Overview
ISO 3739-1:2022 specifies the designation, dimensions and marking for the metric series of pneumatic industrial tyres intended for material‑handling and other industrial vehicles. The standard covers tyres designed for speeds not exceeding 50 km/h and for mounting on 5° tapered or flat base rims. It defines how tyre sizes and service data (load and speed) are expressed and marked, and how design tyre dimensions are calculated and rounded.
Key topics and technical requirements
- Tyre designation format: Dimensional and constructional characteristics (e.g., section width, aspect ratio, construction code, rim diameter code). Example format shown in the standard: 180/65R9.
- Nominal section width: Stated in millimetres and generally ends in 5 (ending in 0 preferred for tyres not used on public roads).
- Nominal aspect ratio: Expressed as a percentage and must be a multiple of 5.
- Construction code: Dash (-) for diagonal ply (or “D”) and R for radial construction.
- Nominal rim diameter codes: Provides rim‑code to rim‑diameter mapping (examples: code 4 → 102 mm, 9 → 229 mm, 15 → 381 mm, 20 → 508 mm, 25 → 635 mm).
- Service description:
- Load index (LI): Numerical code correlated to tyre load‑carrying capacity (TLCC in kg) using the standard’s table.
- Speed symbol: Identifies reference speed; industrial tyres use reference speed A5 = 25 km/h for load identification. The standard lists other symbols up to B = 50 km/h.
- Other markings: “TUBELESS” for tyres not requiring tubes; directional arrows or other service indications as needed.
- Maximum speed marking: If a tyre’s maximum speed is below 50 km/h, the actual maximum speed must be marked (e.g., “max. 40 km/h”).
- Dimension calculations: Design tyre dimensions are calculated per the formulas and rounded to the nearest millimetre in accordance with ISO 80000‑1 rules.
Applications and users
ISO 3739-1:2022 is primarily used by:
- Tyre manufacturers (design, labelling and technical data)
- Rim and wheel manufacturers and OEMs for industrial vehicles
- Fleet operators and rental companies (selection and specification)
- Test laboratories and compliance bodies (measurement and verification)
- Standards committees and regulators working on vehicle safety and interchangeability
Practical benefits include consistent tyre identification, safer tyre‑rim matching, and harmonised load/speed information for industrial tyre procurement and maintenance.
Related standards
- ISO 3739-3 - Industrial tyres and rims - Part 3: Rims
- ISO 3877-1 - Tyres, valves and tubes - List of equivalent terms - Part 1: Tyres
- ISO 4223-1 - Definitions of terms used in tyre industry - Part 1: Pneumatic tyres
- ISO 80000-1 - Quantities and units (rounding rules referenced)
Keywords: ISO 3739-1:2022, industrial tyres and rims, pneumatic tyres, metric series, 5° tapered rims, flat base rims, tyre designation, tyre dimensions, tyre marking, load index, speed symbol.