Ribs are reinforcing structures provided to increase the strength of the mounting-hole
section (flange) of the frame.
- Ribbed fans are intended for mounting using through-bolts that pass through both flanges.
- Non-ribbed fans are intended for applications where only one flange is secured.
* Note: Aluminum-frame fans are available only in the non-ribbed type.
Since aluminum frames have sufficient strength, they can be used with either
one-flange mounting or through-bolt mounting that secures both flanges.
Precautions:
-
Do not use through-bolts to secure both flanges of a non-ribbed plastic-frame fan. Doing so may damage the flanges.
-
When securing the fan with screws, observe the recommended tightening torque. Excessive tightening torque may cause deformation or damage to the fan.
For details, please refer to " Operating Precautions for Fan" in the Technical Material.