Heating for the heat treatment of steel usually takes place in gas-fired furnaces. IAS supplies induction furnaces to the CO2 – free reheating or basic heating of steel bars from forging or rolling heat or for heating cold bars.
The induction heating system has the task of bringing the bars to a uniform temperature both axially and radially. For this purpose, the bars are moved into a series of furnaces on roller tables and reversed and rotated when heated. Pivoting and individually driven rollers are between the furnaces to support and rotate the bars during transport. This ensures that the entire volume of the bar is heated evenly. Thermal insulation of the unheated zones between the furnaces minimises radiation losses.
The diameter of the bars can be varied by appropriate process design. The length of the induction system and therefore the number of individual furnaces is determined by the maximum bar length. Shorter bars oscillate between a corresponding number of furnaces, which are controlled by separate inverters. All inverters are synchronised, only the coils that are either occupied by the bar or into which the bar is being inserted become active. Each furnace is equipped with an optical pyrometer for temperature monitoring.