Overview
ISO 18807:2019 specifies requirements for tyres and rims for logging and forestry service in both diagonal and radial construction. The standard covers tyre marking, tyre size designation, dimensional data, load ratings, and rim coordination for forestry and logging tyres. Rim dimensions are given by the companion standard ISO 18804. ISO 18807 is targeted at applications where tyres operate in high-torque (e.g., skidders) and low-torque (e.g., forwarders) forestry services and short road transport.
Key topics and technical requirements
- Marking and size designation
- Defines how to mark conventional, 3-part code and metric tyre sizes (examples: 23.1-26, 30.5L-32, 66x43.00-26 NHS, 710/55–34 LS).
- Specifies load rating markings: ply rating (PR) for many diagonal sizes and load index + speed symbol for metric sizes (example: 710/55–34 LS 161 A8).
- Additional mandatory/optional markings: “TUBELESS”, preferred rotation arrow, and maximum bead-seating pressure pictogram (“XXX kPa MAX”).
- Dimensions
- Design dimensions (section width, overall diameter) for new tyres and maximum in-service dimensions for grown tyres are defined and tabulated (see Annex A).
- Rules for how alternative rim widths affect section and overall widths are provided.
- Load capacities
- Basic tyre loads and inflation pressures are given (Annex B). Requirements distinguish high and sustained torque (skidder service) from transport/low-torque operations.
- Guidance for dual tyre use (basic loads reduced when used as duals) and consideration of mass transfer, winching and grappling forces.
- Rim coordination and tubes
- Rim coordination rules reference ISO 18804; approved rim contours are included (Annex C). Tube requirements and specifications are covered.
- Auxiliary information
- Annexes include measuring rim width codes, tyre parameters for vehicle speed reference (Speed Radius Index in Annex D), and a bibliography.
Practical applications and who uses it
ISO 18807 is used by:
- Tyre manufacturers for design, marking and certification of forestry tyres.
- Rim and wheel producers for rim-tyre coordination and approved rim contours.
- Vehicle OEMs (skidders, forwarders, log loaders) when specifying tyre clearances and load capacities.
- Fleet managers and procurement teams for correct tyre selection and compliance.
- Regulators and testing laboratories for conformity assessment and regional type approval.
Practical use cases include selecting appropriate tyre sizes and load ratings for skidding operations, ensuring correct rim selection, implementing safety markings (bead seating pressure), and designing machines that accommodate in-service tyre growth.
Related standards
- ISO 18804 - Rims for agricultural, forestry and construction machines
- ISO 7867-1 - Metric tyre designation and tyre/rim coordination
- ISO 18805 - Tyre classification for agricultural, forestry and construction machines
- ISO 4223-1 - Tyre industry terminology
Keywords: ISO 18807, forestry tyres, logging tyres, tyre size designation, rim coordination, load ratings, tyre dimensions, bead seating pressure, ply rating.
