Nowadays, there are mainly 4 kinds of mature and reliable airtightness testing methods in the industry. Next, we will provide you with a comprehensive analysis of the principle, advantages and disadvantages of these four airtightness testing methods, the use of scenarios and cases, an all-round interpretation of all aspects of the airtightness measurement technology, in order to enhance your comprehensive knowledge of the airtightness test.
Mainstream airtightness testing
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1, the water test methodThis method is suitable for the need to test the airtightness of the product in the liquid environment, especially waterproof products.
Advantages:
The operation is relatively simple, easy to operate and implement.
You can visualize the bubbles coming out and judge the sealing performance.
Disadvantages:
Only suitable for testing the airtightness of the product in a liquid environment, not applicable to other media.
Accuracy is average and does not provide precise quantitative measurements.
Applicable Scenarios:
Mainly applicable to products that need to be tested for waterproof performance, such as electronic products and cell phones.
Representative equipment:
Water immersion test chamber: Used to completely immerse the product into the water for testing, to observe whether there are bubbles coming out, so as to determine its sealing performance.
Rainfall Test Chamber: Specially designed to simulate the testing environment under rainfall conditions, it can simulate different rainfall intensities and time, and is used to evaluate the waterproof performance of products.
Water Test Method
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2, Pressure Decay MethodAlso known as the pressure drop method, it is a commonly used airtightness testing method for different media.
In the pressure decay method, a certain pressure is first applied to the product or system to be tested, and the initial pressure value is recorded. Then, the gas or liquid supply source is turned off and the change in pressure over a period of time is observed. If the pressure in the system drops rapidly, there may be a leak or poor sealing performance. On the contrary, if the pressure of the system changes very little, it means that the product has good airtight performance.
Advantages:
Provides quantitative pressure change data, leakage rate, and a more accurate assessment of the product's airtightness.
Suitable for gas tightness testing of different media, with a wider range of applications.
Disadvantages:
Testing costs are relatively high compared to older devices.
For large-volume products of small leakage test, airtightness tester is difficult to detect, mainly due to compressed air as a medium, will be subject to temperature, humidity, and compression variables and other factors.
Applicable Scenarios:
Mainly suitable for products that need to quantitatively evaluate the air tightness performance, such as outdoor lighting, wiring harnesses and so on.
Representative Devices:
Direct Pressure Airtightness Tester: Evaluates the airtightness of a product by applying pressure and monitoring the pressure decay rate.
Quantitative Tightness Tester: Combining the pressure decay method and the volumetric testing method, it provides a more comprehensive air tightness testing function, including pressure change measurement, leakage detection and so on.
Pressure decay method
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3, gas flow detection methodThis is also a common service lack of sedan chair airtightness detection method, by applying pressure and monitoring the pressure change to assess the sealing performance of the product. Pressure gauges or pressure sensors can be used to measure pressure changes to determine the product's airtightness.
Advantages:
Simple operation principle, can test the air tightness of the product as well as the ventilation flow.
Can be applied to different media, compressed air / nitrogen, etc..
Disadvantages:
Higher cost and smaller application range.
Scenario:
Suitable for capillary tube, valve, die casting, etc.
Representative Devices:
Gas Flow Gas Tightness Tester: Used to measure flow rate changes and assess the gas tightness of products, as well as the flow rate of ventilation.
Gas Flow Detection Method
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4, Helium Mass Spectrometry Leak Detection MethodThis method evaluates a product's gas-tightness performance by applying a gas around the product or test sample and detecting gas leaks using a leak detector. Commonly used detection gases include helium and nitrogen.
Advantages:
Tiny gas leaks can be detected with high sensitivity.
Precise detection, can find the leak more accurately.
Disadvantages:
Requires specialized leak detector equipment, higher equipment costs.
The detection process is relatively complex and requires specialized operating skills and experience.
Applicable Scenarios:
Suitable for products that require high sensitivity to small leaks, such as gas containers and piping systems.
Representative equipment:
For example, helium mass spectrometer leak detector is used to detect gas leaks and leakage points.
Helium mass spectrometry leak detection
Through the above analysis of the four airtightness testing methods, we can see that the different airtightness testing techniques have their own advantages and disadvantages, and there is no one method that can perfectly take into account the needs of the whole dress wide-angle testing.
Water testing is simple and straightforward, gas testing is accurate and reliable, and pressure testing can quantify leakage rates. The test purpose is different for different products.
So, there is no universal testing technology, the only according to the product characteristics, choose a single or a combination of technical solutions, in order to take into account the test requirements and economic benefits. At the same time, different technologies can also complement each other to play a synergistic effect. For example, a water test can be used to check for obvious defects, and a gas leak test can be used for detailed verification.
To learn more about the detailed gas tightness testing program and application cases, please pay attention to the Precision Industrial Technology Gas Tightness