Dimension standards reflect regional needs:
Flange Width:
US W-shapes (e.g., W24×162) have wider flanges (up to 610mm) for heavy loads.
Chinese HN series (e.g., HN800×300) optimize for narrow flanges to reduce material in long spans.
Section Modulus:
European HEB beams (e.g., HEB300) have higher section moduli than Asian equivalents, suiting heavy industrial use.
Tolerance Requirements:
Japanese JIS standards enforce tighter tolerances (±1mm for flange width), while Chinese GB allows ±2mm for cost-sensitive projects.