Workshop Compressor Requirement Table
| Machine | Air Consumption | Pressure | Recommended Compressor |
|---|---|---|---|
| EasyBlast sandblasting (10 L) | 300 L/min | 5-6 bar | 5.5-7.5 kW screw + 200 L receiver |
| FastBlast sandblasting (25 L) | 500 L/min | 6-8 bar | 7.5-11 kW screw + 300-500 L receiver |
| CNC bridge saw | 100-200 L/min | 6-7 bar | 4-7.5 kW + 200 L receiver (can be shared) |
| 5-axis waterjet | 50-100 L/min | 6-8 bar | 3-5.5 kW + 200 L receiver |
| Polishing equipment | 100-300 L/min | 6 bar | 7.5 kW screw |
| Pneumatic hand tools (general) | 50-150 L/min | 6-8 bar | 3-5.5 kW + 100 L |
Working Out the Total
When selecting a compressor, add up the consumption of every machine and allow a further 20-30% as reserve. In a workshop running two shifts a standby compressor (n+1 redundancy) is recommended.
Piston Versus Screw Compressors
Piston (Reciprocating)
- Lower capital outlay
- Suited to intermittent use (start/stop)
- Poor for continuous running (temperature and service life)
- High vibration and noise
- Consumes oil (lubricated types)
- Frequent maintenance (cylinder, valves, piston rings)
- Medium air quality (oil contamination is possible)
- Typical service life: 5-8 years
Screw
- Higher capital outlay (initial cost)
- Ideal for continuous running
- Low vibration and quiet
- Minimal oil consumption (a closed system)
- Little maintenance (an annual service)
- High air quality (oil-free versions are available)
- Typical service life: 10-15 years
- The standard for a modern workshop
For an industrial workshop a screw compressor is all but mandatory — a piston machine is only suitable for a small shop or a car repair bay.
Receiver Size — How Much Do You Need?
The receiver absorbs pressure fluctuations and stops the compressor from starting and stopping continuously.
- The rule: air consumption (L/min) × 1-1.5 = receiver size (L)
- Example: 500 L/min consumption → a 500-750 L receiver is ideal
- Too small a receiver → the compressor cycles on and off constantly (shortening its life)
- Too large a receiver → it takes up floor space for no return
- The industrial standard: a minimum of 200 L (a small workshop), 500-1,000 L (medium to large)
Air Quality — the Filtration Stages
Compressed air in its raw state can be moist, oily and full of particles. Four stages of treatment before it is put to use are standard:
- WATER SEPARATOR (cyclone separator) — collects bulk water, drained annually
- DRYER (refrigerated or adsorption) — brings the dew point down to 3°C
- OIL FILTER (coalescing filter) — separates 0.01 µm particles and oil vapour
- PARTICLE FILTER (final) — 0.01 µm rating (critical for CNC and paint lines)
What Unfiltered Air Leads To
Unfiltered moist air → rust inside the machine and sticking valves. Oily air → paint contamination and blocked blast guns. A filtration system accounts for a 95% difference in workshop efficiency.
Oil-Free Versus Lubricated Compressors
- Lubricated screw — the standard, more economical; air treatment plus an oil filter is essential
- Oil-free — for food, pharmaceutical and electronics work; 30-40% more investment
- For a paint line → oil-free is preferred (zero contamination)
- For sandblasting → lubricated is enough (provided it is filtered)
- For CNC → lubricated is enough
- For waterjet → lubricated is enough
Installation Recommendations
- A ventilated enclosed room — temperature between 5 and 40°C (no freezing, no excessive heat)
- A separate compressor room → the noise does not carry into the workshop (a screw machine runs at 70-75 dB)
- The air intake must be clean — not near dust, exhaust fumes or chemical vapour
- Drainage — a floor gradient for water discharge
- Electrical supply — three-phase, with balanced phases (15-30 kVA)
- Service access — 80 cm of clearance on all four sides
Maintenance Schedule
| Task | Frequency | Responsibility |
|---|---|---|
| Water draining (automatic) | Daily (automatic) | Automatic valve |
| Cleaning the air filter | Monthly | Operator |
| Checking the oil level | Weekly | Operator |
| Oil change | 4,000-8,000 hours | Authorised service |
| Oil filter | 4,000 hours | Authorised service |
| Air filter (compressor intake) | 2,000 hours | Authorised service |
| Belt check / replacement | Annually | Authorised service |
| Screw element overhaul | 40,000+ hours | Authorised service (a major overhaul) |
| Receiver pressure test | Annually (a legal requirement in Türkiye) | Accredited test body |
How to Approach the Investment
- The compressor, the receiver and the filtration system should be assessed as one whole
- A standby compressor (n+1) — mandatory where production is critical
- A variable-speed (inverter) model — 30% energy saving under a varying load
- A heat recovery system — the waste heat can be used to warm the workshop
- The net investment varies with capacity and with the make you prefer; ask your supplier for a quotation