EFFECT OF FUEL, FLUXES, TEMPERATURE AND HUMIDITY OF BLAST IN RE-MELTING CAST IRON.
It is as important to possess knowledge of changes caused by re-melting iron as it is to know the chemical constituents of the iron before it is charged into the cupola. For the past seven years the author has followed closely the records which were daily compiled at our foundry of the chemical properties in the iron charged and also the product received from the cupola in C£ heats " ranging from 40 to TOO tons. The following Table, No. 62, compiled from one week's melting in this foundry, with coke .80 to i.oo in sulphur, will
.serve to illustrate the change due to silicon and sulphur
'in re-melting iron:
TABLE 62.—DECREASE IN SILICON, AND INCREASE IN SULPHUR, BY RE-MELTING IRON.
Silicon in pig. Sulphur in pig. Silicon in castings. Sulphur in castings. Loss in silicon. Gain in sulphur.
•93 .022 •77 .040 .16 .018
.Ol6 •65 .046 •19 .030
.78 .031 •58 .056 .20 .025
.52 .029 •39 .061 •r3 .032
.46 .027 •33 .056 .13 .029
.28 .O2I .10 .067 .18 .046
The increase in sulphur in re-melting is dependent61