Designs and variants

SKF standard assortment

The SKF standard assortment of CARB toroidal roller bearings matches the assortment of spherical roller bearings. It also includes bearings with a low cross-sectional height to meet requirements for minimum radial space. All CARB bearings are upgraded SKF Explorer bearings and are shown coloured blue in the product table. The standard assortment includes:
  • basic design bearings with cylindrical or tapered bore
    • taper 1:12 (designation suffix K)
    • taper 1:30 (designation suffix K30)
  • sealed bearings
For sizes and variants not listed in the product table, contact SKF.
Basic design bearings

Depending on their series and size the following open CARB toroidal roller bearings are available as standard:

  • bearings with a roller centred cage (fig. 1)
  • bearings with an inner ring centred cage (fig. 2)
  • full complement bearings with a retaining ring (fig. 3)

The load carrying capacity of full complement CARB bearings is considerably higher than that of same-sized bearings with a cage.

Sealed bearings
  • are available, as standard, as small and medium-size full complement bearings with a cylindrical bore
  • are typically used for low speeds and very heavy loads
  • are suitable for both inner or outer ring rotation
  • are fitted with a double-lip contact seal on one or both sides in a recess on the outer ring, sealing against the inner ring raceway
  • are available with two different seal materials / designs:
    • sheet steel reinforced HNBR (designation suffix CS5, fig. 4)
    • sheet steel reinforced NBR (designation suffix NS, fig. 5) with enhanced sealing effectiveness - mainly intended for oscillating or very low speed applications

Bearings sealed on both sides are lubricated for the life of the bearing and are virtually maintenance-free. They are filled with one of the following greases:

  • bearings with HNBR seals → SKF LGHB 2 grease as standard (table 1)
  • bearings with NBR seals → SKF LGEP 2 grease as standard (table 1)
  • other SKF greases on request

For additional information about greases → Selecting a suitable SKF grease.


CARB bearings, if not full a complement of rollers, are fitted with one of the following cages:

  • glass fibre reinforced PA46 cage, window-type, roller centred (designation suffix TN9)
  • stamped steel cage, window-type, roller centred (no designation suffix)
  • machined brass cage, window-type, roller centred (designation suffix M)
  • machined brass cage, inner ring centred (designation suffix MB)

When used at high temperatures, some lubricants can have a detrimental effect on polyamide cages. For additional information about the suitability of cages, refer to Cages.

Customized bearings

SKF can customize bearings to meet the needs of applications where the bearings are subjected to unique operating conditions. For example, bearings for:
  • paper mills or coaters in high precision execution
  • very arduous operating conditions, e.g. continuous casters
  • high temperature applications

For additional information about application-specific CARB bearings, contact the SKF application engineering service.

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