What should be paid attention to when polishing thin-walled bearings with uniform cross-sections? What are the noise reduction and sealing technologies?

Precautions for Polishing Thin-Walled Bearings with Equal Cross-Section:

1. Clean Environment:
   Polishing of equal cross-section thin-walled bearings must be carried out in a clean, dust-free indoor environment. Hard dust particles can contaminate polishing materials and damage the nearly finished bearing surface.

2. Dedicated Polishing Tools:
   Each polishing tool should only be used with one grade of diamond polishing paste and must be stored in dust-proof or sealed containers.

3. Changing Grit Sizes:
   When switching to a finer grit size, ensure that the new grit completely covers the previous (coarser) grit. Hands and workpieces must be thoroughly cleaned to prevent contamination.

4. Start with Difficult Areas:
   Begin polishing with difficult areas such as edges, corners, and fillets to avoid over-polishing or under-processing in these spots later.

5. Avoid Rounding Sharp Edges:
   When working on sharp angles and corners, avoid forming unwanted radii or chamfers. Use hard polishing tools and grinding stones whenever possible.

Noise Reduction and Sealing Technology for Equal Cross-Section Thin-Walled Bearings:

1. Noise Reduction Technology:
   Bearing noise is a significant source of environmental pollution and a critical performance indicator, especially in household appliances, office equipment, and instruments. Over the past decade, China’s bearing industry has made significant progress in reducing bearing noise. However, it still lags behind foreign standards. A common user complaint is "abnormal noise"—irregular, sudden sounds or even screeching during bearing operation. Bearing noise is influenced by a wide range of complex factors including the overall bearing design, inner and outer rings, cage, rolling elements, lubricants (grease or oil), materials used, processing techniques, and even the equipment and materials used in manufacturing. Comprehensive analysis and research are required, forming the foundation of bearing noise control technology.

2. Sealing Technology:
   Newly developed rolling bearings are often equipped with sealing devices on both ends. These serve dual functions:

   Common sealing types include rubber or engineering plastic seals and steel-stamped seals (or dust covers).

   Sealing technology is developed to suit various working conditions, considering factors such as sealing structure, sealing performance, material compatibility, and lubricant compatibility.

• Non-contact seals have a gap between the seal and bearing; the smaller the gap, the better the sealing effect, but the shaft's allowable speed decreases.

• Contact seals have no gap between the seal ring and the bearing; a larger contact area provides better sealing, but also reduces the allowable shaft speed.

• Lubrication Protection: Preventing grease or oil from leaking out during use and ensuring that the bearing remains well-lubricated.

• Contamination Prevention: Blocking external dust or harmful gases from entering the bearing cavity, thereby protecting the bearing from damage.