Principle construction, advantages and disadvantages of scroll refrigeration compressor

Update:17 Jun 2020

Principle:The scroll lines of the moving disk and the s […]

The scroll lines of the moving disk and the static disk are the same, but the phase difference is 180 ° to mesh, forming a series of closed spaces; the static disk does not move, the moving disk is around the center of the fixed disk, and the eccentricity is taken as the radius for revolution. When the moving disk rotates around, it is engaged in turn, so that the crescent shaped area is continuously compressed and reduced, so that the gas is continuously compressed and transported, and finally discharged from the central hole of the static disk.
Moving disk (scroll rotor), stationary disk (scroll stator), bracket, cross coupling ring, back pressure chamber, eccentric shaft.

Advantages of scroll compressor:
1. The eccentric shaft which drives the moving disk can rotate at high speed, and the volume of the scroll compressor is small and the weight is light;
2. The mechanical changes of the moving parts such as the rotating disk and the main shaft are small, and the vibration of the whole machine is small;
3. It is suitable for variable speed movement and variable frequency speed regulation technology;
4. The noise of scroll compressor is very low;
5. The scroll compressor has reliable and effective sealing performance. Its refrigeration coefficient does not decrease with the increase of operation time, but slightly increases;
6. The scroll compressor has good performance. In the heat pump air conditioning system, especially in the performance of high heating, good stability, high security;
7. The scroll compressor has no clearance volume and can maintain high volume efficiency;
8. Small torque change, high balance, small vibration, stable operation, easy operation and automation;
9. There are few moving parts, no reciprocating mechanism, simple structure, small volume, light weight, few parts, high reliability, and the service life is more than 20 years.

Disadvantages of scroll compressor:
1. The surface of moving parts is mostly in curved shape, and the machining and inspection of these curved surfaces are more complex. Manufacturing requires high-precision machining equipment and precise centering assembly technology, so the manufacturing cost is higher.
2. Between moving parts or between moving parts and fixed parts, a certain movement gap is often maintained to achieve sealing. Gas leakage is bound to occur through the gap, which limits the rotary compressor to achieve a larger compression ratio. Therefore, most rotary compressors are used under air conditioning conditions.