METALLURGY OF CAST IRON.
Charcoal iron is made with, charcoal fuel. Its silicon generally ranges from .50 to 2.00, although it is made with silicon as high as 5. oo per cent. The sulphur ranges from a trace up to .08, manganese from a trace, to 1.50, phosphorus .15 to .75. On the whole it can be made richer in iron and poorer in silicon, phosphorus, and sulphur than a coke or anthracite iron. It is chiefly used for the manufacture of such castings as guns and chilled work, and for which it can excel all other brands of iron when melted in an air furnace.
Bessemer is made with coke and anthracite fuel. Its silicon ranges from .75 to 2.50, sulphur .01 to .05, manganese .20 to i.oo, with phosphorus under .10. If it exceeds .10 phosphorus, it is then called " off-Bessemer '' and may be used as a Foundry iron. This pig metal is chiefly used at steel works for making steel and in foundries for ingot moulds, and can often be well used in the place of u foundry iron " in general castings not requiring good or extra fluid metal to run them.
Gray forge iron is a metal of gray fracture with little or no grain, ranging from .50 to 2.00 silicon and from .03 to .20 in sulphur and which is usually high, with low silicon. Its manganese and phosphorus can range as found in general iron. This brand of iron is chiefly used as mill iron in puddling furnaces producing wrought iron, and also for the manufacture of water pipes, etc., often being mixed with higher silicon irons.
Basic iron is of a similar character as gray forge, only its sulphur should not exceed .05, and is generally desired to be low in phosphorus, although it may range from .20 to 2.50. Its silicon is generally desired under i.oo, and manganese may range from .30 to i.oo orction of chilled as well as unchilled castings. analysis which may be given is simply an average of the whole, generally taken from the two ends andith the uncertainty of furnace workings when in urgent need of ten hundred jon of iron; and Sir........................ 2,720 "