Overview
SIST ISO 15:2020 - "Rolling bearings - Radial bearings - Boundary dimensions, general plan" is the fourth edition (2017) international standard that specifies preferred boundary dimensions for single- and multi-row radial bearings across the defined diameter series. The document restricts and harmonizes bearing sizes to support economic production while meeting the dimensional needs of bearing users. Tables of nominal dimensions (d, D, B) and chamfer values (r, s_min) are provided in millimetres for diameter series 7, 8, 9, 0, 1, 2, 3 and 4.
Key topics and technical requirements
- Scope and purpose: Defines preferred boundary dimensions for radial bearings in the listed diameter series to promote interchangeability and efficient manufacturing.
- Dimension tables: Tables 1–8 give nominal values for bore (d), outside diameter (D), width (B) and chamfer dimensions (r, s_min) for each diameter series.
- Chamfer rules and exceptions:
- Chamfer dimension r applies at specified ring corners and is listed in the tables.
- Some bearing types are excluded or have different chamfer rules (e.g., rings with snap ring grooves, loose rib/non-rib cylindrical roller sides, non-thrust side of angular contact outer rings) and must follow the referenced ISO documents.
- Symbols and terminology: Uses symbols from ISO 15241 and terms from ISO 5593; nominal dimensions are indicated in the figures and tables.
- Extension guidance: Annex A (informative) provides guidelines for extending the standard to additional radial bearing sizes, including very large bearings (tables extended in this edition).
- Normative references: Includes related ISO standards such as ISO 464, ISO 5593, ISO 12043, ISO 12044 (used for specific exceptions).
Practical applications - who uses SIST ISO 15:2020
- Bearing manufacturers: For standardized production ranges, tooling, and quality control.
- Mechanical and machine designers / OEMs: To ensure bearing interchangeability and correct shaft/housing fits during component selection and CAD modelling.
- Procurement and supply chain: For specifying standard bearing sizes and ensuring compatibility across suppliers.
- Maintenance and asset engineers: To identify replacement bearings with standardized boundary dimensions.
- Standards committees and testing labs: For harmonized measurement and compliance checks.
Related standards (referenced)
- ISO 5593 - Rolling bearings vocabulary
- ISO 15241 - Symbols for rolling bearings (referenced for symbol usage)
- ISO 464, ISO 12043, ISO 12044 - Specific geometrical/tolerance and chamfer provisions for certain bearing types
By adopting SIST ISO 15:2020, organizations benefit from consistent bearing dimensions, improved interoperability, reduced part proliferation, and clearer design and procurement specifications for radial rolling bearings. Keywords: SIST ISO 15:2020, rolling bearings, radial bearings, boundary dimensions, diameter series, bearing chamfer, bearing design, ISO standard.