Overview
ISO 5216:2024 - Commercial road vehicles - Ball-bearing turntable - Interchangeability specifies the geometrical dimensions and designation rules for ball-bearing turntables mounted on commercial road vehicles. The standard ensures mechanical compatibility and interchangeability of turntables used in multi-vehicle combinations (per ISO 18868:2013, Clause 4), drawbar trailers that steer the front axle, and turntables assembled with a tractor fifth‑wheel to improve steering manoeuvre.
Key topics and requirements
- Scope and applicability: Covers ball-bearing turntables for trailers, semi‑trailers and certain fifth‑wheel assemblies used to improve steering.
- Radial section types: Defines four standard radial-section geometries (T1, T2, T3, T4). Each type has prescribed overall dimensions and axial load categories documented in Table 1 of the standard.
- Dimensional data: Table 1 lists key dimensions (e.g., DU, DL, PL, PU, d, H) and corresponding axial load ratings. Dimensions that are not specified are left to the component manufacturer.
- Fixing holes: Fixing hole parameters are standardized by hole diameter (“d”) and bolt circle dimensions (“PU” and “PL”); hole distribution remains at the manufacturer’s discretion.
- Designation rules: A clear designation format is defined so components can be identified unambiguously (for example: Ball‑Bearing Turntable ISO xxxxx T1-1005-70).
Applications and practical value
- OEMs and component manufacturers: Use ISO 5216:2024 to design turntables that are mechanically interchangeable across vehicle fleets and supplier ecosystems, simplifying production and inventory.
- Trailer and tractor designers: Ensure correct turntable selection for steering performance and durability in combinations specified by ISO 18868.
- Fleet operators and procurement: Enable faster replacement, reduced downtime and simpler spare‑parts sourcing by relying on standardized form, fit and function.
- Testing and certification bodies: Reference the geometrical requirements and designation rules when verifying interchangeability and issuing conformity documentation.
Practical benefits include improved compatibility across suppliers, reduced engineering rework, streamlined logistics for spare parts, and clearer communication of component specifications.
Related standards
- ISO 18868:2013 - Commercial road vehicles - Coupling equipment between vehicles in multiple vehicle combinations - Strength requirements (referenced for vehicle combination context).
Keywords: ISO 5216:2024, ball-bearing turntable, interchangeability, commercial road vehicles, radial section types, fixing holes, turntable designation, trailer steering, fifth-wheel.
