Domestic valve - Common technical standards and technical conditions of ductile iron materials, mechanical properties of attached casting samples

Common technical standards for domestic valve materials Technical conditions of ductile iron, mechanical properties of the attached cast samples Organization QT400-18>30～6039025018130～180 ferrite>60～20037024012QT400-15A>30～6039025015130～180 ferrite>60～20037024012QT500-7A＞30～60450300702170～200 ferrite Note: The letter 'A' indicates the mechanical properties of the grade measured on the additional cast sample to distinguish the mechanical properties measured on the single cast sample.