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

  • 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
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