Device and method for detecting air-tight sealing performance of packer

Abstract

The invention belongs to the technical field of packer detection, and relates to a method for detecting the airtight sealing performance of a packer, and a device for detecting the airtight sealing performance of the packer comprises a pipeline unit, a bubble measuring unit, a leakage rate measuring unit, an air pressure detecting unit, a to-be-detected unit and a controller. Performing double-signal cross validation according to the obtained visual data and infrared data to obtain a bubble recognition result, and if the bubble recognition result meets a grade judgment condition, judging that the to-be-detected piece is at a V0 grade; and if the bubble identification result does not meet the grade judgment condition, executing a leakage rate measurement step. In the first aspect, during bubble detection, through double-signal cooperative cross validation of visual form verification and infrared signal positioning and targeted recognition of tiny bubbles through an enhanced linkage mode, the accuracy of effective bubble recognition is improved. On the second aspect, the volume of the measuring cylinder is coarsely adjusted and finely adjusted through cooperation of the macroscopic adjusting and controlling assembly and the microcosmic adjusting and controlling assembly, and the accuracy of calculating the gas leakage rate is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of packer detection, and in particular to a packer air tightness performance detection device and a detection method thereof. BACKGROUND

[0002] In the field of oil and gas field development, as the core sealing component of downhole separate layer exploitation, water injection and fracturing operation, the air tightness performance of the packer directly determines the safety production efficiency and wellbore integrity of the oil and gas well. If the packer has sealing failure, it is easy to cause interlayer channeling, abnormal wellhead pressure, natural gas leakage and even blowout accidents. Therefore, before the packer is put into the well, the ground detection device needs to simulate the downhole high pressure and high temperature working condition to strictly verify the air tightness performance, so as to ensure that it meets the industry V0, V1 level standards.

[0003] However, the current air tightness performance detection method has significant deficiencies in actual application. Many traditional methods are often limited to surface observation of leakage phenomena, lacking in-depth capture of dynamic changes in the leakage process, especially subtle leakage in complex environments is difficult to accurately identify. This limitation often makes the detection results not comprehensive enough, easily ignoring potential risks, and thus affecting the stability of equipment operation.

[0004] The deeper technical difficulty lies in how to accurately quantify the leakage volume and identify the micro-bubbles. First, the measurement of the leakage volume requires very high precision, because even a small volume change may reflect a major problem with the sealing performance of the equipment, but existing technologies often have difficulty in balancing large-scale adjustment and fine adjustment in volume control. Second, the identification of micro-bubbles is difficult to cover comprehensively by relying solely on a single perspective, for example, in the identification of micro-bubbles using a single visual camera, the micro-bubbles cannot be identified due to blurred shape, and in the use of a single infrared sensor, it is difficult to identify weak signals. These factors will lead to inaccurate detection results. SUMMARY

[0005] The purpose of the present application is to provide a packer air tightness performance detection device, which aims to solve the technical problems of low accuracy and difficulty in detecting micro-bubbles of existing detection devices.

[0006] To solve the above technical problems, a packer air tightness performance detection device is provided, comprising: a pipeline unit; a bubble measurement unit, comprising a visual camera for acquiring visual data and an infrared sensor module for acquiring infrared data; a leakage volume measurement unit, comprising a measuring cylinder, a macroscopic control component and a microscopic control component, the macroscopic control component is connected with the measuring cylinder, and the microscopic control component fine tunes the volume of the measuring cylinder; The air pressure detection unit comprises a first air pressure sensor for obtaining a first air pressure value and a second air pressure sensor for obtaining a second air pressure value. The to-be-tested unit is used for placing a to-be-tested piece, and is in communication with the bubble measurement unit and the leakage amount measurement unit through the pipeline unit respectively. The controller is electrically connected with the visual camera, the infrared sensing module, the macroscopic regulation and control assembly, the microscopic regulation and control assembly, the first air pressure sensor and the second air pressure sensor respectively. The controller is configured to apply a target pressure and a target temperature to the to-be-tested piece in the to-be-tested unit, cross-verify the obtained visual data and infrared data double signals to obtain a bubble recognition result, and if the bubble recognition result meets a grade determination condition, determine that the to-be-tested piece is of V0 grade; if the bubble recognition result does not meet the grade determination condition, execute a leakage amount measurement step. The leakage amount measurement step comprises: A first air pressure value and a second air pressure value are calculated to obtain an air pressure difference value, and the macroscopic regulation and control assembly is controlled to adjust the position of the measuring cylinder so that the air pressure difference value is within a first pressure difference range. The microscopic regulation and control assembly is controlled to finely adjust the volume of the measuring cylinder so that the air pressure difference value is within a second pressure difference range. The gas leakage amount per unit time is calculated, and if the gas leakage amount is less than a leakage amount threshold value, the to-be-tested piece is determined to be of V1 grade, otherwise the to-be-tested piece is determined to be unqualified.

[0007] Further, the packer air tightness detection device further comprises a box body, the box body comprises a water collecting space, the measuring cylinder is arranged in the water collecting space, the macroscopic regulation and control assembly comprises a mounting frame, a driving motor, a screw rod, a mounting block, a mounting plate, a spiral conduit and a guide rod, the mounting frame is fixedly installed on the box body, the driving motor is fixedly installed on the mounting frame and connected with the screw rod, the screw rod is connected with the spiral conduit, the mounting block and the mounting plate are respectively connected to two ends of the spiral conduit, and the mounting block is connected with the measuring cylinder, and the guide rod is connected with the mounting block and the mounting plate at two ends.

[0008] Further, a fine adjustment channel for placing the microscopic regulation and control assembly is formed on the mounting block, the fine adjustment channel is in communication with the water collecting space, the microscopic regulation and control assembly comprises a micro-volume compensation module and a piston, the micro-volume compensation module is connected with the piston, and the micro-volume compensation module is arranged on a side of the piston away from the water collecting space, the fine adjustment channel is sealed by the piston, and the micro-volume compensation module drives the piston to move in the fine adjustment channel.

[0009] Further, the macroscopic regulation component further comprises a first displacement sensor for acquiring the displacement amount of the measuring cylinder, and the microscopic regulation component further comprises a second displacement sensor for acquiring the displacement amount of the piston.

[0010] Further, the pipeline unit comprises an air path, a first control valve and a second control valve, the first control valve is used to control the on-off between the water collection space and the unit to be measured, and the second control valve is used to control the on-off between the water collection space and the measuring cylinder, and the unit to be measured is connected with a pressurizing system.

[0011] A detection method for the air tightness of a packer, applied to the packer air tightness detection device, the method comprises: S1, placing the detection piece into the unit to be measured, and sealing the unit to be measured; S2, applying a target pressure and a target temperature to the detection piece in the unit to be measured, and performing a setting operation on the detection piece; S3, obtaining a bubble recognition result according to the cross verification of the visual data and the infrared data double signals; S4, if the bubble recognition result meets the grade determination condition, it is determined that the detection piece is of V0 grade; if the bubble recognition result does not meet the grade determination condition, a leakage amount measurement step is performed; The leakage amount measurement step comprises: S41, calculating a gas pressure difference value through the first gas pressure value and the second gas pressure value, and controlling the macroscopic regulation component to adjust the position of the measuring cylinder so that the gas pressure difference value is within a first pressure difference range; S42, controlling the microscopic regulation component to finely adjust the volume of the measuring cylinder so that the gas pressure difference value is within a second pressure difference range; S43, calculating the gas leakage amount per unit time, if the gas leakage amount is less than a leakage amount threshold, it is determined that the detection piece is of V1 grade, otherwise it is determined that the detection piece is unqualified.

[0012] Further, the bubble recognition result obtained according to the cross verification of the visual data and the infrared data double signals comprises: The visual camera acquires images of the bubble detection area in real time, performs binaryzation processing on the images, extracts bubble contours, and then performs feature matching to obtain real-time visual judgment results; The infrared sensing module continuously emits near-infrared light to the bubble detection area, and the receiving end collects real-time signal intensity, if the real-time signal intensity is less than a first signal threshold, a suspected bubble infrared signal is sent to the controller; The controller calls the visual judgment result of the same timestamp, if the visual judgment result is suspected to have a bubble, it is confirmed that there is an effective bubble, and the timestamp of the effective bubble is recorded.

[0013] Further, if the real-time signal intensity collected by the infrared sensing module is less than a second signal threshold value, and the duration of the attenuation of the real-time signal exceeds a preset threshold time, the controller sends an infrared low-intensity suspected signal and starts a strengthened linkage mode; or, if the image analysis result of the visual camera is that there is a blurred outline, the controller sends a visual suspected signal and starts the strengthened linkage mode. The strengthened linkage mode comprises: acquiring a position coordinate area where the infrared low-intensity suspected signal appears; performing at least one of the following operations on the visual camera: prolonging an exposure time, increasing a sampling density, enhancing noise reduction, enhancing a polarization filtering function, increasing an amount of light entering the position coordinate area, and performing a spot focusing on the position coordinate area; performing at least one of the following operations on the infrared sensing module: optimizing a signal triggering threshold value, increasing a sampling frequency, and improving spatial mapping accuracy.

[0014] Further, if the bubble recognition result meets the grade determination condition, it is determined that the to-be-detected piece is of V0 grade; if the bubble recognition result does not meet the grade determination condition, a leakage measurement step is performed, which comprises: if no effective bubble appears within a first preset time after detection starts, it is determined that the to-be-detected piece is of V0 grade; if one effective bubble appears within the first preset time after detection starts, the detection time is automatically prolonged, the time is counted from the time when the first effective bubble appears, and the second bubble is waited for; if the interval time between the second effective bubble and the first effective bubble is greater than a second preset time, it is determined that the to-be-detected piece is of V0 grade; if the interval time between the second effective bubble and the first effective bubble does not exceed the second preset time, the leakage measurement step is performed.

[0015] Further, the calculation formula of the gas leakage amount is: In the formula, A represents the cross-sectional area of the inner cavity of the measuring cylinder; A represents the cross-sectional area of the inner cavity of the measuring cylinder; S represents the displacement amount of the measuring cylinder from the start to the end of the leakage amount detection; A represents the cross-sectional area of the inner cavity of the measuring cylinder; S represents the displacement amount of the piston from the start to the end of the leakage amount detection.

[0016] Implementing the embodiments of the present application will have the following beneficial effects: The packer gas sealing performance detection device and the detection method thereof provided by the embodiment have the following advantages: in the first aspect, when detecting bubbles, the visual camera and the infrared sensing module are coordinated and matched, the visual camera is used to collect a visual image of the bubbles, near-infrared light is used to confirm the generation of the bubbles, the bubbles are identified through the cross verification of the visual form verification and the infrared signal positioning, and the small bubbles are identified through the strengthened linkage mode, so that the accuracy of identifying effective bubbles is improved; in the second aspect, when calculating the gas leakage amount, the volume of the measuring cylinder is first quickly coarsely adjusted by the macroscopic control component, and then the volume of the measuring cylinder is finely adjusted by the microscopic control component, so that the gas pressure in the measuring cylinder is balanced with the gas pressure in the water collecting space, and the accuracy of calculating the gas leakage amount is improved. BRIEF DESCRIPTION OF DRAWINGS

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can also be obtained without creative labor based on these drawings.

[0018] Figure 1 A top view of the packer gas sealing performance detection device described in the embodiment of the present application; Figure 2 A structural schematic view of the packer gas sealing performance detection device described in the embodiment of the present application after removing the infrared sensing module; Figure 3 A sectional view of the packer gas sealing performance detection device described in the embodiment of the present application after removing the infrared sensing module; Figure 4 A sectional view of the packer gas sealing performance detection device described in the embodiment of the present application after removing the infrared sensing module; Figure 3 A local enlarged schematic view of B in the above figure; Figure 5 A connection schematic view of each component of the pipeline unit described in the embodiment of the present application; Figure 6 A sectional view of the infrared sensing module described in the embodiment of the present application; Figure 7 A control principle diagram of the packer gas sealing performance detection device described in the embodiment of the present application; Figure 8 A flow chart of the detection method of the packer gas sealing performance described in the embodiment of the present application; Figure 9 A flow chart of the method of the leakage measurement step described in the embodiment of the present application.

[0019] 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

[0020] 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.

[0021] 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.

[0022] 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 specification of this 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.

[0023] Please refer to Figures 1-7The embodiment of the application provides a packer air tightness detection device 100, the packer air tightness detection device 100 includes pipeline unit 110, bubble measuring unit 120, leakage measuring unit 130, air pressure detection unit 140, unit 150 to be measured and controller 160.Bubble measuring unit 120 includes visual camera 121 for obtaining visual data and infrared sensing module 122 for obtaining infrared data.Leakage measuring unit 130 includes measuring cylinder 131, macroscopic control component 132 and microscopic control component 133, macroscopic control component 132 is connected with measuring cylinder 131, and microscopic control component 133 fine tunes the volume of measuring cylinder 131.Air pressure detection unit 140 includes first air pressure sensor 141 for obtaining first air pressure value and second air pressure sensor 142 for obtaining second air pressure value.Unit 150 to be measured is used to place detection piece 200, and unit 150 to be measured is communicated with bubble measuring unit 120 and leakage measuring unit 130 respectively through pipeline unit 110.Controller 160 is electrically connected with visual camera 121, infrared sensing module 122, macroscopic control component 132, microscopic control component 133, first air pressure sensor 141 and second air pressure sensor 142 respectively.Exemplarily, the infrared sensing module 122 of the application adopts multiple groups of infrared emitting tubes 1221 and receiving tubes 1222 to form an array, and forms a blind area-free coverage in a detection area.The specific arrangement mode is that multiple groups of infrared sensors are linearly arranged along the horizontal direction and the vertical direction, the emitting end and the receiving end of each group of sensors are symmetrically distributed on the two sides of the bubble detection area A, the sensor spacing is less than or equal to 2 mm, so that the bubble can be captured by at least one group of sensors no matter where it appears in the area.In addition, a microlens diffusion sheet 1223 is additionally arranged at one end of the infrared emitting tube 1221, so that the infrared light uniformly covers the entire detection area with a divergence angle of about 120 degrees, avoiding local blind areas caused by light intensity concentration.Each infrared sensor independently outputs an electrical signal, and the control module simultaneously collects all channel data through a multi-channel ADC.Infrared light changes in energy due to the absorption, reflection and scattering of different media, and the molecular structure and density difference between bubbles and water bodies are very large, resulting in completely different effects of the two on specific wavelength infrared light, which is the fundamental reason why infrared sensors can distinguish bubbles from water bodies.In the bubble detection scene, the infrared sensor usually selects near-infrared waveband infrared light with a wavelength of 940 nm.In the absence of bubble generation, transmission is dominant, at this time, the water body molecules are dense and uniform, the infrared light can directly penetrate, only a small amount of energy is absorbed or reflected along the original direction by the water body, and there is no obvious scattering, so the signal strength is stable and close to the initial emission intensity.In the presence of bubble generation, scattering is dominant, and the loose structure of gas molecules will scatter irregularly, part of the light deviates from the original propagation direction and cannot be captured by the receiving end, resulting in a significant reduction in the infrared light energy obtained by the receiving end, so the signal strength suddenly decreases or appears pulse-like fluctuations.The leakage amount measuring unit 130 further comprises a temperature sensor 134 arranged in the measuring cylinder 131 for acquiring temperature data in the measuring cylinder 131 in real time.

[0024] The controller 160 is configured to apply a target pressure and a target temperature to the detection object 200 in the unit 150 to be detected, cross-verify the bubble recognition result according to the acquired visual data and infrared data, and determine that the detection object 200 is of the V0 grade if the bubble recognition result meets the grade determination condition, or perform the leakage amount measuring step if the bubble recognition result does not meet the grade determination condition.

[0025] The core innovation of the present application is as follows. First, when detecting bubbles, the visual camera 121 and the infrared sensing module 122 are coordinated and matched, the visual camera 121 is used to collect visual images of bubbles, and near-infrared light is used to confirm the generation of bubbles. The cross-verification of visual form verification and infrared signal positioning is beneficial to improve the accuracy of identifying effective bubbles. Second, the macro control assembly 132 and the micro control assembly 133 are coordinated and matched, and the volume of the measuring cylinder 131 is first roughly adjusted by the macro control assembly 132 when calculating the gas leakage amount, and then the volume of the measuring cylinder 131 is finely adjusted by the micro control assembly 133, so that the gas pressure in the measuring cylinder 131 is balanced with the gas pressure in the water collecting space 171, which is beneficial to improve the accuracy of calculating the gas leakage amount. Third, the current leakage amount change trend can be obtained based on the current leakage amount change data, and the future leakage amount can be predicted according to the current leakage amount change trend. That is, the packer detected by the detection device of the present application is not only qualified at present, but also guaranteed to be qualified in the future use cycle.

[0026] The leakage amount measuring step comprises: calculating a gas pressure difference value based on the first gas pressure value and the second gas pressure value, controlling the macro control assembly 132 to adjust the position of the measuring cylinder 131 so that the gas pressure difference value is within a first pressure difference range. The micro control assembly 133 is controlled to finely adjust the volume of the measuring cylinder 131 so that the gas pressure difference value is within a second pressure difference range. The gas leakage amount per unit time is calculated, and if the gas leakage amount is less than a leakage amount threshold, the detection object 200 is determined to be of the V1 grade, otherwise the detection object 200 is determined to be unqualified. Exemplarily, the detection object 200 is a packer. The first pressure difference range is set to be less than 0.5 Pa, and the second pressure difference range is set to be less than 0.1 Pa. In this embodiment, the unit time is set to be 15 minutes, and the unit time can be set according to specific requirements, for example, if the sealing performance of the packer is required to be higher, the unit time can be set to 20 minutes or 30 minutes.

[0027] Please refer to Figure 1 , Figure 2 andFigure 3In a possible implementation, the packer air tightness detection device 100 further comprises a box 170, the box 170 comprising a water collecting space 171, the measuring cylinder 131 being arranged in the water collecting space 171, the macroscopic regulation assembly 132 comprising a mounting frame 1321, a driving motor 1322, a screw rod 1323, a mounting block 1324, a mounting plate 1325, a spiral conduit 1326 and a guide rod 1327, the mounting frame 1321 being fixedly installed on the box 170, the driving motor 1322 being fixedly installed on the mounting frame 1321 and connected with the screw rod 1323, the screw rod 1323 being connected with the spiral conduit 1326, the mounting block 1324 and the mounting plate 1325 being respectively connected to two ends of the spiral conduit 1326, and the mounting block 1324 being connected with the measuring cylinder 131, and the guide rod 1327 having the mounting block 1324 and the mounting plate 1325 connected to two ends thereof. Exemplarily, the core function of the macroscopic regulation assembly 132 is to maintain the air pressure balance inside and outside the measuring cylinder 131, and to lay the foundation for the leakage measurement. Before the bubble detection, water needs to be added into the water collecting space 171, and the water amount is about half of the water collecting space 171. It can be understood that the box 170 is made of transparent material, and the visual camera 121 and the infrared sensing module 122 can obtain the data information of the bubbles by penetrating the box 170. Of course, in specific applications, a transparent window can also be provided. It should be noted that the measuring cylinder 131 is a hollow structure, and the bottom of the measuring cylinder 131 is not blocked, and the bottom of the measuring cylinder 131 is immersed into the water level of the water collecting space 171, that is, the volume of the measuring cylinder 131 containing the gas is determined by the space between the mounting block 1324 at the top of the measuring cylinder 131 and the water level at the bottom. The air pressure detection unit 140 collects the air pressure in the measuring cylinder 131 and the atmospheric pressure in the water collecting space 171 through two air pressure sensors, and when the air pressure needs to be balanced, the controller 160 sends an adjustment instruction to the macroscopic regulation assembly 132. At this time, the driving motor 1322 drives the screw rod 1323 to rotate, and the screw rod 1323 drives the mounting block 1324 fixed with the measuring cylinder 131 to vertically ascend and descend through the spiral conduit 1326: if the air pressure in the measuring cylinder 131 is higher than the atmospheric pressure, the driving motor 1322 is driven to rotate to drive the measuring cylinder 131 to ascend, so as to increase the volume of the measuring cylinder 131 to reduce the air pressure; if the air pressure in the measuring cylinder 131 is lower than the atmospheric pressure, the driving motor 1322 is driven to rotate in the opposite direction to drive the measuring cylinder 131 to descend, so as to reduce the volume to increase the air pressure, until the difference between the two is within the first pressure difference range. The adjustment process ensures that the measuring cylinder 131 is always in a stable air pressure state, avoids the calculation distortion of the leakage amount caused by the air pressure deviation, and is a prerequisite for the subsequent accurate measurement of the leakage amount.The guide rod 1327 in the macro-control assembly 132 cooperates with the lead screw 1323 and the spiral guide pipe 1326 to ensure stable movement of the measuring cylinder 131. The guide rod 1327 is parallel to the axis of the measuring cylinder 131, and can limit the movement of the mounting block 1324 only in the vertical direction, thereby avoiding horizontal deviation of the measuring cylinder 131 during lifting. If deviation occurs, it will cause deviation in the identification of the liquid level line by the image recognition assembly for monitoring the liquid level, and cause adjustment disorder. At the same time, the cooperation of the lead screw 1323 and the guide rod 1327 can make the lifting process of the measuring cylinder 131 smooth and without jamming and vibration, thereby avoiding false pressure difference caused by liquid level fluctuation in the box 170 due to vibration, and further ensuring the accuracy of the gas pressure balance adjustment.

[0028] Please refer to Figure 3 and Figure 4 In a possible implementation, a fine adjustment channel 1324A for placing the micro-control assembly 133 is formed on the mounting block 1324, the fine adjustment channel 1324A is in communication with the water collecting space 171, the micro-control assembly 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 arranged on the side of the piston 1332 away from the water collecting space 171, the fine adjustment channel 1324A is sealed by the piston 1332, and the micro-volume compensation module 1331 drives the piston 1332 to move in the fine adjustment channel 1324A. It should be noted that the mounting block 1324 is partially embedded in the measuring cylinder 131, and the mounting block 1324 is used to seal the upper end of the measuring cylinder 131. Therefore, the fine adjustment channel 1324A is in communication with the measuring cylinder 131, that is, the fine adjustment channel 1324A also belongs to a part of the volume of the measuring cylinder 131. Exemplarily, the fine adjustment channel 1324A is in a cylindrical shape, and the aperture in the axial direction of the fine adjustment channel 1324A is a fixed straight hole for facilitating calculation of the volume. The micro-volume compensation module 1331 is a piezoelectric ceramic, which has a nanoscale displacement output capability and can drive the piston 1332 to realize a micro displacement of 0.001 mm-0.01 mm in the fine adjustment channel 1324A. The macro-control assembly 132 in the application is used for large-scale volume adjustment, but cannot cover a micro displacement of less than 0.01 mm; the piezoelectric ceramic is responsible for micro volume adjustment. One of the innovations of the application is that the macro-control assembly 132 and the micro-control assembly 133 can be coordinated, the gas pressure difference is first adjusted to a range less than 0.5 Pa by the macro-control assembly 132, then the macro-control assembly 132 stops working, and then the gas pressure difference is adjusted to a range less than 0.1 Pa by the micro-control assembly 133. This can realize rapid adjustment of the volume and also realize nanoscale volume adjustment precision, thereby meeting the requirement for micro pressure difference control.

[0029] The leakage amount of the present application is indirectly calculated by measuring the displacement of the measuring cylinder 131 and the displacement of the piston 1332. Only when the air pressure in the measuring cylinder 131 is balanced with the atmospheric pressure, the two displacement amounts can be completely equivalent to the volume of the leaked gas. If the pressure difference is unbalanced, it will cause errors in the calculated leakage amount. In addition, the packer detection of the present application needs to be repeated in batches. If the pressure difference reference of each batch detection is inconsistent, the basic offset of the leakage amount calculation of each batch will be different. Even if the actual leakage amount is the same, the reference deviation will also cause differences in the calculation results, which cannot be judged through data comparison to determine the stability of the packer batch quality. By the synergistic regulation of the macro-regulation component 132 and the micro-regulation component 133, the pressure difference is stabilized in the second pressure difference range of 0.1 Pa or less, which can ensure that all batch detections are based on the same reference, which is conducive to further improving the accuracy of the device detection.

[0030] Please refer to Figure 3 and Figure 4 In a possible implementation, the macro-regulation component 132 further includes a first displacement sensor 1328 for obtaining the displacement amount of the measuring cylinder 131, and the micro-regulation component 133 further includes a second displacement sensor 1329 for obtaining the displacement amount of the piston 1332.

[0031] Please refer to Figure 3 、 Figure 4 and Figure 5 In a possible implementation, the pipeline unit 110 includes an air path 111, a first control valve 112, and a second control valve 113. The first control valve 112 is used to control the on-off between the water collecting space 171 and the unit to be detected 150, and the second control valve 113 is used to control the on-off between the water collecting space 171 and the measuring cylinder 131. The unit to be detected 150 is connected with a pressurizing system.

[0032] Please refer to Figure 3 、 Figure 4 and Figure 5 As shown in Figure 4 , the first displacement sensor 1328, the first air pressure sensor 141, and the temperature sensor 134 are arranged on the mounting block 1324, and the second displacement sensor 1329 is installed on the piston 1332. As Figure 5As shown, the measuring cylinder 131 is also connected with a pressure relief pipeline 117, and a third control valve 115 of the pressure relief pipeline 117 is arranged, and the third control valve 115 is used for controlling the opening and closing of the pressure relief pipeline 117, and when the leakage detection is completed, the third control valve 115 can be opened to release the gas in the measuring cylinder 131. The pipeline unit 110 further comprises a fourth control valve 116 arranged on the pipeline connecting the pressurizing system and the lower compression chamber 152, and used for controlling the opening and closing between the pressurizing system and the lower compression 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 respectively electrically connected with the controller 160.

[0033] Please refer to Figure 8 and Figure 9 A detection method of the gas sealing performance of the packer, applied to the packer gas sealing performance detection device 100, the method comprising: S1, placing the to-be-detected member 200 into the to-be-detected unit 150, and sealing the to-be-detected unit 150; exemplarily, the prepared to-be-detected member 200 is placed into the to-be-detected unit 150 under the cooperation of the loading machine. In this embodiment, the to-be-detected unit 150 is a kettle body, and two to-be-detected members 200 are placed into the kettle body, so that the to-be-detected unit 150 is divided into an upper compression chamber 151, a lower compression chamber 152 and a center chamber 153.

[0034] S2, applying a target pressure and a target temperature to the to-be-detected member 200 in the to-be-detected unit 150, and performing a setting operation on the to-be-detected member 200; exemplarily, after heating and pressurizing by the external heating device and the pressurizing system respectively, and reaching the target temperature and the target pressure and being stable, the setting operation is performed, which is mechanical setting or pressure setting. The gas output by the pressurizing system is nitrogen, on the one hand, the chemical inertness of nitrogen is suitable for high-pressure detection environment, which is conducive to eliminating safety risks, and on the other hand, the solubility of nitrogen in water is extremely low, so that after the leaked gas enters the water collection space 171 or the measuring cylinder 131, it is almost not dissolved in water, which is conducive to avoiding the distortion of the leakage calculation and improving the detection accuracy.

[0035] S3, obtaining a bubble recognition result according to the cross verification of the acquired visual data and infrared data double signals; S4, if the bubble recognition result meets the grade determination condition, determining that the to-be-detected member 200 is V0 grade; if the bubble recognition result does not meet the grade determination condition, executing a leakage measurement step; The leakage measurement step comprises: S41, calculating a gas pressure difference value through the first gas pressure value and the second gas pressure value, and controlling the macroscopic regulation and control assembly 132 to adjust the position of the measuring cylinder 131 so that the gas pressure difference value is within a first pressure difference range; S42, control the micro-adjusting assembly 133 to finely adjust the volume of the measuring cylinder 131, so that the air pressure difference value is in 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, determine that the to-be-detected piece 200 is V1 level, otherwise determine that the to-be-detected piece 200 is unqualified.

[0036] In a possible implementation, the bubble recognition result obtained by cross verification of the acquired visual data and infrared data includes: The visual camera 121 acquires images of the bubble detection area A in real time, performs binaryzation processing on the images, extracts bubble contours, and then performs feature matching to obtain real-time visual judgment results. Feature matching includes bubble circularity, area, contour regularity, etc. Illustratively, the real-time collected RGB image is subjected to Gaussian filtering to eliminate high-frequency noise caused by water particles, the RGB image is converted to a grayscale image, and then histogram equalization is performed to enhance the contrast. The ROI region is cropped to retain only part of the bubble detection area A, the algorithm automatically calculates the grayscale histogram of the ROI region, finds a threshold T that maximizes the inter-class variance between bubbles and water, and determines that pixels with a grayscale value less than T are suspected bubble regions and pixels with a grayscale value greater than or equal to T are water. All edges of the ROI region are extracted through Canny edge detection, and only the outermost contour is extracted using the external contour search mode. The minimum circumscribed rectangle area of each contour is calculated, and contours with an area less than 0.07 mm² are excluded to preliminarily filter out small impurities. Based on the three characteristics of bubble circularity, edge smoothness, and dynamic stability, non-bubble false contours are excluded, and contours that meet the above three criteria are marked as visual suspected bubbles.

[0037] The infrared sensing module 122 continuously emits near-infrared light to the bubble detection area A, and the receiving end collects real-time signal intensity. If the real-time signal intensity is less than the first signal threshold, the infrared sensing module 122 sends a suspected bubble infrared signal to the controller 160. Illustratively, the first signal threshold is defined as the real-time signal attenuation amplitude collected by a group of infrared sensors of the infrared sensing module 122 exceeding 20%, i.e., the real-time signal being less than 80% of the initial reference signal.

[0038] The controller 160 retrieves the visual judgment result of the same timestamp, and if the visual judgment result is suspected to have a bubble, it confirms that there is an effective bubble and records the timestamp of the effective bubble.

[0039] If the real-time signal strength collected by the infrared sensing module 122 is less than the second signal threshold, and the duration of the attenuation of the real-time signal exceeds the preset threshold time, the controller 160 sends an infrared low-intensity suspected signal and starts the enhanced linkage mode; or, if the image analysis result of the visual camera 121 is that there is a blurred outline, the controller 160 sends a visual suspected signal and starts the enhanced linkage mode; the enhanced linkage mode includes: obtaining the position coordinate area where the infrared low-intensity suspected signal appears; at least one of the following operations is performed on the visual camera 121: extending the exposure time, increasing the sampling density, enhancing the noise reduction, enabling the polarization filtering function, increasing the light input in the position coordinate area, and focusing on the position coordinate area; at least one of the following operations is performed on the infrared sensing module 122: optimizing the signal triggering threshold, increasing the sampling frequency, and improving the spatial mapping accuracy.

[0040] The real-time signal attenuation amplitude of a certain group or multiple groups of the infrared sensing module 122 to the pipe is 15%-20%, which is lower than the normal triggering threshold by 20%, and is defined as a low-intensity signal. The controller 160 sends an enhanced instruction to the visual camera 121, and only optimizes the parameters for the infrared suspected area, without global adjustment to avoid excessive exposure of the overall image. Or, if the image analysis result of the visual camera 121 is that there is a blurred outline, the enhanced linkage mode is also started, and the definition of the blurred outline is that the circularity of the obtained bubble image is within the range of 0.6-0.8, and the area is within the range of 0.03-0.07 mm². This area range corresponds to a small bubble or a disturbance. The outline edge of the visual camera 121 is easily distorted by water noise and light fluctuations at this scale, resulting in parameter measurement deviation, so the visual signal reliability is insufficient, and therefore the enhanced linkage mode needs to be started again for verification. The specific adjustment items are as follows: increase the light input in the position coordinate area to make the gray difference of 0.1-0.3 mm small bubbles more obvious, and increase the bubble gray value by 15-25 units. Extend the exposure time to improve the light signal collection of the small bubble edge and avoid outline blur caused by too fast shutter. Increase the sampling density to capture the continuous motion trajectory of the small bubble and avoid frame loss. Based on the spatial coordinates of the infrared signal mapping, lock the focus point in this area to avoid local defocus caused by global focus. Enhance the noise reduction to 7x7 bilateral filtering, and enable the polarization filtering function to offset the high-frequency noise points caused by exposure compensation and retain the real bubble edge. The conventional noise reduction is 5x5 Gaussian filtering, and the polarization filtering function is not enabled.

[0041] The optimization of the signal triggering threshold specifically includes: the normal mode triggering threshold is signal attenuation ≥ 20%, and the enhanced mode is adjusted to signal attenuation ≥ 15%, which adapts to the weak scattering signal caused by microbubbles. The sampling and detection parameter adjustment specifically includes: the sampling frequency is increased from 100 Hz to 200 Hz to capture the signal blocked by microbubbles in an instant, the detection time is extended from 40 ms single frame verification to 250 ms continuous 50 frame verification to accumulate the signal attenuation trend, and if 30 frames out of 50 frames meet the attenuation ≥ 15% condition, it is determined as a continuous low-intensity suspected signal to avoid false triggering caused by transient noise. The improvement of spatial mapping accuracy specifically includes: the coordinate mapping error between the infrared channel and the visual pixel is reduced from ± 0.05 mm to ± 0.03 mm to ensure the accurate alignment of the position coordinate area and the visual ROI area, and to avoid signal mismatch caused by spatial misplacement.

[0042] The timestamp synchronization accuracy is improved from ± 0.01 s to ± 0.005 s to ensure that the visual frame and the infrared sampling point are completely aligned in time. The Euclidean distance d between the center of the infrared suspected area and the center of the visual blur profile is ≤ 0.8 mm, which adapts to the position deviation of microbubbles. The visual end accumulates the blur profile features of 3 consecutive frames, if there are 3 frames with circularity 0.6-0.8, area 0.03-0.07 mm², and center coordinate deviation ≤ 0.1 mm / frame, which meets the bubble rising motion law, it is marked as a visual potential bubble. The infrared end accumulates the signal attenuation data of 30 consecutive frames, if the attenuation amplitude is stable at 15%-20% without mutation, it is marked as an infrared confirmed suspected signal. If both the visual potential bubble and the infrared confirmed suspected signal are met, it is determined as an effective microbubble. If only one condition is met, for example, the infrared continuous low intensity but no visual profile, it is determined as an interference signal, the data is recorded but not included in the V0 level judgment count.

[0043] The enhanced linkage mode is a temporary triggering state, and the controller 160 automatically exits according to the following logic to restore the normal detection parameters and ensure the detection efficiency: the first kind is normal exit, when it is determined as an effective microbubble, the controller 160 maintains the current parameters to complete 1 frame of data storage, then restores the normal settings of the camera and infrared module within 0.1 seconds, and continues to execute the regular double signal cross verification. The duration of the enhanced linkage mode is set to 3 seconds, if the combined conditions of visual potential bubble and infrared confirmed suspected signal are not met within 3 seconds, the normal parameters are automatically restored; within 10 seconds after exiting, if the enhanced condition is triggered again, it is only allowed to start once to avoid parameter fluctuations caused by frequent switching.

[0044] Another innovative point of the technical solution of the present application is to solve the identification problem of micro-bubbles. On the one hand, the limitation of single signal identification is made up through double signal cooperative verification. The infrared sensing module 122 forms a non-blind area coverage with multiple groups of paired tube arrays, utilizes the scattering characteristics of micro-bubbles to near-infrared light, and captures the weak signal that is difficult to be identified by traditional single infrared. The visual camera 121 distinguishes micro-bubbles from static impurities through shape and dynamic multi-feature matching. The two cooperate with each other, the infrared provides suspected area positioning, and the vision provides shape verification, which in principle avoids the problems of missing weak signals by single infrared and misjudgment of fuzzy outline by single vision, and ensures that micro-bubbles are not missed and misjudged. On the other hand, through visual parameter directional optimization, the shape characteristics of micro-bubbles are adapted. In view of the shape characteristics of micro-bubbles, such as unclear outline and irregular edge, the visual processing breaks through the limitation of traditional fixed threshold in principle through adaptive segmentation algorithm to dynamically adapt to light changes and avoid outline loss caused by light fluctuation. The shape judgment threshold is relaxed to adapt to the non-standard shape of micro-bubbles. In the linkage mode, the exposure, focusing and filtering parameters of the infrared suspected area are adjusted to improve the gray difference between bubbles and water body in principle and eliminate reflection interference, so that the outline of micro-bubbles is clearly separated from the background, and the problem of shape blur that cannot be identified by traditional vision is solved. Thirdly, starting from the signal correlation principle, the timestamps of visual and infrared signals are accurately synchronized to ensure that both respond to the same micro-bubble and avoid missing judgment caused by time and space misplacement. Through accurate mapping of spatial coordinates, the infrared suspected area is aligned with the visual detection area to avoid signal mismatch caused by area deviation. Finally, through multi-frame signal accumulation verification, accidental interference such as reflection and noise is excluded in principle to ensure that the identification result is not interference signal but real micro-bubble, which greatly improves the identification reliability.

[0045] In a possible implementation, if the bubble identification result meets the level judgment condition, the to-be-detected piece 200 is determined to be V0 level; if the bubble identification result does not meet the level judgment condition, a leakage measurement step is performed, which includes: If no effective bubble appears within a first preset time at the beginning of detection, the to-be-detected piece 200 is determined to be V0 level. In this embodiment, the first preset time is 15 minutes.

[0046] If one effective bubble appears within a first preset time at the beginning of detection, the detection time is automatically extended, the time is counted from the time when the first effective bubble appears, and the second bubble is waited. If the interval time between the second effective bubble and the first effective bubble is greater than a second preset time, the to-be-detected piece 200 is determined to be V0 level; if the interval time between the second effective bubble and the first effective bubble does not exceed the second preset time, a leakage measurement step is performed. In this embodiment, the second preset time is 15 minutes.

[0047] The calculation formula of the gas leakage amount is: In the formula: represents the cross-sectional area of the inner cavity of the measuring cylinder 131; represents the displacement amount of the measuring cylinder 131 from the start to the end of the leakage amount detection; represents the cross-sectional area of the fine adjustment channel 1324A; represents the displacement amount of the piston 1332 from the start to the end of the leakage amount detection.

[0048] In one possible implementation, the method further comprises: calculating the continuous leakage amount according to the gas leakage amount calculation formula, storing the historical data of the continuous leakage amount, extracting the leakage amount change slope, the temperature sensitivity coefficient and the pressure sensitivity coefficient features, predicting the future leakage amount change trend of the packer based on the time series algorithm and the working condition correlation model, and outputting the prediction determination result of the gas sealing performance of the packer.

[0049] The following is the calculation process of the future leakage amount change trend: The instantaneous leakage amount calculation formula is as follows: In the formula, represents the instantaneous leakage amount in a certain collection period, represents the initial volume of the measuring cylinder 131, represents the pressure change amount of the measuring cylinder 131 in the collection period, collected by the first gas pressure sensor 141, represents the standard state absolute temperature 298.15K; represents the standard state atmospheric pressure 101.325kPa; represents the absolute temperature in the measuring cylinder 131, collected by the temperature sensor 134 in the measuring cylinder 131. The volume of the measuring cylinder 131 is fixed, and the leakage gas only causes the pressure in the cylinder to rise after entering. By the ideal gas state equation, the pressure change amount is converted into the volume of the leakage gas, eliminating the influence of the constant volume.

[0050] The pressure change slope calculation formula is as follows: In the formula, represents the average pressure change slope of the measuring cylinder 131 in 24 hours, which can reflect the pressure growth rate caused by leakage; represents the total pressure change amount of the measuring cylinder 131 in 24 hours, continuously collected by the first gas pressure sensor 141; represents the time period. ​

[0051] The temperature sensitivity coefficient calculation formula is as follows: The change amount of the pressure in the cylinder when the temperature of the measuring cylinder 131 changes by 1°C is used to correct the false change of the pressure caused by the temperature; represents the change amount of the pressure in the cylinder when only the temperature changes; represents the temperature change amount of the measuring cylinder 131, which is collected by the temperature sensor 134 in the measuring cylinder 131.

[0052] The future measuring cylinder 131 pressure prediction formula is as follows: In the formula, represents the pressure in the measuring cylinder 131 at the future moment; represents the pressure value in the measuring cylinder 131 at the prediction starting moment, that is, the real-time value of the first air pressure sensor 141; represents the future prediction period; represents the temperature change amount of the cylinder in the future prediction period.

[0053] The future leakage amount calculation formula is as follows: In the formula, represents the 15-minute leakage amount in the future prediction period, which is used for V1 level determination in a certain time period in the future; 15 / 60 represents the time conversion coefficient; represents the temperature of the measuring cylinder 131 in the future prediction period.

[0054] First, the pressure in the future measuring cylinder 131 is predicted, the predicted pressure difference value is converted into a 15-minute leakage amount, compared with the document V1 level threshold value, and it is determined whether it is qualified.

[0055] The working process of the packer air tightness detection device 100 is as follows: The to-be-tested piece 200 is placed in the to-be-tested unit 150 under the cooperation of the loading machine, and a test casing is lowered into the to-be-tested unit 150; if it is necessary to simulate the isolation scene of multiple storage zones in the well, two to-be-tested pieces 200 can be placed, so that the to-be-tested unit 150 is divided into independent upper compression cavities 151, lower compression cavities 152 and central cavities 153. The hatch of the to-be-tested unit 150 is closed and sealed, the first control valve 112 and the second control valve 113 are closed, and it is ensured that the to-be-tested unit 150 is temporarily not connected with other components, so as to avoid the interference of initial leakage. The controller 160 sends instructions to the pressurizing system connected to the to-be-tested unit 150, the temperature in the to-be-tested unit 150 is raised to the target temperature of the test through the heating device, and the upper compression cavity 151 or the lower compression cavity 152 in the to-be-tested unit 150 is pressurized to the target pressure through the pressurizing system. If the pressurizing system is connected with the lower compression cavity 152, the water collection space 171 and the measuring cylinder 131 are connected with the upper compression cavity 151 respectively, and if the pressurizing system is connected with the upper compression cavity 151, the water collection space 171 and the measuring cylinder 131 are connected with the lower compression cavity 152 respectively; the target temperature and the target pressure are set according to actual needs, and the purpose is to simulate the downhole working environment of the packer. The controller 160 receives the temperature and pressure data fed back by the pressurizing system in real time, and if the fluctuation is ≤±0.5℃ within 30 minutes, it indicates that the temperature is stable, and if the fluctuation is ≤±0.1MPa within 30 minutes, it indicates that the pressure is stable. After the temperature and the pressure are stable, the temperature and pressure control are stopped, and the downhole working condition simulation is completed. The controller 160 controls the pressurizing system to perform a setting operation: if it is mechanical setting, an instruction is output to the force loading device to apply a setting force, and if it is pressure setting, the setting cavity of the to-be-tested piece 200 is pressurized. After setting, the upper compression cavity 151, the lower compression cavity 152 and the central cavity 153 are not connected with each other. The pipeline unit 110 further includes a leakage gas pipe 114, the leakage gas pipe 114 is inserted to a position with a water depth of about 5mm, the leakage gas pipe 114 is connected with the gas pipeline 111, when there is leakage gas in the upper compression cavity 151, the leakage gas enters the water in the water collection space 171 through the gas pipeline 111 and the leakage gas pipe 114, so as to generate bubbles. The controller 160 controls the first control valve 112 of the pipeline unit 110 to be opened, and the second control valve 113 to be kept closed, so that the upper compression cavity 151 (taking the example that the pressurizing system is connected with the lower compression cavity 152) of the to-be-tested unit 150 is connected with the water collection space 171; if there is leakage gas in the upper compression cavity 151, the bubbles in the bubble detection area A of the water collection space 171 can be detected through the pipeline unit 110.

[0056] In the bubble detection stage, the visual camera 121 acquires images of the bubble detection area A in real time, the controller 160 performs binaryzation processing on the images, extracts the contour features in the images, and matches them with the bubble template to generate real-time visual judgment results, which include two results: suspected bubble and no bubble. The infrared sensing module 122 continuously emits 940 nm near-infrared light to the bubble detection area A, and the receiving end acquires the signal intensity in real time; if there is a bubble, the bubble will scatter the near-infrared light, making the signal intensity less than the first signal threshold, for example, the first signal threshold can be set to 80% of the initial reference signal. The infrared sensing module 122 immediately sends a suspected bubble infrared signal to the controller 160. It can be understood that before the bubble detection is performed, an initial reference signal of the near-infrared light in the bubble detection area A without bubble generation needs to be determined first. The visual judgment result and the infrared signal of the same timestamp are called, and if both are suspected bubbles, it is confirmed that there is an effective bubble, and the timestamp of the effective bubble is recorded; if only a single signal is suspected bubble, it is determined as interference, such as water impurities, light reflection, etc., and is not recorded as an effective bubble. If no effective bubble appears within 15 minutes, the controller 160 directly determines that the detected piece 200 is V0 grade, closes the first control valve 112, and opens the pressure relief valve of the detected unit 150 to complete the detection. If one effective bubble appears within 15 minutes, the controller 160 automatically extends the detection time, and the timing starts from the generation time of the first effective bubble; if the interval time between the second effective bubble and the first one exceeds 15 minutes, it is still determined as V0 grade; if the interval time does not exceed 15 minutes, it is determined that the V0 grade does not meet the requirements, and enters the V1 grade leakage detection stage.

[0057] In the leakage amount detection stage, the controller 160 closes the first control valve 112 of the pipeline unit 110 and opens the second control valve 113, so that the upper compression chamber 151 communicates with the measuring cylinder 131; at the same time, other passages of the water collecting space 171 are closed to ensure that the leakage gas only enters the measuring cylinder 131. The first air pressure sensor 141 collects the first air pressure value in the measuring cylinder 131 in real time, and the second air pressure sensor 142 collects the second air pressure value of the atmospheric environment. The controller 160 calculates the air pressure difference ΔP = | first air pressure value-second air pressure value | every 0.1 second. During the detection of the leakage amount, if the upper compression chamber 151 has leakage gas, the leakage gas will enter the measuring cylinder 131, causing the air pressure in the measuring cylinder 131 to rise and the water level in the measuring cylinder 131 to drop. The gas leakage amount in a unit of time (15 minutes in this embodiment) is collected, and the timing starts from the beginning of collecting the leakage gas. After 15 minutes, the second control valve 113 is closed, and the gas leakage amount is calculated. First, the initial position L0 of the measuring cylinder 131 and the initial position D0 of the piston 1332 are collected by the first displacement sensor 1328 and the second displacement sensor 1329. The controller 160 sends instructions to the drive motor 1322 of the macroscopic regulation assembly 132, which drives the screw 1323 to rotate. The screw 1323 drives the measuring cylinder 131 to vertically rise along the guide rod 1327 through the spiral guide pipe 1326. During the rising of the measuring cylinder 131, the distance between the top of the measuring cylinder 131 and the horizontal plane becomes larger and larger, causing the volume of the measuring cylinder 131 to increase, and the air pressure in the measuring cylinder 131 to gradually decrease. The first displacement sensor 1328 collects the initial position and real-time position of the measuring cylinder 131 in real time and feeds back to the controller 160. When the controller 160 detects that ΔP < 0.5 Pa, the drive motor 1322 is controlled to stop rotating, and the macroscopic regulation assembly 132 is coarsely adjusted. At this time, the air pressure in the measuring cylinder 131 is preliminarily close to the atmospheric pressure. The controller 160 sends instructions to the micro-volume compensation module 1331 of the microscopic regulation assembly 133, and the piezoelectric ceramic drives the piston 1332 to move slightly in the fine adjustment channel 1324A of the mounting block 1324; for example, if ΔP = 0.3 Pa is still higher than the upper limit of the second pressure difference range, the piezoelectric ceramic drives the piston 1332 to move away from the water collecting space 171, increasing the total volume of the fine adjustment channel 1324A and the measuring cylinder 131, and further reducing the air pressure in the measuring cylinder 131. The second displacement sensor 1329 collects the initial position and real-time position of the piston 1332 in real time and feeds back to the controller 160; when the controller 160 detects that ΔP < 0.1 Pa, the piezoelectric ceramic is controlled to stop moving, ensuring that the air pressure in the measuring cylinder 131 is completely balanced with the atmospheric pressure, providing a unified reference for the leakage amount 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 obtains the cross-sectional area S1 of the inner cavity of the measuring cylinder 131, the cross-sectional area S2 of the fine adjustment channel 1324A, the displacement amount L of the measuring cylinder 131 is L=L1-L0, the displacement amount D of the piston 1332 is D=D1-D0, and finally the leakage amount is S1*L+S2*D. If the calculated 15-minute leakage amount is <20 cm³, the controller 160 determines that the to-be-detected piece 200 is of V1 grade; if ≥20 cm³, it is determined that the to-be-detected piece 200 is unqualified.

[0058] In the continuous measurement and trend prediction stage, the controller 160 sets a continuous acquisition period (such as 1 acquisition per 1 hour), repeats the macroscopic coarse adjustment, microscopic fine adjustment, and displacement acquisition process, calculates the instantaneous leakage amount in each acquisition period, and converts the data to the volume at standard state, i.e., 25°C and 101.325 kPa, to avoid data distortion caused by temperature and pressure fluctuations. The data storage module is electrically connected with the controller 160, and the data storage module is used to store the historical data of continuous measurement, including time stamp, instantaneous leakage amount at standard state, L, D, first gas pressure value, second gas pressure value, temperature and pressure of the to-be-detected unit 150. The controller 160 extracts feature parameters from the historical data, including leakage amount change slope, temperature sensitivity coefficient, and pressure sensitivity coefficient. The leakage amount change slope is defined as the slope of the trend line of the average leakage amount per 24 hours fitted by linear regression. The temperature sensitivity coefficient is defined as the leakage amount change value when the temperature of the to-be-detected unit 150 changes by 1°C. The pressure sensitivity coefficient is defined as the leakage amount change value when the pressure of the to-be-detected unit 150 changes by 1 MPa. The controller 160 calls the time series algorithm module built-in the data storage module to predict the leakage amount base value in the next 24 hours, 48 hours, and 72 hours. The working condition correlation model module is called to calculate the working condition correction amount according to the target temperature change amount and the target pressure change amount in the prediction period, and the correction amount = temperature sensitivity coefficient x temperature change amount + pressure sensitivity coefficient x pressure change amount. The controller 160 takes the base value and the correction amount as the future predicted leakage amount. For example, a to-be-detected piece 200 needs to work underground for 72 hours and requires to reach V1 grade, then the leakage amount after 72 hours can be predicted through the change trend of the leakage amount. If the predicted result still meets the requirements of V1 grade, if not, the to-be-detected piece 200 cannot complete the work.

[0059] After the detection is completed, the to-be-detected unit 150 and the measuring cylinder 131 are depressurized, the drive motor 1322 of the macroscopic control assembly 132 is reversed to drive the measuring cylinder 131 to descend to the initial position, and the piezoelectric ceramic driven piston 1332 of the microscopic control assembly 133 is reset to restore the volume of the fine adjustment channel 1324A to the initial value.

[0060] The above embodiments only express several implementation manners of the present application, the description is more specific and detailed, but cannot be understood as the limitation of the patent application scope. It should be pointed out that for ordinary skilled in the art, without departing from the concept of the present application, several modifications and improvements can be made, which all belong to the protection scope of the present application. Therefore, the protection scope of the present application patent should be subject to the appended claims.

Claims

1. A device for detecting the gas tightness of a packer, characterized in that, The device comprises: a pipeline unit; a bubble measuring unit comprising a visual camera for acquiring visual data and an infrared sensing module for acquiring infrared data; a leakage amount measuring unit comprising a measuring cylinder, a macroscopic regulating component connected with the measuring cylinder, and a microscopic regulating component for fine-tuning the volume of the measuring cylinder; an air pressure detecting unit comprising a first air pressure sensor for acquiring a first air pressure value and a second air pressure sensor for acquiring a second air pressure value; a unit to be tested for placing a piece to be tested, which is in communication with the bubble measuring unit and the leakage amount measuring unit through the pipeline unit; a controller electrically connected with the visual camera, the infrared sensing module, the macroscopic regulating component, the microscopic regulating component, the first air pressure sensor, and the second air pressure sensor; the controller is configured to apply a target pressure and a target temperature to the piece to be tested in the unit to be tested, cross-verify the bubble recognition result according to the acquired visual data and infrared data, and determine that the piece to be tested is of V0 grade if the bubble recognition result meets the grade determination condition; if the bubble recognition result does not meet the grade determination condition, perform a leakage amount measuring step; the leakage amount measuring step comprises: calculating an air pressure difference value from the first air pressure value and the second air pressure value, and controlling the macroscopic regulating component to adjust the position of the measuring cylinder so that the air pressure difference value is within a first pressure difference range; controlling the microscopic regulating component to fine-tune the volume of the measuring cylinder so that the air pressure difference value is within a second pressure difference range; calculating the gas leakage amount per unit time, and determining that the piece to be tested is of V1 grade if the gas leakage amount is less than a leakage amount threshold, otherwise determining that the piece to be tested is unqualified.

2. The device of claim 1, wherein, The device further comprises a box, the box comprises a water collecting space, the measuring cylinder is arranged in the water collecting space, the macroscopic regulating component comprises a mounting frame, a driving motor, a lead screw, a mounting block, a mounting plate, a spiral conduit, and a guide rod, the mounting frame is fixedly installed on the box, the driving motor is fixedly installed on the mounting frame and connected with the lead screw, the lead screw is connected with the spiral conduit, the mounting block and the mounting plate are respectively connected to two ends of the spiral conduit, and the mounting block is connected with the measuring cylinder, and the guide rod is connected with the mounting block and the mounting plate at two ends.

3. The device of claim 2, wherein, A fine-tuning channel for placing the microscopic regulating component is formed on the mounting block, the fine-tuning channel is in communication with the water collecting space, the microscopic regulating component comprises a micro-volume compensation module and a piston, the micro-volume compensation module is connected with the piston, and the micro-volume compensation module is arranged on the side of the piston away from the water collecting space, the fine-tuning channel is sealed by the piston, and the micro-volume compensation module drives the piston to move in the fine-tuning channel.

4. The device of claim 3, wherein, The macroscopic regulating component further comprises a first displacement sensor for acquiring the displacement of the measuring cylinder, and the microscopic regulating component further comprises a second displacement sensor for acquiring the displacement of the piston.

5. The device of claim 2, wherein, The pipeline unit comprises an air path, a first control valve and a second control valve, the first control valve is used for controlling the on-off between the water collecting space and the unit to be tested, and the second control valve is used for controlling the on-off between the water collecting space and the measuring cylinder, and the unit to be tested is connected with a pressurizing system.

6. A method for detecting the gas sealing performance of a packer, applied to the packer gas sealing performance detection device of any one of claims 1-5, characterized in that, The method comprises: S1, placing the detection object into the unit to be tested, and sealing the unit to be tested; S2, applying a target pressure and a target temperature to the detection object in the unit to be tested, and performing a setting operation on the detection object; S3, obtaining a bubble recognition result according to cross verification of the acquired visual data and infrared data double signals; S4, if the bubble recognition result meets the grade determination condition, determining that the detection object is of V0 grade; if the bubble recognition result does not meet the grade determination condition, performing a leakage amount measurement step; The leakage amount measurement step comprises: S41, calculating a gas pressure difference value through a first gas pressure value and a second gas pressure value, and controlling the macroscopic control assembly to adjust the position of the measuring cylinder so that the gas pressure difference value is within a first pressure difference range; S42, controlling the microscopic control assembly to finely adjust the volume of the measuring cylinder so that the gas pressure difference value is within a second pressure difference range; S43, calculating the gas leakage amount per unit time, and if the gas leakage amount is less than a leakage amount threshold value, determining that the detection object is of V1 grade, otherwise determining that the detection object is unqualified.

7. The method of claim 6, wherein the method further comprises, The bubble recognition result obtained according to cross verification of the acquired visual data and infrared data double signals comprises: The visual camera acquires images of the bubble detection area in real time, performs binaryzation processing on the images, extracts bubble contours, and then performs feature matching to obtain a real-time visual judgment result; The infrared sensing module continuously emits near-infrared light to the bubble detection area, and the receiving end collects real-time signal intensity; if the real-time signal intensity is less than a first signal threshold value, the infrared sensing module sends a suspected bubble infrared signal to the controller; The controller calls the visual judgment result of the same time stamp, and if the visual judgment result is suspected to have a bubble, it is confirmed that there is an effective bubble, and the time stamp of the effective bubble is recorded.

8. The method of claim 7, wherein, If the real-time signal intensity collected by the infrared sensing module is less than a second signal threshold value, and the decay duration of the real-time signal exceeds a preset threshold time, the controller sends an infrared low-intensity suspected signal and starts an intensive linkage mode; or, the image analysis result of the visual camera is that there is a fuzzy contour, the controller sends a visual suspected signal and starts the intensive linkage mode; The intensive linkage mode comprises: acquiring the position coordinate area of the infrared low-intensity suspected signal; performing at least one of the following operations on the visual camera: prolonging the exposure time, increasing the sampling density, enhancing the noise reduction, performing polarization filtering, increasing the light amount of the position coordinate area, and performing spot focusing on the position coordinate area; performing at least one of the following operations on the infrared sensing module: optimizing the signal trigger threshold value, increasing the sampling frequency, and improving the spatial mapping accuracy.

9. The method of claim 6, wherein, If the bubble recognition result meets the grade determination condition, the detection object is determined to be of V0 grade. If the bubble recognition result does not satisfy the grade determination condition, a leakage amount measurement step is performed, comprising: If no valid bubble appears within a first preset time after detection starts, the piece to be detected is determined as V0 grade; If one valid bubble appears within the first preset time after detection starts, the detection time is automatically extended, the time from the appearance of the first valid bubble is counted, and the second bubble is waited for. If the interval time between the second valid bubble and the first valid bubble is greater than a second preset time, the piece to be detected is determined as V0 grade. If the interval time between the second valid bubble and the first valid bubble does not exceed the second preset time, the leakage amount measurement step is performed.

10. The method of claim 6, wherein, The calculation formula of the gas leakage amount is: In the formula, P is the pressure of the gas, V is the volume of the gas, and t is the time. A represents the cross-sectional area of the inner cavity of the measuring cylinder; represents the displacement amount of the measuring cylinder from the start to the end of the leakage amount detection; This represents the cross-sectional area of ​​the fine-tuning channel; represents the displacement amount of the piston from the start to the end of the leakage amount detection.

Images