ISO 18286:2008

Overview

ISO 18286:2008 specifies tolerances on dimensions and shape for hot-rolled stainless steel plates (quarto plates) produced on a reversing mill. It covers plates with nominal thicknesses from 4 mm to 250 mm and nominal widths ≥ 600 mm. The standard defines dimensional tolerances (thickness, width, length), shape tolerances (flatness, edge camber, out‑of‑squareness), measurement methods and purchaser/manufacturer obligations. It explicitly excludes round plates, custom-made plates, checker/bulb plate for flooring, wide flats and continuous-process (coiled) plates.

Key Topics

• Scope and applicability: Hot‑rolled stainless steel plates made on reversing mills; plates slit from wider stock with width < 600 mm require agreement between purchaser and manufacturer.
• Designation and purchase information: Purchaser must supply nominal thickness, width, length, edge condition (trimmed or mill edge “NK”), tolerance classes for width/length (Class A, B, C) and flatness (Class N or S).
• Thickness tolerances: Specified by nominal thickness and plate width ranges; minimum thickness requirements apply across plate areas unless otherwise agreed.
• Width and length tolerances: Three tolerance classes:
  • Class A (standard trimmed edges),
  • Class B (flame‑cut),
  • Class C (abrasive‑cut) - each with prescribed upper/lower limits.
• Shape tolerances:
  • Edge camber: For trimmed plates, maximum 0.5% of nominal length.
  • Out‑of‑squareness: For trimmed plates, maximum 1% of nominal width.
  • Flatness: Normal (Class N) and special (Class S) flatness tables; limits depend on steel type and measuring length. Steel type B is defined by composition (e.g., Ni > 20% or Mo > 2% or N > 0.11% mass fraction).
• Measurements: Methods and measuring points (e.g., thickness measurements >10 mm and <75 mm from a longitudinal edge; length defined as largest inscribable rectangle).
• Excess mass: Defined as percent difference between delivered and theoretical mass; theoretical density per ISO/TS 15510.

Applications / Who Uses It

ISO 18286 is used by:

• Steel producers and rolling mills for production and QA of hot‑rolled stainless plates.
• Procurement and specification writers in construction, shipbuilding, pressure vessels, heavy fabrication and industrial equipment.
• Quality inspectors, testing labs and fabricators to verify compliance with dimensional and shape tolerances.
• Design engineers who need reliable material tolerances for fit, welding, forming and assembly.

Keywords: ISO 18286:2008, hot-rolled stainless steel plates, tolerances, flatness, edge camber, quarto plates, thickness tolerances.

Related Standards (if applicable)

• ISO/TS 15510:2003 - Stainless steels - Chemical composition
• ISO 16143-1:2004 - Stainless steels for general purposes - Flat products
• ISO 9444 - (related continuous-process plate tolerances)