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<font color='#0000FF'>Hello all,

One of my buddies asked me about buying 300bar cylinders for trimix diving, and I advised him not to due to Van der Waal's Equation. He also asked TDI inst and told him
[b said:
Quote[/b] ]It is fine to put Trimix in a 300 Bar cylinder.  The concern you might have with High Pressures gasses in if were to fill O2 above 200 bar, but Trimix is fine.
Who's wrong then ? As I always understood it ideal gas laws above 200bar are not stable and so with a 300bar trimix fill you will never be sure what you have in it! Does anyone here dives this way?

Regards

Pierre
 

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Discussion Starter · #4 ·
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<font color='#0000FF'>Hello again,

Anyone here uses 300bar trimix fills and if yes do you mix them or your diving shop? What are the pro and cons of using 300bar trimix. I always tought and was taught that normally trimix is dived up to 200bar?!
 

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<font color='#0000FF'>Hi Pierre,
One of the possible reasons for this is the nature of the gasses in Trimix.
Oxygen and Helium molecules compress at different rates, so 100 bar of Oxygen does not give the same amount of litres of gas as 100bar of Helium. (there would be less helium).
However, a GOOD gas blender can still get it right, so I dont see why not


Stu.
 

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HI Pressure E
i think that you are right, because if the filling pressure is 300 bars we still can get the right mix manually or by the use of soft ware (proplanner for example):cool:
 

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This came up once before and I've been looking into it.

Some findings I have suggest that over 200 the mix is difficult to control due to the molecule size, as PressurE mentioned.

However, it is perfectly possible if you have experience and in any case...you can check the blend and adjust accordingly.

It's not an issue if you have the right person doing the fill.

I'm not Trimix qualified but have friends who are....please correct me if what I've said i wrong.

Regards.

Graham
 
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