In the past the most commonly used type of furnace in the steel industry has been the electric arc furnace, but companies in this industry have become increasingly aware of how an induction furnace can help improve their processes and products.
How Electric Arc Furnaces Work
The melting process begins by having metal charged into the furnace, with additives often included to improve the recovery of the slag. An electric arc from three carbon electrodes melts down the steel. Refractories line the walls of the furnace, and as the melting process continues they gradually decompose and are removed along with the slag.
How Induction Furnaces Work
There are two basic types of induction furnaces:
- Coreless furnaces
- Channel furnaces
- Both rely on alternating currents to create the heat necessary to melt metal. Coreless furnaces contain refractory lined crucibles bordered by copper coils that are cooled by water. Channel furnaces are encircled by inductors to melt metals.
Where Electric Arc Furnaces Are Lacking
Though there are a number of benefits to using electric arc furnaces in the steel industry, for the most part these furnaces have inferior mixing compared to induction furnaces. This is mostly due to the wide and shallow shape of the furnace itself.
Why Induction Furnaces Can Be Beneficial When Melting Steel
There are a number of reasons why an induction furnace can benefit several industries more than an electric arc furnace. An induction heating furnace is far cleaner than an electric arc furnace, emitting fewer particles and other pollutants into the air (which results in a cleaner and safer work environment).
The refining process also moves a lot more smoothly with this type of furnace, as the eddy currents allow for superior mixing. This can make the refining process move along much more smoothly. Inclusions can be more easily decreased in an induction furnace as oxygen and sulphur levels can be lowered without difficulty. As a result, metal companies can achieve tough, clean steel castings more easily in an induction furnace than an electric arc furnace.