Centrifugal Fan Arrangements
Industry standards that define how the motor mounts to & drives the fan.
AirPro // Features
Centrifugal Fan Arrangements
Centrifugal fan arrangements are standardized configurations that define how the motor is mounted and how it drives the fan. Based on Air Movement and Control Association (AMCA) standards, arrangements help specify key details like the drive method, bearing location, and overall layout, so performance and serviceability are clear from the start.
Most arrangements fall into two main categories: belt-drive and direct-drive. Within each category, there are several common options, and the right choice depends on your application requirements, operating conditions, and maintenance preferences..
AirPro Fan Arrangements Types
Belt-Drive Fan Arrangements
The motor shaft drives the fan shaft through sheaves/pulleys and v-belts. Belt-driven fans provide speed and flexibility because they enable the fan operating speed to differ from the motor’s synchronous speed. There is a power transmission loss associated with belt-driven fans that should be considered when selecting the motor horsepower.
Arrangement 3
Involves a bearing on either side of the fan wheel, supported by separate pedestals or a support structure integrated with the fan housing
Arrangement 9
The motor mounts to the side of the fan pedestal with no unitary base required.
Direct-Drive Fan Arrangements
The fan operates at the synchronous speed of the motor, as the motor drives the fan directly, either with the fan wheel mounted on the motor shaft or with the fan shaft directly coupled to the motor shaft. Direct-driven fans experience negligible power transmission losses.
Arrangement 3
Involves a bearing on either side of the fan wheel, supported by separate pedestals or a support structure integrated with the fan housing.
Arrangement 4V Top Mount
The wheel also mounts to the motor shaft, but in a vertical position.
Arrangement 7
Involves a bearing on either side of the fan wheel and supported by the fan housing.
Arrangement 8
The fan shaft couples directly to the motor shaft with a flexible coupling.
Resources
Industrial Fans: Belt-Drive or Direct-Drive?
Learn more about how to choose between belt-drive and direct-drive fans.
Scrubbers
Scrubbers commonly require fans to handle caustic materials. These fans are frequently built with 316 Stainless Steel materials and other alloy options.
Corrosive Gases
These are common in applications for biomedical, pharmaceutical, fume exhaust, and many other industries. Depending on the corrosive properties of the gas stream, the industrial fan can be built with an epoxy-coated carbon steel, stainless steel, titanium, or a nickel alloy.
Centrifugal Fan Arrangements
Centrifugal fan arrangements are standardized configurations that define how the motor is mounted and how it drives the fan. Based on Air Movement and Control Association (AMCA) standards, arrangements help specify key details like the drive method, bearing location, and overall layout, so performance and serviceability are clear from the start.
Most arrangements fall into two main categories: belt-drive and direct-drive. Within each category, there are several common options, and the right choice depends on your application requirements, operating conditions, and maintenance preferences..
Additional Resources
Learn more about how to choose between belt-drive and direct-drive fans on our blog:
Industrial Fans: Belt-Drive or Direct-Drive?
