Explanation of a Coreless Induction Furnace

Coreless Induction Furnaces


The second type of induction furnace is called coreless induction furnace. Used in the 1980’s, a coreless induction furnace is used as a holding furnace or a melting furnace. Coreless induction furnaces usually have charge made of scrap, pig iron and ferroalloys. Pig iron is the in between product of smelting iron ore.  Ferroalloys are alloys with iron in them. They are mostly used in the production of steel.

The furnace uses an electrical current and magnetic fields to heat the charge. The electrical current is carried in coils, that surround a ceramic crucible. A crucible is refractory lined and is a hollow interior where metal is molten. The hollow section has high conductivity copper tubing which is wound into a helical coils and contained within a steel shell.  The coils let off a magnetic field that creates thermal energy which induces melting.  As seen in channel furnaces a stirring occurs. This stirring allows for molten metal to rise upwards. Slag forms along the top and middle layers of the crucible. This differs from the slag build up found in channel furnaces. Channel furnaces form slag in the throat of the furnace above the induction unit.  To keep the coil from overheating, it is water cooled with recirculating water.

Whaley Products

SA Series
Packaged Chillers
(integrated pump tank)
1.5Ton – 20Ton
Single / Dual Circuits
Single / Dual Pumps
SAE Series
Modular Chillers
(pump & tank on
separate skid)
1.5Ton – 200Ton
Single / Dual Circuits
SAR Series
Split Chillers
(Outdoor Condensing Unit)
(pump, tank, evaporator on
indoor skid)
1.5Ton – 200Ton
Single / Dual Circuits