Centrifugal fan Negative pressure fan is a device that uses air convection and negative pressure ventilation to achieve forced cooling. It is mainly used in large places such as factories. However, in the process of using a negative pressure fan, various situations can occur, so let's talk about the reasons for the imbalance of the negative pressure fan impeller.

Generally, the impeller of the negative pressure fan of the centrifugal fan can be divided into two reasons for unbalanced use: the wear of the impeller and the fouling of the impeller. These two cases are related to the dust removal device connected in front of the induced draft fan. Dry dust collectors cause impeller imbalance due to wear, while wet dust collectors affect impeller imbalance due to scaling.

If this continues, vane-like wear develops at the vane outlet. For the wear of the impeller caused by dry dust removal, in addition to improving the dust removal effect of the dust collector, the method is to improve the impeller. As a result, the operating cost of the negative pressure fan and the entire production system is reduced, and the overall benefit is very good.

The synergy between these scales and the impeller surface is not uniform. Some oxide scales will automatically fall off under the action of vibration or centrifugal force, which is also the reason for the imbalance of the impeller. A practical solution is thermal spray technology, which uses a means of converting a metal or ceramic into a high-temperature, high-velocity stream of particles that is sprayed on the surface of the impeller blades, creating a material higher than the impeller itself. Floor. With high performance, and coating.

The flue gas purified by the wet dust removal device has high humidity, less uncleaned dust particles, but high viscosity. When the ash in the part falls off under the combined action of centrifugal force and vibration, the balance of the impeller of the centrifugal fan will be destroyed, and the entire induced draft fan will vibrate. Although this will increase the manufacturing or maintenance cost of the impeller, it will extend the service life of the impeller by 2 times and prolong the maintenance period of the induced draft fan. For impellers that are not thermally sprayed in service, thermal spraying of the impeller may be considered during equipment maintenance.

The dry dust removal device can remove most of the large dust in the flue gas, but a few large particles and many fine dust particles will pass through the induced draft fan through the high-temperature and high-speed flue gas, so that the blades are continuously washed. When selecting an induced extractor fan, a thermally sprayed impeller should be preferred to remove dry dust. Since this wear is irregular, it can cause the impeller to be unbalanced. This not only reduces the damage to the dynamic balance of the impeller due to wear, but also reduces the imbalance caused by the oxide layer. When they pass through the induced draft fan, they will be adsorbed on the non-working surface of the blade under the action of the gas, especially at the inlet and outlet of the non-working surface, a