Piston, screw and sliding vane compressors are all positive displacement machines, but their mechanisms give them very different operating characteristics.
Piston Compressors
A piston compresses air in a cylinder. They are efficient at high pressure but run hot and are best for intermittent duty in workshops.
Rotary Screw Compressors
Two meshed rotors compress air continuously. Screw machines are the workhorse for continuous industrial air with 100% duty cycle.
Sliding Vane Compressors
A rotor with sliding vanes compresses air in a chamber. They are simple and quiet, suited to medium-duty applications.
Choosing Between Them
- Intermittent high pressure: piston
- Continuous plant air: screw
- Moderate duty, low noise: vane