# Air consumption rate

1. Feb 28, 2013

### WillemBouwer

Hi all

I am trying to set up a report showing the air consumption rate of my cylinder actuators on different valves. I am stuck at the very end where I should calculate the air consumption rate. All calcs are in metric units.

Okay as an example lets use the following:
Valve: SKG200 with closing thrust 1259kg at 10bar line pressure.
Actuator size: D = 250 mm
Valve stroke: S = 296 mm
Cylinder rod diameter: d = 32 mm
Available air pressure: P2_guage = 4 bar

Now I calculated the total cylinder volume for the closing and opening strokes:
V_open = ((D-d)/10)^2*∏/4*S = 8584.8 cm^3
V_close = (D/10)^2*∏/4*S = 11290.1 cm^3

So the total air consumption respectively:
Air_open = V_open*(P2_guage+1)/1000 = 42.92 liter
Air_closed = V_close*(P2_guage+1)/1000 = 56.5 liter

And with a maximum operating speed of 25mm/s we calculate that the duration of the stroke is:
t = S/25 = 296/25 = 11.84 sec

So now that I have all this info, how do I calculate the rate of air consumption if I want to know what size compressor to buy... Thanks guys and I hope this is in the correct forum...