ISO 17832:2018

Overview

ISO 17832:2018 - Non-parallel steel wire and cords for tyre reinforcement specifies definitions and requirements for non-parallel steel filaments, strands and cords used inside pneumatic tyres. The standard covers classification, designation and ordering, dimensional and mechanical requirements, technological properties, coating/adhesion criteria, sampling and packing. It is intended to ensure consistent performance, interchangeability and traceability of steel cords used in tyre manufacturing.

Key Topics and Requirements

• Classification
  • Tensile strength levels: NT, HT, ST, UT (normal → ultra tensile).
  • Cord structures: single-strand, M+N type, layer, multi-strand.
  • Cord types: HE (high-elongation), OC (open), CC (compact), WC (wavy), HI (high impact).
• Designation and ordering
  • Standardized notation describing cord construction (e.g. 3 + 9 + 15 × 0,175 + 0,15), tensile class, cord type, lay length/direction and coating.
• Dimensions, mass and tolerances
  • Requirements for cord diameter, linear density and permitted tolerances are specified.
  • Recent edition tightened several tolerances (e.g., lay length tolerance narrowed from ±10% to ±5%).
• Mechanical properties
  • Tests and acceptance criteria for breaking load, elongation at fracture, structural elongation and weld/splice strength.
• Technological properties
  • Straightness, arc height, residual torsion, flare, steel cord elasticity and rubber penetration (including wavy cord designs to improve penetration).
  • Tolerances for residual torsion refined for certain constructions.
• Coating and adhesion
  • Brass coating mass fraction, thickness and composition requirements plus adhesion force criteria between steel cord and rubber.
• Sampling and packing
  • Sampling schemes reference ISO 2859-1 and ISO 3951 series; packing and spool requirements specified to protect cord integrity during transport and storage.

Applications and Users

• Who uses ISO 17832:2018
  • Tyre manufacturers and production engineers specifying reinforcement materials.
  • Steel cord manufacturers and suppliers creating product datasheets and order confirmations.
  • Quality/control laboratories performing mechanical and adhesion testing.
  • Purchasing, R&D and regulatory teams ensuring material compliance and interchangeability.
• Practical value
  • Ensures predictable tyre reinforcement performance (strength, fatigue resistance, adhesion).
  • Simplifies procurement and supplier communication via standardized designation and testing.
  • Reduces field failures by setting limits for welds/splices, coating quality and cord geometry.

Related Standards

• ISO 2859-1 (sampling by attributes)
• ISO 3951 series (sampling by variables)
• Prepared by ISO/TC 17 (Steel), SC 17 (Steel wire rod and wire products)

Keywords: ISO 17832:2018, non-parallel steel wire, steel cords, tyre reinforcement, cord tensile strength, brass coating, tyre manufacturing, cord designation.