Calculation of air volume and pressure for compressed air in the air compressor

The calculation of the gas volume and pressure of compressed air in the air compressor involves many aspects. The following is a clear and partial summary:

1. Determination of gas volume

1. Traditional method:
   • Add the gas volume (m³/min) of all gas-using equipment.
   • Consider adding a safety, leakage and development coefficient.
2. Test method: Perform a timed pump air test, which is a method to accurately check the gas volume or output of an existing air compressor.
   • Air tank volume (m³) + The volume of the pipeline between the compressor gas tanks (m³) = Total volume (m³).
   • The compressor is running at full load, close the specific air valve, and then close the air vent valve after deflation to a specific pressure, and record the time required for the pump air to unload pressure.
   • Use the formula C=V(P2-P1)60/(T)Pa to calculate the compressor exhaust volume, where C is the compressor exhaust volume (m³/min), V is the gas storage tank and pipeline volume (m³), P2 is the final unloading pressure (MPa), P1 is the initial pressure (MPa), Pa is the atmospheric pressure (MPa), and T is the time (s).
3. Estimation method:
   • V=V gas volume used in existing equipment + V gas volume used in post-treatment equipment + V leakage + V reserve.

2. Calculation and consideration of pressure

1. System pressure:
   • The output pressure of an air compressor in industry is usually 0.69MPa(G), and the pressure at the point of use of the equipment is at least 0.62MPa.
   • The unloading pressure of the compressor and the cylinder loading pressure (or system pressure) are key parameters.
2. Increase the air supply of compressed air:
   • Determines based on the amount of air that increases the system pressure to the required pressure.
   • M/min required = existing m³/min × (P2/P1), where P2 is the required system pressure and P1 is the existing system pressure.
3. The impact of system air leakage:
   • Insufficient gas supply is often caused by system leakage, so the leakage needs to be checked regularly and calculated.
   • Leakage amount m³/min = V(P2-P1)60/90(Pa). If the leakage rate exceeds 5% of the entire system gas volume, the leakage must be plugged.

3. Select the compressor specifications

• After determining the gas volume (m³/min) and pressure (MPa(G)) of the factory gas, you can select the appropriate air compressor specifications.
• Considerations include current and future gas usage, performance characteristics of various compressor models, and dynamicsforce cost, etc.

To sum up, the calculation of the gas volume and pressure of compressed air in an air compressor is a process that combines multiple factors and needs to be carried out in combination with actual needs and conditions.