Furnaces and Tools in Casting

slides 114 - 122

Furnaces for Casting

 Cupolas

 Direct fuel-fired furnaces

 Crucible furnaces

 Electric-arc furnaces

 Induction furnaces

Cupola for melting cast iron

Three types of crucible furnaces

Induction Furnace

Two types of ladles

direct fuel fired furnaces

small open-hearth in which charge is heated by natural gas fuel burners located on side of furnace

bottom of furnace has a tap hole to release molten metal

roof helps in heating by reflecting flames down against charge

Crucible furnace

Metal is melted w/o direct contact with burning fuel mixture, container is made out of refractory material

A.K.A. indirect fuel furnace

Three types of Crucible furnaces

Lift out, stationary pot (must use ladle), tilting pot

Electric Arc Furnace

Charge is melted by heat from electric arc

High electrical power consumption

melts steel

Induction Furnaces

Uses alternating current passed through a coil to develop magnetic field in metal

Induced current causes rapid heating and melting, electromagnetic force field also causes mixing

can be used to get melted metals of high quality and purity

Two common types of ladles to transfer molten metals

Crane, Two-man