Nitrox mixing at home...

[matt_unique]

I often wonder how many people think 02 is flammable? I bet a poll with this question would be interesting...



--Matt

 

[Rick Inman]

I pay $38 for Aviation grade.

I often wonder how many people think 02 is flammable? I bet a poll with this question would be interesting...

Well now you've spoiled it.

 

[Thalassamania]

I pay $38 for Aviation grade.

Yes, my O2 was very cheap. I forgot about the deal I was not supposed to talk about.<G>

 

[ClayJar]

Okay, since most O2 cylinders I've seen have had a service pressure of 2015 psi, I'll assume that is the case with your 250cf cylinder.

Now, take the desired fraction of O₂ in your final mix, along with the 3000 psi service pressure of your AL80s, and find the initial pressure of pure oxygen required for that mix. Then plug that pressure in with the initial pressure and internal volume of the oxygen cylinder, along with the total final volume, and tada! Or, to put it into an equation:

P_{O2 cylinder} * V_{O2 cylinder} = (f_O2 - 0.21) * P_fulltank * (V_{O2 cylinder} + n * V_tank)

...that is...

2015 psi * 250 cf * 14.7 psi / 2015 psi = (f_O2 - 0.21) * 3000 psi * (250 cf * 14.7 psi / 2015 psi + n * (77.4 cf * 14.7 psi / 3000 psi))

...solving for 'n' and simplifying...

n = 3.2299 / (f_O2 - 0.21) - 4.8088

So, that's how many AL80 fills you could get out of your 250 cf, 2015 psi O₂ given a desired fraction of oxygen in your final mix. Note that there's nothing in there about how you do it, only about the service pressures of the source and destination cylinders, their volumes, and your desired fraction of oxygen. 32%? 24 AL80s and change. 36%? 16 AL80s and then some. 40%? 12. 76.6%? Well, you could get a grand total of 1 AL80 out of it.

If you hooked up 'n' tanks in parallel and let them reach equilibrium with the source cylinder, you'd have 'n' tanks ready to be topped off with air to get your final mix. If you hooked them up one at a time, you would end up with the same. If you're confused by this, I'll be even more apprehensive about your asking questions than I already am. Don't discover your true potential by turning it kinetic.

 

[The Horn]

What is that? Medical grade and industral sure, but aviation hmm anyway Idustrial is in the 99.9 % is the aviation like 100.00 on the money?

Anyway I like the treads where there is always the element of danger and some replys are the "you can't do that" response.

How about a poll on doing something because some one told you that you couldn't !

I ended up building my own house

 

[matt_unique]

I pay $38 for Aviation grade.

Well now you've spoiled it.

Ha ha, well I did not want to embarrass people.....

--Matt

 

[JeffG]

I often wonder how many people think 02 is flammable? I bet a poll with this question would be interesting...



--Matt

Lots and lots.

 

[Rick Inman]

What is that? Medical grade and industral sure, but aviation hmm anyway Idustrial is in the 99.9 % is the aviation like 100.00 on the money?

From THIS thread:

- while aviation O2 is on paper drier, and welding/industrial cleaner, than medical O2, in real life they are all pretty much the same.

 

[matt_unique]

Lots and lots.

Agreed....

--Matt

 

[Rick Inman]

Aviation Grade burns higher.