3.
Core are the materials used for making cavities
and hollow projections which can not normally be
produced by pattern alone.
Any complicated contour or cavity can be made
by means of core.
4.
5.
Cores are generally made of sand and even used
in permanent mould.
In general , cores are surrounded on all the sides
by molten metal and therefore subjected to much
more severe thermal and mechanical conditions
and as a result core sand should be of higher
strength than moulding sand.
8. In
case of casting where coring is
required,provision should be made to
support the core inside the mould cavity.
One
of the methods that is universally
followed is to provide core prints where
possible.
