The surface load value of an electric heating wire determines its heating capacity, heating time, and lifespan. The correct selection of surface load is an important factor in the rational use of electrothermal materials. The surface load of an electric heating wire refers to the power value shared by the wire per unit area, denoted by the symbol ω Mark in W/cm ². For high-temperature resistance furnaces, when the power is the same, selecting a higher surface load means that the size of the heating wire used can be smaller and the material can be saved. However, the surface load is inversely proportional to the service life of the heating wire. If the surface load is selected too high, it will not only fail to save materials but also waste materials due to the decrease in service life. Therefore, the correct selection of surface load is an important factor in the rational use of electrothermal materials.