Re: How much moisture is absorbed into a stainless steel tube

[the following answer was actually posted by Rick Becker]

Matthew,
 
"Absorbed" is not the word or concept you need to think about.  "Adsorbed"
is.
Water vapor is difficult to avoid in vacuum systems.  The molecules cling
tightly to any surface that has been exposed to atmosphere, corrupting
accurate results for an extremely long time.    I am not familiar with your
apparatus, but tt sounds as though the cure for your problem would be to
heat the tube along its length to something well over 100C when purging your
system prior to your runs.  This will give the water molecules enough energy
to break free of the surface, and be carried downstream, leaving a water
free surface.  Please contact me if you have further questions. 

Rick Becker