Adixen ASM 142, User Manual

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A 400
Testing methods
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Bombing method
This method is used for sealed objects that cannot be connected
directly to the detector (semiconductors, waterproof watches, etc.).
He
He
part part
Chamber 1 Chamber 2
detector
The part is placed in a chamber containing pressurized helium.
The helium penetrates the part if it has a leak.
The part is then removed from the chamber and placed in another
vacuum chamber which is connected to the detector. The helium
escapes from the part through the leak and produces a signal.
This signal is not a direct measurement of the leak as the helium
pressure inside the part is difficult to determine. Several parts play an
important part such as: the pressurization time, the helium bombing
pressure, the internal volume, the aeration time, the size of the leak.
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