The role of the steel shell is to be strong and not easy to damage, and it is safe.

Heat loss caused by current flowing through the inductor: This loss is taken away by cooling water. This part of the loss is the main loss of the system, which is related to the inductor structure, physical properties of the charge, and heating frequency. “Electrical efficiency“ is often used to describe this loss. The electrical efficiency is the ratio of the energy transmitted to the heated workpiece to the energy obtained by the inductor from the power supply.