Device for detecting air tightness of packer and detection method thereof

Abstract

The present application belongs to the technical field of packer detection, and relates to a detection method for the air tightness of a packer. The detection device for the air tightness of the packer comprises a pipeline unit, a bubble measurement unit, a leakage measurement unit, an air pressure detection unit, a unit to be detected, and a controller. The bubble recognition result is obtained through cross verification of the acquired visual data and infrared data signals. If the bubble recognition result meets the grade determination condition, the unit to be detected is determined to be of V0 grade. If the bubble recognition result does not meet the grade determination condition, the leakage measurement step is executed. In the first aspect, the visual form verification and infrared signal positioning are cross verified in coordination, and the micro bubbles are recognized in a targeted manner through the reinforced linkage mode, which is beneficial to improving the accuracy of recognizing effective bubbles. In the second aspect, the volume of the measuring cylinder is coarsely adjusted and finely adjusted through the synergistic cooperation of the macroscopic and microscopic control components, which is beneficial to improving the accuracy of calculating the gas leakage.

Description

Technical Field

[0001] This invention relates to the technical field of packer testing, and more particularly to a packer gas-tightness testing device and method. Background Technology

[0002] In the oil and gas field development sector, packers are core sealing components for downhole stratified production, water injection, and fracturing operations. Their gas-tight performance directly determines the safe production efficiency and wellbore integrity of oil and gas wells. If a packer fails to seal, it can easily lead to risks such as inter-layer flow, abnormal wellhead pressure, and natural gas leakage, and may even cause a blowout. Therefore, before a packer is run into the well, its gas-tight performance must be rigorously verified using surface testing equipment to simulate downhole high-pressure and high-temperature conditions, ensuring that it meets industry V0 and V1 standards.

[0003] However, current methods for testing gas tightness performance have significant shortcomings in practical applications. Many traditional methods are often limited to surface observation of leakage phenomena, lacking in-depth capture of the dynamic changes in the leakage process, especially making it difficult to accurately identify subtle leaks in complex environments. This limitation often results in incomplete test results, easily overlooking potential risks and thus affecting the stability of equipment operation.

[0004] A deeper technical challenge lies in achieving precise quantification of leakage and identification of microbubbles. First, leakage measurement requires extremely high accuracy because even minute volume changes can reflect significant problems in the equipment's sealing performance. However, current technologies often struggle to balance large-scale adjustments with fine-tuning in volume control. Second, identifying microbubbles using only a single perspective is insufficient for comprehensive coverage. For example, microbubbles may be undetectable due to their blurred shape when using a visual camera alone, and weak signals may be difficult to identify when using an infrared sensor alone. These factors lead to inaccurate detection results. Summary of the Invention

[0005] The purpose of this invention is to provide a packer gas-tightness testing device, which aims to solve the technical problems of low accuracy and difficulty in detecting tiny air bubbles in existing testing devices.

[0006] To solve the above technical problems, a packer gas tightness performance testing device is provided, comprising:

[0007] Piping unit;

[0008] The bubble measurement unit includes a visual camera for acquiring visual data and an infrared sensing module for acquiring infrared data.

[0009] The leakage measurement unit includes a measuring cylinder, a macro-control component, and a micro-control component. The macro-control component is connected to the measuring cylinder, and the micro-control component finely adjusts the volume of the measuring cylinder.

[0010] The air pressure detection unit includes a first air pressure sensor and a second air pressure sensor. The first air pressure sensor collects the first air pressure value inside the measuring cylinder in real time, and the second air pressure sensor collects the second air pressure value of the atmospheric environment.

[0011] The test unit is used to hold the test piece, and the test unit is connected to the bubble measuring unit and the leakage measuring unit respectively through the pipeline unit;

[0012] The controller is electrically connected to the vision camera, the infrared sensing module, the macro-control component, the micro-control component, the first air pressure sensor, and the second air pressure sensor, respectively.

[0013] The controller is configured to: apply target pressure and target temperature to the test component in the test unit, obtain bubble identification results based on cross-validation of acquired visual data and infrared data, and determine the test component as V0 level if the bubble identification results meet the level determination conditions; if the bubble identification results do not meet the level determination conditions, then perform the leakage measurement step.

[0014] The leakage measurement step includes:

[0015] The pressure difference is calculated using the first and second air pressure values, and the macro-control component is used to adjust the position of the measuring cylinder so that the pressure difference is within the first pressure difference range.

[0016] The micro-adjustment component is controlled to fine-tune the volume of the measuring cylinder so that the pressure difference value is within the second pressure difference range;

[0017] Calculate the amount of gas leakage per unit time. If the amount of gas leakage is less than the leakage threshold, the test item is determined to be of level V1; otherwise, the test item is determined to be unqualified.

[0018] Furthermore, the packer gas tightness performance testing device also includes a housing, the housing including a water collection space, the measuring cylinder being disposed within the water collection space, and the macro-control component including a mounting frame, a drive motor, a lead screw, a mounting block, a mounting plate, a spiral guide tube, and a guide rod. The mounting frame is fixedly installed in the housing, the drive motor is fixedly installed in the mounting frame and connected to the lead screw, the lead screw being connected to the spiral guide tube, the mounting block and the mounting plate being respectively connected to both ends of the spiral guide tube, and the mounting block being connected to the measuring cylinder. The two ends of the guide rod are respectively connected to the mounting block and the mounting plate.

[0019] Furthermore, a fine-tuning channel for placing the micro-control component is formed on the mounting block. The fine-tuning channel is connected to the water collection space. The micro-control component includes a micro-volume compensation module and a piston. The micro-volume compensation module is connected to the piston, and the micro-volume compensation module is located on the side of the piston away from the water collection space. The fine-tuning channel is sealed by the piston, and the micro-volume compensation module drives the piston to move within the fine-tuning channel.

[0020] Furthermore, the macro-control component also includes a first displacement sensor for acquiring the displacement of the measuring cylinder, and the micro-control component also includes a second displacement sensor for acquiring the displacement of the piston.

[0021] Furthermore, the pipeline unit includes an air path, a first control valve, and a second control valve. The first control valve is used to control the connection between the water collection space and the unit under test, and the second control valve is used to control the connection between the unit under test and the measuring cylinder. The unit under test is externally connected to a pressurization system.

[0022] A method for testing the gas-tightness performance of a packer, applied to the aforementioned packer gas-tightness performance testing device, the method comprising:

[0023] S1. Place the test piece into the test unit and seal the test unit;

[0024] S2. Apply target pressure and target temperature to the test piece in the test unit and perform a setting and sealing operation on the test piece;

[0025] S3. The bubble recognition result is obtained by cross-validation of the acquired visual data and infrared data.

[0026] S4. If the bubble identification result meets the level determination criteria, the test item is determined to be of level V0; if the bubble identification result does not meet the level determination criteria, the leakage measurement step is executed.

[0027] The leakage measurement step includes:

[0028] S41. Calculate the pressure difference value using the first air pressure value and the second air pressure value, and control the macro-control component to adjust the position of the measuring cylinder so that the pressure difference value is within the first pressure difference range;

[0029] S42. Control the micro-adjustment component to fine-tune the volume of the measuring cylinder so that the pressure difference value is within the second pressure difference range;

[0030] S43. Calculate the gas leakage amount per unit time. If the gas leakage amount is less than the leakage threshold, the test piece is determined to be of level V1; otherwise, the test piece is determined to be unqualified.

[0031] Furthermore, the step of obtaining the bubble recognition result through cross-validation of the acquired visual data and infrared data includes:

[0032] The visual camera acquires images of the bubble detection area in real time, performs binarization on the images, extracts the bubble contours, and performs feature matching to obtain real-time visual judgment results.

[0033] The infrared sensing module continuously emits near-infrared light into the bubble detection area, and the receiving end collects the real-time signal strength. If the real-time signal strength is less than the first signal threshold, it sends a suspected bubble infrared signal to the controller.

[0034] The controller retrieves the visual judgment results at the same timestamp. If the visual judgment result indicates that a bubble is suspected to exist, then the existence of a valid bubble is confirmed, and the timestamp of the valid bubble is recorded.

[0035] Furthermore, if the real-time signal strength acquired by the infrared sensing module is less than the second signal threshold, and the attenuation duration of the real-time signal exceeds a preset threshold time, the controller emits a low-intensity infrared suspected signal and activates the enhanced linkage mode; or, if the image analysis result of the visual camera indicates the presence of a blurred outline, the controller emits a visual suspected signal and activates the enhanced linkage mode.

[0036] The enhanced linkage mode includes:

[0037] Obtain the location coordinates of the suspected low-intensity infrared signal.

[0038] The visual camera is subjected to at least one of the following operations: extending the exposure time, increasing the sampling density, enhancing noise reduction, applying polarization filtering, increasing the amount of light entering the position coordinate region, and focusing on the position coordinate region.

[0039] The infrared sensing module shall be subjected to at least one of the following operations: optimizing the signal trigger threshold, increasing the sampling frequency, and improving the spatial mapping accuracy.

[0040] Further, if the bubble identification result meets the level determination criteria, the component to be tested is determined to be at level V0; if the bubble identification result does not meet the level determination criteria, the leakage measurement step includes:

[0041] If no valid bubbles appear within the first preset time after the start of the test, the test piece is determined to be of grade V0.

[0042] If a valid bubble appears within the first preset time after the start of the test, the test time is automatically extended. The timer starts from the time when the first valid bubble appears and waits for the second bubble. If the interval between the second valid bubble and the first valid bubble is greater than the second preset time, the test item is determined to be of level V0. If the interval between the second valid bubble and the first valid bubble is less than the second preset time, the leakage measurement step is executed.

[0043] Furthermore, the formula for calculating the gas leakage amount is as follows:

[0044]

[0045] In the formula:

[0046] This indicates the cross-sectional area of ​​the inner cavity of the measuring cylinder;

[0047] This indicates the displacement of the measuring cylinder from the start to the end of the leakage detection process;

[0048] This represents the cross-sectional area of ​​the fine-tuning channel;

[0049] This indicates the piston displacement from the start to the end of the leak detection.

[0050] Implementing the embodiments of the present invention will have the following beneficial effects:

[0051] The packer gas-tightness testing device and method provided in this embodiment have the following aspects: First, during bubble detection, the visual camera and infrared sensing module work together to acquire visual images of bubbles, confirm bubble formation using near-infrared light, and perform dual-signal cross-verification through visual morphology verification and infrared signal positioning. Furthermore, a strengthened linkage mode is used to specifically identify microbubbles, which helps improve the accuracy of identifying effective bubbles. Second, through the coordinated operation of macro-control and micro-control components, when calculating gas leakage, the macro-control component is first used to quickly and coarsely adjust the volume of the measuring cylinder, and then the micro-control component is used to finely adjust the volume of the measuring cylinder, making the gas pressure inside the measuring cylinder equal to the gas pressure in the water collection space, which helps improve the accuracy of calculating gas leakage. Attached Figure Description

[0052] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0053] Figure 1 This is a top view of the packer gas tightness testing device according to an embodiment of the present invention;

[0054] Figure 2 This is a schematic diagram of the packer gas tightness performance testing device after removing the infrared sensing module according to an embodiment of the present invention;

[0055] Figure 3 This is a cross-sectional view of the packer gas tightness testing device according to an embodiment of the present invention after removing the infrared sensing module;

[0056] Figure 4 for Figure 3 A magnified view of a portion of point B in the middle;

[0057] Figure 5 This is a schematic diagram showing the connection of each component of the pipeline unit according to an embodiment of the present invention;

[0058] Figure 6 This is a cross-sectional view of the infrared sensing module described in an embodiment of the present invention;

[0059] Figure 7 This is a control principle diagram of the packer gas tightness performance testing device according to an embodiment of the present invention;

[0060] Figure 8 This is a flowchart of the method for testing the gas-tight performance of a packer according to an embodiment of the present invention;

[0061] Figure 9 This is a flowchart of the leakage measurement steps described in an embodiment of the present invention.

[0062] The components include: 100, packer gas tightness testing device; 110, piping unit; 111, gas path; 112, first control valve; 113, second control valve; 114, leakage gas pipe; 115, third control valve; 116, fourth control valve; 117, pressure relief pipe; 120, bubble measurement unit; 121, vision camera; 122, infrared sensor module; 1221, transmitting tube; 1222, receiving tube; 1223, microlens diffuser; 130, leakage measurement unit; 131, measuring cylinder; 132, macroscopic control component; 1321, mounting bracket; 1322, drive motor; 1323, lead screw; 1324, installation... Components: 1324A, Fine-tuning channel; 1325, Mounting plate; 1326, Spiral guide tube; 1327, Guide rod; 1328, First displacement sensor; 1329, Second displacement sensor; 133, Micro-control component; 1331, Micro-volume compensation module; 1332, Piston; 134, Temperature sensor; 140, Air pressure detection unit; 141, First air pressure sensor; 142, Second air pressure sensor; 150, Unit to be tested; 151, Upper pressure chamber; 152, Lower pressure chamber; 153, Central chamber; 160, Controller; 170, Housing; 171, Water collection space; A, Bubble detection area; 200, Component to be tested. Detailed Implementation

[0063] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Preferred embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of the invention.

[0064] It should be noted that when a component is said to be "fixed to" another component, it can be directly attached to the other component or there may be an intervening component. When a component is said to be "connected to" another component, it can be directly connected to the other component or there may be an intervening component. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0065] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0066] Please refer to Figures 1-7This invention provides a packer gas seal performance testing device 100, which includes a pipeline unit 110, a bubble measurement unit 120, a leakage measurement unit 130, a pressure detection unit 140, a test unit 150, and a controller 160. The bubble measurement unit 120 includes a visual camera 121 for acquiring visual data and an infrared sensor module 122 for acquiring infrared data. The leakage measurement unit 130 includes a measuring cylinder 131, a macro-control component 132, and a micro-control component 133. The macro-control component 132 is connected to the measuring cylinder 131, and the micro-control component 133 fine-tunes the volume of the measuring cylinder 131. The pressure detection unit 140 includes a first pressure sensor 141 for acquiring a first pressure value and a second pressure sensor 142 for acquiring a second pressure value. The test unit 150 is used to place the test piece 200. The test unit 150 is connected to the bubble measurement unit 120 and the leakage measurement unit 130 through the pipeline unit 110. The controller 160 is electrically connected to the vision camera 121, the infrared sensing module 122, the macro-control component 132, the micro-control component 133, the first pressure sensor 141, and the second pressure sensor 142. Exemplarily, the infrared sensing module 122 of this application uses an array composed of multiple sets of infrared emitting tubes 1221 and receiving tubes 1222 to form a blind-spot-free coverage in the detection area. Specifically, multiple sets of infrared sensors are arranged linearly along the horizontal and vertical directions. The emitting and receiving ends of each set of sensors are symmetrically distributed on both sides of the bubble detection area A, and the sensor spacing is ≤2mm, ensuring that the bubble can be captured by at least one set of sensors no matter where it appears in the area. Furthermore, a microlens diffuser 1223 is added to one end of the infrared emitting tube 1221 to ensure that the infrared light uniformly covers the entire detection area with a divergence angle of approximately 120°, avoiding local blind spots caused by concentrated light intensity. Each infrared sensor outputs an independent electrical signal, and the control module simultaneously acquires data from all channels via multiple ADCs. When infrared light passes through different media, its energy changes due to the absorption, reflection, and scattering of the medium. Bubbles and water have vastly different molecular structures and densities, resulting in drastically different effects on specific wavelengths of infrared light. This is the fundamental reason why infrared sensors can distinguish between bubbles and water. In bubble detection scenarios, infrared sensors typically select near-infrared light at 940nm. When no bubbles are generated, transmission is dominant. At this time, water molecules are dense and uniform, allowing infrared light to penetrate directly. Only a small amount of energy is absorbed by the water or reflected along its original direction, with no significant scattering. Therefore, the signal strength is stable and close to the initial emission intensity. When bubbles are generated, scattering is the main process. Due to the loose structure of gas molecules, random scattering occurs, and some light deviates from its original propagation direction and cannot be captured by the receiver. This results in a significant reduction in the infrared light energy obtained by the receiver, causing a sudden drop in signal strength or the appearance of pulse-like fluctuations.The leakage measurement unit 130 also includes a temperature sensor 134, which is installed inside the measuring cylinder 131 to acquire temperature data inside the measuring cylinder 131 in real time.

[0067] The controller 160 is configured to apply target pressure and target temperature to the test component 200 in the test unit 150, obtain bubble identification results by cross-validation of the acquired visual data and infrared data, and determine the test component 200 as V0 level if the bubble identification results meet the level determination conditions; otherwise, the leakage measurement step is executed.

[0068] The core innovations of this application are as follows: First, during bubble detection, the visual camera 121 and the infrared sensing module 122 work in coordination. The visual camera 121 acquires visual images of the bubbles, and near-infrared light is used to confirm the generation of the bubbles. This dual-signal cross-verification through visual morphology verification and infrared signal positioning improves the accuracy of identifying valid bubbles. Second, through the coordinated operation of the macro-control component 132 and the micro-control component 133, when calculating gas leakage, the macro-control component 132 is used to quickly and coarsely adjust the volume of the measuring cylinder 131, and then the micro-control component 133 is used to finely adjust the volume of the measuring cylinder 131, ensuring that the gas pressure inside the measuring cylinder 131 is equal to the gas pressure in the water collection space 171, thus improving the accuracy of calculating gas leakage. Third, the current leakage change trend can be obtained based on the current leakage change data, and then the future leakage can be predicted based on this trend. In other words, the packer detected by the detection device of this application is not only qualified at present, but also guaranteed to be qualified throughout its future service life.

[0069] The leakage measurement step includes: calculating the pressure difference using a first pressure value and a second pressure value; controlling the macro-control component 132 to adjust the position of the measuring cylinder 131 so that the pressure difference is within the first pressure difference range; controlling the micro-control component 133 to fine-tune the volume of the measuring cylinder 131 so that the pressure difference is within the second pressure difference range; calculating the gas leakage amount per unit time; if the gas leakage amount is less than the leakage threshold, the test item 200 is determined to be of level V1; otherwise, the test item 200 is determined to be unqualified. For example, the test item 200 is a packer. The first pressure difference range is set to less than 0.5 Pa, and the second pressure difference range is set to less than 0.1 Pa. In this embodiment, the unit time is set to 15 minutes. The unit time can be set according to specific requirements; for example, if the sealing performance of the packer is required to be high, the unit time can be set to 20 minutes or 30 minutes.

[0070] Please refer to Figure 1 , Figure 2 and Figure 3In one possible implementation, the packer gas tightness performance testing device 100 further includes a housing 170, which includes a water collection space 171. A measuring cylinder 131 is disposed in the water collection space 171. The macro-control component 132 includes a mounting frame 1321, a drive motor 1322, a lead screw 1323, a mounting block 1324, a mounting plate 1325, a spiral guide tube 1326, and a guide rod 1327. The mounting frame 1321 is fixedly mounted on the housing 170. The drive motor 1322 is fixedly mounted on the mounting frame 1321 and connected to the lead screw 1323. The lead screw 1323 is connected to the spiral guide tube 1326. The mounting block 1324 and the mounting plate 1325 are respectively connected to the two ends of the spiral guide tube 1326, and the mounting block 1324 is connected to the measuring cylinder 131. The two ends of the guide rod 1327 are respectively connected to the mounting block 1324 and the mounting plate 1325. For example, the core function of the macro-control component 132 is to maintain the pressure balance inside and outside the measuring cylinder 131, establishing a benchmark for leakage measurement. Before bubble detection, water needs to be added to the water collection space 171, with the water volume occupying approximately half of the space. It is understood that the housing 170, either entirely or partially in the bubble detection area A, is made of transparent material, allowing the vision camera 121 and infrared sensor module 122 to pass through the housing 170 to acquire bubble data. Of course, in specific applications, a transparent window can also be used. It should be noted that the measuring cylinder 131 has a hollow structure with no obstruction at the bottom. The bottom of the measuring cylinder 131 extends into the horizontal plane of the water collection space 171; that is, the volume of gas contained in the measuring cylinder 131 is determined by the space between the mounting block 1324 at the top of the measuring cylinder 131 and the horizontal plane at the bottom. The air pressure detection unit 140 collects the air pressure inside the measuring cylinder 131 and the atmospheric pressure inside the water collection space 171 through two air pressure sensors. When air pressure needs to be balanced, the controller 160 sends an adjustment command to the macro-control component 132. At this time, the drive motor 1322 drives the lead screw 1323 to rotate. The lead screw 1323 drives the mounting block 1324, which is fixed to the measuring cylinder 131, to move vertically up and down through the spiral guide tube 1326. If the air pressure inside the measuring cylinder 131 is higher than the atmospheric pressure, the drive motor 1322 rotates forward to drive the measuring cylinder 131 to rise, increasing the internal volume of the measuring cylinder 131 to reduce the air pressure. If the air pressure inside the measuring cylinder 131 is lower than the atmospheric pressure, the drive motor 1322 rotates in reverse to drive the measuring cylinder 131 to fall, decreasing the volume to increase the air pressure, until the difference between the two drops to within the first pressure difference range. This adjustment process ensures that the measuring cylinder 131 is always in a stable air pressure state, avoiding distortion of leakage calculation due to air pressure deviation, which is a prerequisite for accurate subsequent leakage measurement.The guide rod 1327 in the macro-control component 132 works in conjunction with the lead screw 1323 and the spiral guide tube 1326 to ensure the stable movement of the measuring cylinder 131. The guide rod 1327 is parallel to the axis of the measuring cylinder 131, which can limit the installation block 1324 to move only in the vertical direction, avoiding horizontal deviation when the measuring cylinder 131 is raised or lowered. If deviation occurs, it will cause the liquid level image recognition component to have a liquid level line recognition deviation, causing adjustment disorder. At the same time, the synergistic effect of the lead screw 1323 and the guide rod 1327 can make the raising and lowering process of the measuring cylinder 131 smooth without jamming or vibration, avoiding false pressure difference caused by liquid level fluctuation in the box 170 due to vibration, and further ensuring the accuracy of air pressure balance adjustment.

[0071] Please refer to Figure 3 and Figure 4 In one possible implementation, a fine-tuning channel 1324A for placing the micro-control component 133 is formed on the mounting block 1324. The fine-tuning channel 1324A communicates with the water collection space 171. The micro-control component 133 includes a micro-volume compensation module 1331 and a piston 1332. The micro-volume compensation module 1331 and the piston 1332 are connected, and the micro-volume compensation module 1331 is located on the side of the piston 1332 away from the water collection space 171. The fine-tuning channel 1324A is sealed by the piston 1332. The micro-volume compensation module 1331 drives the piston 1332 to move within the fine-tuning channel 1324A. It should be noted that the mounting block 1324 is partially embedded in the measuring cylinder 131. The mounting block 1324 is used to seal the upper end of the measuring cylinder 131. Therefore, the fine-tuning channel 1324A communicates with the measuring cylinder 131, that is, the fine-tuning channel 1324A is also part of the volume of the measuring cylinder 131. For example, the fine-tuning channel 1324A is cylindrical, and for ease of volume calculation, the axial diameter of the fine-tuning channel 1324A is a fixed straight hole. The micro-volume compensation module 1331 is a piezoelectric ceramic, which has nanometer-level displacement output capability and can drive the piston 1332 to achieve a micro-displacement of 0.001mm-0.01mm within the fine-tuning channel 1324A. The macro-control component 132 of this application performs large-scale volume adjustment, but cannot cover micro-displacements smaller than 0.01mm; the piezoelectric ceramic is responsible for micro-volume adjustment. One of the innovations of this application is that the macro-control component 132 and the micro-control component 133 can coordinate with each other. First, the pressure difference is adjusted to a range of less than 0.5Pa by the macro-control component 132, then the macro-control component 132 stops working, and then the pressure difference is adjusted to a range of less than 0.1Pa by the micro-control component 133. It can achieve both rapid volume adjustment and nanometer-level volume adjustment accuracy, meeting the needs of small pressure difference control.

[0072] The leakage amount in this application is indirectly calculated through the displacement of the measuring cylinder 131 and the piston 1332. Only when the gas pressure inside the measuring cylinder 131 is balanced with the atmospheric pressure can these two displacements be completely equivalent to the volume of the leaking gas. If the pressure difference is unbalanced, it will lead to errors in the calculated leakage amount. In addition, the packer testing in this application needs to be repeated in multiple batches. If the pressure difference benchmark for each batch of testing is inconsistent, the basic offset of the leakage amount calculation for each batch will be different. Even if the actual leakage amount is the same, the calculation results will differ due to the benchmark deviation, making it impossible to judge the batch quality stability of the packer through data comparison. However, by coordinating the macro-control component 132 and the micro-control component 133, the pressure difference is stabilized within the second pressure difference range of less than 0.1 Pa, ensuring that all batch testing is based on the same benchmark, which is beneficial to further improve the accuracy of the device testing.

[0073] Please refer to Figure 3 and Figure 4 In one possible implementation, the macro-control component 132 further includes a first displacement sensor 1328 for acquiring the displacement of the measuring cylinder 131, and the micro-control component 133 further includes a second displacement sensor 1329 for acquiring the displacement of the piston 1332.

[0074] Please refer to Figure 3 , Figure 4 and Figure 5 In one possible implementation, the pipeline unit 110 includes an air passage 111, a first control valve 112, and a second control valve 113. The first control valve 112 is used to control the connection and disconnection between the water collection space 171 and the unit under test 150, and the second control valve 113 is used to control the connection and disconnection between the unit under test 150 and the measuring cylinder 131. The unit under test 150 is externally connected to a pressurization system.

[0075] Please refer to Figure 3 , Figure 4 and Figure 5 ,like Figure 4 As shown, the first displacement sensor 1328, the first air pressure sensor 141, and the temperature sensor 134 are all mounted on the mounting block 1324, and the second displacement sensor 1329 is mounted on the piston 1332. Figure 5As shown, the measuring cylinder 131 is also connected to a pressure relief pipe 117 and a third control valve 115, which controls the opening and closing of the pressure relief pipe 117. After the leakage detection is completed, the third control valve 115 can be opened to release the pressure of the gas in the measuring cylinder 131. The piping unit 110 also includes a fourth control valve 116, which is located on the pipe connecting the pressurization system and the lower pressure chamber 152 and is used to control the opening and closing between the pressurization system and the lower pressure chamber 152. It can be understood that the first control valve 112, the second control valve 113, the third control valve 115, and the fourth control valve 116 are electrically connected to the controller 160.

[0076] Please refer to Figure 8 and Figure 9 A method for testing the gas-tight performance of a packer, applied to the aforementioned packer gas-tight performance testing device 100, the method comprising:

[0077] S1. Place the test piece 200 into the test unit 150 and seal the test unit 150; exemplary, the prepared test piece 200 is placed into the test unit 150 with the assistance of a loader. In this embodiment, the test unit 150 is a vessel body, and two test pieces 200 are placed into the vessel body, dividing the test unit 150 into an upper pressure chamber 151, a lower pressure chamber 152, and a central chamber 153.

[0078] S2. Apply the target pressure and target temperature to the test piece 200 inside the test unit 150, and perform a setting operation on the test piece 200. For example, heating and pressurizing are performed using an external heating device and a pressurizing system respectively. After reaching and stabilizing the target temperature and target pressure, a setting operation is performed. The setting operation can be mechanical setting or pressure setting. The gas output from the pressurizing system is nitrogen. On the one hand, nitrogen's chemical inertness is suitable for high-pressure testing environments, which helps eliminate safety risks. On the other hand, nitrogen has extremely low solubility in water. After leaked gas enters the water collection space 171 or the measuring cylinder 131, it will hardly dissolve in water, which helps avoid distortion in the leakage calculation and improves the accuracy of the detection.

[0079] S3. The bubble recognition result is obtained by cross-validation of the acquired visual data and infrared data.

[0080] S4. If the bubble identification result meets the level determination criteria, the test piece 200 is determined to be at level V0; if the bubble identification result does not meet the level determination criteria, the leakage measurement step is executed.

[0081] The leakage measurement steps include:

[0082] S41. Calculate the pressure difference using the first and second air pressure values, and control the macro-control component 132 to adjust the position of the measuring cylinder 131 so that the pressure difference is within the first pressure difference range;

[0083] S42, The micro-adjustment component 133 fine-tunes the volume of the measuring cylinder 131 so that the pressure difference value is within the second pressure difference range;

[0084] S43. Calculate the gas leakage amount per unit time. If the gas leakage amount is less than the leakage threshold, the test piece 200 is determined to be of level V1; otherwise, the test piece 200 is determined to be unqualified.

[0085] In one possible implementation, the bubble recognition result is obtained by cross-validation of the acquired visual data and infrared data, including:

[0086] The vision camera 121 acquires images of the bubble detection area A in real time. The images are binarized, and after extracting the bubble contours, feature matching is performed to obtain real-time visual judgment results. Feature matching includes the bubble's roundness, area, and contour regularity. For example, the real-time acquired RGB image is Gaussian filtered to eliminate high-frequency noise caused by small water particles. The RGB image is then converted to grayscale, and histogram equalization is used to enhance contrast. The ROI region is cropped, retaining only the bubble detection area A. The algorithm automatically calculates the grayscale histogram of the ROI region, finding a threshold T that maximizes the inter-class variance between bubbles and water. Pixels with grayscale values ​​less than T are identified as suspected bubble areas, while pixels with grayscale values ​​greater than or equal to T are identified as water. All edges of the ROI region are extracted using Canny edge detection, and only the outermost contour is extracted using an external contour retrieval mode. The minimum bounding rectangle area of ​​each contour is calculated, and contours with areas < 0.07 mm² are excluded, initially filtering out small impurities. Based on the three characteristics of bubble roundness, edge smoothness, and dynamic stability, non-bubble pseudo-contours are excluded. Contours that meet the above three criteria are marked as visually suspected bubbles.

[0087] The infrared sensing module 122 continuously emits near-infrared light into the bubble detection area A. The receiving end collects the real-time signal intensity. If the real-time signal intensity is less than the first signal threshold, it sends a suspected bubble infrared signal to the controller 160. For example, the first signal threshold is defined as the attenuation of the real-time signal collected by a group of infrared sensors of the infrared sensing module 122 exceeding 20%, that is, the real-time signal is lower than 80% of the initial reference signal.

[0088] The controller 160 retrieves the visual judgment result at the same timestamp. If the visual judgment result indicates that a bubble is suspected to exist, then the existence of a valid bubble is confirmed, and the timestamp of the valid bubble is recorded.

[0089] If the real-time signal strength acquired by the infrared sensing module 122 is less than the second signal threshold, and the attenuation duration of the real-time signal exceeds a preset threshold time, the controller 160 emits a low-intensity infrared suspected signal and activates the enhanced linkage mode; or, if the image analysis result of the vision camera 121 indicates the presence of a blurred outline, the controller 160 emits a visual suspected signal and activates the enhanced linkage mode; the enhanced linkage mode includes: acquiring the location coordinates of the low-intensity infrared suspected signal; performing at least one of the following operations on the vision camera 121: extending the exposure time, increasing the sampling density, enhancing noise reduction, polarization filtering, increasing the amount of light entering the location coordinates, and focusing on the location coordinates; and performing at least one of the following operations on the infrared sensing module 122: optimizing the signal trigger threshold, increasing the sampling frequency, and improving the spatial mapping accuracy.

[0090] If the real-time signal attenuation of one or more pairs of infrared sensors 122 is 15%-20%, which is lower than the normal trigger threshold of 20%, it is defined as a low-intensity signal. The controller 160 sends an enhancement command to the vision camera 121, optimizing parameters only for the suspected infrared area, avoiding global adjustments to prevent overexposure of the overall image. Alternatively, if the image analysis result of the vision camera 121 indicates the presence of blurred contours, the enhancement linkage mode will also be activated. Blurred contours are defined as bubble images with a roundness of 0.6-0.8 and an area of ​​0.03-0.07 mm². This area range corresponds to tiny bubbles or interference. At this scale, the contour edges of the vision camera 121 are easily distorted by water noise and light fluctuations, leading to parameter measurement deviations. In this case, the reliability of the visual signal is insufficient, therefore the enhancement linkage mode needs to be activated for further verification. Specific adjustments are as follows: Increase the amount of light entering the position coordinate area to make the grayscale difference of 0.1-0.3 mm tiny bubbles more obvious, increasing the bubble grayscale value by 15-25 units. Extending the exposure time improves the acquisition of light signals from the edges of tiny bubbles, preventing blurring caused by excessively fast shutter speeds. Increasing the sampling density captures the continuous motion trajectory of tiny bubbles, avoiding missed frames. Based on the spatial coordinates mapped from infrared signals, the focus is locked to this area, preventing localized defocusing caused by global focusing. Enhanced noise reduction uses a 7×7 bilateral filter and activates polarization filtering to offset high-frequency noise from exposure compensation, preserving the true edges of the bubbles. Standard noise reduction uses a 5×5 Gaussian filter without activating polarization filtering.

[0091] Optimizing the signal trigger threshold specifically includes: setting the trigger threshold to signal attenuation ≥20% in normal mode and adjusting it to ≥15% in enhanced mode to accommodate weak scattering signals caused by microbubbles. Adjusting sampling and detection parameters specifically includes: increasing the sampling frequency from 100Hz to 200Hz to capture signals momentarily blocked by microbubbles; extending the detection duration from 40ms single-frame verification to 250ms continuous 50-frame verification; and accumulating the signal attenuation trend. If 30 out of 50 frames meet the attenuation ≥15%, it is considered a continuous low-intensity suspected signal, avoiding false triggering due to instantaneous noise. Improving spatial mapping accuracy specifically includes: reducing the coordinate mapping error between the infrared channel and visual pixels from ±0.05mm to ±0.03mm, ensuring precise alignment between the position coordinate area and the visual ROI area, avoiding signal mismatch caused by spatial misalignment.

[0092] The timestamp synchronization accuracy has been improved from ±0.01s to ±0.005s, ensuring perfect time alignment between the visual frame and the infrared sampling point. The Euclidean distance d between the center of the infrared suspected region and the center of the visually blurred contour is ≤0.8mm, accommodating the positional deviation of microbubbles. For the blurred contour features accumulated over 3 consecutive frames at the visual end, if a contour with a roundness of 0.6-0.8 and an area of ​​0.03-0.07mm² exists in all 3 frames, and the center coordinate offset is ≤0.1mm / frame, conforming to the bubble's rising motion pattern, it is marked as a potential visual bubble. For the signal attenuation data accumulated over 30 consecutive frames at the infrared end, if the attenuation amplitude is stable at 15%-20% without abrupt changes, it is marked as a confirmed infrared suspected signal. If both a potential visual bubble and a confirmed infrared suspected signal are met simultaneously, it is determined to be a valid microbubble. If only a single condition is met, such as continuous low infrared intensity but no visual contour, it is determined to be an interference signal; the data is recorded but not included in the V0 level determination count.

[0093] The enhanced linkage mode is a temporary trigger state. Controller 160 automatically exits and restores normal detection parameters according to the following logic to ensure detection efficiency: The first exit is normal. When a valid microbubble is detected, controller 160 maintains the current parameters to complete one frame of data storage, and then restores the normal settings of the camera and infrared module within 0.1 seconds, continuing to perform routine dual-signal cross-verification. The duration of the enhanced linkage mode is set to 3 seconds. If the combined conditions of visual potential bubbles and infrared confirmation of suspected signals are not met within 3 seconds, normal parameters are automatically restored. After exiting, if the enhanced conditions are triggered again within 10 seconds, it is only allowed to start once to avoid parameter fluctuations caused by frequent switching.

[0094] Another innovative aspect of this application's technical solution lies in addressing the problem of identifying microbubbles. On one hand, it overcomes the limitations of single-signal recognition through dual-signal collaborative verification. The infrared sensing module 122 forms a blind-spot-free coverage using multiple pairs of diode arrays, utilizing the scattering characteristics of near-infrared light by microbubbles to capture weak signals that are difficult to identify with traditional single-array infrared sensors. The vision camera 121 distinguishes microbubbles from static impurities through morphological and dynamic multi-feature matching. When the two work together, infrared provides suspected area localization, and vision provides morphological verification. In principle, this avoids the problems of single infrared sensors missing weak signals and single vision sensors misjudging blurred contours, ensuring that microbubbles are neither missed nor misjudged. On the other hand, by optimizing visual parameters to suit the morphological characteristics of microbubbles, the visual processing breaks through the limitations of traditional fixed thresholds, addressing the unclear outlines and irregular edges of microbubbles. It dynamically adapts to changes in light through an adaptive segmentation algorithm, avoiding outline loss due to light fluctuations; it relaxes the morphological judgment threshold to accommodate non-standard microbubble shapes; and in enhanced linkage mode, it adjusts exposure, focus, and filtering parameters for suspected infrared areas, fundamentally improving the grayscale difference between bubbles and water and eliminating reflective interference, allowing microbubble outlines to be clearly separated from the background, solving the problem of traditional vision failing to identify due to morphological blur. Thirdly, based on the principle of signal correlation, it precisely synchronizes the timestamps of visual and infrared signals, ensuring both respond to the same microbubble and avoiding missed detections due to spatiotemporal misalignment; through precise spatial coordinate mapping, it aligns the suspected infrared area with the visual detection area, avoiding signal mismatch caused by regional deviations; and it uses multi-frame signal accumulation for verification, fundamentally eliminating accidental interference such as reflections and noise, ensuring that the recognition result is not an interfering signal but a real microbubble, significantly improving recognition reliability.

[0095] In one possible implementation, if the bubble identification result meets the level determination criteria, the test item 200 is determined to be at level V0; if the bubble identification result does not meet the level determination criteria, the leakage measurement step is performed, including:

[0096] If no valid bubbles appear within the first preset time after the start of the test, the test item 200 is determined to be of level V0; for example, in this embodiment, the first preset time is 15 minutes.

[0097] If a valid bubble appears within the first preset time after the start of the test, the test time is automatically extended, starting from the time the first valid bubble appears, and waiting for the second bubble. If the interval between the second and first valid bubbles is greater than the second preset time, the test item 200 is determined to be of level V0. If the interval between the second and first valid bubbles is less than or equal to the second preset time, the leakage measurement step is executed. For example, in this embodiment, the second preset time is 15 minutes.

[0098] The formula for calculating gas leakage is:

[0099]

[0100] In the formula:

[0101] This indicates the cross-sectional area of ​​the inner cavity of the measuring cylinder 131;

[0102] This indicates the displacement of the measuring cylinder 131 from the start to the end of the leakage detection;

[0103] This represents the cross-sectional area of ​​the fine-tuning channel 1324A;

[0104] This indicates the displacement of piston 1332 from the start to the end of the leakage detection.

[0105] In one possible implementation, the method further includes: calculating the continuous leakage amount according to the gas leakage amount calculation formula, storing historical data of the continuous leakage amount, extracting the leakage amount change slope, temperature sensitivity coefficient and pressure sensitivity coefficient features, predicting the future leakage amount change trend of the packer based on time series algorithm and operating condition correlation model, and outputting the prediction and judgment results of the packer's gas sealing performance.

[0106] The following is the calculation process for the future leakage trend:

[0107] The formula for calculating instantaneous leakage is as follows:

[0108]

[0109] In the formula, This represents the instantaneous leakage rate within a certain data collection period. This indicates the initial volume of the measuring cylinder 131. This indicates the change in internal pressure of the measuring cylinder 131 during the acquisition period, which is collected by the first pressure sensor 141. ; This indicates a standard absolute temperature of 298.15 K; This indicates that the standard atmospheric pressure is 101.325 kPa. The absolute temperature inside the measuring cylinder 131 is represented by the temperature sensor 134 inside the measuring cylinder 131. The volume of the measuring cylinder 131 is fixed. When leaked gas enters, it only causes an increase in the pressure inside the cylinder. The pressure change is converted into the volume of leaked gas using the ideal gas law, thus eliminating the influence of the constant volume.

[0110] The formula for calculating the slope of pressure change is as follows:

[0111]

[0112] In the formula, It represents the average slope of the pressure change inside measuring cylinder 131 over 24 hours, which can reflect the rate of pressure increase caused by leakage; This indicates the total change in internal pressure of measuring cylinder 131 over 24 hours, which is continuously collected by the first air pressure sensor 141. Indicates a time period.

[0113] The formula for calculating the temperature sensitivity coefficient is as follows:

[0114]

[0115] The change in pressure inside the measuring cylinder 131 when the temperature changes by 1°C is used to correct for spurious pressure changes caused by temperature. This indicates the change in internal pressure when only the temperature changes; The temperature change of the measuring cylinder 131 is represented by the temperature sensor 134 inside the measuring cylinder 131.

[0116] The formula for predicting the internal pressure of the measuring cylinder 131 in the future is as follows:

[0117]

[0118] In the formula, Indicates the future The pressure inside the measuring cylinder 131 at any given time; The pressure value inside the measuring cylinder 131 at the start of the prediction is indicated, which is the real-time value of the first air pressure sensor 141. Indicates the future forecast period; This indicates the amount of temperature change in the cylinder during the future forecast period.

[0119] The formula for calculating future leakage is as follows:

[0120]

[0121] In the formula, This represents the leakage amount over a 15-minute period of the future forecast cycle, used for V1 level determination at a future time; 15 / 60 represents the time conversion factor. This indicates the temperature of the measuring cylinder 131 within the future prediction period.

[0122] First, predict the pressure inside the measuring cylinder 131 in the future, convert the predicted pressure difference value into the leakage amount over 15 minutes, and compare it with the threshold of document V1 level to determine whether it is qualified.

[0123] Working process of packer gas tightness testing device 100:

[0124] With the assistance of a loader, the test piece 200 is placed into the test unit 150, and a test casing is lowered into the test unit 150. If it is necessary to simulate a downhole multi-storage isolation scenario, two test pieces 200 can be placed, so that the test unit 150 is divided into an independent upper pressure chamber 151, a lower pressure chamber 152, and a central chamber 153. The hatch of the test unit 150 is closed and sealed, and the first control valve 112 and the second control valve 113 are closed to ensure that the test unit 150 is temporarily not connected to other components to avoid initial gas leakage interference. The controller 160 sends a command to the pressurization system connected to the unit under test 150. The heating device raises the temperature inside the unit under test 150 to the target test temperature. The pressurization system pressurizes either the upper pressure chamber 151 or the lower pressure chamber 152 inside the unit under test 150 to the target pressure. If the pressurization system is connected to the lower pressure chamber 152, the water collection space 171 and the measuring cylinder 131 are connected to the upper pressure chamber 151. If the pressurization system is connected to the upper pressure chamber 151, the water collection space 171 and the measuring cylinder 131 are connected to the lower pressure chamber 152. The target temperature and target pressure are set according to actual needs, with the aim of simulating the downhole working environment of the packer. The controller 160 receives temperature and pressure data from the pressurization system in real time. If the fluctuation is ≤±0.5℃ within 30 minutes, the temperature is stable; if the fluctuation is ≤±0.1MPa within 30 minutes, the pressure is stable. Once the temperature and pressure are stable, temperature and pressure control is stopped, completing the downhole working condition simulation. The controller 160 controls the pressurization system to perform the setting operation: if it is a mechanical setting, it outputs a command to the force loading device to apply a setting force; if it is a pressure setting, it pressurizes the setting chamber of the test piece 200. After setting, the upper pressure chamber 151, lower pressure chamber 152, and central chamber 153 are not connected to each other. The piping unit 110 also includes a leakage gas pipe 114, which is inserted into the water to a depth of about 5 mm. The leakage gas pipe 114 is connected to the gas passage 111. When there is leaking gas in the upper pressure chamber 151, the leaking gas enters the water in the water collection space 171 through the gas passage 111 and the leakage gas pipe 114, thereby generating bubbles. The controller 160 controls the first control valve 112 of the pipeline unit 110 to open and the second control valve 113 to remain closed, so that the upper pressure chamber 151 of the unit under test 150 (taking the pressurization system and the lower pressure chamber 152 as an example) is connected to the water collection space 171; if there is leaking gas in the upper pressure chamber 151, it can enter the bubble detection area A of the water collection space 171 through the pipeline unit 110.

[0125] During the bubble detection phase, the vision camera 121 acquires images of the bubble detection area A in real time. The controller 160 binarizes the images, extracts contour features, and matches them with a bubble template to generate a real-time visual judgment result. This result includes two categories: suspected bubble and no bubble. The infrared sensor module 122 continuously emits 940nm near-infrared light into the bubble detection area A, and the receiver collects the signal intensity in real time. If a bubble is present, it will scatter near-infrared light, causing the signal intensity to fall below a first signal threshold (e.g., 80% of the initial reference signal). The infrared sensor module 122 immediately sends a suspected bubble infrared signal to the controller 160. Understandably, before bubble detection, an initial reference signal for near-infrared light in the bubble detection area A (where no bubbles have formed) needs to be determined. The visual judgment result and the infrared signal at the same timestamp are retrieved. If both are suspected bubbles, a valid bubble is confirmed, and its timestamp is recorded. If only one signal is a suspected bubble, it is considered interference, such as water impurities or light reflection, and is not recorded as a valid bubble. If no valid bubble appears within 15 minutes, the controller 160 directly determines the test unit 200 to be at level V0, closes the first control valve 112, opens the pressure relief valve of the test unit 150, and completes the test. If one valid bubble appears within 15 minutes, the controller 160 automatically extends the test time, starting from the time the first valid bubble is generated. If the interval between the second valid bubble and the first bubble exceeds 15 minutes, it is still determined to be at level V0; if the interval does not exceed 15 minutes, it is determined that level V0 is not met, and the test enters the level V1 leakage detection stage.

[0126] During the leakage detection phase, controller 160 closes the first control valve 112 of pipeline unit 110 and opens the second control valve 113, connecting the upper pressure chamber 151 to the measuring cylinder 131; simultaneously, it closes other passages in the water collection space 171 to ensure that leaked gas only enters the measuring cylinder 131. The first pressure sensor 141 collects the first pressure value inside the measuring cylinder 131 in real time, and the second pressure sensor 142 collects the second atmospheric pressure value. Controller 160 calculates the pressure difference ΔP = |first pressure value - second pressure value| every 0.1 seconds. During leakage detection, if there is leaked gas in the upper pressure chamber 151, the leaked gas will enter the measuring cylinder 131, causing the pressure inside the measuring cylinder 131 to rise and the water level inside the measuring cylinder 131 to drop. The amount of gas leakage is collected per unit time (15 minutes in this embodiment). Timing begins when the leakage gas collection starts, and after 15 minutes, the second control valve 113 is closed, and the gas leakage calculation begins. First, the initial position L0 of the measuring cylinder 131 and the initial position D0 of the piston 1332 are acquired by the first displacement sensor 1328 and the second displacement sensor 1329. The controller 160 sends a command to the drive motor 1322 of the macro-control component 132, which drives the lead screw 1323 to rotate. The lead screw 1323 drives the measuring cylinder 131 to rise vertically along the guide rod 1327 via the spiral guide tube 1326. During the ascent of the measuring cylinder 131, the distance between the top of the measuring cylinder 131 and the horizontal plane increases, resulting in an increase in the volume of the measuring cylinder 131 and a gradual decrease in the air pressure inside the measuring cylinder 131. The first displacement sensor 1328 acquires the initial and real-time positions of the measuring cylinder 131 in real time and feeds them back to the controller 160. When the controller 160 detects ΔP < 0.5 Pa, it controls the drive motor 1322 to stop rotating, the coarse adjustment of the macro-control component 132 ends, and the air pressure inside the measuring cylinder 131 is initially close to atmospheric pressure. The controller 160 sends a command to the micro-volume compensation module 1331 of the micro-control component 133, causing the piezoelectric ceramic to drive the piston 1332 to make a small movement within the fine-tuning channel 1324A of the mounting block 1324. For example, if ΔP = 0.3 Pa, which is still higher than the upper limit of the second differential pressure range, the piezoelectric ceramic pushes the piston 1332 to move away from the water collection space 171, increasing the total volume of the fine-tuning channel 1324A and the measuring cylinder 131, further reducing the air pressure inside the measuring cylinder 131. The second displacement sensor 1329 collects the initial and real-time positions of the piston 1332 in real time and feeds them back to the controller 160. When the controller 160 detects that ΔP < 0.1 Pa, it controls the piezoelectric ceramic to stop moving, ensuring that the air pressure inside the measuring cylinder 131 is completely balanced with the atmospheric pressure, providing a unified benchmark for leakage calculation. At this time, the final position L1 of the measuring cylinder 131 and the final position D1 of the piston 1332 are collected by the first displacement sensor 1328 and the second displacement sensor 1329.The controller 160 calculates the leakage amount according to the above formula. First, it obtains the cross-sectional area S1 of the inner cavity of the measuring cylinder 131 and the cross-sectional area S2 of the fine-tuning channel 1324A. The displacement of the measuring cylinder 131 is L = L1 - L0, and the displacement of the piston 1332 is D = D1 - D0. Finally, the leakage amount is obtained as S1 × L + S2 × D. If the calculated leakage amount in 15 minutes is < 20 cm³, the controller 160 determines that the test piece 200 is of level V1; if it is ≥ 20 cm³, the test piece 200 is determined to be unqualified.

[0127] During the continuous measurement and trend prediction phase, the controller 160 sets a continuous acquisition cycle (e.g., once every hour), repeating the macroscopic coarse adjustment, microscopic fine adjustment, and displacement acquisition process. It calculates the instantaneous leakage within each acquisition cycle and converts the data to volume under standard conditions (25℃, 101.325 kPa) to avoid data distortion caused by temperature and pressure fluctuations. The data storage module is electrically connected to the controller 160 and stores historical data from the continuous measurement, including timestamps, instantaneous leakage under standard conditions, L, D, first pressure value, second pressure value, and the temperature and pressure of the measured unit 150. The controller 160 extracts characteristic parameters from the historical data, including the leakage rate change slope, temperature sensitivity coefficient, and pressure sensitivity coefficient. The leakage rate change slope is defined as the slope obtained by fitting a trend line of the average leakage over 24 hours using linear regression. The temperature sensitivity coefficient is defined as the leakage rate change when the temperature of the measured unit 150 changes by 1℃. The pressure sensitivity coefficient is defined as the leakage rate change when the pressure of the measured unit 150 changes by 1 MPa. The controller 160 calls the time-series algorithm module built into the data storage module to predict the baseline values ​​of leakage for the next 24, 48, and 72 hours. It then calls the operating condition correlation model module to calculate the operating condition correction based on the target temperature and pressure changes within the prediction period. The correction is calculated as: Correction = Temperature Sensitivity Coefficient × Temperature Change + Pressure Sensitivity Coefficient × Pressure Change. The controller 160 uses the baseline values ​​and corrections as the predicted future leakage. For example, if a component 200 to be tested needs to operate continuously underground for 72 hours and is required to reach Level V1, then the leakage after 72 hours can be predicted by observing the leakage trend. If the predicted result still meets the Level V1 requirement, then the component 200 cannot complete this task.

[0128] After the test is completed, the pressure of the test unit 150 and the measuring cylinder 131 is released, the drive motor 1322 of the macro control component 132 reverses, and drives the measuring cylinder 131 to descend to the initial position; the piezoelectric ceramic drive piston 1332 of the micro control component 133 resets, so that the volume of the fine adjustment channel 1324A returns to the initial value.

[0129] The above embodiments merely illustrate several implementation methods of the present invention, and their descriptions are relatively specific and detailed, but they should not be construed as limiting the scope of the patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this patent should be determined by the appended claims.

Claims

1. A packer gas-tightness testing device, characterized in that, include: Piping unit; The bubble measurement unit includes a visual camera for acquiring visual data and an infrared sensing module for acquiring infrared data. The leakage measurement unit includes a measuring cylinder, a macro-control component, and a micro-control component. The macro-control component is connected to the measuring cylinder, and the micro-control component finely adjusts the volume of the measuring cylinder. The air pressure detection unit includes a first air pressure sensor and a second air pressure sensor. The first air pressure sensor collects the first air pressure value inside the measuring cylinder in real time, and the second air pressure sensor collects the second air pressure value of the atmospheric environment. The test unit is used to place the test item, and the test unit is connected to the bubble measuring unit and the leakage measuring unit respectively through the pipeline unit; The controller is electrically connected to the vision camera, the infrared sensing module, the macro-control component, the micro-control component, the first air pressure sensor, and the second air pressure sensor, respectively. The controller is configured to apply target pressure and target temperature to the test piece in the test unit, obtain bubble recognition results by cross-validation of the acquired visual data and infrared data, and determine the test piece as V0 level if the bubble recognition results meet the level determination conditions. If the bubble identification result does not meet the level determination criteria, then the leakage measurement step is executed; The leakage measurement step includes: The pressure difference is calculated using the first and second air pressure values, and the macro-control component is used to adjust the position of the measuring cylinder so that the pressure difference is within the first pressure difference range. The micro-adjustment component is controlled to fine-tune the volume of the measuring cylinder so that the pressure difference value is within the second pressure difference range; Calculate the amount of gas leakage per unit time. If the amount of gas leakage is less than the leakage threshold, the test item is determined to be of level V1; otherwise, the test item is determined to be unqualified. The packer airtightness testing device also includes a housing, which includes a water collection space. The measuring cylinder is disposed in the water collection space. The macro-control component includes a mounting frame, a drive motor, a lead screw, a mounting block, a mounting plate, a spiral guide tube, and a guide rod. The mounting frame is fixedly installed in the housing. The drive motor is fixedly installed in the mounting frame and connected to the lead screw. The lead screw is connected to the spiral guide tube. The mounting block and the mounting plate are respectively connected to the two ends of the spiral guide tube, and the mounting block is connected to the measuring cylinder. The two ends of the guide rod are respectively connected to the mounting block and the mounting plate. The mounting block has a fine-tuning channel for placing the micro-control component. The fine-tuning channel is connected to the water collection space. The micro-control component includes a micro-volume compensation module and a piston. The micro-volume compensation module is connected to the piston, and the micro-volume compensation module is located on the side of the piston away from the water collection space. The fine-tuning channel is sealed by the piston. The micro-volume compensation module drives the piston to move within the fine-tuning channel. The macro-control component further includes a first displacement sensor for acquiring the displacement of the measuring cylinder, and the micro-control component further includes a second displacement sensor for acquiring the displacement of the piston. The pipeline unit includes an air path, a first control valve, and a second control valve. The first control valve is used to control the connection between the water collection space and the unit under test, and the second control valve is used to control the connection between the unit under test and the measuring cylinder. The unit under test is externally connected to a pressurization system.

2. A method for testing the gas-tight performance of a packer, applied to the packer gas-tight performance testing device as described in claim 1, characterized in that, The method includes: S1. Place the component to be tested into the test unit and seal the test unit; S2. Apply target pressure and target temperature to the test piece in the test unit and perform a setting and sealing operation on the test piece; S3. The bubble recognition result is obtained by cross-validating the acquired visual data and infrared data. S4. If the bubble identification result meets the level determination criteria, the test item is determined to be of level V0; if the bubble identification result does not meet the level determination criteria, the leakage measurement step is executed. The leakage measurement step includes: S41. Calculate the pressure difference value using the first air pressure value and the second air pressure value, and control the macro-control component to adjust the position of the measuring cylinder so that the pressure difference value is within the first pressure difference range; S42. Control the micro-adjustment component to fine-tune the volume of the measuring cylinder so that the pressure difference value is within the second pressure difference range; S43. Calculate the gas leakage amount per unit time. If the gas leakage amount is less than the leakage threshold, the test piece is determined to be of level V1; otherwise, the test piece is determined to be unqualified.

3. The method for testing the gas-tight performance of a packer according to claim 2, characterized in that, The bubble recognition result obtained by cross-validating the acquired visual and infrared data includes: The visual camera acquires images of the bubble detection area in real time, performs binarization on the images, extracts the bubble contours, and performs feature matching to obtain real-time visual judgment results. The infrared sensing module continuously emits near-infrared light into the bubble detection area, and the receiving end collects the real-time signal strength. If the real-time signal strength is less than the first signal threshold, it sends a suspected bubble infrared signal to the controller. The controller retrieves the visual judgment results at the same timestamp. If the visual judgment result indicates that a bubble is suspected to exist, then the existence of a valid bubble is confirmed, and the timestamp of the valid bubble is recorded.

4. The method for testing the gas-tight performance of a packer according to claim 3, characterized in that, If the real-time signal strength collected by the infrared sensing module is less than the second signal threshold, and the attenuation duration of the real-time signal exceeds a preset threshold time, the controller sends out a low-intensity infrared suspected signal and activates the enhanced linkage mode; or, if the image analysis result of the vision camera shows that there is a blurred outline, the controller sends out a visual suspected signal and activates the enhanced linkage mode. The enhanced linkage mode includes: Obtain the location coordinates of the suspected low-intensity infrared signal. The visual camera is subjected to at least one of the following operations: extending the exposure time, increasing the sampling density, enhancing noise reduction, applying polarization filtering, increasing the amount of light entering the position coordinate region, and focusing on the position coordinate region. The infrared sensing module shall be subjected to at least one of the following operations: optimizing the signal trigger threshold, increasing the sampling frequency, and improving the spatial mapping accuracy.

5. The method for testing the gas-tight performance of a packer according to claim 2, characterized in that, If the bubble recognition result meets the level determination criteria, then the item to be inspected is determined to be at level V0. If the bubble identification result does not meet the level determination criteria, the leakage measurement steps include: If no valid bubbles appear within the first preset time after the start of the test, the test piece is determined to be of grade V0. If a valid bubble appears within the first preset time after the start of the test, the test time is automatically extended. The timer starts from the time when the first valid bubble appears and waits for the second bubble. If the interval between the second valid bubble and the first valid bubble is greater than the second preset time, the test item is determined to be of level V0. If the interval between the second valid bubble and the first valid bubble is less than the second preset time, the leakage measurement step is executed.

6. The method for testing the gas-tight performance of a packer according to claim 2, characterized in that, The formula for calculating the gas leakage amount is: ； In the formula: This indicates the cross-sectional area of ​​the inner cavity of the measuring cylinder; This indicates the displacement of the measuring cylinder from the start to the end of the leakage detection process; This represents the cross-sectional area of ​​the fine-tuning channel; This indicates the piston displacement from the start to the end of the leak detection.

Images