Formulas to calculate air tank fill time

[AggieJustin]

I came across a site the other day that gave some formulas for calculating how long it takes to fill a tank of given size, based on the CFM ratings of an air compressor.



And just like usual on the web, I can't find the site when I need it. Does anyone have a link to a site or can post the formulas here? I've got that CFM ratings for the compressor at various pressures. I've calculated it by taking the average of the CFM ratings from 0 to my cutoff pressure to get a mean CFM, then used this number to calculate time to pump the number of cubic feet in my tank. But I don't think this is correct. Just looking for confirmation.



Thanks,



JM

 

[Jacobs]

I have a formula for calculating the time required to recharge a reservoir.



It is as follows:



t = {V[P1 – P2]} / {[Qout – Qin] x 14. 7}



V = Size of receiver in Cubic Feet

t = Time to charge in Minutes

P1 = Initial Working Pressure

P2 = Final Working Pressure

Q = Cubic Feet of Air Flow In or Out



As an example, if the Compressor is rated at 10 CFM and your reservoir is 10 gallons which calculates into 1. 33 cubic feet, it would take



t = {1. 33[0 – 125]} / {[0 – 10] x 14. 7}

t = [-166. 25] / [-147]

t = 1. 13 minutes



Good luck



Bruce