I have a supplier that believes that dry N2 will desiccate
better than dry air. I don't think oxidation is a factor with this
problem. The N2 would be pumped through/around this item so it
would get a continuous flow/rinsing. If the dry air is just as dry
as the N2 (dew point not Mountain Dew point!) would the drying affect be
the same?
My first recommendation was for a vacuum bake but for this item (for
reasons I can't go into here) that's not possible. I may be able to
have them at least do a bake and flush with dry air or N2.
At 12:13 PM 10/29/2002, you wrote:
Why N2? You would get exactly the
same effect with dry air. However, be
warned: if the air or nitrogen becomes humid, you will reach an
equilibrium state between the parts and the air or gas, not perfect
dryness. You will need several successive "rinses" of dry gas
to achieve
low levels and probably storage in large volumes, compared with the
volume of the parts. The only advantage of N2 over air is if you wish
to
avoid an oxygen reaction, such as oxidation of reactive metals, and
this
has damn-all to do with moisture (well, almost :-) ).
Brian
Gregg Klawson wrote:
Hello Technet,
A question came up this morning as to whether nitrogen could be used as
a
drying agent for PWBs, components, etc. I know nitrogen is used as
a fill
gas for dry boxes, bags and to provide a dry atmosphere for
component
testing. I don't have a feel for the physics of using nitrogen to
dry
something out. We have a situation where baking at high
temperatures may
not be practical but immersion in a nitrogen atmosphere is. Any
ideas,
references would be appreciated.
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