Working principle of heating wire is same with other metal heating elements, it is electrothermal phenomenon after metal energized. Electrothermal means that after the current passes through the conductor(electric heating wire), the current generates a certain amount of heat and heat is transmitted. The heating wire itself is metal conductor which emits heat and provides thermal energy when energized.
However, in actual use, if the implementation does not consider the actual use. It is vert easy to make the heating wire melt. Here are main reasons:
1. Sintered material in the furnace reacts with the heating element.
2. The surface power allowed by the heating element is too high, so that the heating wire is melted.
3. The eletric heating element is pre-buried in the thermal insulation material, the use temperature is too high, and the heat is not scattered, so that the electric heating wire is melted.