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Unread 17-02-2004, 16:26
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Re: Volume of tank + tube

Quote:
Originally Posted by Kevin Sevcik
P1*V1=P2*V2. And I'm ignoring the volume of the tubes, as it is relatively negligible at this scale.
The equation is right, but you forgot the accumulators are at 120psi. I'm also not sure about your volume calculations. I thought the accumulators are 2" bore x 6" long, which gives 18.8 in^3. I could be wrong, but the answer won't be terribly different if they are 16 in^3

You use 14.1 in^3 (at 60 PSI) when you actuate the cylinder. The accumulators hold 37.6 in^3 (at 120 PSI). Since you are only using the air at 60 PSI, you effectively have 75.2 in^3 of air, and when you get down to 37.6 in^3, you will only have 60 PSI. Thus, you have 37.6 in^3 of air to work and can actuate the cylinder twice. If you can regulate the cylinder to 50 PSI, you could get 3 shots.