Skip to main content

Full text of "Metallurgy Of Cast Iron"

See other formats

life to the fluidity of the metal than can be obtained in re-melted iron.
To utilize direct metal, some have thought it would be a good plan, in order to overcome the difficulty from " kish " and obtain a more uniform product, to first pour the metal coming from two or more furnaces into a large receiver or reservoir so arranged as to closely confine from 50 to 100 tons ^of iron, one idea being that if the metal should have '' kish '' in one furnace, another would be free of it to mix with it, and hence an average could be obtained which would be sufficiently free from "kish" to obviate any defects in the casting. The information which the writer has obtained as to the success of this plan is not very favorable. The difficulty found consisted in the metal losing too much fluidity and life by the extra handling and detention of the metal in the fluid state. Where work is very massive, not requiring good *' hot iron, this reservoir method may be of much value; but the difference which exists in the cost of direct metal and cupola iron does not warrant any very great chances being taken in losing castings on account of the fluidity and uniformity of a " grade " not being as desired. However, for castings like ingot moulds and pipes, " direct metal" in days of close margins may command attention in some cases.
It is no uncommon thing for us in our foundry to make small castings with direct metal carried by three men in a " bull ladle," taken from a furnace close by us. The plan which we adopt to obtain such small bodies of metal is simply to catch the metal with a "hand ladle" by dipping the iron out of the main runner as it flows to the pigs and pouring it into aourtesy of Mr. Edgar S. Cook, president of the Warwick Iron Co. of Pottstown, Pa. is often surprising how rapidly, as about 75 per cent of the heat generated from the solid fuel is utilized. This is attained where one ton of coke will produce one ton of iron; and Sir........................    2,720     "