... size(mm); 6 ,10 ,15 ,25 ,32 ,40 ,50,65 2,Seat ring diameter3,Rated flow coefficient4, Flow characteristic : Linear ,linear ... .6,4.0,6.4MPaFlange StandardJB/T79.1(2)-94,GB/T9113.1(2)-2000MaterialsZG(230-450),ZG1Cr18Ni9Ti,ZG1Cr18Ni12Mo2Ti etc.BonnetStandard type ...