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Ball bearing unit data

Boundary dimensions in accordance with:
  • ISO 3228
    • TU .. M series
  • JIS B 1559
    • TUJ series
  • no standard (neither national nor international), but common in the marketplace
    • WSTUC series
Bearing data
TolerancesTolerances (fig. 1) in accordance with:
  • ISO 3228
    • TU .. M series
      H1 → –0,25 mm1)
      A1 → +0,25 mm1)
  • JIS B 1559
    • TUJ series
      H1 → –0,25 mm1)
      A1 → +0,25 mm2)

    The outside diameter of the bearing is matched to its seat in the housing so that the outer ring is prevented from turning, but is still able to compensate for misalignment.

    1) Tolerance narrower than specified in the relevant standard

    2) Tolerance slightly wider than specified in the relevant standard

Bearing data
Radial internal clearanceBearing data

Cast iron

  • TU(J) series
    • grey cast iron EN-GJL-HB235 in accordance with EN 1561

Composite for the SKF Food Line

  • WSTUC series
    • glass fibre reinforced PP
Components and materials
MisalignmentBearing data

For units with a back seal (designation suffix DFH), the permissible static initial misalignment of the bearing is 1°.

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