Volume of Al 80

[ianr33]

So, if I fill an Al 80 to 3000 psi then let all that air back out again I get a total of 77.4 cu ft of air.

What volume of gas would I get if I did it with helium instead?

 

[Wookie]

Volume is volume whether measured in liters or cubic feet. About 77.4 cubic feet. Is this a pound of feathers or pound of lead question?

 

[decompression]

Al 80 is simply a name, actually capacity is 77.4 as mentioned. Volume of a gas is volume of a gas.

 

[mala]

are they called ali 80's because thats how much gas they carry at max wp?

so different pressure ali 80's are all different sizes?

just asking as it seems really complicated to me used to the metric world.

thanks

 

[ianr33]

You all obviously live in an Ideal world ...............

 

[Fishpie]

The 3300psi Catalina 80's are true 80 cf I believe.
Very nice tanks and if anyone has any in S Florida I will swap 3 regular 80's to 2 Catalina 3300psi 80's and 2 to 1 for the 90's.

 

[Wookie]

are they called ali 80's because thats how much gas they carry at max wp?

so different pressure ali 80's are all different sizes?

just asking as it seems really complicated to me used to the metric world.

thanks

They are called 80's because that's easier to say than 77.4's. Try saying 12.2 liter 232 bar cylinder and you'll know why we call them 80's over here.

 

[Scared Silly]

Frank has it about right, they are 80s because of marketing. Calling them an 80 makes seem like they held 10% more than an LP72. Add to that the rust issue gave the marketing dept. something to crow about.

 

[clownfishsydney]

A 12.2 litre 232 bar cylinder is actually a 100 cubic foot tank, not 80 cf. 12.2 x 232 = 2830.4 litres. There are 28.3 litres per cubic foot, therefore there is exactly 100 cf in a 12.2 litre tank filled correctly.​

 

[4sak3n]

A 12.2 litre 232 bar cylinder is actually a 100 cubic foot tank, not 80 cf. 12.2 x 232 = 2830.4 litres. There are 28.3 litres per cubic foot, therefore there is exactly 100 cf in a 12.2 litre tank filled correctly.​

If you are responding to Wookie, I believe that he mentions a 12.2L 232 bar cylinder as an example of a metric cylinder whose actual volume gets shortened in order to save breath in a manner similar to the way in which Ali80s are shortened. I do not think that he was actually saying that they hold similar volumes of gas at all.

i.e. saying: "Seventy seven point four cubic feet," is just as onerous as saying: "Twelve point two litres with working pressure of two hundred and thirty two bar," rather than: "Ali80s are the same as steel 12s."

---------- Post Merged at 12:28 PM ---------- Previous Post was at 12:10 PM ----------

So, if I fill an Al 80 to 3000 psi then let all that air back out again I get a total of 77.4 cu ft of air.

What volume of gas would I get if I did it with helium instead?

Another thought experiment: would you get out all 77.4cft though? I guess what I am asking is: "Is the volume of gas at ambient pressure (14.7 psi or whatever STP is at sea level) counted towards your final volume?"

So, if you completely empty a cylinder, is the gas you get out ~77cft and the gas left in the cylinder ~0.4cf or do you get out the full advertised 77.4cft with ~0.4cft left over inside the cylinder?

The former, right?