Intermediate frequency induction heating equipment uses induction current to heat treat the surface of the workpiece locally. This heat treatment process is often used for surface quenching, but also for local annealing or tempering, and sometimes for overall quenching and tempering. With the development of industry, the technology of induction heating and heat treatment is continuously improved, and the application range is also continuously expanded.

The choice of intermediate frequency power equipment is related to the depth of the heating layer required by the workpiece. For workpieces with deep heating layers, power equipment with lower current frequency should be used; for workpieces with shallow heating layers, power equipment with higher current frequency should be used. Another condition for selecting a power supply device is the device power. The increased heating surface area requires a corresponding increase in power supply. When the heating surface area is too large or the power supply is insufficient, continuous heating can be used to move the workpiece and the sensor relatively, heating the front side and cooling the rear side. But * the entire heating surface is heated once. In this way, the residual heat of the core of the workpiece can be used to temper the hardened surface layer, thereby simplifying the process and saving energy.

In order to ensure the heat treatment quality and improve the thermal efficiency during the work process of the steel bar heat treatment equipment, an appropriate structured inductor must be designed and manufactured according to the shape and requirements of the workpiece. Commonly used sensors are external surface heating sensors, internal hole heating sensors, and planar heating sensors.