by Yoshio Unno1
Shimadzu Review 78[1・2] (2021)
Abstract
Helium leak detectors are widely used in industry as a highly sensitive and accurate method of testing for leaks. Using helium as a tracer gas, helium leak detectors guide helium leaking from a test piece into an analyzer tube for detection. The extremely low 5.2 ppm concentration of helium in the atmosphere results in a very low background signal and the small size of helium molecules allows them to pass through even tiny holes for leak detection. Furthermore, with no toxicity or flammability, the safety and other characteristics of helium make helium ideally suited as a tracer gas for leak testing. Consequently, demand for helium gas has been increasing year after year. On the other hand, helium has a supply problem. Over 90% is produced in the United States, Qatar, and Algeria because it is a rare resource that can only be refined at certain natural gas fields. Therefore, Shimadzu Industrial Systems, which is a helium leak detector manufacturer that also offered helium leak testing systems for many years, recently developed a new helium supply and recovery system that reuses the helium gas used for testing. The company also offers user support for switching to using hydrogen as a tracer gas for leak testing. This article describes the corresponding products.