Difference between single stage centrifugal blower and multistage centrifugal blower

Both single-stage and multi-stage centrifugal blowers are working wheels. In the process of rotation, due to the effect of rotating centrifugal force and the diffuser flow in the working wheel, the gas velocity is increased, and then the velocity energy is converted into pressure energy in the diffuser. The difference is that the single-stage centrifugal blower has only one group of impellers, and the air compression is completed at one time, while the multi-stage centrifugal blower has multiple groups of impellers on one main shaft, and the air compression is gradually completed among multiple groups of impellers.

Because the centrifugal blower depends on improving the air flow speed, that is, the air kinetic energy to compress the air and increase the pressure, in order to obtain the same pressure, the impeller of the single-stage centrifugal blower must be several times higher than the speed of the multi-stage blower. Generally, the speed of the multi-stage centrifugal blower is only several thousand revolutions, while the speed of the single-stage centrifugal blower is as high as tens of thousands or even hundreds of thousands of revolutions. Because the supply of pressure largely depends on the increase of speed, and the supply of speed is limited by balance, lubrication and material performance, so single-stage centrifugal blower is more used in low pressure situation, and multi-stage centrifugal blower is more used in high pressure condition.

The single-stage centrifugal blower generally relies on the gearbox to obtain a very high speed. Because the speed is particularly high, the control and maintenance of the blower is particularly important. It must be equipped with a separate lubricating oil station at the same time. At the same time, due to the high speed, many parts, such as blades, are greatly worn, so the service life of the single-stage centrifugal blower is more and that of the extreme centrifugal blower is lower.

  The main disadvantages of single-stage centrifugal blower (relative) are:

1. Complex mechanism, the unit has lubricating oil station, gear box and other auxiliary mechanisms and settings;

2. High speed, high noise

3, large amount of maintenance, high maintenance difficulty; Because the parts of the blower wear fast, and the balance, assembly requirements are very high;

4. The control is complex and the operation is difficult;

5. The blower is easy to vibrate.