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Minimum Load Solutions

All bearings require a minimum load to prevent skidding particularly at high speeds.

From many years of experience with fans it has been found that bearings running below 50% of their limiting speed rarely fail from having a low minimum load.

Centrix will therefore not give a warning for this condition when running below 50% of the limiting speed.

Skidding causes rapid wear and is responsible for the majority of bearing failures on arrangement 8 fans.

Coupled fans should always have the bearing nearest the coupling fixed to provide sufficient load. In practice, the radial load created from misalignment cannot be determined due to expansion of the motor as it reaches operating temperature and the initial coupling alignment.

Roller bearings have the highest minimum load requirement followed by Carb bearings then ball bearings.

Try changing bearings to Carb or Ball

Reduce the shaft diameter

For overhung applications try using a small roller bearing at the drive end and a ball bearing at the impeller end (fix the drive end).

Try changing the pedestal length (over hung applications).