NEN EN 13957 : 2008

Foreword
1 Scope
2 Normative references
3 Technical conditions for inspection and delivery
  3.1 General
  3.2 Production and manufacturing process
  3.3 Coil size and weight
4 Alloys and sizes
  4.1 Alloys
  4.2 Sizes
5 Mechanical properties
6 Tolerances on dimensions and form
  6.1 Diameter
  6.2 Wall thickness

Defines the tolerances on dimensions and form of round aluminium and aluminium alloys porthole extruded tubes with an outside diameter (OD) of over 2 mm up to and including 50 mm supplied in coil form or in straight lengths cut from coiled material.