Industrial fans are machines designed to produce a large flow of air or gas. Used in a wide range of industries and for various applications, these fans have blades connected to a hub and shaft and driven by a motor that rotates. The two primary types of industrial fans are axial and centrifugal. Within these categories are many different sub-types, each with unique benefits and features.
Axial Industrial Fans
Axial fans use axial force to move air or gas. The design includes a central hub that spins and blades that extend from the outside diameter. Parallel to the wheel’s shaft or axis of rotation fluid is moved. Typically, the fan wheel is contained inside a small section of the cylindrical ductwork where inlet and outlet ducting can be connected.
The diameter of the wheels for these industrial fans is usually less than one foot and more than 30 feet but sometimes, the diameter can be greater than 41 feet. When the main goal is to produce a large volume of air or gas flow and when flow and higher pressures are needed, axial industrial fans work best.
Centrifugal Industrial Fans
For centrifugal industrial fans, force is generated with a disk that rotates and blades that are mounted to the disk at right angles. This produces air or gas movement and increases pressure. The fan wheel, which consists of the hub, disk, and blades, usually includes a number of additional structural and aerodynamic functions.
In most cases, the fan wheel is contained in a housing shaped like a scroll. When in operation, air or gas within the spinning fan is shot outside the wheel to an outlet at the largest diameter of the housing. At the same time, more air or gas is drawn in through the central hole into the wheel. Usually, inlet and outlet ducting are attached to the housing in order to supply and/or exhaust the air or gas but this depends on requirements specific to the industry.
Just as with axial fans, there are many different types of centrifugal industrial fans. These fans have wheels that are less than one foot to those that stretch more than 16 feet in diameter.