Airtightness testing you need to know these, the mainstream 5 kinds of sealing test principle detailed dismantling

Airtightness is directly related to the safe and reliable use of the product, so how to test the airtight waterproof performance of the product?

Nowadays, there are mainly 5 mature and reliable airtightness testing methods in the industry. This article will provide you with a comprehensive analysis of the principles, advantages and disadvantages of these 5 airtightness testing methods, the use of scenarios and cases, a comprehensive interpretation of all aspects of the airtightness measurement technology, in order to enhance your comprehensive knowledge of airtightness testing.

So what does it take to accurately determine how bad a leak is? This brings us to the two important leakage display unit systems in airtightness testing.

I. Water Inspection Act

This method is suitable for products that need to be tested for airtightness in a liquid environment, especially waterproof products.

Pros:

The operation is relatively simple and easy to handle and implement.

You can visualize the bubbles coming up and judge the sealing performance.

Drawbacks:

Only suitable for testing the airtightness of products in liquid environments, not for other media.

The accuracy is average and does not provide precise quantitative measurements.

Applicable Scenarios:

It is mainly applicable to products that need to test waterproof performance, such as electronic products, cell phones, etc.

Represents equipment:

浸水试验箱::It is used to test the product by completely immersing it in water and observing whether bubbles come out to determine its sealing performance.

Drenching Rain Test Chamber::Specifically designed to simulate testing environments under rain conditions, it can simulate different rainfall intensities and durations for evaluating the waterproof performance of products.

Ⅱ.pressure decay method

Also 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 air or liquid supply source is turned off and the change in pressure is observed over a period of time. 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 a good airtight performance.

仪器型号：JC-LZ10020 定量式，被测产品：矿井摄像头，测试压力：60kPa，测试原理：压力衰减法

Pros:

It can provide quantitative pressure change data, leakage rate, and more accurate assessment of the product's airtightness performance.

It is suitable for gas tightness testing of different media and has a wide range of applications.

Drawbacks:

A gas supply unit is required, as well as tooling and fixtures.

For smaller leaks, it may take longer tests to detect them, so patience may be required in some cases.

Applicable Scenarios:

It is mainly applicable to products that require quantitative assessment of airtightness performance, such as outdoor lamps and wiring harnesses. The method can determine the sealing performance of a product by measuring pressure changes and provide relatively accurate results.

Represents equipment:

Positive pressure air tightness tester::The airtightness of a product is evaluated by applying pressure and monitoring the rate of pressure decay.

定量气密性测试仪::Combines pressure decay method and other inspection methods to provide more comprehensive airtightness inspection functions, including pressure change measurement, leakage detection, and more.

III.Pressure change detection method

This is a common method of airtightness testing, where the sealing performance of a product is evaluated by applying pressure and monitoring the pressure change. Pressure gauges or pressure transducers can be used to measure pressure changes to determine the airtightness of the product.

Four-channel safety valve tester，双分析模式：定压力测流量、定流量测压力，带条码扫码枪、压力曲线分析，支持非标定制

Pros:

The operating principle is simple and provides quantitative data on pressure changes, leakage rates.

Can be applied to different media, including gases and liquids.

Drawbacks:

Subject to ambient temperature and atmospheric pressure, calibration and corrections are required.

For smaller leaks, it may take longer tests to detect them.

Applicable Scenarios:

Suitable for products that require quantitative assessment of airtightness performance, such as capillary tubes, valves, die castings, etc.

Represents equipment:

Gas Flow Gas Tightness Tester::Used to measure pressure changes and evaluate the airtightness of products.

IV.Negative Pressure Vacuum Detection Method

This method tests the airtightness of a product by establishing a closed test environment, placing the product inside a vacuum chamber and applying negative pressure to create a pressure difference between the inside and outside of the product. A vacuum pump can be used to extract air and observe the pressure change or monitor the vacuum level to assess the product's airtightness.

仪器型号：JC-FY80 负压式，被测产品：平板显示器，测试压力：-15kPa，测试原理：负压真空检测法

Pros:

With high sensitivity and wide applicability, it can more accurately assess the airtightness performance of products.

Smaller leaks and air leaks can be detected.

Drawbacks:

A closed test environment needs to be set up with high equipment and facility requirements.

A matching negative pressure system is required.

Applicable Scenarios:

It is suitable for products that require high airtightness performance, such as electric shavers, automotive parts, medical equipment, etc.

Represents equipment:

Negative pressure air tightness tester::Used to establish a negative pressure environment to test the airtightness of products. Judge the sealing level of the product by observing the pressure change in the chamber. A rapid rise in pressure indicates that the product is poorly airtight; a stable pressure indicates a good airtightness.

V.gas leak detection

This method evaluates the gas-tightness of a product by applying a gas around the product or test sample and using a leak detector to detect gas leakage. Commonly used test gases include helium and nitrogen, among others.

Pros:

Can detect small gas leaks with high sensitivity.

Precise detection and high degree of automation.

Drawbacks:

Specialized leak detectors are required and equipment costs are high.

The testing process is relatively complex and requires specialized operational skills and experience.

Applicable Scenarios:

Suitable for products that require high sensitivity to small leaks, such as gas containers and piping systems.

Represents equipment:

as ifHelium Leak Detector,Nitrogen Leak Detectoretc., for detecting gas leaks and leak points.

VI. Summary

Through the above analysis of the five airtightness testing methods, we can see that different airtightness testing techniques have their own advantages and disadvantages, and no one method can perfectly take into account the full range of testing needs.

The water test method is simple and direct, gas leakage detection is accurate and reliable, and the pressure method can quantify the leakage rate. For different products, the purpose of testing is not the same.

So.There is no one-size-fits-all testing technology, 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 realize synergistic effects. For example, water testing first checks for obvious defects, and gas leakage testing for detailed verification.