Underground quartz resonant pressure sensor

Abstract

The utility model relates to the technical field of pressure sensors, and discloses an underground quartz resonant pressure sensor, which comprises a sealed shell, a corrugated pipe, a chip clamp, a supporting structure and a quartz chip, a base is fixedly installed at the bottom of the sealing shell. An electromagnetic shielding layer is fixedly arranged on the inner wall of the sealing shell, and a buffering anti-corrosion structure is arranged on the outer wall of the sealing shell. The corrugated pipe is mounted at the top of the sealing shell, and the bottom of the corrugated pipe extends into the sealing shell; the supporting structure is installed on the base and located in the sealing shell. The chip clamp is installed on the supporting structure and connected with two electrode columns, and the two electrode columns extend to the position below the base. The quartz chip is mounted on the chip clamp; the bottom of the corrugated pipe contacts with the surface of the quartz chip. According to the utility model, real-time monitoring of underground pressure can be realized, underground electromagnetic noise can be effectively blocked, the environmental adaptability and the working stability of the sensor are improved, and the precision of pressure monitoring is improved.

Description

Technical Field

[0001] This utility model relates to the field of pressure sensor technology, and in particular to a downhole quartz resonant pressure sensor. Background Technology

[0002] In the extraction of resources such as oil and natural gas, real-time monitoring of downhole pressure is crucial for ensuring safe production and optimizing extraction efficiency. Traditional downhole pressure sensors face numerous challenges in the complex downhole environment. On the one hand, strong electromagnetic interference exists downhole, and the signal transmission of ordinary sensors is easily affected by electromagnetic noise, leading to signal distortion and inaccurate monitoring data. On the other hand, the downhole environment is harsh, with frequent vibrations and the potential presence of corrosive media, such as corrosive gases and liquids in acidic gas fields, which can damage the sensor structure, shorten its lifespan, and reduce the reliability and stability of monitoring.

[0003] To address this, a downhole quartz resonant pressure sensor is proposed. Utility Model Content

[0004] The purpose of this invention is to provide a downhole quartz resonant pressure sensor, which aims to solve or improve at least one of the aforementioned technical problems.

[0005] To achieve the above objectives, this utility model provides the following solution: This utility model provides a downhole quartz resonant pressure sensor, comprising:

[0006] A sealed housing, the bottom of which is fixedly mounted with a base; an electromagnetic shielding layer is fixedly provided on the inner wall of the sealed housing, and a buffer and anti-corrosion structure is provided on the outer wall of the sealed housing;

[0007] A bellows, which is installed on the top of the sealed housing and whose bottom extends into the sealed housing;

[0008] A support structure is mounted on the base and is located within the sealed housing;

[0009] A chip clamp is mounted on the support structure and is connected to two electrode posts, which extend below the base.

[0010] A quartz chip is mounted on the chip fixture; the bottom of the bellows contacts the surface of the quartz chip, and the two sides of the quartz chip are respectively connected to the two electrode posts;

[0011] A sealing structure is installed between the bellows and the sealed outer shell.

[0012] According to the present invention, a downhole quartz resonant pressure sensor is provided, wherein a through hole is installed at the top center of the sealed housing, and the bottom of the bellows passes through the through hole. The sealing structure includes a first fluororubber O-ring, which is fixedly installed on the inner wall of the through hole. The inner wall of the through hole and the outer wall of the bellows both abut against the first fluororubber O-ring.

[0013] According to the present invention, a downhole quartz resonant pressure sensor is provided, wherein the buffer and anti-corrosion structure includes a buffer layer and an anti-corrosion coating. The buffer layer is fixedly sleeved on the outer wall of the sealed housing, and the anti-corrosion coating is disposed on the outer wall of the buffer layer.

[0014] According to the present invention, a downhole quartz resonant pressure sensor is provided, wherein the chip holder includes two symmetrically arranged clamping rods, and clamping heads are installed on the opposite end faces of the two clamping rods. The quartz chip is detachably connected between the two clamping heads, and the two electrode posts are respectively connected to the two clamping rods.

[0015] According to the present invention, a downhole quartz resonant pressure sensor is provided, wherein the support structure includes a positioning column, a central groove is provided through the center of the positioning column, and two mounting grooves are provided on the top surface of the positioning column, and the two clamping rods are respectively installed in the two mounting grooves.

[0016] The bottom surface of the positioning post has two vertical grooves arranged side by side, and the two vertical grooves are respectively connected to the two mounting grooves; the two electrode posts are installed in the two vertical grooves, and a number of second fluororubber O-rings are installed between the electrode posts and the vertical grooves at intervals.

[0017] According to the present invention, a downhole quartz resonant pressure sensor is provided, wherein two through slots are provided on the base, and the bottoms of the two electrode posts extend through the through slots to the bottom of the base, and the inner diameter of the through slots is smaller than the inner diameter of the vertical slots.

[0018] According to the present invention, a downhole quartz resonant pressure sensor is provided, wherein the quartz chip is an AT-cut quartz chip.

[0019] The present invention discloses the following technical effects:

[0020] This invention converts downhole pressure into mechanical displacement through a bellows. When external pressure is applied to the bellows, its axial deformation is transmitted to the surface of the quartz chip through the support structure. Under pressure, the quartz chip generates thickness shear mode vibration, and its resonant frequency is linearly related to the pressure. The two sides of the chip are connected to the external circuit through electrode posts, thereby converting the frequency change into a pressure value and realizing real-time monitoring of downhole pressure.

[0021] This invention effectively blocks downhole electromagnetic noise through an electromagnetic shielding layer, ensuring signal transmission integrity and providing a stable environment for signal transmission. It is suitable for environments with strong electromagnetic interference and effectively improves the accuracy of pressure monitoring.

[0022] This invention can absorb vibration energy in the downhole environment through a buffer and corrosion-resistant structure, reducing the impact of vibration on the sensor structure and lowering the risk of component loosening and damage caused by vibration. At the same time, it can effectively block corrosive media, enabling the sensor to adapt to extreme working conditions such as acidic gas fields. It can work normally even in highly corrosive environments, improving the environmental adaptability and working stability of the sensor and providing reliable protection for downhole pressure monitoring.

[0023] This invention effectively prevents downhole liquids, gases, and other media from entering the sensor by installing a sealing structure between the bellows and the sealed outer shell. This avoids damage to core components such as the quartz chip and electrode posts, ensuring the stability and reliability of the sensor's internal structure, preventing short circuits and corrosion caused by media intrusion, and extending the sensor's service life. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of this utility model;

[0026] Figure 2 for Figure 1 A magnified view of part A in the image;

[0027] Figure 3 for Figure 1 A magnified view of part B in the image.

[0028] The components include: 1. Sealed outer shell; 2. Base; 3. Electromagnetic shielding layer; 4. Bellows; 5. Quartz chip; 6. Through hole; 7. First fluororubber O-ring seal; 8. Buffer layer; 9. Anti-corrosion coating; 10. Fixture connecting rod; 11. Fixture head; 12. Positioning post; 13. Center groove; 14. Mounting groove; 15. Vertical groove; 16. Second fluororubber O-ring seal; 17. Through groove. Detailed Implementation

[0029] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0030] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0031] Reference Figures 1-3 This utility model provides a downhole quartz resonant pressure sensor, comprising:

[0032] A sealed outer shell 1 is provided, and a base 2 is fixedly installed at the bottom of the sealed outer shell 1; an electromagnetic shielding layer 3 is fixedly provided on the inner wall of the sealed outer shell 1, and a buffer anti-corrosion structure is provided on the outer wall of the sealed outer shell 1; the electromagnetic shielding layer 3 can be made of materials such as copper, aluminum, iron, silicon steel, and composite shielding materials, and no specific limitation is made in this embodiment;

[0033] Bellows 4 is installed on the top of the sealing housing 1, and the bottom of the bellows 4 extends into the sealing housing 1.

[0034] A support structure is mounted on the base 2 and is located inside the sealed housing 1;

[0035] The chip fixture is mounted on the support structure and is connected to two electrode posts that extend below the base 2.

[0036] Quartz chip 5 is mounted on a chip fixture; the bottom of the bellows 4 contacts the surface of the quartz chip 5, and the two sides of the quartz chip 5 are respectively connected to two electrode posts.

[0037] A sealing structure is installed between the bellows 4 and the sealed outer shell 1;

[0038] With this configuration, the present invention converts downhole pressure into mechanical displacement through the bellows 4. When external pressure is applied to the bellows 4, its axial deformation is transmitted to the surface of the quartz chip 5 through the support structure. Under the action of pressure, the quartz chip 5 generates thickness shear mode vibration, and its resonant frequency is linearly related to the pressure. The two sides of the quartz chip 5 are connected to the external circuit through electrode posts, thereby converting the frequency change into pressure value and realizing real-time monitoring of downhole pressure.

[0039] This invention effectively blocks downhole electromagnetic noise through the electromagnetic shielding layer 3, ensuring the integrity of signal transmission and providing a stable environment for signal transmission. It is suitable for environments with strong electromagnetic interference and effectively improves the accuracy of pressure monitoring.

[0040] This invention can absorb vibration energy in the downhole environment through a buffer and corrosion-resistant structure, reducing the impact of vibration on the sensor structure and lowering the risk of component loosening and damage caused by vibration. At the same time, it can effectively block corrosive media, enabling the sensor to adapt to extreme working conditions such as acidic gas fields. It can work normally even in highly corrosive environments, improving the environmental adaptability and working stability of the sensor and providing reliable protection for downhole pressure monitoring.

[0041] This invention effectively prevents downhole liquids, gases, and other media from entering the sensor by installing a sealing structure between the bellows 4 and the sealed housing 1. This avoids damage to core components such as the quartz chip 5 and electrode posts, ensuring the stability and reliability of the sensor's internal structure, preventing short circuits and corrosion caused by media intrusion, and extending the sensor's service life.

[0042] Further optimization of the scheme: a through hole 6 is installed through the center of the top of the sealing shell 1, and the bottom of the bellows 4 is installed through the through hole 6. The sealing structure includes a first fluororubber O-ring 7, which is fixedly installed on the inner wall of the through hole 6. The inner wall of the through hole 6 and the outer wall of the bellows 4 are both in contact with the first fluororubber O-ring 7.

[0043] Because fluororubber possesses excellent corrosion resistance, oil resistance, and good elasticity, during installation, the inner wall of the through-hole 6 and the outer wall of the bellows 4 compress the first fluororubber O-ring 7, causing it to undergo elastic deformation and tightly fill the gap between them. This effectively prevents downhole liquids, gases, and other media from entering the sensor through the gap between the through-hole 6 and the bellows 4, avoiding corrosion of core components such as the quartz chip 5 and electrode posts, ensuring the stability of the sensor's internal structure, preventing short circuits, corrosion, and other problems, and extending the sensor's service life.

[0044] The scheme is further optimized. The buffer and anti-corrosion structure includes a buffer layer 8 and an anti-corrosion coating 9. The buffer layer 8 is fixedly sleeved on the outer wall of the sealed shell 1, and the anti-corrosion coating 9 is disposed on the outer wall of the buffer layer 8.

[0045] The buffer layer 8 is made of a material with high elasticity and energy absorption properties, such as rubber or special foam material. When vibration occurs in the downhole environment, the buffer layer 8 can absorb vibration energy through its own elastic deformation, converting the impact force generated by the vibration into its own deformation energy, thereby reducing the impact of vibration on the sealing shell 1 and internal structure, and reducing the risk of component loosening and damage. The anti-corrosion coating 9 is applied to the outer wall of the buffer layer 8. It is made of materials with excellent corrosion resistance, including but not limited to fluorocarbon coatings, such as polytetrafluoroethylene (PTFE), polyvinylidene fluoride (PVDF), and other fluorocarbon materials. It has extremely high chemical stability and forms a dense protective film, which can effectively block corrosive media in environments such as acidic gas fields, such as acidic gases and corrosive liquids, preventing the sealing shell 1 from being corroded and improving the sensor's environmental adaptability and working stability under extreme conditions.

[0046] Further optimization of the design involves a chip fixture comprising two symmetrically arranged clamping links 10. Clamping heads 11 are mounted on the opposite end faces of each clamping link 10. The quartz chip 5 is detachably connected between the two clamping heads 11. Two electrode posts are connected to the two clamping links 10 respectively, facilitating the installation and replacement of the quartz chip 5. The clamping links 10 are connected to the electrode posts. When the quartz chip 5 generates thickness shear mode vibration, the electrical signals generated on both sides due to the piezoelectric effect can be quickly and stably transmitted to the electrode posts through the clamping links 10, and then to the external circuit. The symmetrical clamping structure ensures uniform force on the quartz chip 5, guaranteeing stable vibration under pressure and ensuring that the linear relationship between pressure and vibration frequency remains unaffected, thereby improving the accuracy of pressure monitoring.

[0047] The scheme is further optimized. The support structure includes a positioning column 12, a central groove 13 is opened through the center of the positioning column 12, and two mounting grooves 14 are opened on the top surface of the positioning column 12. The two clamping rods 10 are respectively installed in the two mounting grooves 14.

[0048] The bottom surface of the positioning post 12 has two vertical grooves 15 arranged side by side, and the two vertical grooves 15 are respectively connected to two mounting grooves 14; the two electrode posts are installed in the two vertical grooves 15, and a number of second fluororubber O-rings 16 arranged at intervals are installed between the electrode posts and the vertical grooves 15.

[0049] The support structure is centered around the positioning post 12. The mounting groove 14 on its top surface is used to install the clamping rod 10, firmly supporting the chip clamp and ensuring the quartz chip 5 is on the accurate pressure transmission path, allowing the pressure transmitted by the bellows 4 to precisely act on the surface of the quartz chip 5. The vertical groove 15 on the bottom surface of the positioning post 12 is used to install the electrode post, and the vertical groove 15 communicates with the mounting groove 14, providing a channel for the connection between the electrode post and the chip clamp. Several spaced-apart second fluororubber O-rings 16 installed within the vertical groove 15 seal the electrode post, preventing downhole media from entering the sensor through the gap between the electrode post and the vertical groove 15, ensuring the stability and reliability of the connection between the electrode post and the external circuitry. Simultaneously, the central groove 13 of the positioning post 12 can reduce the overall weight of the sensor to some extent without affecting its structural strength and pressure transmission function.

[0050] Further optimization involves creating two through slots 17 on the base 2. The bottoms of the two electrode posts extend through these slots to the bottom of the base 2. The inner diameter of the through slots 17 is smaller than the inner diameter of the vertical slot 15. These through slots connect to the external circuitry, enabling pressure signal output. The smaller inner diameter of the through slots 17 prevents the electrode posts from shaking or shifting during installation and use, ensuring the stability of the connection between the electrode posts and the external circuitry. Furthermore, the cooperation between the through slots 17 and the vertical slot 15, combined with the second fluororubber O-ring seal 16, further enhances the sealing effect on the electrode posts, effectively preventing downhole media from entering the sensor along the electrode posts and ensuring normal sensor operation.

[0051] Further optimizing the design, the quartz chip 5 adopts an AT-cut quartz chip. The unique crystal cutting method of the AT-cut quartz chip gives it excellent frequency-temperature characteristics and mechanical properties. Under pressure, the AT-cut quartz chip can stably generate thickness shear mode vibration, and the resonant frequency of the vibration exhibits a highly linear relationship with the pressure. This stable linear relationship ensures that the sensor can accurately convert pressure changes into frequency changes under different pressure environments. These changes are then transmitted through the electrode posts to the external circuit for processing, ultimately being accurately converted into pressure values, achieving high-precision real-time monitoring of downhole pressure.

[0052] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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. Therefore, they should not be construed as limitations on this utility model.

[0053] Obviously, the above embodiments of this utility model are merely examples for clearly illustrating the present utility model, and are not intended to limit the implementation of the present utility model. For those skilled in the art, other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this utility model should be included within the protection scope of the claims of this utility model.

Claims

1. A downhole quartz resonant pressure sensor, characterized in that, include: A sealed outer shell (1) is provided with a base (2) fixedly installed at the bottom of the sealed outer shell (1); an electromagnetic shielding layer (3) is fixedly provided on the inner wall of the sealed outer shell (1); and a buffer anti-corrosion structure is provided on the outer wall of the sealed outer shell (1). A bellows (4) is installed on the top of the sealing housing (1), and the bottom of the bellows (4) extends into the sealing housing (1); A support structure is mounted on the base (2) and is located inside the sealed housing (1); A chip clamp is mounted on the support structure and is connected to two electrode posts, which extend below the base (2). Quartz chip (5), the quartz chip (5) is mounted on the chip fixture; the bottom of the bellows (4) is in contact with the surface of the quartz chip (5), and the two sides of the quartz chip (5) are respectively connected to the two electrode posts; A sealing structure is installed between the corrugated pipe (4) and the sealing shell (1).

2. The downhole quartz resonant pressure sensor according to claim 1, characterized in that: A through hole (6) is installed through the center of the top of the sealing shell (1), and the bottom of the bellows (4) passes through the through hole (6). The sealing structure includes a first fluororubber O-ring (7), which is fixedly installed on the inner wall of the through hole (6). The inner wall of the through hole (6) and the outer wall of the bellows (4) are both in contact with the first fluororubber O-ring (7).

3. The downhole quartz resonant pressure sensor according to claim 1, characterized in that: The buffer and anti-corrosion structure includes a buffer layer (8) and an anti-corrosion coating (9). The buffer layer (8) is fixedly sleeved on the outer wall of the sealed outer shell (1), and the anti-corrosion coating (9) is disposed on the outer wall of the buffer layer (8).

4. The downhole quartz resonant pressure sensor according to claim 1, characterized in that: The chip fixture includes two symmetrically arranged fixture links (10), and fixture heads (11) are installed on the opposite end faces of the two fixture links (10). The quartz chip (5) is detachably connected between the two fixture heads (11), and the two electrode posts are respectively connected to the two fixture links (10).

5. The downhole quartz resonant pressure sensor according to claim 4, characterized in that: The support structure includes a positioning column (12), a central groove (13) is provided through the center of the positioning column (12), and two mounting grooves (14) are provided on the top surface of the positioning column (12). The two clamping rods (10) are respectively installed in the two mounting grooves (14). The bottom surface of the positioning post (12) has two vertical grooves (15) arranged side by side, and the two vertical grooves (15) are respectively connected to the two mounting grooves (14); the two electrode posts are installed in the two vertical grooves (15), and a number of second fluororubber O-rings (16) are installed between the electrode posts and the vertical grooves (15) at intervals.

6. The downhole quartz resonant pressure sensor according to claim 5, characterized in that: The base (2) has two through slots (17), and the bottoms of the two electrode posts extend through the through slots (17) to the bottom of the base (2). The inner diameter of the through slots (17) is smaller than the inner diameter of the vertical slot (15).

7. The downhole quartz resonant pressure sensor according to claim 1, characterized in that: The quartz chip (5) is an AT-cut quartz chip.

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