Air Compressors

Air Compressor Selection — Quick Reference

Air compressor sizing turns on: (1) CFM/LPM demand of your tools, (2) operating pressure (7-13 bar typical AU workshop), (3) duty cycle (intermittent vs continuous). Undersized compressor = tool starvation; oversized = wasted capital + power.

Sizing rule: Total CFM demand of simultaneous tool use × 1.25 safety factor = required compressor CFM at operating pressure. AU standard pressure 90 PSI (6 bar) tool side; compressor 8-13 bar with regulator. Critical: Belt-drive compressors with cast-iron pumps last decades; direct-drive light-duty pumps last years. Match compressor class to duty cycle. Air prep mandatory: use FRL set after receiver (Filter + Regulator + Lubricator) — see FRL components. Companion: pneumatics, air guns, pneumatic fittings, air compressor guide.

Air compressors convert electrical or engine power into pressurised air for running pneumatic tools, spray equipment, blow guns, tyre inflation and a long list of plant and workshop tasks. The right unit depends on the air flow your tools need (measured in litres per minute or CFM), the pressure they need to operate (typically 7–13 bar in Australian workshops), and how continuously you run them.

What to look for

• Air flow (LPM or CFM) — add up the consumption of every tool you might run at once, then add 25–30% headroom.
• Tank size — bigger tanks reduce duty cycle and let pulse-loading tools (impact wrenches, sandblasters) run cleanly.
• Single-stage vs two-stage — two-stage compressors deliver higher pressure (10 bar+) and run cooler under load. Better for production environments.
• Oil-injected vs oil-free — oil-free units suit medical, food and dental applications. Oil-injected last longer under heavy industrial duty.

Need help spec'ing the right compressor for your workshop? Get in touch — we'll size it properly the first time.

Companion ranges: Pneumatics · Air Compressor Guide

People Also Ask — Air Compressors

Q: Why do cast-iron pump compressors outlast light-duty units under sustained workshop use?

Belt-drive compressors with cast-iron pumps last decades, while direct-drive light-duty pumps last years — match the compressor class to the duty cycle rather than choosing on price alone.

Q: Why would a workshop choose an oil-free compressor over an oil-injected one?

Oil-free compressors suit paint, food and medical applications needing clean, dry air, while oil-injected compressors last longer under heavy industrial duty — the choice depends on whether air purity or long-term durability matters more for the application.

Q: When would a petrol or diesel-engine portable compressor be the right choice over an electric one?

For site work with no mains power available — petrol-engine portables suit general site work, while diesel-engine portables suit heavier site duty and sustained outdoor use.

Q: Why does air receiver (tank) size matter for tools like impact wrenches or sandblasters?

Bigger tanks reduce duty cycle and let pulse-loading tools such as impact wrenches and sandblasters run cleanly, drawing from stored air rather than directly taxing the compressor pump on every pulse.

Q: Single-stage or two-stage belt-drive compressor for a production environment?

Two-stage compressors deliver higher pressure (10 bar and above) and run cooler under load, making them the better choice for production environments; single-stage belt-drive units suit light commercial and sustained workshop use rather than continuous production.