in rotary screw air compressors, the most important part is the screw unit. For this reason they are called as rotary screw. These type air compressors are known as the last technology.
The principle of working of screw compressors is different from the piston type compressors. In screw compressors, all system of compressor is designed to rotate airend.
When compressor start running, firstly, it raises the compressor’s inside pressure approximately 1-2 bar. Thanks to inside pressure, the oil starts moving in compressors and the airend is lubricated. After a while, the intake valve is opened automatically to suck air from atmosphere and the compressor sends air and oil to the separator tank together. In this tank, air and oil are separated from each other by separator filter. After separation, oil and air come to the radiator separately for cooling. Finally, cooled air is sent to working, and the oil goes on circulating in the compressor. Thanks to circulating oil, the temperature of compressor decreases.
Screw air compressors generally work at 7-8 bar pressure. When they reach to that pressure amount, they keep working idle without sending air for usage. There is a relay in the compressor’s electrical panel. if there is no usage of air in the system, the compressor uses this relay to stop it. If compressor working idle, the relay starts countdown from the settled time. At the end of countdown, compressor temporarily stops. Until the pressure of system decreases to a certain amount of pressure that set on the pressure switch, compressor stays at stop mode and then compressor runs again. If the system’s pressure decreases to that certain amount of pressure before compressor stops, compressor maintains running load without stopping. This principle of working of air compressor indicates that compressors do not need any operator. They run automatically.
Screw air compressors are designed as quiet by the manufacturers.
More efficient than reciprocating compressors.
Screw air compressors can reach high capacities that piston compressors cannot.
These compressors are the high technology products.
If services done completely, they are long lived.
Screw air compressors are more expensive than reciprocating air compressors.