The amount of air you can put into an air tank depends on the tank's physical volume capacity and the maximum pressure it is designed to hold. Air tanks come in various sizes, and their capacity for compressed air is determined by these two factors.
Understanding Air Tank Capacity
When considering how much air an air tank can hold, it's important to distinguish between:
- Tank Volume: This is the physical space inside the tank, typically measured in gallons or cubic feet. A larger tank volume can physically hold more air (or any substance) at a given pressure.
- Gauge Pressure: This is the pressure of the air inside the tank, measured relative to atmospheric pressure, often in Pounds per Square Inch (PSI). Higher pressure means more air molecules are compressed into the same volume.
Therefore, a larger tank filled to a higher pressure will hold significantly more total compressed air than a smaller tank filled to a lower pressure.
Examples from Air Tank Capacities
Based on the information provided by New-Line Hose and Fittings, here are some examples of common air tank sizes and the typical gauge pressures they can hold:
| Tank Size (inches) | Tank Size (gallons) | Gauge Pressure on Tank (PSI) |
|---|---|---|
| 20 x 48 | 60 | 90 |
| 20 x 63 | 80 | 120 |
| 24 x 68 | 120 | 180 |
| 30 x 84 | 240 | 360 |
These examples show that air tanks range significantly in size, from 60 gallons up to 240 gallons or more, and are designed to safely contain compressed air at pressures ranging from 90 PSI to 360 PSI, or potentially higher depending on the specific tank's rating.
To determine the exact amount of air (like standard cubic feet, SCF) held in a tank, you would need to know its volume and pressure, and apply gas laws, but the table above gives you a clear idea of the physical volume and the pressure rating for various tanks.
