SpudFiles

hey there!!
I have a 60g CO2 cardrige which is empty and i wanted to know, how much pressure could i put in to use it as a storage container for a mini pneumatic..? The reading shows
60g CO2 MV 233 MP 295 MAX
01 129 MP 291 MIN

I've" read that 1 gram of CO2 makes 1L of gas when at room temperature. 60 grams make 60 liters, confined in a 3cm dia. for 11cm in length. that makes 77 ml, so 60 L of gas in 77 ml makes 800 bars.....isn't that a bit high? normaly, 850 psi CO2 makes 3000 psi air, so if if have 4200 psi CO2 (290 bars) i will have 14000 psi air.....so 1000 bars...
I have two values.....which one is the good one..?

1 gram of CO2 produces about HALF a litre of gas at atmospheric prssure.

CO2 liquifies at 800 (or so) psi, so at those 800 psi, the gas'll start to turn to liquid, which is why it stores well.

Those cartridges are typically rated to a little less than 300 bar - yours would appear to be good for 295 bar.
However, you'll never reach that pressure.

To fit a cartridge like that, I would:

Start by finding a thread that'll fit the cartridge, then drill the opening on the cartridge a bit wider for more air flow (and thus power), link that to a small but tough piston valve, and make a smallish pneumatic from that.

With the right type of pump (perhaps a mountain bike shock pump) you could get up to 300 or more psi, which'll give a worthy amount of power.

Does that help?

yep, that helps a lot!!! but....i still have a question, what is this CO2 / air equivalence, the hum 850 psi CO2 = 3000 psi air? if y cartrigde is rated 295 bars CO2? I seem to be confused...for me, a psi is a psi, a bar is a bar...there's something to do with gaz density...

There is no equivalence. They are identical in pressure terms.

1 psi CO2 = 1 psi air.

Air is however stored as a highly compressed gas, as it doesn't liquify within easy limits - this is done at about 3000 psi.

CO2 is stored at a liquid in the 800 - 850 psi range.

I imagine that's where your numbers come from.

The CO2 cartridge is rated many times in excess of the 50-60 bar that CO2 is normally at because CO2's liquification pressure is highly dependant on temperature, and thus the safety margin is needed to compensate for accidental dropping, or high temperatures.

In terms of the density of the gasses, that doesn't really matter.

Useful?

Lol thx for all!!!
The time we're in the safety pressure uses, one tube of 8mm OD copper, slided in a 10mm OD pipe will resist 60 bars? (30 for each tube?)

8mm copper has a burst pressure (burst pressure, not rating) of about 490 bar.

10mm has a burst pressure of 350 bar.

I'd reckon that the 8mm could take it easily on it's own. With the typical 3:1 safety ratio, that would be rated at about 165 bar.

Throwing an extra 2:1 on that, and it's still above your 60 bar by more than 25%.

Besides, 8mm copper and 10mm copper don't sleeve exactly. If you put solder between them, that would help if you really need to sleeve it.

hey man, a lot of thanks!! and a few spudbux for you!!!
thanks a lot!!