Overview
ISO 3739-2:2021 is an international standard developed by ISO that specifies the load ratings for pneumatic industrial tyres of the metric series. These tyres are intended primarily for industrial vehicles operating on prepared surfaces. This second edition updates and replaces the 1992 version and includes expanded rim diameter codes, reflecting advancements in tyre technology and wider industrial applications.
This standard covers pneumatic tyres mounted on 5 degrees tapered or flat base rims, commonly used in industrial environments such as warehouses, loading docks, and manufacturing facilities. ISO 3739-2:2021 focuses on defining the permissible load ratings based on tyre size, inflation pressure, and vehicle operating conditions to ensure safety, reliability, and optimized tyre performance.
Key Topics
- Load Ratings: Defines permissible loads for pneumatic industrial tyres as a percentage of the tyre’s reference load carrying capacity, adapted for various vehicle types (e.g., counterbalanced lift trucks, side loaders) and speed capabilities.
- Reference Load Capacity: Establishes the 100% load capacity of a tyre linked to its load index as described in ISO 3739-1, including specific inflation pressures from 550 kPa to 1,000 kPa.
- Tyre and Rim Compatibility: Applies exclusively to metric series pneumatic tyres mounted on tapered or flat base rims with rim diameter codes ranging from below 20 to 33.
- Operating Inflation Pressure: Stresses the importance of agreeing on cold inflation pressure between tyre and vehicle manufacturers. Inflation pressure affects tyre load capacity and must factor in operating conditions, vehicle characteristics, and tyre placement.
- Dual Tyre Load: Specifies the load distribution when tyres are fitted in dual combinations, doubling the permissible load compared to a single tyre.
Applications
ISO 3739-2:2021 is critical for industrial vehicle manufacturers, tyre suppliers, and fleet operators who require standardized guidance on tyre load capacities to achieve safety and efficiency. Typical applications include:
- Industrial Forklifts and Lift Trucks: Guidance on load capacity ratings for counterbalanced and side-loader lift trucks at various operating speeds.
- Warehouse and Logistics Equipment: Reliable load ratings to prevent tyre failure during heavy load handling and maneuvering on smooth, prepared surfaces.
- Material Handling Vehicles: Ensuring tyre selection matches payload, speed, and usage conditions for optimal vehicle performance and tyre longevity.
- Design and Manufacturing: Assists rim and tyre manufacturers in meeting global standards for pneumatic tyre load capacities to promote interoperability and industry consistency.
Industry professionals use ISO 3739-2:2021 to:
- Select appropriately rated pneumatic tyres for specific vehicles and operating speeds.
- Determine inflation pressures tailored to operational load and service conditions.
- Establish maintenance protocols focused on load adherence to prevent premature tyre wear or safety risks.
Related Standards
ISO 3739-2:2021 is part of the ISO 3739 series addressing industrial tyres and rims, working in conjunction with:
- ISO 3739-1: Designation, dimensions, and marking of pneumatic tyres (metric series) mounted on 5 degrees tapered or flat base rims. This standard provides the essential tyre size and marking specifications related to load ratings.
- ISO 3739-3: Rim contours for pneumatic tyres covered under this series, detailing the rim shapes and dimensions compatible with the tyres.
- ISO 4223-1: Terminology and definitions for pneumatic tyres essential for understanding tyre characteristics and load rating parameters.
- ISO 5053-1: Vocabulary for industrial trucks that helps contextualize vehicle types referenced within load rating tables.
For comprehensive tyre and rim standards compliance, manufacturers, operators, and safety engineers are encouraged to consult the entire ISO 3739 series.
By adhering to ISO 3739-2:2021, industries benefit from standardized load rating guidelines that enhance operational safety, ensure appropriate tyre selection, and extend the service life of pneumatic tyres used on industrial vehicles operating on prepared surfaces. This standard is pivotal for worldwide harmonization of industrial tyre performance and safety criteria.
Open preview (PDF)Industrial tyres and rims — Part 2: Pneumatic tyres (metric series) on 5 degrees tapered or flat base rims — Load ratings