The oil-injected screw air compressor is a type of double-shaft positive displacement rotary compressor. The intake port is located at the upper end of the casing, and the exhaust port is located at the lower part. Two high-precision main and auxiliary rotors are installed in parallel inside the casing. The main rotor has five lobes, and the auxiliary rotor has six lobes; their lobes are helically shaped, and they mesh with each other. The auxiliary rotor can be directly driven by the main rotor without the need for high-precision synchronous gears. Both ends of the main and auxiliary rotors are supported and positioned by bearings, and some models are equipped with a speed-increasing gear mechanism to meet specific user requirements.

The main structure diagram of the twin-screw air compressor with a speed-increasing gear mechanism

1 – Gearbox Bearing Seat; 2 – Main Gear of the Speed-Increasing Gearbox; 3 – Bearing Seat; 4 – Auxiliary Rotor; 5 – Casing; 6 – Outlet End Cover; 7 – Shaft Seal Assembly; 8 – Adjustment Shim; 9 – Bearings; 10 – Single Bearing Cap.

The main structure diagram of the twin-screw air compressor with a speed-increasing gear mechanism

1 – Main Rotor; 2 – Bearing Locating Ring; 3 – Bearing Seat; 4 – Auxiliary Rotor; 5 – Casing; 6 – Outlet End Cover; 7 – Shaft Seal Assembly; 8 – Adjustment Shim; 9 – Bearings; 10 – Bearing Cap and Locating Ring; 11 – Butterfly Gasket.