Outlook for the Development of Air Tightness Testing Equipment

Air tightness testing equipment mainly uses purified dry air as the working medium to test the sealing performance of cavities with a certain internal volume, and it can also be used in series or parallel configurations for other tests. However, it must not be used directly to test gas-liquid two-phase flow systems or gas-solid two-phase flow systems; otherwise, incorrect test results may be obtained or irreparable damage may be caused to the instrument.

The detection accuracy or sensitivity of air tightness testing equipment is closely related to the pressure transmitter used in the instrument. Specifically, it is related to the resolution error of the pressure transmitter. For example, the resolution error of current pressure transmitters ranges from 0.01% to 5%. The smaller the error, the higher the detection accuracy. It is also related to the range of the sensor. For example, the smaller the range, the higher the accuracy. At the same time, it is related to the processing capability of different brands of PLCs, because the main digital processing capability still depends on the PLC. The pressure transmitter is responsible for providing the analog air pressure value to the PLC, and the PLC then converts the analog value into digital data. Theoretically, the detection accuracy of differential pressure can reach 1-5 PA, while the detection accuracy of direct pressure is above 5 PA. Some manufacturers claim an accuracy of 0.1 PA, but that is only achieved through software manipulation and such accuracy cannot actually be achieved.

Air tightness testing equipment is a state monitoring and detection device that can be used to form a control alarm system or dedicated testing equipment. For example, an air tightness tester can be combined with custom fixtures to create a dedicated production line machine for testing the air tightness of workpieces. Common examples include the cylinder head leak testing machines, clutch cover (or assembly) leak testing machines, cylinder block leak detectors, and transmission housing leak testing machines manufactured by our company for motorcycles and automobiles.

Based on an analysis of the current state of development in air tightness testing equipment, the air tightness tester is connected to a test chamber specifically designed to accommodate the package to be inspected. The package is placed in a test cavity that is to be evacuated. Single or dual vacuum sensor technology is used to monitor the test chamber at two levels of vacuum, and also to monitor vacuum changes over a predetermined test period. Changes in absolute vacuum and relative vacuum imply the presence of leaks and defects in the package.

In the next 10 to 15 years, we should fully leverage China's rapid economic development and huge market advantages, vigorously promote research into the application of new technologies and new processes in instruments and meters, and master key technologies such as the design and production processes of various instruments and meters, so as to shorten the overall gap between China's instrument and meter industry and the international level to 3 to 5 years, with about 30% of products reaching the advanced international level of the same period, the supporting capacity of domestically produced instruments and meters in major projects reaching over 85%, and their share of domestic market demand exceeding 75%.

Air tightness testing equipment has been widely used in China since the 1990s and has become essential equipment for testing industrial products. With the development trends of industrial automation and industrial upgrading in China, precision testing instruments developed for specific applications will have significant market potential in the field of industrial testing. At the same time, for China to become an industrial powerhouse, it must also attach importance to R&D and innovation. That concludes the analysis of the current state of development of air tightness testing equipment.