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Jamesmb
08-26-2007, 20:38
I remember seeing a table for a specific tank denotating the cubic feet at various psi's. Would anybody have that info or a forumla to calcualte this?

Thanks,

James

skdvr
08-26-2007, 21:57
Just take your tank size in cu. ft. and divide by the rated full fill pressure the answer that you get is how many cubic feet of air for each pound of air.

Lets say that you have a AL 80 that is full at 3000 PSI

80/3000 = .026666667 We will just say that the answer is .0266

Then if you have 1000 PSI left in your tank all you do is multiply 1000 x .0266

1000 x .0266 = 26.6 cubic feet of air in the tank.

What is helpful to know is the actual amount of air in the tank when full. An AL 80 acutually only has 77.4 cubic feet of air.

The math is pretty simple but I do have this Excel spread sheet that you can adapt to your own needs. Mine is for my AL 80's and the HP 130

Well I was going to attach it but I cannot attach an Excel Document. If you cannot create your own just shoot me a PM with your email address and I will email it to you.

Phil

Flatliner
08-26-2007, 22:17
Except and AL 80 isn't REEEALY 80 at working pressure, close but...

skdvr
08-27-2007, 07:30
What is helpful to know is the actual amount of air in the tank when full. An AL 80 acutually only has 77.4 cubic feet of air.


I covered that too... :smiley20:

Phil

cgvmer
08-27-2007, 07:45
If you want charts here is one for steel.

http://diveriteexpress.com/gas/steel.shtml

Jamesmb
08-27-2007, 08:39
If you want charts here is one for steel.

http://diveriteexpress.com/gas/steel.shtml

Ok thanks, that was the little chart I was looking for. And thanks for the forumla skdvr now I can convert over what I need.

James

skdvr
08-27-2007, 10:35
OK, Larry hooked it up so that we can now upload Excel Documents so here is my chart that I made. You can add your own tank sizes into it as you see fit and the volume will change for each specific pressure.

Phil

finflippers
08-27-2007, 15:06
I made a calculator for anyone to quickly and easily figure out the remaining air supply of their tanks. For anyone interested it is at:

http://www.finflippers.com/air.html

No Misses
08-27-2007, 15:53
Thanks for the excel spreedsheets. But, I still prefer to do the math in my head. It is a good way to see how narc'ed you are. If the answer comes out to be more than the tank can hold...you are narc'ed ;-)

Sorry, the little devil on my left shoulder was choking the sh!t out of the angel on my right.

Jamesmb
08-27-2007, 18:17
Thanks for creating the calculator Brent. We diving this week?


I made a calculator for anyone to quickly and easily figure out the remaining air supply of their tanks. For anyone interested it is at:

http://www.finflippers.com/air.html

finflippers
08-27-2007, 18:37
Thanks for creating the calculator Brent. We diving this week?



I will know more after tomorrow on what days I have free this week.

skdvr
08-27-2007, 19:30
Thanks for the excel spreedsheets. But, I still prefer to do the math in my head. It is a good way to see how narc'ed you are. If the answer comes out to be more than the tank can hold...you are narc'ed ;-)

Sorry, the little devil on my left shoulder was choking the sh!t out of the angel on my right.

I would always think I was narc'd because I could not do that in my head...

Phil