The bore diameter and the width of the inner rings are made to Normal tolerances in accordance with ISO 492:2002.
The inner ring raceway diameter tolerances are provided with the product data. The roughness Ra of the inner ring raceway surface is between 0.2 and 0.8 μm.

Diameter tolerances for inner ring seats

Inner rings should have an interference fit. For sufficient interference, the following shaft tolerances should be applied:
  • k6 for d ≤ 25 mm
  • m6 for d > 25 mm
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