Iron box sealing performance detection system

Abstract

The invention discloses an iron box sealing performance detection system, relates to the technical field of sealing detection, and adopts a differential pressure principle to realize waterless air tightness detection of a bullet packaging iron box. Through reasonable model selection of detection instruments, communication between the detector and the PLC can be realized, so that automatic multi-station detection is realized, the labor cost is reduced, and the production efficiency is improved. The system can adjust various parameters such as test pressure intensity, test time and test threshold values according to actual production requirements to realize detection of various products; test results, data and the like can be transmitted to the display screen, production conditions can be observed conveniently, the detection system can be operated through the display screen, and the system is easy to learn and use while safety is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of sealing testing technology, and in particular to a sealing performance testing system for iron boxes based on the principle of pressure difference. Background Technology

[0002] Sealing inspection is crucial for ensuring product quality, improving product reliability, and protecting personal safety. It provides a quantitative assessment of a product's sealing performance by measuring indicators such as leakage or pressure changes. This allows for the determination of whether the product's sealing meets requirements, enabling early detection of sealing problems and facilitating repair or replacement, thus reducing the production of defective products. The importance of sealing inspection for ammunition packaging is self-evident. Its application in ammunition packaging primarily ensures the packaging's airtightness, preventing moisture, dust, and other contaminants from entering the packaging and affecting the ammunition's performance.

[0003] Currently, in the ammunition production process, the sealing of ammunition packaging boxes is mostly tested using the positive pressure immersion leak detection method. This involves operators using a hose to inject a certain amount of gas into the box through a pre-drilled vent at the top, then immersing the box in water. The formation of bubbles is observed to determine the seal. If bubbles appear in a certain area of ​​the box, it indicates a poor seal. The box is then removed, dried, and the leaking point is welded to the vent. If there are no leaks, the vent is still welded shut. This method is low-cost and easily identifies leaks in the box.

[0004] Helium mass spectrometry leak detection is a sealing detection method that utilizes the low permeability and high sensitivity of helium gas, namely its small molecular size, ease of passing through small pores, and reverse diffusion. The relatively high abundance of helium allows helium mass spectrometers to detect minute amounts of helium. A leak indicator gas with a helium concentration above atmospheric pressure is introduced into the chamber being tested. This method offers high measurement accuracy and can precisely pinpoint the leak location.

[0005] However, the positive pressure immersion leak detection method is highly dependent on manual labor, requiring three operators to ensure normal production efficiency; the operation is complex and difficult to automate, takes a long time, and has low production efficiency; a single full-load iron box weighs more than 10kg, resulting in high labor intensity for personnel during mass production.

[0006] Meanwhile, the helium mass spectrometry leak detection method requires solving the problem of helium storage, and the equipment is large, costly, and time-consuming, making it unsuitable for rapid on-site testing of bullet packaging. Summary of the Invention

[0007] In view of the above problems, the present invention provides a steel box sealing performance testing system for overcoming or at least partially solving the above problems.

[0008] This invention provides the following solution: A system for detecting the sealing performance of an iron box, comprising: The iron box transfer unit includes a detection station base and an iron box transfer line, and the iron box transfer line is provided with a detection station inlet and outlet. A differential pressure sealing detection unit includes a gas source, a differential pressure sensor, a test end assembly, and a reference end assembly. The test end assembly includes a test gas path and a test sealing cover. The reference end assembly includes a reference gas path and a sealed reference cavity. The test gas path and the reference gas path are arranged in parallel and are both connected to the gas source. The differential pressure sensor is connected to both the test gas path and the reference gas path. The test sealing cover is sealed at the top and sides and open at the bottom; the test sealing cover is set above the test station base by a lifting mechanism. The lifting mechanism is used to drive the test sealing cover to descend after determining that there is an iron box to be tested on the test station base, so that the test sealing cover covers the iron box to be tested and the test sealing cover and the test station base together form a sealed test chamber. The gas source is used to simultaneously evacuate the sealed reference chamber and the sealed test chamber after the sealed test chamber is formed, so that after the pressure inside the sealed reference chamber and the sealed test chamber stabilizes, the test pressure difference of the differential pressure sensor is read, and the test box to be tested is determined to be poorly sealed after the test pressure difference exceeds the pressure difference threshold.

[0009] Preferably, the test end assembly further includes a first pressure dividing tank, and the reference end assembly further includes a second pressure dividing tank; the first pressure dividing tank is connected to the test gas circuit through a first pressure dividing valve, and the second pressure dividing tank is connected to the reference gas circuit through a second pressure dividing valve.

[0010] Preferably, both the first pressure dividing valve and the second pressure dividing valve are normally closed pressure dividing valves.

[0011] Preferably, a first pressure regulating valve is provided on the test gas line, and a second pressure regulating valve is provided on the reference gas line.

[0012] Preferably, both the first pressure regulating valve and the second pressure regulating valve are normally open pressure regulating valves.

[0013] Preferably, the gas source is connected to an inflation valve, and both the test gas path and the reference gas path are connected to the inflation valve.

[0014] Preferably, the inflation valve is connected to a test pressure sensor.

[0015] Preferably, the inflation valve is connected to an exhaust valve.

[0016] Preferably, the iron box transfer unit further includes a feeding mechanism, which is used to drive the iron box to be tested to switch positions between the test station base and the iron box transfer line via the test station entrance / exit.

[0017] Preferably, the feeding mechanism includes a suction cup and a push-pull cylinder.

[0018] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects: This application provides a metal box sealing test system that uses the differential pressure principle to test the airtightness of ammunition packaging metal boxes without water. By appropriately selecting the testing instruments, communication between the testing instruments and a PLC can be achieved, enabling automated multi-station testing, reducing labor costs, and improving production efficiency. The system can adjust various parameters such as test pressure, test time, and test threshold according to actual production needs, enabling the testing of various products. Test results and data can be transmitted to a display screen for easy observation of production status. The system can also be operated via the display screen, ensuring safety while being easy to learn and use.

[0019] Of course, any product implementing this invention does not necessarily need to achieve all of the advantages described above at the same time. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly described below. Obviously, the drawings described below are merely some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without any creative effort.

[0021] Figure 1 This is a schematic diagram of the gas path of the differential pressure sealing detection unit provided in this embodiment of the invention; Figure 2 This is a process flow diagram of the sealing performance testing production line provided in an embodiment of the present invention.

[0022] In the diagram: 1. Gas source; 2. Differential pressure sensor; 31. Test gas path; 32. Test sealing cover; 33. First pressure divider tank; 34. First pressure divider valve; 35. First pressure stabilizing valve; 41. Reference gas path; 42. Sealed reference chamber; 43. Second pressure divider tank; 44. Second pressure divider valve; 45. Second pressure stabilizing valve; 5. Inflation valve; 6. Test pressure sensor; 7. Exhaust valve. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention are within the scope of protection of the present invention.

[0024] See Figure 1 This invention provides a system for detecting the sealing performance of an iron box, such as... Figure 1 As shown, the system may include: The iron box transfer unit includes an inspection station base and an iron box transfer line, wherein the iron box transfer line is provided with an inspection station inlet and outlet. A differential pressure sealing detection unit includes a gas source 1, a differential pressure sensor 2, a test end assembly, and a reference end assembly. The test end assembly includes a test gas path 31 and a test sealing cover 32. The reference end assembly includes a reference gas path 41 and a sealed reference cavity 42. The test gas path 31 and the reference gas path 41 are arranged in parallel and are both connected to the gas source 1. The differential pressure sensor 2 is connected to both the test gas path 31 and the reference gas path 41. The test sealing cover 32 is sealed at the top and sides and open at the bottom; the test sealing cover 32 is set above the test station base by a lifting mechanism. The lifting mechanism is used to drive the test sealing cover 32 to descend after determining that there is an iron box to be tested on the test station base, so that the test sealing cover 32 covers the iron box to be tested and the test sealing cover 32 and the test station base together form a sealed test chamber. The gas source 1 is used to simultaneously perform a vacuuming operation on the sealed reference cavity 42 and the sealed test cavity after the sealed test cavity is formed, so that after the pressure inside the sealed reference cavity 42 and the sealed test cavity stabilizes, the test pressure difference of the differential pressure sensor 2 is read, and the test box to be tested is determined to be poorly sealed after the test pressure difference exceeds the pressure difference threshold.

[0025] The iron box sealing performance testing system provided in this application utilizes a differential pressure sealing performance tester that operates based on the principle of pressure difference. During operation, the test piece is first placed in a sealed chamber, and both the test chamber and the reference chamber are simultaneously inflated or evacuated to reach the test pressure. Then, the air passage between the chamber and the outside is shut off, and the pressure change within the test chamber is monitored in real time by a built-in sensor. If the test piece leaks, the pressure within the test chamber will change, creating a pressure difference between the test chamber and the reference chamber. This pressure difference is captured by the sensor and converted into a specific leakage amount through data processing.

[0026] To address the problem that a severely poor seal in the iron box leads to rapid gas escape and no significant change in pressure difference during sensor readings, making it impossible to determine if the seal is faulty, this application embodiment provides that the test end assembly further includes a first pressure dividing tank 33, and the reference end assembly further includes a second pressure dividing tank 43; the first pressure dividing tank 33 is connected to the test gas path 31 via a first pressure dividing valve 34, and the second pressure dividing tank 43 is connected to the reference gas path 41 via a second pressure dividing valve 44.

[0027] Furthermore, both the first pressure dividing valve 34 and the second pressure dividing valve 44 are normally closed pressure dividing valves.

[0028] To improve the stability of the gas source 1, this embodiment of the application provides a first pressure regulating valve 35 on the test gas path 31 and a second pressure regulating valve 45 on the reference gas path 41. Both the first pressure regulating valve 35 and the second pressure regulating valve 45 are normally open pressure regulating valves. The gas source 1 is connected to an inflation valve 5, and both the test gas path 31 and the reference gas path 41 are connected to the inflation valve 5. The inflation valve 5 is connected to a test pressure sensor 6. The inflation valve 5 is also connected to an exhaust valve 7. By using the pressure regulating valves, the influence of pressure fluctuations in the gas source 1 on the detection results is eliminated, thereby improving the accuracy and stability of the detection.

[0029] It is understandable that, in practical applications, the iron box transfer unit can take various forms. For example, in one implementation, this embodiment may provide that the iron box transfer unit further includes a feeding mechanism. The iron box transfer line is used to transfer the iron box to be tested, and the feeding mechanism is used to drive the iron box to be tested through the inlet and outlet of the testing station, switching its position between the testing station base and the iron box transfer line. Further, the feeding mechanism includes a suction cup and a push-pull cylinder.

[0030] The following section provides a detailed description of the iron box sealing detection system provided in this application embodiment, using an iron box transmission line as the transmission unit as an example.

[0031] In the differential pressure sealing detection unit, the first pressure regulating valve 35 and the second pressure regulating valve 45 are normally open, and the first pressure dividing valve 34 and the second pressure dividing valve 44 are normally closed. The first pressure dividing tank 33 and the second pressure dividing tank 43 have the same specifications. The test end is a sealed gas tank, the volume of which is approximately equal to the test chamber volume minus the iron box volume. The detection principle is as follows: (1) After the test chamber is sealed, the inflation valve 5 is opened and the gas source 1 (vacuum generator) is pumped out to create a negative pressure in the entire test circuit; (2) The inflation valve 5, the first pressure regulating valve 35 and the second pressure regulating valve 45 are closed, and the pressure is stabilized for a certain period of time so that the pressure at the test end and the reference end tends to be stable; (3) The differential pressure sensor starts reading the pressure difference between the sealed test chamber and the sealed reference chamber 42. If the iron box being tested is not properly sealed, the gas inside the differential pressure sensor will escape during the reading process, causing the measured pressure difference to increase. (4) The pressure regulating valve remains closed and the pressure dividing valve is opened. The gas in the pressure dividing tank is diverted to the sealed test chamber and the sealed reference chamber 42. The differential pressure sensor reads the pressure difference again. In step (3), if the iron box is severely unsealed, the gas inside it will escape rapidly, so that the pressure difference does not change significantly during the sensor reading process. At this time, it is impossible to determine that its sealing is unqualified. In this step, after the gas in the pressure dividing tube is diverted, the difference in the volume of the test end and the reference end and the first pressure dividing tank 33 and the second pressure dividing tank 43 connected to them increases. At this time, the gas in the cavity comes from the corresponding pressure dividing tank, that is, the total amount of gas is the same. From PV=nRT, the pressure difference between the two ends increases. (5) The differential pressure sealing detection unit determines whether the iron box is qualified based on the pressure difference measured by the differential pressure sensor in steps (3) and (4). If the pressure difference in both steps is within the set value range, it is qualified; otherwise, it is unqualified. The differential pressure sealing detection unit outputs the test result, the exhaust valve 7 is opened, the pressure in the detection circuit is restored to atmospheric pressure, and each valve is restored to the state before the test.

[0032] The process flow of the sealing test production line is as follows: Figure 2 As shown.

[0033] The specific process flow is as follows: Iron box arrival: The iron box is delivered to the outside of the inspection station by the iron box conveyor line; the control system (PLC) detects the arrival of the iron box and starts the feeding mechanism such as suction cup and push-pull cylinder to send the iron box to the inspection station base of the sealing inspection station.

[0034] Sealing test of the iron box: After the iron box is sent to the sealing test station, the cover is lowered to form a sealed test chamber with the base of the test station; the control system sends a test start signal to the sealing tester, and the sealing tester begins to test the iron box under test. After the test is completed, the tester transmits the measured data, qualification information and other information back to the control system, and the feeding mechanism sends the iron box back to the transmission line.

[0035] Iron box release / rejection: After the iron box is sent back to the conveyor line by the feeding mechanism, the conveyor line will send the inspected iron box to the rejection station. The control system will reject or release the iron box according to its qualification.

[0036] The iron box sealing test system provided in this application can accurately detect leaks of both small and large magnitudes, offering a new process for iron box sealing test. To achieve efficient and reliable automated testing, this method proposes a process flow suitable for differential pressure testing. The selection of testing instruments capable of quickly establishing communication with a PLC makes data transmission and storage more efficient; the convenient and diverse parameter settings enhance the compatibility of the testing system.

[0037] Understandably, this method has room for optimization: for situations where the test piece is not placed correctly, resulting in gaps in the sealing cavity, a self-test function could be used, and the system could shut down abnormal gas paths while continuing testing for normal gas paths. This method optimizes the testing process under abnormal conditions, which has a positive effect on improving testing efficiency and is worth learning from.

[0038] Another method involves filling the test chamber with a certain amount of gas and allowing it to stand for a period of time. If the pressure change in the test chamber is significant, a minor leak can be identified. Alternatively, the test chamber can be connected to an auxiliary sealed chamber. If the pressure change in the auxiliary sealed chamber is significant, a major leak is present in the tested component. If the pressure changes in both the test chamber and the auxiliary sealed chamber are small, the tested component can be considered to have good sealing performance. This method uses a simpler test circuit, which can further reduce testing costs and optimize the spatial layout of the testing system.

[0039] In summary, the iron box sealing test system provided in this application enables the testing of the airtightness of ammunition packaging iron boxes without water. Through the appropriate selection of testing instruments, communication between the testing instrument and the PLC can be achieved, thereby realizing automated multi-station testing, reducing labor costs, and improving production efficiency. This method allows for the adjustment of various parameters such as test pressure, test time, and test threshold according to actual production needs, enabling the testing of various products. Test results and data can be transmitted to a display screen for easy observation of production conditions. The testing system can also be operated through the display screen, ensuring safety while being easy to learn and use.

[0040] Meanwhile, the production line using this system has been verified in actual use to reduce the number of people required for the iron box sealing inspection process from the original 3 people to 1 person (the safety officer who is necessary to ensure on-site safety); the method effectively improves production efficiency, with an average of 1.5 iron boxes being inspected per minute, and the inspection results are accurate with no misjudgments.

[0041] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0042] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0043] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to mutually. Each embodiment focuses on describing the differences from other embodiments. In particular, for system or system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and relevant parts can be referred to the descriptions in the method embodiments. The systems and system embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0044] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention are included within the scope of protection of the present invention.

Claims

1. An iron box tightness detection system, characterized by, The application relates to a sealing detection device for iron cassettes. The sealing detection device comprises an iron cassette conveying unit and a differential pressure type sealing detection unit. The iron cassette conveying unit comprises a detection station base and an iron cassette conveying line provided with a detection station entrance and exit. The differential pressure type sealing detection unit comprises a gas source, a differential pressure sensor, a test end assembly and a reference end assembly. The test end assembly comprises a test gas path and a test sealing cover, and the reference end assembly comprises a reference gas path and a sealed reference cavity.

2. The iron magazine tightness detection system according to claim 1, characterized in that, The test gas path and the reference gas path are arranged in parallel and are connected to the gas source.

3. The iron magazine tightness detection system according to claim 2, characterized in that, The test sealing cover is sealed at the top and the side and is open at the bottom.

4. The iron magazine tightness detection system according to claim 1, wherein The test sealing cover is arranged above the detection station base through a lifting mechanism.

5. The iron magazine tightness detection system according to claim 4, wherein The lifting mechanism is used for driving the test sealing cover to descend to cover the iron cassette to be detected after it is determined that the detection station base has the iron cassette to be detected.

6. The iron magazine tightness detection system according to claim 1, wherein The test sealing cover and the detection station base form a sealed test cavity.

7. The iron magazine tightness detection system according to claim 6, wherein The gas source is used for simultaneously performing vacuumizing operation on the sealed reference cavity and the sealed test cavity after the sealed test cavity is formed.

8. The iron magazine tightness detection system according to claim 6, wherein The test pressure difference of the differential pressure sensor is read after the internal pressure of the sealed reference cavity and the sealed test cavity is stabilized.

9. The iron magazine tightness detection system of claim 1, wherein It is determined that the iron cassette to be detected is sealed badly when it is determined that the test pressure difference exceeds a pressure difference threshold.

10. The iron magazine tightness detection system according to claim 9, wherein The test end assembly further comprises a first pressure divider tank, and the reference end assembly further comprises a second pressure divider tank. The first pressure divider tank is connected to the test gas path through a first pressure divider valve, and the second pressure divider tank is connected to the reference gas path through a second pressure divider valve. The first pressure divider valve and the second pressure divider valve are both normally closed pressure divider valves. A first pressure stabilizing valve is arranged on the test gas path, and a second pressure stabilizing valve is arranged on the reference gas path. The first pressure stabilizing valve and the second pressure stabilizing valve are both normally open pressure stabilizing valves. The test gas path and the reference gas path are connected to a gas filling valve. The gas filling valve is connected to a test pressure sensor. The gas filling valve is connected to an exhaust valve. The iron cassette conveying unit further comprises a feeding mechanism. The feeding mechanism is used for driving the iron cassette to be detected to switch positions between the detection station base and the iron cassette conveying line through the detection station entrance and exit. The feeding mechanism comprises a suction disc and a push-pull air cylinder.

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