How do CSB-EPB plastic plain bearings achieve long service lives without lubrication?This issue is at the center of our engineers' materials improvement R&D efforts. Thanks to an extensive knowledge of materials' basic characteristics and various basic materials and modified materials optimization technology, as well as accumulation of several decades of materials modification data, CSB's materials development engineers can quickly select and verify abrasion-resistant plastic sleeve materials meeting many kinds of special requirements;
The abrasion-resistant materials used in EPB plastic plain bearings rely on reinforcing fibers and special solid lubricant to achieve excellent wear resistance. The key moment in the operation of a plastic sleeve is the start-up stage.At this time, the bearing begins to operate before the lubricating film is formed, this is the most common situation.Whenever a plastic sleeve must operate under a load, the bearing will suffer small amounts of wear.During the start-up stage, when micro-wear is relatively great, the particles resulting from micro-wear will adhere to the surface of the shaft, which will create an optimal lubricating film when in low-wear operation.After start-up, micro-wear will decrease quickly, and this effect is almost independent of size.During continuous operations after the start-up phase, the wear rate will be low and steady.It should be mentioned that although we require the surface of the shafts paired with plastic plain bearings to have a roughness of Ra0.2-Ra0.6, and the surface will feel very smooth, many microscopic pits will still be present on the surface of the shaft. This is actually a necessary condition for the formation of a hard lubricating film on the surface of the grinding axis during the start-up stage. This explains why we have certain surface roughness requirements: If the surface of the shaft is too smooth, the lubricant cannot stick to the shaft surface and form a lubricating film, which will result in a short bearing service life. But if the surface is too rough, the shaft will create furrow-shaped scratches on the bearing's friction surface, and a continuous lubricating film cannot form, which will also affect the bearing's service life.