Things You Need To Know About Rubber-Coated Bearings
1. What is a rubber-coated bearing?
When the existing national standard bearings cannot meet the demand for specific application purposes, the bearings are covered with soft or hard rubber. Hard rubber is mostly engineering plastics, nylon, polyformaldehyde, ABS, etc., while soft rubber is mostly polyurethane PU.
2. Characteristics of polyurethane-coated bearings
- Good moisture-proof, waterproof, and frost-resistant properties;
- The cast polyurethane has strong resistance to deformation, is not easy to crack, and has high viscosity;
- It has good shock absorption and sound absorption properties and can be used in situations with strong vibration;
- It has good wear resistance, oil resistance, and corrosion resistance and can be used in harsh environments;
- The outer diameter of the arc-type rubber-coated bearing has been finished with an arc surface, which reduces the contact area with the workpiece; the type with external thread is easy to install and disassemble.
3. Precautions for using polyurethane-coated bearings
If the working condition is in a high-humidity area, manage the temperature and humidity of the warehouse and use the environment to extend the service life of the product;
The size of polyurethane will change with the surrounding temperature, but the change is not significant, and it can return to its original size after being left at room temperature for a few hours;
The hardness tolerance is generally around ±5°Shore, the normal value.
4. ApplicScenariosnarios
Drawer pulleys, shower room hanging wheels, track wheels, rolling conveyors
5. Analysis of common problems with rubber-coated bearings
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Polyurethane bearings will turn yellow. Is this a product quality problem?
Answer: The color of polyurethane-coated bearings will darken and turn yellow over time and under natural light or lighting. This is a normal phenomenon and will not affect its physical properties. To avoid this kind of phenomenon, try to avoid direct light exposure.
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Why do polyurethane bearings become sticky? Can it be avoided?
Answer: This is because polyurethane will hydrolyze and deteriorate if used in a humid environment for a long time, destroying its internal structure. You can consider replacing it with silicone-coated bearings.
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Is the hardness of polyurethane-coated bearings a fixed value? In addition, what is the relationship between hardness and friction?
Answer: The hardness tolerance of polyurethane-coated bearings is generally around ±5°Shore. As the hardness increases, the friction will decrease.
CNB provides a detailed introduction to rubber-coated bearing models and sizes; please click on the link below: