In the initial stage of operation of the centrifugal fan impeller and during all regular inspections, as long as there is an opportunity, the impeller must be inspected for defects such as cracks, wear, and dust accumulation. As long as possible, the impeller must be kept clean, and the dust and rust on it must be brushed with a wire brush regularly because, with the extension of operating time, this dust cannot be evenly attached to the centrifugal fan impeller. As a result, the balance of the impeller of the centrifugal fan is destroyed, and the rotor vibrates. As long as the centrifugal fan impeller is repaired, it needs to be rebalanced. If conditions permit, it can be balanced on-site using a portable test balancing instrument. Before balancing, all set bolts must be checked for tightness. Because the centrifugal fan impeller has been running out of balance for some time, these bolts may have loosened.