Fan Vibration Isolation Considerations
Fans and vibration don’t get along very well! High vibration levels can shorten fan life and even cause catastrophic failure. Fan installation setup is a key factor to protect the fan from excessive vibration. Your fan should be installed on a foundation or structure designed to either handle the vibration itself or use vibration isolation devices.
Ideal Fan Foundation
Ideally, every fan would be installed on a solid concrete foundation with enough mass to withstand vibration frequencies from the fan and the surrounding environment. This foundation would extend at least six inches beyond the fan’s base perimeter and weigh 3-5 times more than the fan. However, this is not always possible.
Many applications don’t have enough space for such a foundation and many others install the fan within steel mezzanine structures. In such cases, the fan should be isolated from the surrounding environment. You will need vibration isolation devices.
(Note: While we are focused on the fan in this post, isolating the fan also protects your supporting structure and/or other equipment from the fan’s vibration.)
Vibration Isolation Devices
We use (2) primary vibration isolation devices:
- Rubber-in-Shear Isolators
- Housed Spring Isolators
Both Rubber & Spring Isolators are mounted between the fan and the foundation structure. Rubber Isolators are used with smaller and lighter fans while the Spring Isolators are typically reserved for larger and heavier fans. Both options are relatively inexpensive. The exact specifications depend on the fan’s design, and our design team can help specify the right solution for your application.
Other Important Considerations
There are a few things to discuss with your fan manufacturer if you need vibration isolation devices. They include:
- Fan Arrangement & Base Design – the fan’s arrangement and base are directly affected by vibration isolation devices. Different options are available to give you the best setup.
- Flexible Connectors/Expansion Joints – you will need flexible connections between your fan and ductwork. Rigid connections may lead to cracked/failed ductwork, as the fan will NOT be rigid when mounted to vibration isolation devices.
- Vibration Monitoring & Reporting – vibration isolation devices can mask excessive fan vibration levels. You can install various vibration monitoring & reporting devices to alarm you and even shut-off the fan if vibration levels get too high.
Hear it from the Application Engineer
Senior Application Engineer Fred Besasie takes less than a minute to talk about fan vibration isolation in this one-minute video.
When you’re ready to start your project, reach out and connect with one of our application engineers to discuss the details of your specification.
Related Content on Industrial Fan Applications
There are a number of considerations related to fan foundations and factors affecting vibration. Here are two more videos that might be of interest as you think about your application: