Compressed air is the most expensive form of energy in a factory: roughly 8-10 units of electricity go into the compressor for every unit of useful work at the tool. Yet in many factories 20-30% of the air is lost through leaks.
The parts of the system
- Intake filter - clean, cool air in. A hot, dusty intake lowers efficiency.
- Compressor - usually a screw compressor in garment factories. Rated in kW and m³/min (or CFM) at a pressure, typically 7-8 bar.
- Air receiver - a tank that stores air, smooths pressure and lets water settle. Drain it daily (or use an auto drain).
- Dryer - removes moisture so water does not reach machines and garments (refrigerated dryer is common).
- Line filters - remove oil and particles.
- Ring main - a loop pipe around the floor, so pressure stays even at both ends.
- Drops with FRL units - Filter, Regulator, Lubricator at each machine; the regulator sets the pressure the tool really needs.
Who uses air on a garment floor
Auto thread trimmers and pneumatic presser-foot lifters, fusing presses, spot-cleaning guns, button and snap machines, vacuum tables in finishing and cutting, blow guns for cleaning.
The cost of leaks
A single 3 mm leak at 6-7 bar wastes about 0.7 m³ of air per minute. At about 6 kW of compressor power per m³/min, that is roughly 4 kW running all day - around 100 units of electricity per day for one small hole (check with your own compressor data).
Note: Leaks are quiet in a noisy factory. Hunt them after the shift when machines are off - listen, use soapy water, or an ultrasonic leak detector.
Saving air - a checklist
| Action | Typical effect |
|---|---|
| Fix leaks monthly (tag, repair, re-check) | Biggest single saving |
| Lower header pressure by 1 bar if tools allow | ≈ 6-7% less compressor energy |
| Switch off compressor and isolate lines after shift | Stops leak losses at night |
| Ban blow guns for cleaning people or floors | Safety and air saving |
| Take intake air from a cool, shaded place | Better efficiency |
| Use the compressor heat for hot water (heat recovery) | Free heat |
Key points
- Air is expensive energy - treat it like electricity.
- Receiver, dryer and filters protect machines and garments from water and oil.
- Leaks and over-pressure are the easiest savings.