Fan & Blower Foundation

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So, your fan or blower arrives on site. Now what? Hopefully you’ve acquired the dimensional data and complete assembled weight, giving you the necessary data for preparing the foundation to which you will mount the fan assembly. The characteristics of the foundation you mount to can have a significant impact on the life of your fan or blower. The higher your vibration levels are, the shorter your life expectancy becomes for rotating components (i.e. wheel, shaft, bearings, couplings, sheaves, belts). To maximize the fan’s life expectancy, consider foundation characteristics such as: levelness, mass, support flexibility, & natural frequency.

As a rule of thumb, slab foundations should weigh at least three to four times more than the weight of your fan assembly to achieve a rigid mounting surface. In cases where a slab mount is not practical, the elevated or structural steel platform should be able to support the fan assembly’s weight while also preventing side sway.

Fans and blowers can be mounted on either a rigid or flexible support. To be considered a rigid mount, the fan and support system should have a fundamental (lowest) natural frequency above the running speed. A flexibly mounted fan requires additional mounting considerations and will have a support system with a fundamental frequency below the running speed.

As with most generic advice, the previous information is based on general assumptions. If you are unsure which mounting characteristics are required for your specific application, it is best to consult with and/or use a fan and blower installation professional well versed in the dynamics of balance, alignment, and vibration analysis. Indventech provides these professional installation services to compliment our premier air movement products. Please contact our sales department at or (888) 864-4344.