Electric wire precautions
1. The maximum use temperature of the component refers to the surface temperature of the component itself in dry air, not the temperature of the furnace or the object to be heated. Under normal circumstances, the surface temperature is about 100 degrees higher than the furnace temperature. Therefore, considering the above reasons, the design When using the component, pay attention to its use temperature. When the service temperature exceeds a certain limit, the oxidation amount of the component itself is accelerated, and the heat resistance is lowered. Especially the iron-chromium-aluminum electrothermal alloy component is easily deformed, collapsed, or even broken, and the service life is shortened. .
2. The maximum use temperature of the component also has a considerable relationship with the wire diameter of the component. Under normal circumstances, the wire diameter of the component should be no less than 3mm and the thickness of the flat tape should be no less than 2mm.
3. The corrosive atmosphere in the furnace also has a considerable relationship with the maximum operating temperature of the components, and often affects the operating temperature and service life of the components due to the presence of a corrosive atmosphere.
4. Due to the low temperature strength of iron-chromium-aluminum, the components are easily deformed at high temperatures. If the wire diameter is improper or improperly installed, the components will collapse due to high-temperature deformation, short-circuit phenomenon, etc., so in the component design, it must be considered. Its factors.
5, iron chrome aluminum, nickel, chromium and other series of electrothermal alloys due to their different chemical composition, their use temperature, oxidation resistance to determine the length of use temperature with different azoles of resistivity, determined in the iron chromium hot alloy material The AL element of the resistivity, the composition of the nickel-chromium electrothermal alloy material that determines the resistivity is the Ni element. In the high temperature state, the oxide film formed on the surface of the alloy component determines the service life. Due to the use of the long-term interval, the internal structure of the component is constantly changing, and the oxide film formed on the surface is aging and destroyed. The internal elements of its components are constantly being consumed. Such as Ni, AL, etc., thus shortening the service life, therefore, the choice of wire or a thicker flat belt should be used when selecting the wire diameter of the electric furnace.