Nodular cast iron mfr. - where powdered prealloy contg. magnesium is fed via carrier gas into stream of molten iron entering mould

摘要

Molten iron is fed as a stream from a vessel fitted with a stopper into a mould. The required amt. of a pre-alloy necessary to obtain spheroidal graphite, is fed by a carrier gas, esp. an inert gas, into the stream of molten iron; and the gaseous reaction prods. obtd. by feeding the pre-alloy into the iron are pref. removed by suction above the mould. The object is to add magnesium as a pre-alloy powder without the burning off of Mg. The reaction begins in the molten stream of metal and ends in the runner system in the mould. The inert gas may be nitrogen; but compressed air may also be used as the carrier gas.