A self-cleaning downhole fluid sampling device for ocean engineering

Abstract

The application relates to a self-cleaning downhole fluid sampling device for ocean engineering, and relates to the technical field of ocean engineering, which comprises a sampling cylinder, a sampling assembly, a cleaning assembly, a control adjusting piece, a lifting assembly and a separation piece. A sampling cavity is arranged in the sampling cylinder, a sampling inlet and a sampling outlet are arranged on the sampling cylinder, the sampling assembly is arranged in the sampling cylinder, the sampling assembly is used for downhole sampling, the cleaning assembly is arranged on the sampling cylinder, the cleaning assembly is used for cleaning the sampling cylinder, the control adjusting piece is arranged on the sampling assembly, the control adjusting piece is used for adjusting the running state of the sampling assembly and the cleaning assembly, and the separation piece is arranged on the sampling cylinder and is used for separating impurities in the sample. The application has the effects of improving the precision and efficiency of downhole fluid sampling test.

Description

Technical Field

[0001] This application relates to the technical field of marine engineering, and in particular to a self-cleaning downhole fluid sampling device for marine engineering. Background Technology

[0002] In the field of marine engineering, downhole fluid sampling devices are key equipment for conducting seabed geological exploration, marine resource assessment, and deep-sea environmental monitoring. By obtaining seabed strata fluid samples, information such as seabed pressure field distribution, fluid composition, and corrosive parameters can be accurately analyzed, providing core data support for marine resource development and the protection of seabed engineering facilities.

[0003] Existing marine downhole fluid sampling devices use cables to lower the sampling device to a predetermined seabed location, then open the inlet to allow seabed fluid to enter the sampling tube to complete the sampling process. Afterward, the sampling device is raised to the surface for subsequent testing and analysis of the sample.

[0004] Regarding the aforementioned technologies, due to the unique marine environment, impurities such as silt particles, biological debris, and salt crystals carried by seabed fluids are difficult to effectively filter and isolate during the sampling process, resulting in low sample purity and affecting the accuracy of test results. In addition, after a period of use, dirt and impurities easily accumulate inside the sampling container, lacking an effective self-cleaning function, making cleaning and maintenance cumbersome and time-consuming, and reducing sampling efficiency. Summary of the Invention

[0005] To improve the accuracy and efficiency of downhole fluid sampling and testing, this application provides a self-cleaning downhole fluid sampling device for marine engineering.

[0006] This application provides a self-cleaning downhole fluid sampling device for marine engineering, which adopts the following technical solution: A self-cleaning downhole fluid sampling device for marine engineering, comprising: A sampling tube has a sampling cavity inside, and an inlet and an outlet are provided on the sampling tube. The sampling cavity is connected to both the inlet and the outlet. A sampling assembly, which is installed inside the sampling cylinder, is used for downhole sampling; A cleaning component is mounted on the sampling cylinder and is used to clean the sampling cylinder; A control adjustment component is mounted on the sampling assembly and is used to adjust the operating state of the sampling assembly and the cleaning assembly; An isolation element is installed on the sampling cylinder and is used to isolate impurities in the sample.

[0007] By adopting the above technical solution, during downhole fluid sampling, the downhole fluid flows into the sampling chamber of the sampling tube through the inlet. The sampling component completes the downhole sampling work, while the isolation component effectively isolates impurities in the sample, improving the purity of the collected sample and ensuring the accuracy of subsequent test results. The cleaning component cleans the sampling tube, preventing dirt and impurities from adhering to the inside of the tube. The control and adjustment component can flexibly adjust the operating status of the sampling component and the cleaning component, ensuring that different needs of the device can be met and that it can operate efficiently under different working conditions, thereby improving the efficiency and quality of downhole fluid sampling and testing.

[0008] Optionally, the sampling cylinder is provided with a mounting groove, and the sampling assembly includes: A sampling motor is disposed in the mounting slot, and the fixed end of the sampling motor is fixedly connected to the sampling cylinder; A rotating shaft is rotatably disposed inside the sampling cylinder. One end of the rotating shaft is coaxially and fixedly connected to the output end of the sampling motor. A threaded groove is provided on the rotating shaft, and the rotating shaft is connected to the control adjustment component. A baffle is slidably mounted on the rotating shaft and is adapted to the sample inlet; A filter screen is disposed on the sample inlet.

[0009] By adopting the above technical solution, during the downhole fluid sampling process, the sampling motor drives the rotating shaft to rotate. The rotating shaft is connected to the control and adjustment components, which can precisely adjust the sampling state according to the actual situation. The threaded groove on the rotating shaft, together with the baffle, can flexibly control the position of the baffle and the inlet, realize the opening and closing of the inlet, control the amount and timing of the downhole fluid entering, and the filter screen can initially filter large particulate impurities in the fluid during sampling, improve the purity of the sample entering the sampling tube, provide a more reliable sample for subsequent testing and analysis, and thus improve the accuracy and efficiency of the entire downhole fluid sampling and testing work.

[0010] Optionally, the cleaning component includes: The first gear is rotatably disposed within the mounting slot; A first connecting rod, one end of which is connected to the rotating shaft; The second link has one end hinged to the end of the first link away from the rotation axis, and the other end hinged to the end face of the first gear. Multiple cleaning brushes are arranged circumferentially around the axis of the first gear. Each cleaning brush is fixedly connected to the first gear and abuts against the inner wall of the sampling cylinder.

[0011] By adopting the above technical solution, the rotation of the rotating shaft drives the first connecting rod to move. The first connecting rod transmits the motion to the first gear through the second connecting rod, causing the first gear to reciprocate within the mounting slot. At this time, the rotation of the first gear drives the cleaning brush to clean the inner wall of the sampling cylinder. The operation of the cleaning component is realized by utilizing the power of the rotating shaft, without the need for an additional power source. It can promptly remove dirt and impurities attached to the inner wall of the sampling cylinder, avoiding interference from impurities with subsequent sampling, ensuring the cleanliness of the sampling cylinder, thereby improving the accuracy of sampling and the service life of the device, and reducing the workload and frequency of manual cleaning and maintenance.

[0012] Optionally, the cleaning component further includes: The second gear is rotatably disposed in the mounting groove and meshes with the first gear. A connecting rod, one end of which is fixedly connected to the second gear on the same axis, the other end of which is rotatably mounted on the sampling cylinder, and the middle section of which is located outside the sampling cylinder; A scraper is fixedly installed on the connecting rod and abuts against the filter screen.

[0013] By adopting the above technical solution, when the cleaning component is running, the rotation of the first gear drives the reciprocating rotation of the second gear meshing with it. The rotation of the second gear causes the connecting rod to rotate around its rotation point on the sampling cylinder. The rotation of the connecting rod drives the scraper to scrape and clean the filter screen, realizing automatic cleaning of the filter screen at the inlet. During the sampling process, a large number of impurities will be trapped on the filter screen. If it is not cleaned in time, it will affect the speed and efficiency of the fluid entering the sampling cylinder, and may even cause blockage. The continuous scraping of the scraper can effectively remove the impurities attached to the filter screen, ensure the permeability of the filter screen, and thus ensure that the downhole fluid enters the sampling cylinder smoothly and maintain the normal operation of the sampling work.

[0014] Optionally, the baffle has a mounting cavity, and the control adjustment component includes: A first ratchet is disposed in the mounting cavity and is sleeved on the rotating shaft and is helically connected to the rotating shaft. A first pawl is disposed in the mounting cavity, hinged to the baffle, and adapted to the first ratchet. A first spring, the two ends of which are fixedly connected to the first pawl and the baffle, respectively; The second ratchet is coaxially mounted on the rotating shaft, and the steering effects controlled by the first ratchet and the second ratchet are opposite. The second pawl is hinged to the first connecting rod and is adapted to the second ratchet. The second spring has its two ends fixedly connected to the second pawl and the first connecting rod, respectively.

[0015] By adopting the above technical solution, the control adjustment component can effectively adjust the operating status of the sampling component and the cleaning component. When the sampling motor drives the rotating shaft to rotate forward, the first ratchet is matched with the first ratchet under the action of the first spring, controlling the forward rotation of the first ratchet, thereby controlling the baffle to slide on the rotating shaft, realizing the regulation of the opening and closing state of the inlet, ensuring that the downhole fluid enters the sampling tube at a suitable depth, and improving the sampling accuracy.

[0016] When the sampling motor drives the rotating shaft in reverse, due to the characteristics of the ratchet mechanism, the baffle cannot be controlled by the rotating shaft and remains stationary. Meanwhile, the first connecting rod, in cooperation with the second pawl and the second ratchet, moves, causing the cleaning component to begin cleaning the sampling cylinder. Because the first and second ratchets control opposite directions, the control adjustment component can control the sliding of the baffle and the operation of the cleaning component according to the direction of the rotating shaft's rotation. This allows for switching and adjustment of the rotating shaft between sampling and cleaning functions, making the device more compact and easier to operate.

[0017] Optionally, a lifting assembly is also connected to the sampling cylinder, the lifting assembly comprising: A support frame is installed at the wellhead; A lifting motor, wherein the fixed end of the lifting motor is fixedly mounted on the support frame; A roller is rotatably mounted on the support frame, and the output end of the lifting motor is coaxially and fixedly connected to the roller. A steel wire rope is wound around the drum, and one end of the steel wire rope is fixedly connected to the sampling cylinder.

[0018] By adopting the above technical solution, during the sampling operation, the support frame at the wellhead provides a stable support foundation for the entire lifting assembly. When the lifting motor starts, it drives the drum to rotate. The rotation of the drum can drive the wire rope to be wound and released, thereby realizing the lifting and lowering of the sampling tube in the well. This allows the operator to accurately send the sampling tube to the predetermined well location for sampling according to actual needs, improving the accuracy of the sampling location and reducing labor costs and labor intensity.

[0019] Optionally, the bottom of the sampling cylinder is provided with an impurity chamber, which is connected to the sampling chamber, and a drain cover is threadedly connected to the bottom of the sampling cylinder.

[0020] By adopting the above technical solution, after sampling, impurities will settle into the impurity chamber and be isolated from the sample by the isolation component. When it is necessary to clean the impurities, the staff only needs to unscrew the drain cover at the bottom to discharge the impurities, which facilitates regular maintenance and cleaning and greatly improves the ease of use and maintenance efficiency of the device.

[0021] Optionally, the isolation element includes: An electrically operated telescopic plate is disposed at the communication point between the impurity chamber and the sampling chamber; An airbag is fixedly installed inside the sampling cylinder, and the position of the airbag is adapted to the electric telescopic plate. A telescopic rod is fixedly installed on the sampling cylinder. The rod cavity of the telescopic rod is connected to the air bladder. In the initial state, the movable end of the telescopic rod abuts against the sample outlet. A third spring is disposed within the rodless cavity of the telescopic rod.

[0022] By adopting the above technical solution, the isolation component can effectively separate the sample from the impurities and intelligently control the sample outlet. When impurity isolation is required, the electric telescopic plate can extend and retract at the connection between the impurity chamber and the sampling chamber. During the sampling process, the electric telescopic plate is in the open state, and the sampling chamber is connected to the impurity chamber, allowing the impurities to precipitate into the impurity chamber.

[0023] When the electric telescopic plate moves, it compresses the airbag. Initially, the movable end of the telescopic rod, under the action of the third spring, abuts against the sample outlet. When sampling is complete and the sample needs to be poured out, the electric telescopic plate opens, the airbag is compressed, the pressure inside the telescopic rod increases, and the telescopic rod retracts against the elastic force of the third spring, opening the sample outlet and allowing the sample to flow out of the sampling tube for testing. When the airbag pressure is released, the movable end of the telescopic rod, under the action of the third spring, will abut against the sample outlet again, closing the sample outlet. This allows the isolation component to not only effectively isolate impurities but also automatically control the opening and closing of the sample outlet according to different stages of sampling and dispensing, realizing intelligent operation of the device and improving work efficiency.

[0024] Optionally, a counterweight is fixedly installed at the bottom of the drain cover.

[0025] By adopting the above technical solution, the counterweight increases the overall weight of the sampling tube during its descent, enabling it to overcome interference factors such as water flow resistance in the downhole fluid environment and descend more smoothly to the predetermined sampling position. At the same time, it ensures that the sampling tube remains vertical during descent, guaranteeing that impurities will settle smoothly into the impurity chamber at the bottom of the sampling tube under the action of gravity. This avoids the inability of impurities to settle effectively or uneven distribution within the sampling tube due to the tilt of the sampling tube, which would affect sample collection and subsequent testing and analysis.

[0026] Optionally, the filter screen has an arc-shaped structure, and the axis of the filter screen coincides with the axis of the second gear.

[0027] By adopting the above technical solution, when the cleaning component is working, the second gear drives the scraper to rotate, and the scraper can scrape and clean the arc-shaped filter screen more closely, effectively removing impurities attached to the filter screen, reducing impurity residue, preventing filter screen blockage due to impurity accumulation, and ensuring that the filter screen maintains good filtration performance.

[0028] In summary, this application includes at least one of the following beneficial technical effects: By incorporating cleaning components, residual fluids or impurities on the inner wall of the sampling tube can be effectively removed, preventing cross-contamination of samples caused by deposits on the inner wall and significantly improving the accuracy of sampling results. The design of the isolation element can effectively prevent impurities in the sample from entering the sampling chamber, ensuring the purity of the collected fluid sample and thus improving the reliability of the analytical data; The control and adjustment components work together with the sampling components to achieve precise control of the sampling and cleaning process, adapt to complex downhole environments, and improve the automation level and ease of operation of the device. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the structure of the fluid sampling device according to an embodiment of this application; Figure 2 This is a cross-sectional view of the sampling cylinder in an embodiment of this application; Figure 3 This is an embodiment of the present application. Figure 2 A magnified view of part A; Figure 4 This is a cross-sectional view of the sampling component, as shown in this embodiment of the application. Figure 5 This is a cross-sectional view of an embodiment of the present application for illustrating the control adjustment component; Figure 6 This is an embodiment of the present application. Figure 5 A magnified view of section B; Figure 7 This application is a cross-sectional view for illustrating the cleaning components; Figure 8 This is an embodiment of the present application. Figure 7 A magnified view of a portion of point C.

[0030] Explanation of reference numerals in the attached figures: 1. Sampling cylinder; 11. Sampling chamber; 12. Inlet; 13. Outlet; 14. Mounting slot; 15. Impurity chamber; 2. Sampling assembly; 21. Sampling motor; 22. Rotating shaft; 221. Threaded groove; 23. Baffle; 231. Mounting chamber; 24. Filter screen; 3. Cleaning assembly; 31. First gear; 32. First connecting rod; 33. Second connecting rod; 34. Cleaning brush; 35. Second gear; 36. Connecting rod; 37. Scraper; 4. Control and adjustment components; 41. First ratchet; 42. First pawl; 43. First spring; 44. Second ratchet; 45. Second pawl; 46. Second spring; 5. Isolator; 51. Electric telescopic plate; 52. Airbag; 53. Telescopic rod; 54. Third spring; 6. Lifting assembly; 61. Support frame; 62. Lifting motor; 63. Roller; 64. Wire rope; 7. Sewage cover; 8. Counterweight. Detailed Implementation

[0031] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0032] The following is in conjunction with the appendix Figure 1-8 This application will be described in further detail.

[0033] This application discloses a self-cleaning downhole fluid sampling device for marine engineering.

[0034] Reference Figure 1 , Figure 2 and Figure 3 A self-cleaning downhole fluid sampling device for marine engineering includes a sampling cylinder 1, a sampling assembly 2, a cleaning assembly 3, a control and adjustment component 4, a lifting assembly 6, and an isolation component 5. The sampling cylinder 1 has a sampling chamber 11 inside, and an inlet 12 and an outlet 13 on its surface. The sampling assembly 2 is installed inside the sampling cylinder 1 and is used for downhole sampling. The cleaning assembly 3 is installed on the sampling cylinder 1 and is used for cleaning it. The control and adjustment component 4 is installed on the sampling assembly 2 and is used to adjust the operating status of the sampling assembly 2 and the cleaning assembly 3. The isolation component 5 is installed on the sampling cylinder 1 and is used to isolate impurities in the sample.

[0035] When using this self-cleaning downhole fluid sampling device for marine engineering, the sampling cylinder 1 is first lowered to a predetermined position in the well via the lifting assembly 6. Then, the sampling assembly 2 is activated, and the opening and closing of the inlet 12 is controlled by the control adjustment component 4. The downhole fluid is initially filtered by the filter screen 24 at the inlet 12 before flowing into the sampling chamber 11 of the sampling cylinder 1. During sampling, the cleaning assembly 3 can be activated to clean the inner wall of the sampling cylinder 1 and the filter screen 24 at the inlet 12. After the sampling assembly 2 completes the downhole sampling, impurities in the sampling cylinder 1 settle. These impurities can be isolated by the isolation component 5, opening the outlet 13, allowing the fluid to flow out for testing and analysis. After sampling is completed, the cleaning assembly 3 can also be activated to clean the entire sampling cylinder 1, improving the accuracy and efficiency of downhole fluid sampling and testing.

[0036] Reference Figure 1 and Figure 2 The sampling cylinder 1 is cylindrical with a hollow interior forming a sampling chamber 11. The inlet 12 is located on the side wall of the sampling cylinder 1 and communicates with the sampling chamber 11. The outlet 13 is also located on the side wall of the sampling cylinder 1 and communicates with the sampling chamber 11. An impurity chamber 15 is located at the bottom of the sampling cylinder 1 and communicates with the sampling chamber 11. A drain cover 7 is threadedly connected to the bottom of the sampling cylinder 1, and a counterweight 8 is fixedly installed at the bottom of the drain cover 7.

[0037] Reference Figure 1 The lifting assembly 6 includes a support frame 61, a lifting motor 62, a drum 63, and a wire rope 64. The support frame 61 is located at the wellhead. The fixed end of the lifting motor 62 is fixedly mounted on the support frame 61. The drum 63 is rotatably mounted on the support frame 61. The output end of the lifting motor 62 is coaxially and fixedly connected to the drum 63. The wire rope 64 is wound around the drum 63, and one end of the wire rope 64 is fixedly connected to the sampling cylinder 1.

[0038] Before sampling, the support frame 61 is securely set at the wellhead. When the sampling cylinder 1 needs to be lowered into the well, the lifting motor 62 controls the drum 63 to rotate forward, causing the steel wire rope 64 wound on the drum 63 to gradually unwind. Under its own weight and the traction of the steel wire rope 64, the sampling cylinder 1 descends to the predetermined sampling position in the well. After completing the sampling operation in the well, the sampling cylinder 1 needs to be lifted to the surface. At this time, the lifting motor 62 controls the drum 63 to rotate in the reverse direction and begins to wind up the steel wire rope 64. As the steel wire rope 64 is gradually wound around the drum 63, the sampling cylinder 1 is pulled upward and finally lifted to the wellhead, facilitating subsequent testing and analysis of the sample by the staff and reducing the difficulty and labor intensity of manual operation.

[0039] Reference Figure 2 and Figure 4The sampling assembly 2 includes a sampling motor 21, a rotating shaft 22, a baffle 23, and a filter screen 24. A mounting groove 14 is provided on the sampling cylinder 1, and the sampling motor 21 is installed in the mounting groove 14. The fixed end of the sampling motor 21 is fixedly connected to the sampling cylinder 1. The rotating shaft 22 is vertically arranged and rotatably installed inside the sampling cylinder 1. One end of the rotating shaft 22 is coaxially fixedly connected to the output end of the sampling motor 21. A threaded groove 221 is provided on the rotating shaft 22, and the rotating shaft 22 is connected to the control adjustment component 4. The baffle 23 is slidably installed on the rotating shaft 22 and is adapted to the sample inlet 12. The filter screen 24 has an arc-shaped structure and is installed on the sample inlet 12.

[0040] Initially, baffle 23 is positioned at the inlet 12 to prevent downhole fluid from flowing in. When the device reaches the predetermined downhole position, the sampling motor 21 is activated, driving the rotating shaft 22 to rotate. The threaded groove 221 on the rotating shaft 22 works in conjunction with the control adjustment component 4, driving the baffle 23 to slide on the rotating shaft 22 via the threaded groove 221. When the baffle 23 slides to open the inlet 12, downhole fluid begins to flow in. During this process, the filter screen 24 at the inlet 12 functions, performing preliminary filtration of large particulate impurities in the fluid, improving the purity of the fluid flowing into the sampling cylinder 1. After sampling is completed, the sampling motor 21 is activated again, controlling the baffle 23 to slide again via the threaded groove 221 until the inlet 12 is closed, completing a precise downhole sampling operation.

[0041] Reference Figure 4 , Figure 5 and Figure 7 The cleaning assembly 3 includes a first gear 31, a first connecting rod 32, a second connecting rod 33, four cleaning brushes 34, a second gear 35, a connecting rod 36, and a scraper 37. The first gear 31 is horizontally arranged and rotatably installed in the mounting groove 14. The lower end face of the first gear 31 abuts against the sampling cylinder 1. One end of the first connecting rod 32 is connected to the rotating shaft 22. One end of the second connecting rod 33 is hinged to the end of the first connecting rod 32 away from the rotating shaft 22. The other end of the second connecting rod 33 is hinged to the end face of the first gear 31. The four cleaning brushes 34 are arranged circumferentially around the axis of the first gear 31. All cleaning brushes 34 are fixedly connected to the first gear 31 and abut against the inner wall of the sampling cylinder 1.

[0042] Reference Figure 5 and Figure 7The second gear 35 is rotatably mounted in the mounting groove 14 and meshes with the first gear 31. The connecting rod 36 has a C-shaped cross section. One end of the connecting rod 36 is coaxially and fixedly connected to the second gear 35, and the other end of the connecting rod 36 is rotatably mounted on the sampling cylinder 1. The middle section of the connecting rod 36 is located outside the sampling cylinder 1. A groove is opened on the sampling cylinder 1 so that the connecting rod 36 can rotate with the second gear 35. The axis of the filter screen 24 coincides with the axis of the second gear 35. The scraper 37 is fixedly mounted on the connecting rod 36 and abuts against the filter screen 24.

[0043] When the sampling cylinder 1 needs to be cleaned, the sampling motor 21 drives the rotating shaft 22 to rotate in the opposite direction. When the rotating shaft 22 rotates, it will drive the first connecting rod 32 to move. The first connecting rod 32 transmits the motion to the first gear 31 through the second connecting rod 33 that is hinged to it, so that the first gear 31 rotates back and forth. During the rotation, the cleaning brush 34 thoroughly cleans the inner wall of the sampling cylinder 1, removing the dirt and impurities attached to the inner wall of the sampling cylinder 1.

[0044] At the same time, the second gear 35, which meshes with the first gear 31, also begins to rotate. The rotation of the second gear 35 drives the connecting rod 36 to rotate around the axis of the second gear 35. The connecting rod 36 rotates with the second gear 35 through the groove opened on the sampling cylinder 1. The scraper 37 continuously abuts against and scrapes the filter screen 24, effectively removing the impurities trapped on the filter screen 24, ensuring the permeability of the filter screen 24, and allowing the downhole fluid to pass smoothly during subsequent sampling. The cleaning component 3 achieves a comprehensive cleaning of the inner wall of the sampling cylinder 1 and the filter screen 24, creating favorable conditions for the next sampling operation.

[0045] Reference Figure 5 , Figure 6 , Figure 7 and Figure 8 The control adjustment component 4 includes a first ratchet 41, a first pawl 42, a first spring 43, a second ratchet 44, a second pawl 45, and a second spring 46. A mounting cavity 231 is provided on the baffle 23. The first ratchet 41 is disposed within the mounting cavity 231 and is sleeved on the rotating shaft 22, and is helically connected to the rotating shaft 22 via a threaded groove 221. The upper and lower end faces of the first ratchet 41 abut against the baffle 23. The first pawl 42 is disposed within the mounting cavity 231 and is hinged to the baffle 23. The first pawl 42 is adapted to the first ratchet 41. Both ends of the first spring 43 are fixedly connected to the first pawl 42 and the baffle 23, respectively.

[0046] Reference Figure 7 and Figure 8The second ratchet 44 is coaxially sleeved and fixedly installed on the rotating shaft 22. The steering effect controlled by the first ratchet 41 and the second ratchet 44 is opposite. The second pawl 45 is hinged to the first link 32 and is adapted to the second ratchet 44. The two ends of the second spring 46 are fixedly connected to the second pawl 45 and the first link 32 respectively.

[0047] When the sampling motor 21 is started, and the sampling motor 21 drives the rotating shaft 22 to rotate in the reverse direction, the first ratchet 41 of the rotating shaft 22 rotates, and the first pawl 42 is moved by the first ratchet 41, causing the first ratchet 41 to spin freely. When the sampling motor 21 drives the rotating shaft 22 to rotate in the forward direction, the first pawl 42 will abut against the first ratchet 41 under the action of the first spring 43, causing the first ratchet 41 to move with the baffle 23. Since the first ratchet 41 is connected to the rotating shaft 22 by a helical transmission, the first ratchet 41 moves along the rotating shaft 22. The upward movement tends to generate axial motion, which allows the first ratchet 41 to drive the baffle 23 to slide on the rotating shaft 22. The threaded groove 221 of the rotating shaft 22 can drive the first ratchet 41 to move up and down reciprocally, thereby opening the inlet 12 and allowing the downhole fluid to flow into the sampling cylinder 1 for sampling. When the rotating shaft 22 continues to rotate in the positive direction, the first ratchet 41 controls the baffle 23 to rise, precisely controlling the opening and closing degree of the inlet 12 to ensure that an appropriate amount of downhole fluid enters the sampling cylinder 1 and completes the accurate sampling operation.

[0048] When the device needs to be cleaned, the sampling motor 21 drives the rotating shaft 22 to rotate in the opposite direction. Since the first ratchet 41 and the second ratchet 44 control opposite directions, the second pawl 45 will abut against the second ratchet 44 under the action of the second spring 46, so that the first connecting rod 32 and the first ratchet 41 rotate synchronously, thereby driving the cleaning component 3 to clean the sampling cylinder 1. When the sampling motor 21 drives the rotating shaft 22 to rotate in the forward direction, the second pawl 45 is moved by the second ratchet 44, so that the second ratchet 44 spins freely, stopping the cleaning function. The control adjustment component 4 uses the characteristics of the ratchet mechanism to accurately switch between the sampling and cleaning states through the same drive source, ensuring the efficient and orderly operation of the device.

[0049] Reference Figure 2 and Figure 3The isolation component 5 includes an electric telescopic plate 51, an airbag 52, a telescopic rod 53, and a third spring 54. The electric telescopic plate 51 is located at the connection between the impurity chamber 15 and the sampling chamber 11. The airbag 52 is fixedly installed inside the sampling cylinder 1, and its position is adapted to the electric telescopic plate 51. The airbag 52 and the electric telescopic plate 51 are located on the same horizontal plane. When the electric telescopic plate 51 extends, one end of the electric telescopic plate 51 squeezes the airbag 52. The telescopic rod 53 is vertically set and fixedly installed on the sampling cylinder 1. The rod-side chamber of the telescopic rod 53 is connected to the airbag 52 through a pipe. In the initial state, the movable end of the telescopic rod 53 abuts against the sample outlet 13. The third spring 54 is located in the rodless chamber of the telescopic rod 53.

[0050] During device operation, in the initial state, the movable end of the telescopic rod 53 is closed by the action of the third spring 54 against the sample outlet 13. At this time, the electric telescopic plate 51 retracts, and the impurity chamber 15 is connected to the sampling chamber 11. After the downhole fluid flows into the sampling chamber 11, the impurities settle into the impurity chamber 15. The capacity of the impurity chamber 15 can be adaptively adjusted according to the sample. When the impurity content in the sample is high, a larger impurity chamber 15 can be set to meet the storage requirements of high impurity samples, so that all the impurities in the sample can enter the impurity chamber 15 during the sedimentation process. When sampling is completed and the sample needs to be discharged... The operator controls the extension of the electric telescopic plate 51 to separate the sampling chamber 11 from the impurity chamber 15. When the movable end of the electric telescopic plate 51 extends, it will squeeze the air bladder 52 until the electric telescopic plate 51 extends to its longest position. The gas in the air bladder 52 enters the rod chamber of the telescopic rod 53 through the pipe, overcoming the elastic force of the third spring 54 and causing the movable end of the telescopic rod 53 to retract, opening the sample outlet 13 to allow the sample to flow out. After the sample is discharged, the operator controls the electric telescopic plate 51 to retract, the air bladder 52 returns to its original position, and the movable end of the telescopic rod 53, under the action of the third spring 54, abuts against the sample outlet 13 again to close the outlet, waiting for the next sampling.

[0051] The implementation principle of a self-cleaning downhole fluid sampling device for marine engineering according to an embodiment of this application is as follows: First, the lifting assembly 6 is used to drive the drum 63 to rotate through the lifting motor 62 to realize the winding and unwinding of the wire rope 64, and the sampling cylinder 1 is accurately lowered to the predetermined position downhole. Then, the sampling assembly 2 works, the sampling motor 21 is started to drive the rotating shaft 22 to rotate forward, and under the action of the control adjustment component 4, the baffle 23 is driven to slide through the threaded groove 221 to open the sampling port 12. The downhole fluid flows into the sampling chamber 11 after being initially filtered by the filter screen 24 to complete the sampling, and then the sampling port 12 is closed.

[0052] During or after sampling, a cleaning operation can be performed. When the rotating shaft 22 rotates in the reverse direction, the second pawl 45 in the control adjustment component 4 abuts against the second ratchet 44, driving the cleaning component 3. The first gear 31 drives the cleaning brush 34 to clean the inner wall of the sampling cylinder 1, and the second gear 35 meshing with it drives the scraper 37 to clean the filter screen 24, ensuring the device is clean.

[0053] After sampling, impurities settle in impurity chamber 15, and the isolator 5 takes effect. Initially, the electric telescopic plate 51 retracts, connecting impurity chamber 15 with sampling chamber 11, and the sample outlet 13 is closed. When a sample needs to be discharged, the electric telescopic plate 51 extends to separate the two chambers and squeezes the air bladder 52, causing the movable end of the telescopic rod 53 to retract and open the sample outlet 13. After the sample flows out, the electric telescopic plate 51 retracts, and the sample outlet 13 is closed.

[0054] In addition, the control adjustment component 4, through the characteristics of the ratchet mechanism, uses the same driving source sampling motor 21 to achieve precise switching between sampling and cleaning states. The counterweight 8 at the bottom of the drain cover 7 assists the sampling cylinder 1 to descend smoothly and remain vertical, facilitating the sedimentation of impurities. Through the coordinated work of various components, efficient and accurate downhole fluid sampling and testing is achieved, improving work accuracy and efficiency.

[0055] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A self-cleaning downhole fluid sampling device for marine engineering, characterized in that, include: A sampling tube (1) is provided inside the sampling tube (1). The sampling tube (1) is provided with an inlet (12) and an outlet (13). The sampling tube (1) is connected to both the inlet (12) and the outlet (13). An impurity chamber (15) is provided at the bottom of the sampling tube (1). The impurity chamber (15) is connected to the sampling tube (11). Sampling assembly (2), which is installed inside the sampling cylinder (1) and is used for downhole sampling; the sampling assembly (2) includes a sampling motor (21) and a rotating shaft (22) connected to the output end of the sampling motor (21). A cleaning component (3) is installed on the sampling cylinder (1) and is used to clean the sampling cylinder (1). A control adjustment component (4) is installed on the sampling assembly (2). The control adjustment component (4) includes a first ratchet (41), a first pawl (42), a second ratchet (44), and a second pawl (45), and is used to adjust the operating state of the sampling assembly (2) and the cleaning assembly (3) according to the forward and reverse rotation of the sampling motor (21). The isolation element (5) is installed on the sampling cylinder (1). The isolation element (5) includes an electric telescopic plate (51), an air bladder (52), a telescopic rod (53), and a third spring (54). The electric telescopic plate (51) extends to separate the sampling chamber (11) from the impurity chamber (15), and in conjunction with this action, it squeezes the air bladder (52). The telescopic rod (53) is then driven to retract by the air pressure, thereby automatically opening the sample outlet (13).

2. The self-cleaning downhole fluid sampling device for marine engineering according to claim 1, characterized in that, The sampling cylinder (1) is provided with an installation groove (14), and the sampling motor (21) is installed in the installation groove (14). The fixed end of the sampling motor (21) is fixedly connected to the sampling cylinder (1). The rotating shaft (22) is rotatably disposed inside the sampling cylinder (1), and a threaded groove (221) is provided on the rotating shaft (22). The rotating shaft (22) is connected to the control adjustment component (4). A baffle (23) is slidably mounted on the rotating shaft (22) and is adapted to the injection port (12); A filter screen (24) is disposed on the inlet (12).

3. The self-cleaning downhole fluid sampling device for marine engineering according to claim 2, characterized in that, The cleaning component (3) includes: The first gear (31) is rotatably disposed in the mounting groove (14); The first connecting rod (32) has one end connected to the rotating shaft (22); The second link (33) has one end hinged to the end of the first link (32) away from the rotating shaft (22), and the other end of the second link (33) is hinged to the end face of the first gear (31). Multiple cleaning brushes (34) are arranged circumferentially around the axis of the first gear (31). The cleaning brushes (34) are all fixedly connected to the first gear (31) and abut against the inner wall of the sampling cylinder (1).

4. The self-cleaning downhole fluid sampling device for marine engineering according to claim 3, characterized in that, The cleaning component (3) also includes: The second gear (35) is rotatably disposed in the mounting groove (14) and meshes with the first gear (31); A connecting rod (36) is provided, one end of which is coaxially and fixedly connected to the second gear (35), the other end of which is rotatably mounted on the sampling cylinder (1), and the middle section of which is located outside the sampling cylinder (1). The scraper (37) is fixedly installed on the connecting rod (36) and abuts against the filter screen (24).

5. The self-cleaning downhole fluid sampling device for marine engineering according to claim 4, characterized in that, The baffle (23) has an installation cavity (231), the first ratchet (41) is disposed in the installation cavity (231), and the first ratchet (41) is sleeved on the rotating shaft (22) and is connected to the rotating shaft (22) by a helical drive. The first pawl (42) is disposed in the mounting cavity (231), the first pawl (42) is hinged to the baffle (23), and the first pawl (42) is adapted to the first ratchet (41); The first spring (43) has its two ends fixedly connected to the first pawl (42) and the baffle (23), respectively. The second ratchet (44) is coaxially mounted on the rotating shaft (22), and the first ratchet (41) and the second ratchet (44) control the opposite steering effect; The second pawl (45) is hinged to the first connecting rod (32), and the second pawl (45) is adapted to the second ratchet (44); The second spring (46) has its two ends fixedly connected to the second pawl (45) and the first connecting rod (32), respectively.

6. The self-cleaning downhole fluid sampling device for marine engineering according to claim 1, characterized in that, The sampling cylinder (1) is also connected to a lifting assembly (6), which includes: A support frame (61) is provided at the wellhead; A lifting motor (62) is provided, the fixed end of which is fixedly mounted on the support frame (61); The roller (63) is rotatably mounted on the support frame (61), and the output end of the lifting motor (62) is coaxially and fixedly connected to the roller (63); A wire rope (64) is wound around the drum (63), and one end of the wire rope (64) is fixedly connected to the sampling cylinder (1).

7. The self-cleaning downhole fluid sampling device for marine engineering according to claim 1, characterized in that, The bottom of the sampling cylinder (1) is threaded with a drain cover (7).

8. The self-cleaning downhole fluid sampling device for marine engineering according to claim 7, characterized in that, The electric telescopic plate (51) is located at the connection between the impurity chamber (15) and the sampling chamber (11); The airbag (52) is fixedly installed inside the sampling tube (1), and the position of the airbag (52) is adapted to the electric telescopic plate (51); The telescopic rod (53) is fixedly installed on the sampling tube (1). The rod cavity of the telescopic rod (53) is connected to the air bag (52). In the initial state, the movable end of the telescopic rod (53) abuts against the sample outlet (13). The third spring (54) is disposed in the rodless cavity of the telescopic rod (53).

9. The self-cleaning downhole fluid sampling device for marine engineering according to claim 7, characterized in that, A counterweight (8) is fixedly installed at the bottom of the drain cover (7).

10. The self-cleaning downhole fluid sampling device for marine engineering according to claim 4, characterized in that, The filter screen (24) has an arc-shaped structure, and the axis of the filter screen (24) coincides with the axis of the second gear (35).

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