Sealed spherical roller bearings have the same features and internal design as basic design spherical roller bearings and are available with a cylindrical bore as standard. Some sizes are also available with a tapered bore or can be supplied with a tapered bore on request.
Sealed spherical roller bearings are supplied grease lubricated and should not be washed. For many application conditions, the bearings do not require relubrication and can be considered relubrication-free (→ Grease life for sealed bearings).
SKF does not recommend heating sealed spherical roller bearings above 80 °C (175 °F) during the mounting process. However, if higher temperatures are necessary, make sure that the temperature does not exceed the permissible temperature of either the seal or grease, whichever is lowest.
- NBR (designation suffix CS or RS)
- HNBR (designation suffix CS5 or RS5)
FKM (designation suffix CS2)
The grease life for sealed bearings is presented as L10, i.e. the time period at the end of which 90% of the bearings are still reliably lubricated. It depends on the load, operating temperature and speed factor. It can be obtained for bearings with standard SKF LGEP 2 grease (designation suffix VT143) from the diagrams. Diagram 1 is valid for light load (P = 0,067 C), diagram 2 for normal load (P = 0,125 C). The grease life is valid under the following operating conditions:
- horizontal shaft
- inner ring rotation
- operating temperature within the green temperature zone of the grease (→ table 1)
- stationary machine
- low vibration levels
- load ratio Fa/Fr ≤ e (→ product table)
- rotational speed below the limiting speed (→ product table) and below the limits listed in table 2
For other operating conditions, the grease life can be estimated by multiplying the relubrication interval for open bearings (→ Relubrication) by a factor of 2,7.
Gp = 0,0015 D B
||grease quantity [g]
||bearing outside diameter [mm]
||bearing width [mm]
The grease should be applied slowly through the lubrication holes in the outer ring, preferably while the bearing is rotating to avoid damaging the seals. SKF recommends relubricating with the same grease as the initial fill.
WARNINGBearings with designation suffix CS2 have seals made of FKM (fluoro rubber). FKM exposed to an open flame or temperatures above 300 °C (570 °F) is a health and environmental hazard! It remains dangerous even after it has cooled.
Read and follow the safety precautions under Seal materials.