ISO 11951:2016

Overview

ISO 11951:2016 - "Cold-reduced tinmill products - Blackplate" defines requirements for single and double cold‑reduced blackplate supplied in coil form for the manufacture of electrolytic tinplate and electrolytic chromium / chromium‑oxide coated steel (ECCS) per ISO 11949 and ISO 11950. The standard covers dimensional ranges, manufacturing and finishing features, mechanical property requirements, inspection and testing, and packaging/marking rules for coils with nominal minimum rolling widths of 600 mm (500 mm by agreement).

Key topics and technical requirements

• Product scope and definitions: Distinguishes single cold‑reduced (final reduction, anneal, temper‑roll) and double cold‑reduced (second major reduction after annealing) blackplate.
• Thickness ranges:
  • Single cold‑reduced: 0.150 mm to 0.600 mm, in 0.005 mm steps.
  • Double cold‑reduced: 0.100 mm to 0.360 mm, in 0.005 mm steps.
• Coil form and edges: Applies to coils with trimmed or untrimmed edges; coil joint, orientation and labelling requirements specified.
• Manufacturing features: Requirements for annealing, surface finish, oiling and permissible imperfections.
• Mechanical properties and tests:
  • Hardness (Rockwell) and tensile property requirements are specified; hardness tests reference ISO 6508-1, tensile tests reference ISO 6892-1.
  • Flatness and shape tolerances (edge wave, longitudinal/transverse bow, centre fullness).
• Dimensional tolerances: Thickness, feather edge, coil width/length and edge camber tolerances defined.
• Quality assurance: Sampling, test methods, retests, and inspection documents (see ISO 10474) are required to ensure conformity.
• Normative and informative annexes: Include hardness and tensile requirement tables, steel type guidance, springback routine tests and Rockwell equivalent charts.

Practical applications and who uses this standard

• Steel producers / tinmill manufacturers: Use ISO 11951 to specify cold‑reduction, annealing and finishing processes to meet downstream tinplating and ECCS needs.
• Tinplate and ECCS manufacturers: Use it to verify incoming coil quality (mechanical properties, flatness, dimensions) before surface coating to ensure process compatibility and yield.
• Packaging converters and canmakers: Rely on the standard to ensure substrate properties meet forming, coating and corrosion‑protection requirements for food and general packaging.
• Procurement, quality and testing laboratories: Use ISO 11951 for purchase specifications, acceptance testing and inspection documentation to ensure traceability and compliance.

Related standards

• ISO 11949 - Electrolytic tinplate
• ISO 11950 - Electrolytic chromium / chromium‑oxide coated steel (ECCS)
• ISO 404 - General technical delivery requirements (steel)
• ISO 6508-1 - Rockwell hardness test
• ISO 6892-1 - Tensile testing at room temperature
• ISO 10474 - Inspection documents

Keywords: ISO 11951:2016, blackplate, cold‑reduced, tinmill products, electrolytic tinplate, ECCS, coil specifications, thickness tolerances, hardness test, tensile test, flatness.