What Is a Bearing Seal?
A bearing seal is a sealing element built into or applied to a bearing to keep lubricant in and contaminants (dust, water, chemicals) out. Integral seals are factory-fitted during bearing manufacture, while external seals (V-rings, labyrinth seals) are added separately.
Types
Contact seals (2RS): Rubber lip presses against inner ring. Best contamination protection. Non-contact shields (ZZ): Metal shield with small clearance gap. Lower friction, less protection. Low-friction seals (RSL, RSH): Engineered lip profile reduces drag while maintaining protection. For additional external protection, see Oil Seal, V-Ring Seal, and Labyrinth Seal.
Frequently Asked Questions
What is the difference between 2RS and ZZ bearing seals?
2RS (or 2RSR, 2RSH) denotes rubber contact seals that press against the inner ring -- excellent contamination protection but slightly higher friction. ZZ (or 2Z) denotes metal shields with a small gap to the inner ring -- lower friction but less protection against fine particles and moisture.