Rolling Tolerances to EN 10210-2:1997 for hot-finished Square and Rectangular Hollow Sections

 Designation Property   Tolerance  
Depth or width D or B ±1.0% with a min of ±0.5 mm
Thickness t Welded –10%
Seamless –10% but between 10% and 12.5% may occur over not more than 25% of the circumference
Note: Positive deviation is limited by mass tolerance
Squareness of side 90º ±1º
External corner profile 3t max at each corner
Concavity / convexity x ±1% of the side, measured independently of the tolerance on the outside dimension

Section is placed on a flat surface with one end held flat. At the other end the height difference of the two lower corners is taken

Twist v 2 mm plus 0.5 mm per m max
Measured at the centre of the length Straightness (x or y direction) 0.20% L
Mass per unit length Mass of section Welded ±6.0% on individual lengths
Seamless +8.0% -6% on individual lengths
Standard Length L +150 mm –0 mm