... .various grade nodular cast iron and grey cast ironwe are currently casting- Grey cast iron types: GG15, GG20, GG23, GG25, GG30- Nodular/Ductile cast iron types: GGG40, GGG40 ... .3, GGG50, GGG60, GGG70, GGG70, GGG80, GGG90sand casting Sand Casting (Grey iron / Ductile iron casting)