Bearing Selection

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Bearing Basics

Bearing Selection Continued

Bearing Selection

Before beginning the bearing selection process for a particular application it is important to have a good idea of where the bearing will be installed, what its purpose will be, what operating conditions will the bearing be expected to function in, and a desired bearing life. Each bearing type has certain characteristics which make it suitable for a certain application(s). Having comprehensive knowledge of these requirements will aid in bearing selection. In most cases there are several factors to consider when choosing a bearing type. Therefore the following information is to be used only as a guide. In the selection process the following factors must be considered: 1. Equipment constraints 2. Load - Magnitude and Direction Magnitude Direction Radial Thrust Combined 3. Misalignment Static Dynamic 4. Expansion 5. Noise 6. Vibration and shock loading 7. Environment 8. Bearing Type

Equipment Constraints

Sometimes, bearing bore diameter and housing type are predetermined by the equipment and shaft diameter with which the bearing will be used. Small diameter shafts typically are used when light loads are transferred and may lead to the choice of a ball bearing. Higher loads typically dictate larger shaft diameters and then taper or spherical roller bearings may be needed. For mounted bearings, equipment constraints can also dictate what type of housing style can be used (i.e. pillow block, 2-bolt flange, 4-bolt flange, etc.).

Load - Magnitude and Direction

Load magnitude typically dictates size of bearing required but it can also affect the type of bearing. Ball bearings work well in light to moderate loads, roller bearings work well for moderate to heavy loads. Bearings with a full complement of rollers are generally better for higher loads than a caged bearing of the same size and full comple- ment bearings are also recommended for applications with oscillatory rotation. Load direction can be radial, axial, or a combination of these two directions. These directions along with load magni- tude are deciding factors in selection of bearing type.

For more information on Bearing Basics, please contact Application Engineering (800) 626-2093.