Choosing the Right Compressor

The correct choice of compressor technology to match the duty is vital to ensure minimum cost, maximum performance compressed air generation.

The diagram below shows graphically the general selection criteria between compressor technologies.

Choosing the right compressor

 

Compressor Efficiencies and Sizes

Type

Range, cfm

Specific Power Consumption, kW/100cfm

Part Load Efficiency

Lubricated Piston

2-25

24-26

Good

25-250

18-22

Good

250-2500

16-19

Excellent

Oil-Injected Screw

2-25

24-26

Poor

25-250

18-22

Fair

250-2500

17-19

Fair*

Oil-Free Screw

25-250

20-25

Good

250-2500

16-20

Good

Centrifugal

500-2500

18-22

Excellent**

>2500

16-18

Excellent**

*Excellent with variable speed drive

**Within turndown range
Configuration Implications on Compressor Efficency 
Piston Rotary vane and screw Centrifugal General
Number of Stages
Lubricated or oil free
Number of Stages
Lubricated or oil free
 Number of Stages
Sizing
Control
Generation pressure
Cooling