A foundry is an establishment where casting of both
ferrous and non ferrous metal is affected. Both ferrous and non ferrous
metals are common alloys used for castings.
In foundries, there is a mold in which molten metal is poured. Such
molds may be constructed out of sand, metal (permanent molding) or other
ceramic or refractory materials. The pouring is normally accomplished
with gravity, or may be assisted with vacuum or pressurized gases. The
freezing of metals results in castings.
Since foundries deal with particular metals they have furnaces
dedicated to these. For instance an iron foundry (for cast iron) may use
a small blast furnace, whereas steel, bronze or brass foundry use an
electrical induction furnace or in some cases a gas heated crucible
furnace. Most aluminum foundries use either an electric resistance or a
gas heated crucible furnace.
The design of the Furnaces depend upon the type of metal being cast and
the fuel available that will produce the desired temperature. The
temperature range of the furnace vary from few hundred degrees to over
3000 degrees.
The heat is generated in the furnace by using both electricity and the
fuel. The fuel normally used are natural gas or propane, charcoal, coke,
fuel oil and sometimes wood. These furnaces use insulation system to
trap the heat for longer time. Furnaces can be any size, ranging from
mere ounces to hundreds of tons
Types
Popular types of furnaces that are used in foundries are:
