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Shimadzu Review 79[3・4] (2022)
Abstract
In recent years, a variety of leak testing methods have been defined in JIS and NDIS standards. One such method for high-precision and high-speed leak testing is helium leak testing. Helium leak detectors used for testing can quantita tively measure leakage rate values that do not vary depending on the operator. The measurement principle for helium leak detectors is to ionize the helium tracer gas leaked from the specimen in an analyzer tube and then detect only the helium gas ions by isolating them with a magnetic field using mass spectrometry. Helium gas has a very low background signal level because its concentration in the atmosphere is an extremely low 5.2 ppm and helium leaks are easy to detect because helium is a single-atom molecule with a very small molecular size that can easily pass through minute defects and pores in components. Furthermore, it is an inert gas that does not affect test specimens and is harmless to humans. That makes helium an ideal tracer gas and enables higher precision and higher speed leak testing than other leak testing methods. Consequently, it is used in many automated production lines for electric vehicle components. However, lately the demand for helium gas has been increasing year after year, resulting in a supply problem because more than 90% of the current helium gas supply is produced in the United States, Qatar, and Algeria, and it is a rare resource that can only be refined at certain natural gas fields. In response to this problem, Shimadzu Industrial Systems Co., Ltd., is proposing a helium recovery system for reusing helium gas used during helium leak testing and a hydrogen leak testing system for leak testing with hydrogen gas, which is widely available and inexpensive.
This article describes such leak testing systems developed and manufactured by Shimadzu Industrial Systems Co., Ltd., a manufacturer of leak detectors, based on leak testing technologies that enable high-precision and high-speed leak testing.
Shimadzu industrial systems Co., Ltd., Kanagawa, Japan
*The information contained in Shimadzu Review has not been modified since the original publication date. Please be aware that in some cases, products mentioned within the articles are no longer available.