Cast iron mfr., esp. iron contg. spheroidal graphite - where stream of carrier gas contg. inoculant is heated before being injected into stream of molten iron entering mould or die

摘要

When the molten iron is being poured into a mould or die, a powdered inoculant is added in an inert carrier gas, which is injected into the molten stream of iron. Prior to injection, the carrier gas is heated to ca. the temp. of the molten iron, the inoculant pref. also being heated with the gas. The temp. of the gas is pref. below the m.pt. of the inoculant, which pref. has a grain size of 0.06-0.2 mm. The pref. gas heating appts. consists of a tube made of heat resisting steel or ceramic and 500 mm long. The tube is heated to ca. 1000 deg.C by electric resistance, and the gas and inoculant are dosed into the tube. Uniform distribution of the inoculant in the molten iron, and no unmelted residual inoculant in the cast iron.