... of OEM butterfly valve discs available (normal type, high performance) from DN15 to DN3000 with SS, bronze, iron Features:1) All kinds of ... OEM butterfly valve discs available (normal type, high performance type, and ... customers' drawings, from forgings or castings3) Materials: all kinds of stainless steel (AISI316, AISI316L, AISI304, AISI304L, 17-4PH, ...