Jiebao air compressor screw type

They are powered by two counter-rotating screws that compress air as it moves through the compressor. These units are designed for continuous use, capable of operating 24 hours a day, 7 days a week. [pdf]

Screw air compressor intake valve oil injection

When the inlet/unloader valve is open, the air enters the compressor screw element. The screw element works like a pump and it compressed the air. During this process, oil is injected in the element. The oil is there to cool the air, as the air gets very hot during compression. [pdf]