Air demand largely depends upon the air consumption and use. The varying air consumption pattern is called as ‘Demand cycle’.
In rare cases the air demand is steady and consistent (e.g. in air separation plant, textile spinning, etc…). Whereas the air demand fluctuates in almost all other applications.
To calculate the total compressed air demand while designing a new manufacturing facility, the air demand of each machine is assessed individually and then computed to arrive at the total air demand. Air consumption of each pneumatic equipment and duration (for how long it is working in hours and how often in days), assessment of leakages, and air pressure are considered.
Whereas in a normal operating plant, data logging of flow and pressure on the consumption side provides
One of the challenges with compressed air system design is dealing with periodic large flow demands.
Managing high intermittent demand cycles / events requires evaluation of multiple aspects of your system:
1) Air compressor controls.
2) System master controls.
3) Piping and air velocity.
4) Storage: wet, dry, and at points of use.
5) Identifying and examining large air users.
6) Designing with flexibility and the future in mind.
(See also, ‘Demand pattern’)