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Full text of "Metallurgy Of Cast Iron"

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CHAPTER L.                                   /
In testing iron we have two properties, chemical and
physical, to which we might add the phenomenon of          |
fusion.    An experienced eye can often very fairly tell           ?
what   a casting will   be,   physically,  by judging the          I appearance of the metal when running or at rest in a
ladle.                                                                                  f
In  many cases  the ability  to  judge   liquid  metal          [ will often prove of value, for while we seldom have
means for changing its character when, fluid, we can        "^
often refrain from pouring work when our judgment          !
asserts that a metal   is  radically  wrong.     There  is          ]
this much that can be said of re-melted fluid iron: It          '
will rarely, if ever, deceive an expert, as can the judg-           ing of iron in the pig before being melted.    We can rest assured that if it looks radically soft in a liquid
state, it will not prove hard in a solid one, and vice          \
versa.                                                                                 !
The ordinary moulder can, with a short experience,          ;
tell the  degree  of fluidity,  or whether the  iron  is         
" hot " or " dull/'    Why he should be better able to       r-.j*
do this than judge of its physical qualities When mol-         f
ten, is mainly due to present practice not often afford-         f
ing means to change or correct a metal that might not         *
look right.     The   degree of the temperature before         1 intelligently nianijmluU'u.ounders have had opportunity for experience in crucible work, we will detail more pointsbe found a cheap temporary arrangement for melting from fifty to one hundred pounds of iron,		Ferrochrom.