Over our years designing, developing and delivering custom centrifugal fans and blowers for industrial applications, we have learned that no detail is too small in the specification process. This holds true when we talk about motor bearings too. There’s a specific nuance to consider when selecting motors for high horsepower belt-driven fans.
How do you determine the right motor speed for your industrial centrifugal fan? You’ll need to consider your fan’s drive arrangement and one more factor that frequently gets missed: frequency of the motor’s input power.
The key indicator for determining fan motor size is fan brake horsepower (BHP), which represents the force needed to brake, or stop, the motor. This is the minimum amount of power needed to operate the fan.
The Arrangement 7 fan is center-hung with the impeller mounted between two bearings and an integral inlet box to direct the air into the fan from above or from the side. This fan arrangement is optimal for use when your application requires large fan impellers and/or when you want to go the extra mile for increased fan life.
Fan arrangements define the way a motor drives the fan, and how the motor mounts to the fan, based on AMCA standards. The Arrangement 7 Fan offers a maintenance-friendly and reliable design for fans with larger impellers, as the impeller is center-hung between two bearings. The entire fan assembly is assembled on a common base and can be either belt or direct drive.
Fan arrangements define the way a motor drives the fan, and how the motor mounts to the fan, based on AMCA standards. They can also be application-specific, as with the Arrangement 4V Top Mount Fan.
When designing and installing your industrial fan, it is essential to consider the full system and long term needs, including surrounding ductwork and fan maintenance.
Centrifugal fans, with their moving parts and sometimes heavy-duty air processing, require regular fan maintenance in industrial applications. You might need to clean it, you might need to balance it, you might need to repair a part, or even retrofit the fan. At some point, you’ll need access to work on the wheel and shaft. If you’re not sure you’ll be able to get into the access doors in your application, split housings might just save the day.
Insulation surrounding industrial centrifugal fans serves dual purposes of thermal and sound protection. It also creates a sheath around the fan, requiring some accommodation for access when maintenance or repairs are needed. There are multiple fan insulation types to accommodate different applications.
Industrial fans have a special job to do when used in a dust collection application. They need to get the dust-laden air past the filters in the dust collector baghouse. The system pressure varies based on how “dirty” the filters are, and you can adjust the fan speed accordingly. Properly adjusting the speed can reduce your overall power consumption, but that depends on whether or not you place the pressure gauge in the right spot.
