Centrifugal fans and blowers are made of an intake duct conveying the aspirated gas to the impeller inlet that is coaxial to the shaft.
Centrifugal fans and blowers are commonly used for extraction or compression of combustible gases, such as biological or natural gas.
The rotating parts are not in contact with the casing during rotation. There is therefore no friction during operation and thus no internal lubrication is necessary. The gas moving through the machine remains uncontaminated and completely oil-free.