A Sealing Detection Method and System for a Protective Device

Abstract

This application relates to the technical field of airtightness detection, and particularly to an airtightness detection method and system for protective equipment. This application creates a non-pressure-difference environment inside and outside the protective equipment to be detected, sets an ultrasonic transmitting device inside and a receiving device outside; uses the transmitting device to emit ultrasonic waves, and the receiving device captures and records ultrasonic signals from leakage points through ultrasonic imaging technology, and then determines the number and location of leakage points; for each detected punctiform leakage point, according to the sound pressure level of the ultrasonic signal and the distance between the imaging device and the leakage point, the leakage aperture size is estimated through the first formula, and then according to the estimated leakage aperture size, the air leakage volume under the flow method test pressure is calculated through the second formula, and compared with the preset qualified index to judge whether it meets the requirements. Compared with the traditional flow method, it has higher efficiency, can accurately locate the position of the leakage point, and is easy to operate, thus helping to improve the reliability and efficiency of the airtightness detection of protective equipment.

Description

Technical Field

[0001] The present application relates to the technical field of airtightness detection, and particularly to an airtightness detection method and system for protective equipment. Background Art

[0002] With the development of society and the improvement of safety awareness, the airtight performance of protective equipment and facilities in civil air defense projects has become one of the important factors to ensure safety. Especially in the case of war or natural disasters, the airtight performance of civil air defense projects is directly related to the lives of people. Therefore, it is crucial to develop an efficient and reliable airtight performance detection method.

[0003] Currently, for the airtight performance detection of protective equipment and facilities in civil air defense projects, the commonly used method is the "flow method". This method seals the back side of the door frame wall of the civil air defense door to be detected at the construction site, then inflates and pressurizes, and detects the air leakage volume to evaluate the airtight performance. However, this method has some limitations.

[0004] The airtight performance detection by the flow method takes a long time. Usually, it takes 1 - 2 hours to detect a single-leaf civil air defense door. When detecting large-sized double-leaf civil air defense doors, it is difficult to form an airtight chamber. In addition, the flow method can only quantitatively test the air leakage volume and cannot know the specific location of the air leakage point, which poses a certain difficulty in dealing with the situation after finding that the airtight performance is unqualified. This situation needs to be further improved. Summary of the Invention

[0005] In order to solve the problems of low detection efficiency and inability to accurately locate leakage points in the prior art, the present application provides an airtightness detection method and system for protective equipment, adopting the following technical solutions:

[0006] In the first aspect, the present application provides an airtightness detection method for protective equipment, including the following steps:

[0007] Set an ultrasonic transmitting device inside the protective equipment to be detected, configure an ultrasonic receiving device outside, and make the inside and outside of the protective equipment form a non-pressure-difference environment;

[0008] Use the ultrasonic transmitting device to emit ultrasonic waves inside the protective equipment, and use the ultrasonic receiving device to capture and record the ultrasonic signals from the air leakage points through ultrasonic imaging technology to determine the number and location of the leakage points;

[0009] For each detected dot-shaped leakage point, estimate the leakage aperture size according to the sound pressure level of the ultrasonic signal and the distance between the imaging device and the leakage point through the first formula;

[0010] According to the estimated leakage aperture size, calculate the air leakage volume at the corresponding test pressure of the flow method through the second formula, and compare it with the preset qualified index to determine whether it meets the requirements.

[0011] By adopting the above technical solution, in order to overcome the problems of long time consumption, complex operation and inability to accurately locate the leakage point in the existing flow method for airtight performance detection, the present application provides a method for detecting the airtightness of a protective device, forming a non-pressure-difference environment inside and outside the protective device to be detected, setting an ultrasonic transmitting device inside and a receiving device outside; using the transmitting device to emit ultrasonic waves, and using the receiving device to capture and record the ultrasonic signals from the leakage point through ultrasonic imaging technology to determine the number and location of the leakage points; for each detected punctiform leakage point, estimate the leakage aperture size according to the sound pressure level of the ultrasonic signal and the distance between the imaging device and the leakage point through the first formula, and then calculate the air leakage volume at the test pressure of the flow method through the second formula according to the estimated leakage aperture size, and compare it with the preset qualified index to determine whether it meets the requirements. Compared with the traditional flow method, the detection efficiency is higher, the location of the leakage point can be accurately located, and the operation is simpler, thus helping to improve the reliability and efficiency of the airtightness detection of the protective device.

[0012] Optionally, after estimating the leakage aperture size through the first formula, the method further includes the following steps:

[0013] Determine the obvious leakage points according to the estimated leakage aperture size and the shape of the leakage point;

[0014] Temporarily block the detected obvious leakage points and perform ultrasonic detection again until there are no obvious leakage points.

[0015] By adopting the above technical solution, due to the problem that a large leakage aperture will cause a large amount of air leakage and affect the detection accuracy, the present application first determines the obvious large-aperture leakage points according to the leakage aperture size and the shape of the leakage point; then temporarily blocks these obvious leakage points and repeats the ultrasonic detection until there are no obvious leakage points. By blocking the large-aperture leakage points first, the air leakage volume can be effectively reduced and the detection accuracy of subsequent small-aperture leakage points can be improved; at the same time, the operation is simple and does not affect the overall detection process, so the reliability and efficiency of the airtightness detection can be further improved.

[0016] Optionally, use the ultrasonic transmitting device to emit ultrasonic waves inside the protective device, and use the ultrasonic receiving device to capture and record the ultrasonic signals from the air leakage point through ultrasonic imaging technology to determine the number and location of the leakage points, which specifically includes the following steps:

[0017] An ultrasonic transmitting device is used to transmit ultrasonic waves inside the protective equipment. An ultrasonic receiving device is utilized to capture and record ultrasonic signals from the air leakage points through ultrasonic imaging technology. According to the ultrasonic signals, a sound level spectrum is generated.

[0018] Based on the sound level spectrum, a sound distribution image is calculated and the sound distribution image is superimposed on the actual scene image to obtain a superimposed image.

[0019] The positions of the leakage points are identified from the superimposed image, and the number and position coordinates of the leakage points are recorded.

[0020] By adopting the above technical solution, in this application, first, an ultrasonic transmitting device inside is used to transmit ultrasonic waves, and an external receiving device is utilized to capture and record ultrasonic signals from the leakage points through ultrasonic imaging technology. A sound level spectrum is generated according to these signals. Then, based on the obtained sound level spectrum, a sound distribution image in space is calculated, and this sound distribution image is superimposed on the image of the actual detected scene to obtain a superimposed comprehensive image. Finally, the specific position coordinates of each leakage point are accurately identified from this superimposed image and recorded, which can intuitively and accurately display the position distribution of all leakage points, greatly improving the reliability and accuracy of leakage point identification.

[0021] Optionally, according to the estimated leakage aperture size, the air leakage volume under the corresponding test pressure of the flow method is calculated through a second formula, and compared with a preset qualified index to determine whether it meets the requirements. The specific steps are as follows:

[0022] According to the estimated leakage aperture size of each point-like leakage aperture, the air leakage volume under the corresponding test pressure of the flow method is calculated through a second formula.

[0023] According to the air leakage volume of each point-like leakage aperture, an estimated value of the cumulative air leakage volume of all point-like leakage apertures is obtained.

[0024] The estimated value of the cumulative air leakage volume is compared with the preset qualified index under the corresponding test pressure of the flow method to determine whether it meets the requirements.

[0025] If the qualified index is not reached, the flow method is used for further verification and judgment.

[0026] By adopting the above technical solution, the present application first calculates the air leakage volume under the test pressure of the flow method according to the aperture size of each leakage point; then accumulates the air leakage volumes of all leakage points to obtain an estimated total air leakage volume; compares this estimated value with a preset qualified index to preliminarily determine whether the requirements are met; for unqualified cases, the flow method is used for further verification and judgment, which can quickly obtain a preliminary qualified evaluation result, and the flow method can also be used for verification in case of unqualified cases, thus improving the detection efficiency and ensuring the reliability of the result.

[0027] Optionally, the first formula is:

[0028] Wherein, D is the size of the leakage aperture, P is the measured sound pressure level, P 0 is the reference sound pressure level, which takes the measured sound pressure level at a distance of 1 m from the reference hole with a distance of 1 mm from the aperture, and R represents the distance between the imaging device and the leakage point.

[0029] By adopting the above technical solution, since it is necessary to accurately estimate the size of the leakage aperture according to the ultrasonic signal, the present application uses the difference between the measured sound pressure level and the reference sound pressure level value, and combines the distance between the imaging device and the leakage point to establish a formula model for estimating the size of the leakage aperture, which can well reflect the typical sound pressure levels corresponding to different aperture sizes, thereby improving the estimation accuracy.

[0030] Optionally, the second formula is:

[0031] Wherein, q is the air leakage volume, Δp is the preset static pressure difference, ρ is the air density under standard conditions, and π is the pi.

[0032] By adopting the above technical solution, the present application uses the basic principle of fluid flow to establish a formula model that can calculate the air leakage volume by substituting parameters such as the aperture size and pressure difference, and can accurately calculate the air leakage volume of each leakage point under the specified pressure difference, providing data support for subsequent judgment of whether the airtight performance is qualified.

[0033] Optionally, after determining whether the requirements are met, the method further includes:

[0034] If the requirements are not met, a troubleshooting operation is performed, and the troubleshooting operation includes checking the installation status of the protection equipment and inspecting the quality status of the seals of the protection equipment;

[0035] If it is still unqualified after troubleshooting, tests on the compression reaction force, compression permanent deformation and aging coefficient of the seal are carried out to determine the root cause of the problem.

[0036] By adopting the above technical solutions, since in some cases, even with the above detection methods, the airtightness of the protective equipment may still be unqualified. When the detection result indicates that the airtightness of the protective equipment is unqualified, this application first checks whether there are problems with the overall installation status of the equipment, and at the same time inspects and tests the quality status of the seals to rule out leakage caused by installation or quality problems. If after the above investigations, the airtightness is still unqualified, then further compression reaction force tests, compression permanent deformation tests, aging coefficient tests, etc. need to be carried out on the seals themselves, so as to comprehensively evaluate the performance of the seals, find out the root cause of the unqualified airtightness, and thus comprehensively and accurately determine the reason for the unqualified airtightness, providing a clear basis for subsequent rectification measures.

[0037] In a second aspect, this application provides an airtightness detection system for protective equipment, including:

[0038] An ultrasonic transmitting device for transmitting ultrasonic waves inside the protective equipment to be detected;

[0039] An ultrasonic receiving device, including an ultrasonic imager, for capturing and recording ultrasonic signals from air leakage points;

[0040] A control system for controlling ultrasonic transmission and reception;

[0041] A data analysis unit for performing the following steps:

[0042] Determine the number and location of leakage points based on the ultrasonic signals;

[0043] For each detected punctiform leakage point, estimate the leakage aperture size according to the sound pressure level of the ultrasonic signal and the distance between the imaging device and the leakage point through a first formula;

[0044] Calculate the air leakage volume under the corresponding test pressure of the flow method according to the estimated leakage aperture size through a second formula, and compare it with a preset qualified index to determine whether it meets the requirements.

[0045] Optionally, it further includes:

[0046] A user interface device for allowing an operator to set detection parameters and view results.

[0047] In summary, this application includes at least one of the following beneficial technical effects:

[0048] 1. The present application provides a method for detecting the airtightness of a protective device, creating a non-pressure-difference environment inside and outside the protective device to be detected, setting an ultrasonic transmitting device inside and a receiving device outside; using the transmitting device to emit ultrasonic waves, and using the receiving device to capture and record ultrasonic signals from leakage points through ultrasonic imaging technology to determine the number and location of leakage points; for each detected punctiform leakage point, according to the sound pressure level of the ultrasonic signal and the distance between the imaging device and the leakage point, estimate the leakage aperture size through the first formula, and then calculate the air leakage volume under the flow method test pressure through the second formula based on the estimated leakage aperture size, and compare it with the preset qualified index to determine whether it meets the requirements. Compared with the traditional flow method, the detection efficiency is higher, the location of the leakage point can be accurately determined, and the operation is simpler, thus helping to improve the reliability and efficiency of the airtightness detection of the protective device;

[0049] 2. Due to the problem that a large leakage aperture will cause a large amount of air leakage, affecting the detection accuracy, the present application first determines obvious large-aperture leakage points according to the leakage aperture size and the shape of the leakage point; then temporarily plugs these obvious leakage points, and repeats the ultrasonic detection until there are no obvious leakage points. By plugging the large-aperture leakage points first, the air leakage volume can be effectively reduced, and the detection accuracy of subsequent small-aperture leakage points can be improved; at the same time, the operation is simple and will not affect the overall detection process, so the reliability and efficiency of the airtightness detection can be further improved;

[0050] 3. The present application first uses the internal ultrasonic transmitting device to emit ultrasonic waves, and uses the external receiving device to capture and record ultrasonic signals from leakage points through ultrasonic imaging technology, and generates a sound level spectrum according to these signals; then based on the obtained sound level spectrum, calculates the distribution image of the sound in space, and superimposes this sound distribution image on the image of the actual detected scene to obtain a superimposed composite image; finally, accurately identifies the specific position coordinates of each leakage point from this superimposed image and records them, which can intuitively and accurately display the position distribution of all leakage points, greatly improving the reliability and accuracy of leakage point identification. Description of the Drawings

[0051] Figure 1 is a schematic flow chart of a method for detecting the airtightness of a protective device according to an embodiment of the present application;

[0052] Figure 2 is a schematic diagram of the transmission and reception of ultrasonic waves in a method for detecting the airtightness of a protective device according to an embodiment of the present application;

[0053] Figure 3 is a schematic flow chart of a method for detecting the airtightness of a protective device according to an embodiment of the present application for processing obvious leakage points;

[0054] Figure 4It is a schematic flowchart of step S120 in a method for detecting the airtightness of a protective device according to an embodiment of the present application;

[0055] Figure 5 It is a schematic flowchart of step S140 in a method for detecting the airtightness of a protective device according to an embodiment of the present application;

[0056] Figure 6 It is a schematic flowchart of determining the root cause of problems in a method for detecting the airtightness of a protective device according to an embodiment of the present application;

[0057] Figure 7 It is a schematic structural diagram of a system for detecting the airtightness of a protective device according to an embodiment of the present application. Detailed implementation manners

[0058] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments and are not intended to limit the present application. As used in the specification and appended claims of the present application, the singular forms "a", "an", "the", "above-mentioned", "said", and "this" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It should also be understood that the term " / and / " used in the present application refers to any and all possible combinations including one or more of the listed items.

[0059] Hereinafter, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as implying or suggesting relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include one or more of such features. In the description of the embodiments of the present application, unless otherwise stated, the meaning of "a plurality" is two or more.

[0060] The following further describes the embodiments of the present application in detail with reference to the accompanying drawings of the specification.

[0061] In a first aspect, the present application provides a method for detecting the airtightness of a protective device, with reference to Figure 1 , including the following steps: S110. Set an ultrasonic transmitting device inside the protective device to be detected, configure an ultrasonic receiving device outside, and create a non-pressure-difference environment inside and outside the protective device.

[0062] In this embodiment, the protective device to be tested is mainly a reinforced concrete airtight door. Among them, the arrangement positions of the ultrasonic transmitting device and the receiving device need to be determined according to the specific structure of the protective device to be tested. The key is to be able to cover the area to be tested and obtain effective signals. Alternatively, test points can be preset, and the ultrasonic transmitting device and the receiving device can be moved by the staff for measurement. In addition, by adjusting the air pressure inside and outside the protective device, it is ensured that a non-pressure-difference environment is formed during the detection process.

[0063] Specifically, the ultrasonic emission device can be portable and easy to install and move. It should emit ultrasonic waves of a specific frequency, such as ultrasonic waves of 40 kHz, because this frequency can effectively penetrate the materials of most protective equipment and is not affected by environmental noise. The ultrasonic receiving device should have high sensitivity and be able to capture weak ultrasonic signals. In order to create a pressure - free - difference environment, it can be achieved by using a pressure - regulating device inside the protective equipment. For example, an air pump and a pressure regulating valve are used to adjust the internal pressure to be equal to the external environmental pressure. In actual operation, it is also necessary to ensure the stable and reliable power supply of the ultrasonic emission and receiving devices to avoid signal interruption.

[0064] S120. Use the ultrasonic emission device to emit ultrasonic waves inside the protective equipment, and use the ultrasonic receiving device to capture and record the ultrasonic signals from the air leakage points through ultrasonic imaging technology to determine the number and location of the leakage points.

[0065] In this embodiment, referring to Figure 2 , the ultrasonic signals emitted by the ultrasonic emission device will produce specific acoustic characteristics at the air leakage points, and these characteristics can be captured by the ultrasonic receiving device. Ultrasonic imaging technology can convert these signals into images, thus helping the detection personnel to determine the number and specific location of the leakage points. To improve the detection efficiency, multiple ultrasonic receiving devices can be used simultaneously to capture the ultrasonic signals emitted from the leakage points from different angles.

[0066] Specifically, the ultrasonic emission device should be set to continuously emit ultrasonic waves of a constant frequency to ensure a stable signal source. The ultrasonic receiving device is equipped with advanced imaging technology, such as an ultrasonic imager, which can capture and record the ultrasonic signals from the leakage points and convert these signals into images that are easy to interpret through software. By analyzing these images, the number and location of the leakage points can be quickly determined. To ensure the accuracy of the images, the ultrasonic receiving devices can be pre - calibrated and ensure that they can capture the signals emitted from the leakage points at different distances. In addition, the synchronization between the ultrasonic emission and receiving devices should also be ensured to reduce signal interference.

[0067] S130. For each detected point - like leakage point, estimate the leakage aperture size according to the sound pressure level of the ultrasonic signal and the distance between the imaging device and the leakage point through the first formula.

[0068] In this embodiment, for each detected point - like leakage point, it is necessary to estimate the size of the leakage aperture through the sound pressure level of the ultrasonic signal and the distance between the imaging device and the leakage point.

[0069] Specifically, by measuring the sound pressure level of the ultrasonic signal and determining the distance between the ultrasonic receiving device and the leakage point, the first formula can be used to estimate the size of the leakage aperture. This formula is based on the attenuation characteristics of ultrasonic waves, and the first formula is:

[0070] where D is the size of the leakage aperture, P is the measured value of the sound pressure level, and P 0 is the reference value of the sound pressure level, which is the measured value of the sound pressure level at a distance of 1 m from the reference hole with a diameter of 1 mm from the aperture, and R represents the distance between the imaging device and the leakage point.

[0071] S140. According to the estimated size of the leakage aperture, calculate the air leakage volume at the corresponding test pressure by the flow method, and compare it with the preset qualified index to determine whether it meets the requirements.

[0072] In this embodiment, based on the size of the leakage aperture estimated in the previous step, the air leakage volume at a specific test pressure can be calculated by the second formula. Then, by comparing the air leakage volume with the preset qualified index, it can be determined whether the airtight performance of the protective equipment meets the standard.

[0073] Specifically, the second formula is a preset mathematical expression that can relate the size of the leakage aperture, the test pressure, and other relevant parameters to estimate the air leakage volume under given pressure conditions.

[0074] In one embodiment, referring to Figure 3 , step S130, after estimating the size of the leakage aperture by the first formula, the method further includes the following steps:

[0075] S310. Determine the obvious leakage points according to the estimated size of the leakage aperture and the shape of the leakage point.

[0076] In this embodiment, after estimating the size of the leakage aperture, it is necessary to further analyze the shape and size of the leakage point to determine which leakage points are obvious leakage points.

[0077] Specifically, by analyzing the image of the leakage point captured by the ultrasonic imaging technology, the shape of the leakage point can be observed. For example, if the leakage point appears as a dot and its estimated aperture size exceeds a certain threshold (such as 1 mm), it is considered an obvious leakage point. On the other hand, if the leakage point appears as a line, even if its aperture size is small, it may be regarded as an obvious leakage point because there may be multiple continuous leakage points. In the process of determining the obvious leakage points, the position of the leakage point also needs to be considered. For example, if the leakage point is located at a key part (such as a door seam or a locking shaft hole), even if the aperture is small, it needs special attention. In addition, historical data can also be referred to understand the common leakage point positions of the same type of protective equipment, so as to more efficiently locate the obvious leakage points.

[0078] S320. Temporarily plug the detected obvious leakage points and perform ultrasonic detection again until there are no obvious leakage points.

[0079] In this embodiment, once the obvious leakage points are determined, the next step is to temporarily plug them and then perform ultrasonic detection again to verify the effect of the plugging. This process may need to be repeated multiple times until no obvious leakage points are detected.

[0080] Specifically, use temporary plugging materials (such as sealing tapes or other types of sealing materials) to plug the obvious leakage points. After plugging, start the ultrasonic detection again to observe whether there are still leakage points detected. If there are still obvious leakage points, the cycle of plugging and detection needs to continue until all obvious leakage points are properly handled and the ultrasonic detection no longer shows obvious leakage points. When plugging, attention also needs to be paid to the selection of materials to ensure that the used plugging materials will not damage the protective equipment and can be cured in a short time to reduce the downtime.

[0081] In one embodiment, referring to Figure 4 , in step S120, use an ultrasonic transmitting device to emit ultrasonic waves inside the protective equipment, and use an ultrasonic receiving device to capture and record the ultrasonic signals from the air leakage points through ultrasonic imaging technology to determine the number and location of the leakage points. The specific steps are as follows:

[0082] S121. Use an ultrasonic transmitting device to emit ultrasonic waves inside the protective equipment, and use an ultrasonic receiving device to capture and record the ultrasonic signals from the air leakage points through ultrasonic imaging technology, and generate a sound level spectrum according to the ultrasonic signals.

[0083] In this embodiment, inside the closed protective equipment, use an ultrasonic transmitting device to emit ultrasonic waves in all directions. These ultrasonic waves will propagate in the space inside the protective equipment. If they encounter air leakage points, specific ultrasonic signals will be generated. After the ultrasonic receiving device captures these signals, it will generate a sound level spectrum through ultrasonic imaging technology. This spectrum reflects the intensity distribution of ultrasonic signals at different frequencies.

[0084] Specifically, for example, an ultrasonic imager equipped with a high-sensitivity microphone array can be used, such as the Fluke ii910 acoustic imager, which can capture ultrasonic signals of different frequencies and generate a sound level spectrum based on these signals. When ultrasonic waves encounter a leakage point, due to the flow of gas, a vortex effect will be generated, thus exciting ultrasonic waves, which will be captured by the ultrasonic receiving device. By analyzing these signals, it is possible to determine whether there is a leakage point and the approximate location of the leakage point. In practical applications, it is also necessary to ensure the synchronization and stability of the transmitting and receiving devices to improve the detection accuracy.

[0085] S122. Based on the sound level spectrum, calculate the sound distribution image and superimpose the sound distribution image on the actual scene image to obtain a superimposed image.

[0086] In this embodiment, based on the sound distribution image generated from the sound level spectrum, through algorithm calculation, these images are combined with the image of the actual scene to form a superimposed image. In this way, it is possible to visually see which positions have leakage points.

[0087] Specifically, for example, using the Fluke ii910 acoustic imager, it can automatically superimpose the sound distribution image on the actual scene image captured by the camera to form a superimposed image. In this image, different-colored hot spots will be displayed around the leakage point. The brighter the color of these hot spots, the stronger the ultrasonic signal at that position, and the more obvious the leakage point. This method enables technicians to quickly locate the specific position of the leakage point, facilitating subsequent processing. To improve the image quality, it is also necessary to regularly calibrate the ultrasonic imager to ensure its stable performance.

[0088] S123. Identify the position of the leakage point from the superimposed image, and record the number and position coordinates of the leakage point.

[0089] In this embodiment, by analyzing the superimposed image, the position of the leakage point can be clearly identified. Mark the position of the leakage point in the image, and record the number of leakage points and their coordinate positions in the protective equipment.

[0090] Specifically, for example, in the superimposed image, the leakage point usually appears as a brightly colored hot spot. Technicians can manually mark it or use software to automatically identify the position of these hot spots and record their coordinate information. These coordinate information are crucial for subsequent repair work because they can help the staff quickly find the leakage point for plugging or replacing the seal. In addition, recording the number of leakage points is also necessary, which helps to evaluate the overall airtight performance of the protective equipment and determine whether further inspections or repair measures are needed.

[0091] In one embodiment, referring to Figure 5, in step S140, according to the estimated leakage aperture size, calculate the air leakage amount at the corresponding test pressure in the flow method through the second formula, and compare it with the preset qualified index to determine whether it meets the requirements. Specifically, it includes the following steps:

[0092] S141. According to the estimated leakage aperture size of each punctiform leakage aperture, calculate the air leakage amount at the corresponding test pressure in the flow method through the second formula.

[0093] In this embodiment, after detecting the punctiform leakage points, according to the aperture size of each leakage point, use the second formula to calculate the corresponding air leakage amount, taking into account factors such as leakage aperture, test pressure, and air density, so as to estimate the accurate air leakage amount.

[0094] Specifically, the second formula is:

[0095] where q is the air leakage amount, Δp is the preset static pressure difference, ρ is the air density under standard conditions, and π is the pi.

[0096] S142. According to the air leakage amount of each punctiform leakage aperture, obtain the cumulative air leakage amount estimation value of all punctiform leakage apertures.

[0097] In this embodiment, add up the air leakage amounts corresponding to all punctiform leakage apertures to obtain the cumulative air leakage amount estimation value of the entire protective equipment, so as to comprehensively evaluate the overall airtight performance of the protective equipment.

[0098] Specifically, for example, if three punctiform leakage apertures are found during the detection, and their air leakage amounts are 0.05 m 3 / h, 0.07 m 3 / h, and 0.03 m 3 / h respectively, then the cumulative air leakage amount estimation value of these three leakage points is 0.05 + 0.07 + 0.03 = 0.15 m 3 / h. This cumulative air leakage amount estimation value will be used for the next comparison with the qualified index.

[0099] S143. Compare the cumulative air leakage amount estimation value with the preset qualified index at the corresponding test pressure in the flow method to determine whether it meets the requirements.

[0100] In this embodiment, compare the cumulative air leakage amount estimation value obtained in the previous step with the preset qualified index to determine whether the airtight performance of the protective equipment meets the qualified standard.

[0101] Specifically, for example, if the qualified index stipulates that at a test pressure of 50 Pa, the maximum allowable air leakage amount of the protective equipment is 0.2 m 3 / h, and the estimated cumulative air leakage volume we calculated is 0.15m 3 / h, then it can be considered that the airtight performance of the protective equipment meets the requirements. Conversely, if the estimated cumulative air leakage volume exceeds the maximum allowable value specified by the qualified index, it indicates that there is a problem with the airtight performance of the protective equipment.

[0102] S144. If the qualified index is not met, the flow method is used for further verification and judgment.

[0103] In this embodiment, if the estimated cumulative air leakage volume fails to meet the requirements of the qualified index, the traditional flow method needs to be used for further verification and confirmation.

[0104] Specifically, for example, if the estimated cumulative air leakage volume is 0.25m 3 / h, exceeding 0.2m of the qualified index 3 / h, then the flow method needs to be used for actual measurement. This means that a closed space needs to be set up on the protective equipment, pressurized in this space, and then the air leakage volume passing through the leakage point within a certain period of time is measured. If the actual measurement result of the flow method is still higher than the qualified index, the protective equipment needs to be repaired or the seal is replaced to improve its airtight performance.

[0105] In one embodiment, referring to Figure 6 , step S140, after determining whether it meets the requirements, the method further includes:

[0106] S610. If it does not meet the requirements, a troubleshooting operation is performed. The troubleshooting operation includes checking the installation status of the protective equipment and inspecting the quality status of the seals of the protective equipment.

[0107] In this embodiment, when it is detected that the airtight performance of the protective equipment does not meet the requirements, a series of troubleshooting operations need to be performed to determine the problem. These troubleshooting operations mainly include checking the installation status of the protective equipment and inspecting the quality status of the seals of the protective equipment.

[0108] Specifically, for example, for the inspection of the installation status of the protective equipment, it can include checking whether the connection between the door frame and the wall is firm, whether the fit between the door leaf and the door frame is tight, and whether components such as door locks are intact. In addition, it is also necessary to check whether the seals are installed correctly and whether there is wear or damage. For the inspection of the quality status of the seals, visual inspection, touch inspection, etc. can be used to initially judge the state of the seals, and further use professional detection tools for more detailed inspection.

[0109] S620. If it is still unqualified after troubleshooting, tests on the compression reaction force, compression permanent deformation, and aging coefficient of the seals are performed to determine the root cause of the problem.

[0110] In this embodiment, if the problem cannot be solved after preliminary troubleshooting, more detailed tests need to be carried out on the seal to determine the root cause of the problem. These tests include compression reaction force, compression set, and aging coefficient tests.

[0111] Specifically, for example, for the compression reaction force test, a special test device such as a universal testing machine can be used to fix the seal specimen between the upper and lower test fixtures and apply a load at a certain speed, recording the instantaneous compression force at different compression amounts. This helps to evaluate the performance of the seal under pressure. For the compression set test, the seal can be compressed under conditions simulating the actual use environment and held for a period of time, and then the pressure is released to measure its recovery degree. This can evaluate whether the seal will affect its performance due to deformation after long-term use. As for the aging coefficient test, the seal is subjected to accelerated aging treatment under simulated high-temperature conditions, and then the changes in its physical properties are tested to evaluate the performance stability of the seal after long-term use. When conducting these tests, it is also necessary to ensure the consistency and repeatability of the test conditions to improve the credibility of the test results.

[0112] It should be understood that the magnitudes of the sequence numbers of the steps in the above embodiments do not mean the order of execution. The order of execution of each process should be determined by its function and internal logic, and should not constitute any limitation to the implementation process of the embodiments of the present application.

[0113] In a second aspect, the present application provides a tightness detection system for a protective device. The tightness detection system for the protective device of the present application will be described below in combination with the above-mentioned tightness detection method for the protective device.

[0114] Referring to Figure 7 , a tightness detection system for a protective device includes:

[0115] An ultrasonic transmitting device for transmitting ultrasonic waves inside the protective device to be detected;

[0116] An ultrasonic receiving device, including an ultrasonic imager, for capturing and recording ultrasonic signals from air leakage points;

[0117] A control system for controlling ultrasonic transmission and reception;

[0118] A data analysis unit for performing the following steps:

[0119] Determining the number and location of leakage points according to the ultrasonic signals;

[0120] For each detected point-like leakage point, estimating the leakage aperture size according to the sound pressure level of the ultrasonic signal and the distance between the imaging device and the leakage point through a first formula;

[0121] According to the estimated leakage aperture size, calculate the air leakage volume at the corresponding test pressure in the flow method through the second formula, and compare it with the preset qualified index to determine whether it meets the requirements.

[0122] Furthermore, it also includes:

[0123] A user interface device for an operator to set detection parameters and view results.

[0124] Furthermore, it also includes:

[0125] A communication module for realizing wireless or wired communication among the components of the detection system, supporting multiple communication protocols such as Wi-Fi, Bluetooth, and Ethernet; ensuring the security and stability of data transmission.

[0126] An air pressure regulating device for regulating the air pressure inside the protective equipment to ensure a non-pressure difference environment during the detection process. It includes an air pump and a pressure regulating valve, and can adjust the internal pressure to be equal to the external environmental pressure as needed.

[0127] A mobile platform for assisting the movement of the ultrasonic transmitting and receiving devices. It can be designed as a manual or automatic mobile platform according to needs, facilitating the flexible movement of the transmitting and receiving devices inside a large protective equipment.

[0128] A power management unit for supplying power to the entire detection system, supporting battery power supply and AC power supply, ensuring the portability and long-term operation ability of the detection system.

[0129] An alarm system for triggering an alarm when a leakage point is detected, which can remind the operator of the leakage point through means such as sound and light; supports threshold setting, and automatically triggers an alarm when the detected air leakage volume exceeds the preset threshold.

[0130] The above are all preferred embodiments of this application, and do not limit the protection scope of this application accordingly. Therefore, all equivalent changes made according to the structure, shape, and principle of this application should be covered within the protection scope of this application.

Claims

1. A method for detecting the tightness of protective equipment, characterized in that: The steps include: An ultrasonic transmitting device is arranged inside the protective equipment to be tested, and an ultrasonic receiving device is arranged outside, so that a pressure difference-free environment is formed inside and outside the protective equipment; An ultrasonic transmitter is used to transmit ultrasonic waves inside the protective equipment, and an ultrasonic receiver is used to capture and record ultrasonic signals from air leakage points through ultrasonic imaging technology, and a sound level spectrum is generated based on the ultrasonic signals; Based on the sound level spectrum, a sound distribution image is calculated and the sound distribution image is superimposed on the actual scene image to obtain a superimposed image; Identify the location of the leak points from the superimposed image and record the number and location coordinates of the leak points; For each detected point-shaped leak, the leak aperture size is estimated by the first formula according to the sound pressure level of the ultrasonic signal and the distance between the imaging device and the leak; Determine the obvious leakage point based on the estimated leakage aperture size and the shape of the leakage point; Temporarily block the obvious leak points detected and perform ultrasonic testing again until there are no obvious leak points; According to the estimated leakage aperture size of each point leakage aperture, the leakage volume under the corresponding test pressure of the flow method is calculated by the second formula; According to the leakage volume of each point leakage aperture, the estimated value of the cumulative leakage volume of all point leakage apertures is obtained; Compare the estimated value of the accumulated air leakage with the preset qualified index under the corresponding test pressure of the flow method to determine whether it meets the requirements; If the qualified indicators are not met, the flow method is used for further verification and judgment.

2. The method for detecting the tightness of protective equipment according to claim 1, characterized in that: The first formula is: Where D is the size of the leakage aperture, P is the measured value of the sound pressure level, P0 is the reference value of the sound pressure level, which is the measured value of the sound pressure level at a distance of 1m from a reference hole with an aperture of 1mm, and R represents the distance between the imaging device and the leakage point.

3. The method for detecting tightness of protective equipment according to claim 2, characterized in that: The second formula is: Among them, q is the leakage, Δp is the preset static pressure difference, ρ is the air density under standard conditions, and π is the pi.

4. The method for detecting the tightness of protective equipment according to claim 1, characterized in that: After determining whether the requirements are met, the method further includes: If it does not meet the requirements, a troubleshooting operation is performed, which includes checking the installation status of the protective equipment and performing a quality status inspection on the seals of the protective equipment; If it is still unqualified after elimination, the seal will be tested for compression reaction force, compression permanent deformation and aging coefficient to determine the root cause of the problem.

5. A sealing detection system for protective equipment, characterized in that: include: An ultrasonic emitting device, used for emitting ultrasonic waves inside the protective equipment to be detected; An ultrasonic receiving device, including an ultrasonic imager, for capturing and recording ultrasonic signals from an air leakage point; A control system for controlling ultrasonic emission and reception; The data analysis unit is used to perform the following steps: Generate a sound level spectrum according to the ultrasonic signal; Based on the sound level spectrum, a sound distribution image is calculated and the sound distribution image is superimposed on the actual scene image to obtain a superimposed image; Identify the location of the leak points from the superimposed image and record the number and location coordinates of the leak points; For each detected point-shaped leak, the leak aperture size is estimated by the first formula according to the sound pressure level of the ultrasonic signal and the distance between the imaging device and the leak; Determine the obvious leakage point based on the estimated leakage aperture size and the shape of the leakage point; Temporarily block the obvious leak points detected and perform ultrasonic testing again until there are no obvious leak points; According to the estimated leakage aperture size of each point leakage aperture, the leakage volume under the corresponding test pressure of the flow method is calculated by the second formula; According to the leakage volume of each point leakage aperture, the estimated value of the cumulative leakage volume of all point leakage apertures is obtained; Compare the estimated value of the accumulated air leakage with the preset qualified index under the corresponding test pressure of the flow method to determine whether it meets the requirements; If the qualified indicators are not met, the flow method is used for further verification and judgment.

6. The airtightness detection system for protective equipment according to claim 5, characterized in that: Also includes: User interface device, used for operators to set test parameters and view results.

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