NEN EN 754-8 : 2016

Foreword
1 Scope
2 Tolerances on dimensions
    2.1 General
    2.2 Diameter - round tube
    2.3 Width, depth or width across flats - squares,
          rectangles, hexagons, octagons
    2.4 Wall thickness
    2.5 Length
    2.6 Squareness of cut ends
3 Tolerances on form
    3.1 General
    3.2 Straightness
    3.3 Convexity-concavity
    3.4 Twist
    3.5 Angularity
    3.6 Corner and fillet radii
    3.7 Depth of dents for round tubes

NEN-EN 754-8 specifies the tolerances on dimensions and form for aluminium and uminium alloy cold drawn porthole tubes with an outside diameter (OD) from 3 mm to 350 mm (round tube, see Figure 1) or with a cross section contained within a circumscribing circle (CD) from 8 mm to 300 mm (other than round tube, see Figure 2), supplied in straight lengths.