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Full text of "Modern Mechanical Engineering Vol-I"

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:hines compressed air or pressure water are employed. Associated with
se machines are conveying systems for sand, flasks, and finished moulds,
iltiple moulding (fig. 79), where moulds are poured in piles, is sometimes
ipted for small castings made in quantities.

Machines for Fettling.—In small foundries the castings are cleaned
h little or no aid from machinery, the value of which grows with output.
ten a casting is taken out of the sand in the morning, nothing is done to
>n the moulding area, but it is transported to the fettling shed, where the
es are extracted, the runners and risers cut off, and a general examination
de to ascertain whether it is entirely sound before doing any work upon
If satisfactory, runner marks and fins are removed, together with all
plus lumps and adherent sand. This is done by hand with chipping
sels, coarse files, and scratch brushes of wire. But better methods are

Fig. 78

. Stripping Plates on " International" Machine
rame of machine.   E, Stripping plates lined with Babbit.

In the larger foundries, runners are cut off iron castings with a circular
•^ for those in brass, a git cutting machine is used, which consists of two
Dosed chisels actuated through a reciprocating slide, with power. These