Airtightness Tester是用于检测产品气密性的仪器，它通过测量产品在一定压力条件下泄漏量/泄漏率的大小来判断产品是否合格。
A video to read the product airtightness qualified judgment standard
What is a good airtightness? This is a question we often think about in our daily airtightness testing work.Gas-tightness performance reflects whether the product is subject to gas leakage during use.
过去几年，我们一直在从事Airtightness Tester的研发工作。通过这些年的工作经验，JCGK 深刻理解到判断产品气密性良好与否的重要性。我想通过这篇文章与大家分享我在这个过程中积累的一些经验与见解。
Ⅰ.What are leakage rates and leakage volumes?
Leakage (Pa) and leakage rate (ml/min) are essentially the same concept, and this leakage value is equivalent to defining a threshold between OK and NG for a product.They are important indicators that reflect the sealing performance of a product under certain pressure conditions, and are the main benchmark and basis for determining whether a product is airtight or not in our process production, as well as the basis for the instrument to determine whether a product is airtight or not, and airtightness test OK pass or NG.
Leakage is the volume of gas leaking through the product per unit of time in pascals (Pa);
Leakage rate is the ratio of the volume of gas leaking through the product per unit of time to the volume of the product in milliliters per minute (ml/min).
Ⅱ.How to determine whether the product airtightness meets the process requirements?
As noted above.Whether a product is airtight or not is determined by the value of the leakage amount. This leakage indicator is not included in the instrument, but is set by the technician.The instrument will use this value as a criterion for judging whether the product passes or fails the test process:
If the leakage value reaches or exceeds the preset leakage value, the instrument will consider that the product fails and display a red NG indication on the interface; if the value stays within the set range, the instrument will consider that the product passes and display a green PASS indication.
For example, if we set the leakage amount to 30Pa, products with leakage amounts of 30Pa or more will be judged as NG, while products with leakage amounts of less than 30Pa will be judged as pass.
III.Setting values for leakage volume and leakage rate
The criteria for determining whether a product is leaking or not should come from the reference leakage amount provided by the customer. If the customer does not provide the data, we need to test and obtain the data ourselves.
Methodology for deriving leakage:
- Take a group of products (say 10) that we have ensured are airtight and test them and record the leakage values.
- Take another set of defective products with leaks (e.g., 10) and test them and record the leakage values.
- The above test we got two sets of leakage values, which we analyze:
- Let's start by looking at the qualifying products, and assuming that the qualifying products all have leakage values of 10, 8, 12, 15 Pa... and then none of the maximum values will exceed 20 Pa.
- Let's look at the data for the defective product and assume that the data for the defective product might be 50, 100, 300 Pa... the data far exceeds that of the qualified product.
Then we can set the value of 20-25Pa as the judgment standard of leakage. At the same time through the above experiments we also have a basic understanding of the qualified and unqualified product data.
IV.Product airtightness conformity judgment
For products whose leakage values in testing are well above the specified thresholds, they can basically be judged as leaking products. However, for some products with leakage values very close to the threshold, theIf the leak reference is defined as 20Pa and the test values show 21Pa or 25Pa, can we be sure they are leaking?
Not necessarily.It can also be caused by factors such as temperature changes, product shape, etc. for example.To be on the safe side, these products are recommended to be taken out first and go for determination later. If the subsequent testing found that these products are qualified and more, then it is possible that the previous leakage determination standard test sample size is not large enough, resulting in a little bias in the data. We can appropriately modify the leakage amount or leakage rate standard.
V.Summarize
Through these years of groping and summarizing some experience, I hope to be able to provide some reference for you to judge and control the airtightness performance of products. Of course, this is a very complicated subject.Judgment criteria also need to be set in relation to the specific product and use environment.如果您在进行气密性检测时遇到任何问题，请咨询Airtightness Tester制造商或专业人士，如 JCGK Precision Engineering AirtightnessThe
JCGK has become an industry leader in airtightness testing technology and solutions. We not only provide precise and reliable testing instruments, but also have accumulated valuable experience in judgment standards and quality control. These achievements have helped to improve the performance and reputation of our customers' products. Looking ahead, JCGK will continue to innovate and work with more customers and partners to promote technological innovation in the industry and create greater value!
