, the number of bits of the digital signal output by the analog-to-digital conversion circuit for digital sampling is not limited, and the number of bits of the digital signal output can be 24 bits, that is, 24-bit analog-to-digital conversion is performed on the electrical signal.

[0030] In some embodiments, the circuit board 4 is further provided with an amplification circuit connected to the analog-to-digital conversion circuit. The amplification circuit is used to amplify the digital signal. The digital signal generated by the analog-to-digital conversion circuit is transmitted to the amplification circuit, and the amplification circuit amplifies the digital signal. In traditional neutron detection devices, the electrical signal generated by the neutron detection tube is first amplified and then transmitted. However, noise and interference are easily introduced during the transmission of analog signals, which affects the accuracy, stability, and reliability of measurement data. In the neutron detection device of this embodiment, the electrical signal generated by the neutron detection tube 1 is first digitally sampled and then amplified, and is transmitted as a digital signal. Digital signals are not easily affected by noise and interference. Compared with amplifying analog signals, amplifying digital signals can avoid introducing amplification noise, thereby improving the stability, accuracy, and anti-interference ability of measurement. In this embodiment, the circuit structure of the amplification circuit is not limited.

[0031] In some embodiments, this neutron detection device further includes a connector 6 connected to the circuit board 4. The connector 6 is used to connect to an external device. Through the connector 6, the output signal of the circuit board 4 can be transmitted, and / or through the connector 6, a power source can be connected to supply power to each component of this neutron detection device.

[0032] Further, the circuit board 4 may also be provided with a first isolation circuit 7. The digital signal output by the analog-to-digital conversion circuit is transmitted to the connector 6 through the first isolation circuit 7. Through the first isolation circuit 7, the influence of post-stage signal interference on signal quality can be reduced, and the interference caused by the circuit board 4 to external devices can be reduced.

[0033] Further, the circuit board 4 may also be provided with a second isolation circuit 8. The power connection end of the circuit board 4 is connected to the connector 6 through the second isolation circuit 8. Through the second isolation circuit 8, external power supply noise can be reduced or even eliminated, and the interference caused by the neutron detection device to the external power supply can be reduced.

[0034] In this embodiment, the circuit structure of the first isolation circuit 7 is not limited, and the circuit structure of the second isolation circuit 8 is not limited. The first isolation circuit 7 may adopt, but is not limited to, a Serial Peripheral Interface (SPI) digital isolation circuit.

[0035] Due to the complexity of the underground environment, neutron logging instruments are often interfered with by underground rock formations and external electromagnetic fields. These interference signals may enter the system through channels such as the leads of sensors and circuit boards, resulting in distorted measurement results. In some embodiments, the neutron detection device further includes a shielding case 5. The shielding case 5 is encapsulated with one end face of the neutron detection tube 1, and the circuit board 4 is disposed inside the shielding case 5. The electromagnetic interference in the external space can be eliminated through the shielding case 5, preventing the interference signals of the external electromagnetic field from entering the circuit and ensuring the integrity of the signals of the neutron detection device. For reference Figure 1 As shown, the shielding case 5 is encapsulated with one end face of the neutron detection tube 1 to form a circuit chamber, and the circuit board 4 is inside the circuit chamber. The shielding case 5 is a metal box, which can encapsulate each circuit component of the circuit board 4 in a completely shielded metal box and is integrally encapsulated with the neutron detection tube 1.

[0036] The neutron detection device of this embodiment integrates an analog-to-digital conversion circuit on the circuit board and can directly output digitized detection data, which can solve the problems of weak signals and susceptibility to interference existing in existing neutron logging instruments. And through the processing of spatial shielding and circuit digital isolation, the measurement accuracy and stability of the neutron detection device can be effectively improved, providing a new solution for accurately obtaining underground geological information.

[0037] The neutron detection device of this embodiment is a front-end digital neutron detection device, which has the following characteristics and advantages:

[0038] 1. Front-end digital sampling: The front-end digital neutron detection device design is adopted to directly digitize and sample neutron signals. This method eliminates the interference in traditional analog signal transmission, thereby improving the measurement accuracy and reliability.

[0039] 2. Signal transmission along the shortest path: The signal output end of the neutron detection tube of the neutron detection device is directly connected to the input end of the circuit board through the shortest path, reducing the noise and interference on the signal transmission path and helping to improve the accuracy of the signal.

[0040] 3. High-precision small-signal acquisition: A 24-bit analog-to-digital conversion circuit is used for small-signal acquisition to achieve high-precision digital sampling of weak signals. Such a design not only reduces the noise introduced by analog amplification but also improves the sensitivity of signal capture.

[0041] 4. Interference suppression and data integrity: Through circuit isolation and metal box spatial shielding, external electromagnetic interference is effectively suppressed. Circuit isolation protects the signal from external power supply noise and interference, while the metal box shielding ensures the integrity of the signals of the neutron detection device.

[0042] 5. Improve anti-interference ability: By comprehensively considering the characteristics of front-end digitization, signal transmission path optimization, and interference isolation, the anti-interference ability of the neutron detection device is improved, making it more reliable and stable in complex underground environments.

[0043] 6. Wide practicality: This technology can be applied to geological exploration fields such as neutron logging instruments, providing a new solution for accurately obtaining underground geological information and having broad practical application prospects.

[0044] In summary, this front-end digitized neutron detection device has important application prospects in the field of neutron logging. Through the direct digital sampling of neutron detection signals and the use of processing means such as spatial shielding and circuit isolation, this technology effectively improves the stability and accuracy of the signals of the neutron detection device, providing a more accurate and reliable method for obtaining underground geological information for neutron logging instruments.

[0045] This embodiment also provides a neutron logging system, including the neutron detection device described in any one of the above embodiments.

[0046] In the neutron logging system of this embodiment, a circuit board is arranged at one end of the neutron detection tube of the neutron detection device. The circuit board is provided with an analog-to-digital conversion circuit, which can digitally sample the electrical signals generated by the neutron detection tube and convert them into digital signals for transmission. Compared with the traditional neutron detection device that transmits the electrical signals generated by the neutron detection tube as analog signals, digital signals are not easily introduced with noise and are not easily interfered, so that the stability, accuracy, and anti-interference ability of the measurement can be improved.

[0047] The above has introduced the neutron detection device and neutron logging system provided by the present invention in detail. Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention. It should be noted that for those of ordinary skill in the art of this technology, without departing from the principle of the present invention, several improvements and modifications can still be made to the present invention, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

Claims

1. A neutron detection device, characterized in that: It includes a neutron detection tube and a circuit board. The neutron detection tube is used to respond to neutron radiation and generate an electrical signal. The circuit board is arranged at one end of the neutron detection tube. The signal output end of the neutron detection tube is connected to the input end of the circuit board. The circuit board is provided with an analog-to-digital conversion circuit. The analog-to-digital conversion circuit is used to digitally sample the electrical signal to output a digital signal.

2. The neutron detection device according to claim 1, characterized in that: The signal output end of the neutron detection tube is connected to the input end of the analog-to-digital conversion circuit.

3. The neutron detection device according to claim 1, characterized in that: The range of the electrical signal sampled by the analog-to-digital conversion circuit includes 0-100 millivolts.

4. The neutron detection device according to claim 1, characterized in that: The circuit board is also provided with an amplifier circuit connected to the analog-to-digital conversion circuit, and the amplifier circuit is used to amplify the digital signal.

5. The neutron detection device according to claim 1, characterized in that: Also included is a connector connected to the circuit board, wherein the connector is used to connect to an external device.

6. The neutron detection device according to claim 5, characterized in that: The circuit board is also provided with a first isolation circuit, and the digital signal output by the analog-to-digital conversion circuit is transmitted to the connector through the first isolation circuit.

7. The neutron detection device according to claim 5, characterized in that: The circuit board is also provided with a second isolation circuit, and the power connection end of the circuit board is connected to the connector through the second isolation circuit.

8. The neutron detection device according to claim 1, characterized in that: It also includes a shielding shell, which is sealed with an end surface of the neutron detection tube, and the circuit board is arranged in the shielding shell.

9. The neutron detection device according to claim 1, characterized in that: The signal output end of the neutron detection tube includes a signal output pin, and the signal output pin is connected to the input end of the circuit board.

10. A neutron logging system, characterized in that: A neutron detection device comprising the neutron detection device according to any one of claims 1 to 9.

Images