What is Draftguard®?

Draftguard® is an anti-rotation device typically used to stop ACHE fans from rotating backwards.    Reverse rotation can strain the motor system during start up and pose a safety hazard to maintenance workers; eliminating reverse rotation can improve safety and reduce maintenance.  

While Draftguard has typically been applied to ACHE fans,  it can be used in other applications to limit rotation to a single direction.  Draftguard can be mounted to the following bushings:

• 3020, 3525, 3535, and 4030 (TL style)
• E, F, and J (QD style)

A locking ring is also available to mount Draftguard in cases where it can not be mounted directly to the bushing.

 Learn more about Gates' Draftguard anti-rotation solution at www.gates.com/draftguard/. 

Power and Fan Speed for Belt Drive Conversions

The power required to drive a fan relates to the fan shaft speed as follows:

Initial_Horsepower/New_Horsepower = (Initial_Fan_RPM/New_Fan_RPM)^3

A small speed change can result in a substantial increase in power consumption. Therefore, this relationship should be considered when replacing a V-belt drive with a synchronous belt drive for energy savings.

To ensure that the fan speed does not increase, the design speed ratio should be based on a measured fan shaft RPM of the existing V-belt drive. This measurement can be made with a contact or a strobe tachometer.