Any substance has three forms: solid, liquid and gaseous, and gaseous state is a special state in the existence of matter.It has neither a certain shape nor a certain volume. Its shape and volume depend entirely on the container containing the gas.How to determine whether a container is in good condition is commonly used in developed countries“Water inspection”（“Water inspection”Refers to the fact that manufacturers adopt“Leak detection by immersion in water”to find unqualified workpieces); the equipment is simple,  The results are intuitive, the detection accuracy and efficiency are low, and human factors have a greater impact, making it impossible to achieve automatic quantitative leak detection. At the same time  It will also bring moisture, rust, impurity infiltration and other adverse effects to the workpiece, as well as cumbersome post-processing of water (or oil) on the surface of the test piece. Some products are even not allowed to be tested by this method, such as electronic and electrical components, etc.In the mid-to-late 1970s, in order to overcome the“Water inspection”The process has some disadvantages caused by the follow-up operations of the workpiece; research has begun to replace“Water inspection”New technology and new equipment.Since the early 1990s, motorcycle engine blocks, automobile engine blocks, radiators, brake systems, evaporators, gas appliances, etc. have used clean and dry air as the working medium to test the cavities of workpieces; the technology for sealing performance testing has matured, and some corresponding testing equipment has come out one after another.

Air tightness detectorIt is also called a leak detector or a leak detector; it has a wide range of applications, such as the mobile phone industry, auto parts industry, new energy industry, home charging, smart wearables, audio industry, security lighting, medical equipment industry, wire connection industry, other industries, etc. Next, Hairui Technology will briefly talk about the importance of air tightness detectors for the new energy battery industry.

Picture: HC Classic Series Instruments

The main components of electric vehicles are composed of three parts: motor, battery and electronic control.Once the high-voltage working parts of electric vehicles such as batteries and motors are flooded, leakage and short circuit problems may occur. Therefore, the protection level of electric vehicles must reach IP67 waterproof level (the first number after IP is the dustproof level, and the second number is the waterproof level).

New energy vehicles are driven by hydrogen power and power batteries, and the safety requirements for the components involved are higher, especially new energy battery packs.The air tightness detector test of the new energy battery pack is mainly divided into the air tightness test of the upper casing, the lower casing, and the final assembly; for the air tightness test of the upper and lower casings, it must meet the leakage requirements of the air tightness after final assembly, that is to say, the sum of the independent leakage rates of the upper casing and the lower casing must not exceed the leakage requirements of the finished battery pack; due to the characteristics of the new energy battery pack, the inflation pressure of the battery pack air tightness test cannot be too high.

The detection principle of Hirays Technology is the pressure decay method, which means to pressurize a product and observe the pressure change of the gas.There are two situations here. One is that the product itself has an inflation hole. We will directly inflate and pressurize the product, then cut off the air source and observe the changes in gas pressure. If the pressure drops, it means that the product is leaking. If it does not drop, it is good.The second type is that the product does not have an inflatable hole. We need to make a sealed cavity that is the same size as the product shape and specifications, that is, an abrasive mold, and try to fit the product as much as possible, because the detection results will be more accurate. Then pressurize the gas, and the gas will fill the space between the product and the abrasive mold. Then we also cut off the air source and detect whether the gas pressure has dropped. If there is a leak, the gas has leaked into the product. If there is no drop, it is good.

Picture: HL Leader Series Instruments

Hirays Technology is based on the research and development, production and sales of air-tight leak detectors and air-tight leak detection systems and provides one-stop air-tight leak detection solutions.Combined with the application needs of the air-tight testing market, we develop and produce differential pressure, direct pressure, and flow-type air-tight leak detectors with high sensitivity, high resolution, good stability, excellent quality, excellent performance, and easy operation, supporting various products and fully-automatic air-tight leak detection systems for various industries including air-tight leak detectors, tooling fixtures, automated control, human-computer interaction, and safety protection, as well as customized pressure testing, flow testing, leak detection and other solutions for customers.

The above content is an introduction to the development of air tightness testing and its importance in the new energy battery leak detection industry. I hope it will be helpful to you.

Related reading:How to determine the test air pressure and test parameters of air tightness testing equipment