On a New System of Puddling Iron by Steam

Abstract

In order to render the object and nature of this invention more clearly understood, it will be as well to describe and explain the nature and object of the process in the Iron Manufacture termed “puddling,” or the process whereby cast iron is converted into malleable iron. The difference between cast iron and malleable or wrought iron, is chiefly due to the presence in the former of a considerable quantity of carbon in combination with the iron. In order, therefore, to convert cast iron into malleable iron, it is requisite that we remove or drive off the carbon from the cast iron. This object is effected by exposing the surface of a quantity of molten cast iron as it lies in that state on the bottom of a suitable reverberatory furnace, to the action of a current of heated air, so that the oxygen of the air, as it passes over the surface of the molten cast iron, may combine with the carbon and carry it off in the form of carbonic acid and carbonic oxide gases. But as the naturally tranquil surface of the molten cast iron would not present sufficient surface of metal to the action of the air drawn over it by the draft of the furnace, and would, if left in a tranquil state, require a very long time to elapse ere the carbon was by the action of the air abstracted from the cast iron, it is found requisite to agitate the metal, so as ...