This standard specifies types of nodular cast iron and inspection requirements for them. This standard covers normal, unalloyed and low-alloyed grades of ductile iron cast in sand molds or in molds with similar thermal properties. The tensile strength has an upper limit of 800 N/mm2. The bainitic nodular cast iron, obtained by a special heat treatment, which can have a tensile strength above 800 N/mm2, falls outside the scope of this standard.
NEN 2733-1989 history
1989NEN 2733-1989 Cast iron Spheroidal or nodular graphite cast iron - Grades and requirements