(1) Sure Spraying of Helium
Prevent helium from being blown by airflow. ※Require care not only at spray method but sniffer method.
(2) Order of Finding Leak Point
Helium moves upward because it is a lighter gas. Spraying much helium makes it difficult to find a leak point.
※At spray method, top-to-bottom.At sniffer method, bottom-to-top.
(3)Time constant in leak test
According to the shape of the test object, it can take a while to detect helium.
At the sniffer method, the response rate depends on the hose length.
(4) Quantity of Helium in Leak Test
(5) Environmental Consideration for Test by Sniffer Method
At the sniffer method, the minimum detection limit depends on the helium concentration (background) in the atmosphere.
(6) Proper Use of "Zero Adjust Function"
"Amount of change' of helium is 'leakage quantity." Therefore possible to display the exact leakage rate by 'zero adjust function' that sets the background value to zero.
No need for 'zero adjust function' in case that there is several digits difference between the background and the judgment value.'Zero adjust function' should be activated when the background is stable.
