Overview
EN ISO 21180:2025 - Light conveyor belts - Determination of the maximum tensile strength (ISO 21180:2025) specifies a standardized test method to determine the maximum tensile strength of light conveyor belts. It applies to belts covered by ISO 21183-1 and to other conveyor belts where ISO 283 is not applicable. This third edition replaces the 2013 version and provides updated procedural wording, environmental test-room requirements, and clarified test steps.
Key topics and technical requirements
- Scope and principle: Measure tensile force as a function of elongation on longitudinal full‑thickness test pieces and determine the maximum tensile strength from the force–elongation graph.
- Apparatus: Use a tensile testing machine (dynamometer) with force‑measurement in accordance with ISO 7500‑1, class 3 or better.
- Test pieces:
- Cut longitudinally from full belt thickness.
- Shape and dimensions as specified in the standard (narrow section width nominally 25 mm).
- Number: five test pieces selected per the distribution in the standard.
- Do not test earlier than five days after manufacture.
- Conditioning: Follow ISO 18573, typically Atmosphere B for 24 h; materials with high moisture absorption (e.g., cotton, polyamide) conditioned for 48 h.
- Test-room conditions: 23 °C ± 2 °C and 50 % ± 5 % relative humidity.
- Procedure:
- Free length between jaws: 220 mm ± 5 mm.
- Apply continuous tensile stress at (100 ± 10) mm/min.
- Prevent slippage (techniques such as rosin and emery cloth are described).
- If samples slip or break outside the central portion, discard and retest.
- Calculations:
- Read maximum force Fmax from the dynamometer graph.
- Compute tensile strength kmax = Fmax / 25 mm (expressed in N/mm).
- Optionally determine elongation at Fmax (percent) using prescribed reference lengths.
- Test report must record belt identification, reference to ISO 21180, test conditions, conditioning period and results.
Applications and users
This standard is essential for:
- Manufacturers of light conveyor belts for product specification and quality control.
- Independent testing laboratories performing conformity and acceptance tests.
- Procurement and maintenance teams specifying belts for packaging, logistics, light material handling and similar industries.
- R&D and material suppliers evaluating belt constructions and coatings.
Using EN ISO 21180:2025 ensures comparable, repeatable tensile-strength data for design verification, supplier qualification, contract testing, and failure analysis.
Related standards
- ISO 283 - Textile conveyor belts - full thickness tensile strength (alternative method)
- ISO 7500‑1 - Calibration and verification of force-measuring systems
- ISO 18573 - Conveyor belts - Test atmospheres and conditioning periods
- ISO 1421, ISO 13934‑1 - Alternative tensile test methods for specific belt/fabric types
Keywords: EN ISO 21180:2025, light conveyor belts, maximum tensile strength, tensile testing, conveyor belts testing, conditioning, ISO 21180.
