The difference between the compression principle of scroll and screw compressor

There are significant differences in the compression principles of scroll compressors and screw compressors. Here are the main differences between the two:

compression principle of 1. scroll compressor

structure: The scroll compressor is mainly composed of a movable scroll (movable disk) and a fixed scroll (static disk).

Working principle: the vortex shape of the dynamic and static scroll is basically the same, the phase difference is 180 °, and there is a certain eccentricity. Four compression chambers are formed between the 2 vortices, each of which is crescent-shaped. During the compression process, the scroll stator (static disk) remains fixed, and the scroll rotor (movable disk) moves clockwise every 90 degrees. With the rotation of the moving disk, the gas is gradually compressed in a number of crescent-shaped compression chambers composed of static and dynamic disk, and then continuously discharged from the axial hole in the center of the static disk.

Compression principle of 2. screw compressor

structure: The screw compressor mainly relies on a pair of intermeshing male and female rotors (screws) to work.

Working principle: When the rotor groove passes through the suction port, it is filled with gas. As the rotor rotates, its recess is closed by the housing wall, forming a compression chamber. When the rotor grooves are closed, lubricating oil is injected into the compression chamber, which can provide both sealing and cooling and lubrication. During the rotation of the rotor, the lubricating oil and the gas are mixed, and the gas is compressed and discharged.

In summary, the main difference between scroll compressors and screw compressors lies in the structure and working mode of their compression elements. The scroll compressor compresses the gas through the relative movement of the orbiting and stationary scroll, while the screw compressor relies on the intermeshing male and female rotors to complete the compression process.