The storage volume for a compressed gas can be calculated by using Boyle's Law
p a V a = p c V c = constant (1)
p a = atmospheric pressure (14.7 psia, 101.325 kPa )
V a = volume of the gas at atmospheric pressure (cubic feet, m 3 )
p c = pressure after compression (psi, kPa )
V c = volume of gas after compression (cubic feet, m 3 )
Volume of free gas in a Storage Volume
The amount of free gas at atmospheric pressure in a given volume - like a cylinder storage - can be calculated my modifying (1)
V a = p c V c / p a (2)
Gas can be stored in high-pressure cylinders ranging to more than 6000 psig (410 bar) . Normal-pressure cylinders are in the range 2000 and 2500 psig (140 and 175 bar) and low-pressure cylinders are in the range 480 psig (34 bar).
Example - Volume of Air in a Cylinder Storage
Standard atmospheric volume of air compressed in a 1.76 cubic feet K-type cylinder at 2200 psig (2214.7 psia) can be calculated
V a = (2214.7 psia) (1.76 cu ft) / (14.7 psia)
= 265 (cu ft)
In other words - if air in a 1.76 cubic feet container is compressed to 2200 psig - the same air at atmospheric pressure will occupy 265 cubic feet .
Air, LNG, LPG and other common gas properties, pipeline capacities, sizing of relief valves.
Compressed air is used for power tools, instrumentation, processing, breathing and medical purposes.
Calculating air receivers capacity.
The ratio of compressed air pressure to free air pressure.
Common rating terms for air flow capacity are ICFM, FAD, ANR, SCFM or nl/min.
Reciprocating, rotary screw and rotary centrifugal air compressors.