Deep Groove Ball Bearing: Comparison Between Rubber Seals and Metal Shields
Deep groove ball bearings, originally called single-row radial ball bearings, are the most widely used type of rolling bearings. They feature low friction, high rotational speeds, and can withstand radial loads or combined radial and axial loads. They are also suitable for applications requiring axial load support, such as in small-power motors, automotive transmissions, tractor gearboxes, machine tool gearboxes, general machinery, and tools. Sealed deep groove ball bearings are categorized into rubber-sealed and metal-shielded types. Many customers struggle to differentiate between these two types. Below, Vanlin Bearing Group explain their distinctions.
Function of Bearing Seals
The primary role of bearing seals is to prevent the intrusion of external contaminants (solid or liquid) and retain bearing lubricant.
Types of Bearing Seals
- Non-Contact Seals (seal does not touch the inner ring):
Includes stamped metal shields (metal shields) and non-contact rubber seals.
- Advantages: Dust resistance, higher rotational speeds, quieter operation for metal shields, and lower cost.
- Disadvantages: Cannot prevent liquid ingress.
- Contact Seals (seal lip contacts the inner ring via single or multiple lips):
Includes contact rubber seals and labyrinth seals.
- Advantages: Enhanced dust resistance, protection against liquid contaminants, and quieter operation.
- Disadvantages: Relatively lower speed tolerance and higher cost.
Key Considerations
There is no “superior” seal type—only the most suitable option for specific applications. For example:
- In clean environments, contact rubber seals are unnecessary and would only increase costs.
- Seal performance depends on environmental factors, sealing effectiveness, and friction levels.
Critical Factors in Selection
- Seal structure and material affect wear resistance and friction coefficients. High-speed applications paired with high-friction seals will shorten bearing life.
- Dust/liquid resistance requirements: Choose based on contamination risks.
In summary, the choice between rubber seals and metal shields depends on operating conditions, including rotational speed, environmental contaminants, and cost constraints. Always prioritize compatibility with the application’s demands.