casting impeller ductile iron 1.ISO 9001:2000 certification. 2.Material: ductile iron, grey iron, steel 3. Weight: 0.1-150K ... casting impeller ductile iron1.Material: ductile iron, grey iron, steel, under ASTM, ISO,DIN, GOST ... quality is very good and we have ISO 9001-2008 certification. Compared with other companies, our castings are almost no casting ...