In the initial stage of impeller operation and all regular inspections of the blower, whenever there is an opportunity, the blower impeller should be inspected for cracks, wear, dust accumulation and other defects.
Keep the blower impeller as clean as possible, and regularly wipe the dust and rust on it with a wire. Because it cannot be evenly attached to the impeller with the extension of the running time, the balance of the impeller will be broken, causing the rotor to vibrate.
The blower impeller should be rebalanced whenever repaired. If available, you can balance on-site using a portable exam balancer. Make sure all mounting bolts are tightened before dynamic balancing. The impeller has been running out of balance for some time, so these bolts may have come loose.