Centrifugal Blower

Centrifugal blowers, also called centrifugal fans or turbine blowers, use a rapidly spinning impeller to fling air outward at high velocity. As air is thrown outward, a low-pressure zone is created at the center of the impeller, which draws in more air from the vacuum inlet. This continuous cycle creates the airflow and suction used for excavation.

Centrifugal blowers excel at producing very high airflow volumes, often 5,000 to 7,000 CFM or more, which makes them effective at moving large quantities of loose, dry material quickly. They are commonly used on air excavation trucks and combination units where high airflow is prioritized over maximum vacuum depth. Some centrifugal blowers can produce up to 16 inches of mercury vacuum.

The main limitation of centrifugal blowers is that their performance drops off significantly as restriction increases. As the vacuum hose becomes partially blocked or the dig depth increases, the blower's airflow and suction decrease. This makes centrifugal blowers less effective for deep dig and remote dig applications compared to positive displacement blowers, which maintain performance under restriction.