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4. Operating principles
4. Operating principles
4.1 Screw unit
4.2 Air compressing process
Rotors
In a screw compressor the air is compressed in the air end driven by a motor.
The meshing rotors take air in between the ridges as they pass the inlet opening. When the rotors turn, the
connection to the inlet opening closes and the space between the ridges starts to decrease. At the end of
the compression phase, the desired pressure has been reached and the connection to the receiver opens.
The air in the air end is cooled by oil that is injected into it. The oil cools also the air end. In addition, the oil
lubricates the bearings and seals the clearances between the rotors and the rotor housing.
Main components of the screw
unit
1. Housing
2. Female rotor
3. Male rotor
4. Discharge flange
5. Shaft seal
6. Bearing cover
Screw unit
