Bearing Cages/Separators

The function of a bearing cage (also known as a separator or a retainer) is to hold rolling elements in proper orientation so they don’t group together.

Bearing cages are produced in a wide variety of materials and for a wide variety of manufacturing processes.

Materials for Bearing Cages:

• Molded plastic – polyamide (nylon), acetal (delrin), polyetheretherketone (PEEK), phenolic resin
• Stamped metal – steel, brass
• Machined metal – steel, brass

Additionally, some metal cages are assemblies (e.g. two halves riveted together.) Furthermore, some ball or roller bearing assemblies do not use a cage / separator. They use the maximum number of rolling elements than can fit in the allotted space. These bearings are called full complement bearings.

Bearing Cage/Separator Applications:

• Rotative bearings
• Linear bearings
• Slide bearings