Cookies on the SKF website

SKF uses cookies on our websites to align the information shown as closely as possible to our visitors’ preferences, such as country and language choices.

Will you accept SKF cookies?

Bearing data

Dimension standards

  • (R)NA 22 designs
    ISO 15, dimension series 22, except for the outer ring width
  • NATR, NATV, NUTR .. A, PWTR designs
    ISO 7063 and ANSI/ABMA Standard 18.1 (where standardized)
  • (R)STO designs
    Not standardized

Profile of the outer ring running surface

  • (R)STO, (R)NA 22, NATR, NATV designs
    Radius = 500 mm
  • NNTR design
    D ≤ 260 mm → Radius = 10 000 mm
    D ≥ 290 mm → Radius = 15 000 mm
  • NATR .. PPA, NATV .. PPA, NUTR .. A, PWTR designs
    Improved crowned profile for better load distribution, higher stiffness and reduced wear
Tolerances

For additional information → Tolerances
Normal, except:
  • diameter of the crowned running surface:
    • NNTR design → h10
    • other designs → 0/–0,05 mm
  • width B:
    • NNTR design → 0/–0,5 mm
    • NATR, NATV, NUTR .. A, PWTR designs → h12
  • inside diameter Fw:
    • RSTO, RNA 22 designs → F6

Values for Normal tolerance class: ISO 492 (table 1)

Values for ISO tolerance classes: h10, h12 and F6 (table 2)

Internal clearance

For additional information → Internal clearance

  • STO and NA 22 designs
    Normal
  • Other designs
    Between C2 and Normal

Values: ISO 5753-1 (table 3)


Values are valid for unmounted bearings under zero measuring load.
Defect frequenciesPerform calculations
SKF logo