Overview
EN ISO 7590:2018 - Steel cord conveyor belts - Methods for the determination of total thickness and cover thickness (ISO 7590:2018) is a CEN-endorsed international standard (published July 2018) that specifies three validated measurement methods for assessing the total belt thickness and the top/bottom cover thicknesses of steel-cord conveyor belts. This edition supersedes EN ISO 7590:2009 and aligns with ISO 7590:2018.
Key topics and requirements
- Scope: Defines three methods for thickness measurement:
- Method A1 (micrometer) - for total and cover thickness; uses specimen pieces taken across belt width.
- Method A2 (micrometer) - for total and cover thickness; uses full-width specimens with a removed 20 mm top-cover section.
- Method B (optical) - for cover thickness only; direct optical measurement on a cut belt end or specimen.
- Limitations:
- Method B is not suitable when a textile or metal weft is present or if steel cord ends become twisted when cut.
- Measurement points:
- Belt width ≤ 1 000 mm: measure at 3 equidistant points.
- Belt width > 1 000 mm: measure at 5 equidistant points.
- Apparatus:
- Micrometer (Methods A1/A2): dial gauge, flat feet, circular foot 10 mm diameter, pressure (22 ± 5) kPa, graduations of 0.1 mm.
- Optical instrument (Method B): hand-held magnifier with scale 0.1 mm steps, magnification ≥ 8×.
- Test specimens:
- A1: specimens approx. 150 mm long, width equal to two cord pitches.
- A2: specimen ≥ 50 mm long, full belt width.
- B: use the visible belt end in situ or specimen ≥ 50 mm long; cord ends must be clean and visible.
- Measurement principle:
- Total thickness measured directly with micrometer.
- Cover thickness measured by either removing covers and subtracting core thickness (A1/A2) or by direct optical measurement (B).
- Reporting: Arithmetic mean of measurements (3 or 5 points) expressed in millimetres.
Applications and users
- Quality control and acceptance testing of steel cord conveyor belts in mining, bulk handling, quarrying and heavy industry.
- Manufacturers and suppliers verifying product specifications and compliance.
- Testing laboratories performing standardized thickness / cover assessments.
- Procurement, inspection and maintenance teams requiring reproducible measurement procedures for warranty, conformity and performance evaluation.
Related standards
- ISO 8094 - referenced for adhesion-strength testing where the same test pieces may be used (method A1).
- EN 13827 - referenced where cord position measurement aligns with method A2.
- EN ISO 7590:2018 is the accepted CEN version of ISO 7590:2018.
Keywords: EN ISO 7590:2018, steel cord conveyor belts, cover thickness, total thickness, micrometer method, optical method, conveyor belt testing, quality control.
