Pressure is a plant-wide decision
A compressed air header has one pressure. If one machine needs 13 bar and everything else runs happily at 7, the whole plant ends up at 13 bar unless the high pressure duty is separated. That is an expensive way to solve a local problem: every cubic metre delivered at a higher pressure costs more energy, and leaks lose more air the higher the pressure they leak at.
The common bands
| Band | Typical use |
|---|---|
| 7 to 8 bar | General workshop air, cylinders, hand tools, most packing equipment |
| 10 bar | Higher force actuators, some printing and textile equipment, longer lines with pressure drop |
| 13 bar | Specialised processes that genuinely need it |
| 16 bar and above | Laser cutting assist air, bottle blowing and other high pressure duties - usually on a separate header or a dedicated machine |
The two mistakes
The first is setting the header to the highest consumer's requirement and running everything from it. The second is sizing for the compressor's maximum rather than the process requirement, so the machine runs at 10 bar to deliver 7 bar at the tool because nobody accounted for pressure drop. Line losses, filters and dryers all take pressure, and an undersized line can lose a bar or more over a long run.
How to decide
- Measure at the tool - the pressure that matters is at the point of use, not at the compressor outlet.
- Add up the drops - dryer, filters, pipe run and fittings each cost pressure; size the header for the total.
- Separate high pressure duties - a dedicated machine and header for the 16 bar consumer is usually cheaper than raising the plant.
- Do not size for the occasional peak - storage handles short peaks better than a permanently higher header pressure.
What this means for machine selection
Standard screw compressors are built across the 2 to 10 bar band, with 12, 16, 20 and 30 bar variants available for duties that need them. Choosing the machine and the header together, rather than adding pressure to compensate for a layout problem, is what keeps the energy bill predictable.
Send us your working pressure, required flow and site conditions and we will propose a configuration. Contact OPPAIR.