Overview
ISO 10799-2:2011 - "Cold-formed welded structural hollow sections of non-alloy and fine grain steels - Part 2: Dimensions and sectional properties" specifies dimensional tolerances and gives tabulated dimensions and sectional properties for standard circular, square and rectangular cold‑formed welded structural hollow sections. The part complements ISO 10799‑1 (technical delivery conditions) and replaces ISO 4019:2001.
Keywords: ISO 10799-2:2011, cold-formed welded structural hollow sections, dimensions and sectional properties, tolerances, circular square rectangular sections.
Key topics
- Scope and purchaser information
- Mandatory purchaser data: type of length and length/length range, and the required section dimensions.
- Tolerances for dimensions and mass
- Outside dimensions, thickness, out‑of‑roundness, concavity/convexity, squareness, external corner profile, twist, straightness and mass per unit length are all covered with tabulated limits.
- Representative tolerances (from the standard): outside dimension typically ±1% (with minimum ±0.5 mm and maximum ±10 mm), thickness ±10% for thin walls or ±0.50 mm for thicker walls, out‑of‑roundness 2% for D/t ≤ 100, squareness ±1°, straightness 0.2% (circular) / 0.15% (square/rectangular), mass ±6%, and weld bead height limits for submerged‑arc welds.
- Measurement methods
- Defines where and how to measure outside dimensions (at least D, B or H from the end with a 100 mm minimum), thickness (not less than 2T from the weld), out‑of‑roundness (formula based on Dmax and Dmin), concavity/convexity, twist and straightness - illustrated by figures and formal formulae.
- Dimensions and sectional properties tables
- Tabulated nominal sizes, mass per unit length, cross‑sectional area, second moments, section moduli (elastic/plastic), torsional constants, radius of gyration, etc. - calculated from the formulae given in Annex A.
Applications
- Who uses this standard
- Structural engineers, fabricators, tube manufacturers, steel suppliers, procurement/specification writers, and quality control inspectors.
- Practical uses
- Specifying and ordering cold‑formed hollow sections for structural frames, trusses, columns, and secondary steelwork.
- Verifying acceptance tolerances during incoming inspection and fabrication.
- Using tabulated sectional properties (or Annex A formulae) for structural design calculations and cross‑section selection.
Related standards
- ISO 10799-1 - Technical delivery conditions for the same product family (see for material/mechanical requirements).
- ISO 10799-2:2011 supersedes ISO 4019:2001 (minor revision).
This part of ISO 10799 ensures consistent dimensional quality and reliable sectional data for designers, manufacturers and purchasers working with cold‑formed welded structural hollow steel sections.