The coil of Coreless Induction Furnace consists of rectangular cross section electrolytic copper. Inside the coil water is circulated to avpid its overheating. The coil is firmly fitted on bars which are equally placed around the coil periphery. These bars provide support to coil and avoid deformation of coil.  Inside the coil, the crucible is formed by ramming refractory material.

The induction (generation) of the electrical current in a conductive metal (charge) placed within a coil of conductor carrying electrical current is known as electromagnetic induction of secondary current.

The alternating current applied to the coil produces a varying magnetic field which is concentrated within the helical coil. This magnetic field passing through the charge induces secondary current in the charge piece. The current circulating in the charge produces Produces heat and eventually melt it.

The raw materials which are used for making steel are steel scrap and sponge iron. Sponge iron which is produced in house, in our sponge iron plant, located near to the steel melt shop. Sponge iron and steel scrap charged in the ratio of 70:30 into the induction furnace in batches. 

After the complete melting of charge, the hot liquid metal samples are taken to analyze the chemical ingredients present, i.e. carbon, manganese, silicon, phosphorous, sulphur etc. In order to balance chemistry of the metal as per required grade silico manganese and Ferro silicon is added . The temperature of liquid metal is raised to 1600 degree centigrade for casting.

For ingot casting, the liquid steel is tapped from furnace directly into tundish. And from tundish it is poured into central column of bottom pouring system. The metal rises up into cast iron molds and solidifies in the form of ingots. For billet casting, the liquid steel is poured into the ladle and the ladle is then taken to Continuous Casting Machine – CCM for billet casting.

The following are the steps involved in the operation of a furnace

Charging

Charging is the process by which raw materials such as following. Steel scrap, sponge iron, coke are fed into the furnace. Exposure to toxic metal fumes, carbon monoxide, heat stress, and other toxic gases are the main hazards associated with furnace charging.

Melting

Melting is the process by which the charge material is melted by giving electrical power.

Removal of slag

This is the process by which unwanted debris is removed from the melt. This process is carried out manually.

Refining

Refining is the process in which required alloying additions are done and undesirable impurities are removed from the steel.

Tapping

Tapping is the process of transferring the molten metal into a tunish / ladle from the furnace.

Induction Furnace in Steel Production :

The induction furnace-as a complimentary aggregate for i.e. premelts-plays an important role in steel plants producing high quality and stainless steels. In the field of iron casting and foundries the induction furnace is known as a standard process for making steels.

Induction heating is a subfield of industrially used electric heating. All electrically - conductive materials can be heated quickly and cleanly with pollution free induction heating. Features include