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 airtightness measurement technology, in order to enhance your comprehensive knowledge of airtightness testing.
-1, water test methodThis method is suitable for testing the airtightness of products in a liquid environment, especially waterproof products.
Advantages:Relatively simple operation, easy to operate and implement.
You can visualize the bubbles coming out and judge the sealing performance.
Disadvantages:Only suitable for testing the airtightness performance of the product in a liquid environment, not applicable to other media.
Accuracy is average and does not provide precise quantitative measurement results.
Applicable Scenario:Mainly applicable to products that need to test the waterproof performance, such as electronic products, cell phones and so on.
Representative equipment:Water immersion test chamber: Used to test the product by completely immersing it in water and observing whether there are bubbles coming out, so as to judge its sealing performance.
Rainfall Test Chamber: Specially designed to simulate the testing environment under rain conditions, it can simulate different rainfall intensity and time for evaluating the waterproof performance of products.
-2, pressure decay methodAlso known as the pressure drop method, is a commonly used airtightness testing method, applicable to different media airtightness testing.
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. Conversely, if the system's pressure changes very little, 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:The cost of testing is relatively high.
For the small leakage test of large-volume products, the airtightness tester is difficult to detect, mainly due to the medium of compressed air, which will be affected by temperature, humidity, and compression variables and other factors.
Applicable Scenario:Mainly applicable to products that need to quantitatively assess the airtightness performance, such as outdoor lamps, wiring harnesses and so on.
Representative Devices:Direct Pressure Airtightness Tester: Evaluates the airtightness of a product by applying pressure and monitoring the rate of pressure decay.
Quantitative Airtightness Tester: Combines the pressure decay method and the volumetric testing method to provide a more comprehensive airtightness testing function, including pressure change measurement, leakage detection and so on.
-3, gas flow detection methodThis is also a common method of gas tightness testing, 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 principle of operation, 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, smaller scope of application.
Applicable Scenario:Applicable to capillary tube, valve, die casting, etc.
Representative Equipment:Gas Flow Gas Tightness Tester: Used to measure changes in flow rate, assess the gas tightness of the product, as well as the ventilation flow rate.
-4, Helium Mass Spectrometry Leak DetectionThis method assesses 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:Specialized leak detector is needed, and the cost of equipment is high.
The detection process is relatively complex, requiring 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 leak points.
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 full range of testing needs.
Water testing is simple and straightforward, gas testing is accurate and reliable, and pressure testing can quantify leakage rates. The purpose of the test is different for different products.
So, there is no universal detection 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 will check for obvious defects first, and a gas leakage test will provide 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