Bearings with Solid Oil

SKF & MRC products filled with Solid Oil
SKF & MRC products filled with Solid Oil

SKF bearings with Solid Oil are designed for use in applications where high levels of moisture and incidental contact with water and other contaminants are real issues. These bearings are also an excellent choice for applications where relubrication is impractical or dangerous.


Solid Oil is an oil saturated, polymer material that virtually fills all of the free space in the bearing. The polymer material is moulded into the bearing forming very narrow gaps around the rolling elements and raceways, enabling the bearing to rotate freely. The polymer material has a porous structure, with millions of micro-pores, that hold the lubricating oil retained by surface tension. In service, oil is released from the material into the narrow gaps between it and the bearing components, thus providing effective minimum quantity lubrication.

Features and benefits of Solid Oil

  • Longer lubricant life
    • Large amount of oil available
    • Eliminates lubricant churning
    • High quality, synthetic oil resists oxidation
  • Resists washout
    • Solid Oil cannot be washed out of the bearing
    • Water cannot mix with the oil or Solid Oil polymer

  • Virtually eliminates lubricant leakage
    • Solid Oil retains oil in the bearing 
    • Integral bearing seals increase the oil retention even further

  • Protects against the ingress of contaminants
    • Close osculation between Solid Oil and the rollers and raceways significantly reduces the ingress of contaminants
    • Provides additional support for integral bearing seals
Consistent lubricant supply
Solid Oil enables bearing lubrication with an even and consistent film of oil. An increase in operating temperature pushes oil toward the surface of the polymer material. This “flow” of oil within the polymer material occurs because the oil has a higher coefficient of thermal expansion than the polymer material and because the viscosity of the oil decreases with increasing temperature. During shutdown, any excess oil is reabsorbed back into the polymer material.
Longer lubricant life
A bearing with Solid Oil contains two to four times more oil than bearings lubricated with a conventional grease fill. The high quality synthetic oil resists oxidation and the solid structure of the polymer material means that it cannot be overrolled or churned further extending lubricant life. Bearings with Solid Oil are lubricated for the life of the bearing and cannot be relubricated.
Improved performance in wet environments

Solid Oil is beneficial where a bearing is exposed to wet environments since:

  • It cannot be washed out and virtually fills all free space limiting the amount of wet contamination that can enter the bearing 
  • It helps to maintain good lubrication by retaining the oil, distributing it over the bearing surfaces and resisting emulsification 
  • It physically supports integral seals, reinforcing their effectiveness under washdown conditions
Reduced cost of ownership and environmental impact
Bearings with Solid Oil can last significantly longer than grease lubricated bearings in wet environments, thus reducing total cost of ownership and environmental impact.
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