ISO 21181:2025 pdf download,Light conveyor belts — Determination of the relaxed elastic modulus.
ISO 21181:2025 specifies a test method for determining the relaxed elastic modulus of light conveyor belts. Its purpose is to provide a standardized way to quantify how these belts deform under a defined loading and after the initial stress relaxation, so the measured stiffness characteristic is comparable between tests and laboratories. The standard applies to light conveyor belts whose modulus evaluation follows ISO 21183-1 or other belt types where ISO 9856 is not applicable. It defines the general approach, including selecting test specimens, applying the appropriate conditioning/loading procedure, measuring the belt’s elastic response, and calculating the relaxed modulus from the resulting force–deformation (or equivalent) data. By standardizing this measurement, ISO 21181:2025 supports consistent material selection, product specification, quality control, and performance assessment for conveyor system design and operation.