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Jim Wilkins[_2_] Jim Wilkins[_2_] is offline
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Default Aviators oxygen vs welding or medical oxygen.

"rangerssuck" wrote in message
...
On Wednesday, March 1, 2017 at 11:00:16 AM UTC-5, Jim Wilkins wrote:
"rangerssuck" wrote in message
...
On Tuesday, February 28, 2017 at 12:35:16 PM UTC-5, Neon John
wrote:
On Mon, 27 Feb 2017 19:41:31 -0800, pyotr filipivich
wrote:


I'm still curious as to how one can have compounds in a 100%
or
even 99.9% Oxy environment.

Because commercially pure (medical or welding) gas simply isn't
that
pure. In all but the smallest plants, oxygen, nitrogen and
argon
tanks are filled by boiling that component of liquid air,
separated
by
a fractionation tower. Oxygen contains a little nitrogen and
all
the
compressed gases contain traces of helium.

Research grade (so called "5 9s") gas is made by refining the
commercial grade gas through filters, catalysts and absorbers.
That
gas is quite expensive (I pay $1/liter in 200 liter cylinders
for
neon
for my sign making) and has little commercial use.

John



When medical OX is made, the pump is in a nylon pump and it
squeezes the
oxygen by squeezing a hose from a series of filters into
the
tank.

Except for very small operations such as a hospital refilling
their
own "E" tanks, oxygen is NOT compressed. Much more efficient to
boil
the liquid.

Even when an oxygen compressor is used, it contains no nylon.
The
nylon would diesel on the compression stroke. My experience
with
breathing air and oxygen compressors is that they use a
mica-graphite
compound for seals and piston rings.

John
John DeArmond
http://www.neon-john.com
http://www.tnduction.com
Tellico Plains, Occupied TN
See website for email address

1) So are you saying that they put a measured quantity of liquid
oxygen in a tank, seal it and let it boil off to a known
pressure?

2) is there less expensive neon available? What would be the
consequence (color difference, maybe?) of using it? Just
wondering.

JPB


https://en.wikipedia.org/wiki/Air_separation


thanks. More information I will never use, but it does keep the
brain lubricated.


Good. Try your well-oiled brain on the Riddle of the Sphinx:

What walks on four legs in the morning, two legs at noon and three in
the afternoon?
-Sophocles