Self-lubricating bearings are a new generation of products that use specially formulated alloy copper or steel plates as a base and embed solid lubricants. They break through the limitations of conventional bearings that rely on oil film lubrication. Under the action of friction, the solid lubricant expands and automatically transfers to the friction surfaces to form a lubricating film, preventing metal-to-metal contact, thereby reducing the coefficient of friction and wear, and improving the bearing's load-bearing capacity.
Self-lubricating bearings generate friction during operation due to the contact between the journal and the bearing shell, leading to surface heating, wear, and even seizing. Therefore, when designing bearings, it is necessary to select sliding bearing materials with good friction reduction properties to manufacture the bearing shells, use suitable lubricants and appropriate supply methods, and improve the bearing structure to obtain thick film lubrication.
1. Scoring on journal surface: Ferrochromatogram shows iron-based cutting abrasive grains or black oxide particles, and tempering color is present on the metal surface.
2. Bearing wear: Due to the metallic properties of self-lubricating bearings (high hardness, poor yielding), they are prone to adhesive wear, abrasive wear, fatigue wear, fretting wear, and other conditions.
3. Corrosion on the roof tile surface: Spectroscopic analysis revealed abnormal concentrations of non-ferrous metal elements; many submicron-sized wear particles of non-ferrous metal components appeared in the spectrum; the lubricating oil had excessive water content and acid value.
4. Bearing back fretting wear: Spectroscopic analysis revealed abnormal iron concentration, with many submicron iron wear particles in the iron spectrum, and abnormal moisture and acid value of the lubricating oil.
5. Bearing failure: The ferrograph of sliding bearings contains a large number of large alloy abrasive grains and ferrous metal oxides.
6. Tile surface spalling: The ferrography revealed many large-sized fatigue spalling alloy wear particles and layered abrasive grains.
7. Bearing surface scoring: Cutting abrasive grains were found in the ferrography, and the abrasive grains of the sliding bearing were composed of non-ferrous metals.
8. Journal surface corrosion: Spectroscopic analysis revealed abnormal iron concentration, with many submicron iron particles in the ferrospectral data, indicating excessive moisture or acid value in the lubricating oil of the sliding bearing.
