Why Industrial Fans Matter
The purpose of an industrial fan is to provide a large flow of air or gas to various processes. This is usually directed through a rotation of blades which are connected to a hub/shaft, and driven by a motor.
Industrial Fan Basics
There are numerous uses for the continuous flow of air or gas that industrial fans generate, including: combustion, ventilation, exhaust, and particulate transport to name a few. Fans operate in both clockwise and counterclockwise orientations, and common accessories for fans include: flanges, shaft seals, belts, and bearing guards. Belt/shafts and bearing guards are extremely important as OSHA requires it – they are an absolute must!
The Two Primary Types of Industrial Fans
Centrifugal fans utilize what’s known as a “centrifugal force” generated by a rotating disk, with blades mounted at the right angles to the disk, to impart movement to the air or gas stream and increase its pressure. In contrast to axial fans, centrifugal fans/blowers use wheels rather than propellers. The centrifugal fan wheel is typically contained within a scroll-shaped fan housing. The air or gas inside the spinning fan is thrown off the outside of the wheel to an outlet at the housings’ largest diameter. There are a variety of centrifugal fans, which may have fan wheels that range from less than a foot to over 16 feet.
An axial fan design utilizes axial forces to achieve the movement of the air or gas, spinning a central hub with blades extending radially from its outer diameter. Unlike the centrifugal fan, axial fans utilize propellers rather than wheels. The axial fan is often contained within a short section of cylindrical ductwork, to which inlet and outlet ducting can be connected. Axial fan types have fan propellers with diameters that usually range from less than a foot to over 30ft. Simply put, axial fans are used where the principal requirement is for a large volume of flow, and the centrifugal design where both flow and higher pressures are required.
There are numerous subset designs within each of these groups to meet the specific needs of your process (backward-inclined, shrouded radial, paddle wheel, air foil, tube axial, etc…).