Planning a Compressed Air Installation

The first stage to planning a compressed air pipe system is working out the flow rates.

This is achieved by looking at the flow rate of your compressor or the flow required by the equipment using air. We have included tables for compressor flow rates and typical tool air usage.

The following is a guideline to work out the output of your compressor:

Power of compressor motor (KW)Approximate flow rate (cfm)
1.58
423
5.532
7.542
1162
1588
22124
55300
110636

 

Typical air tool flow rates

ToolFlow rate required approx. (cfm)
Tyre Inflator1.5
DA Orbital Sander15
HVLP Spraygun20
Air Drill5
Blow Gun4
1/2″ Impact Wrench4
1″ Impact Wrench12

 

Once you have a figure to work with compare it to our table below to work out the size of pipe you require. The column on the left shows the cfm flow rating and the row on top shows the distance from the compressor to the furthest outlet in metres. Follow the lines down and across to highlight the tube size you require.

25m50m100m200m500m1000m
8 cfm202020202020
23 cfm202020252532
32 cfm202020253232
42 cfm202025253240
62 cfm202525324040
88 cfm252532324050
124 cfm253232405050
300 cfm404050506363*
636 cfm50506363110110
1766 cfm63110110110110*110*
3531 cfm110110110110*110*110*

Measurements calculated at 7 bar – * Pressure drop is higher than 4%

 

The next step is to consider pipe runs. It is almost always better to run a circuit when designing a compressed air system. This is known as a ring system or ring main. This means any outlet or drop will have two sources of flow from either side of the tee piece. See image below:

air ring system

Further considerations include:

What will it be clipped to or hung from? Ceiling, wall.
What will be on the outlet? Regulator, gauge, quick release coupling.
Where should isolation valves be placed?
Will there be expansion in the future?

For any more advice you may require we have engineers in our office waiting to help call us on: 01480 217904.