Working pressure is a critical factor that can significantly impact energy consumption when it comes to dimensioning a compressed air installation.
The compressor along with its system design, piping, valve, dryers, filters and other ancillary equipment help determine the necessary working pressure. Different types of equipment can demand varying pressures within the same system. Normally, the application with the highest pressure determines the requisite installation pressure, and other equipment is fit with pressure reducing valves or regulators at the point of consumption.
Example for calculating working pressure
To calculate the compressor system’s working pressure, you need to know your production equipment’s air pressure requirement while taking into consideration the source, which can cause pressure drops along the way from the compressor to the production line.
Description
|
Pressure (PSI)
|
Production line requirement
|
90
|
Sources of Pressure Drop
|
Pressure (PSI)
|
Dryer
|
3
|
Coalescing Filter
|
1
|
Dust Filter
|
2
|
Piping (elbows, reducers, valves, fittings)
|
4
|
Required Compressor pressure
|
100 PSI
|
Calculating your equipment’s total air requirement
To assess your equipment’s air requirement, you can use the following table as a guide. The table breaks down individual utilization factors to determine upper and lower limits for overall air demand.
Connected equipment
|
Nominal air requirement
|
Utilization factor
|
Total air requirement average
|
Tools
|
300 CFM
|
50%
|
150 CFM
|
Production lines
|
200 CFM
|
80%
|
160 CFM
|
Process lines, total
|
|
|
310 CFM
|
In this example, we would need a compressor that could produce 310 cfm at 100 psi.
Factors to consider when determining your equipment’s air equipment and the system’s working pressure
- The air requirement for your connected equipment can be obtained from tool catalogues and production equipment data.
- Pressure drop increases as flow increases. If a change in consumption is expected, it’s economical to adapt the installation to these conditions.
- Filters have a low initial pressure drop, but this increases as filters can become clogged over time. They should be replaced at the recommended pressure drop.
- The compressor’s flow regulation causes pressure variations and should be included in the assessment.
- The end application along with the pressure drop between the compressor and the end use can determine the working pressure needed.
Understanding your system’s working pressure can help save time and money in the long run. Get expert insight into your application demands and how you can adapt your compressor installation accordingly when you leave us a comment below.
