Coaxial helium leak detection probe

A coaxial device has been developed which makes it possible to pinpoint a leak in a piece of vacuum hardware or tubing within a space of one‐sixteenth of an inch. The device consists of a delivery tube which directs the helium to a precise spot and a coaxial outer tube which pumps away the excess helium. This arrangement prevents diffusion or drift to a real leak in close proximity of the test area.