Introduction to types of electric furnaces

Industrial resistance furnace
② Due to the relatively small resistance of the material itself, in order to achieve the required electric heating power, the working current is quite large, so the power transmission electrode and the material should be in good contact to avoid arcing and burning the material, and the resistance of the power transmission bus should be small to reduce circuit losses; Most resistance furnaces are indirect heating resistance furnaces, which are equipped with a resistor specifically designed to achieve electrical heat conversion, called an electric heater, which transfers heat energy to the materials in the furnace.
The furnace shell of this electric furnace is made of steel plate, and the furnace is lined with refractory materials such as ceramic fibers, with materials placed inside.
The most commonly used heating elements are iron chromium aluminum heating elements, nickel chromium heating elements, silicon carbide rods, molybdenum disilicide rods, and silicon carbon rods, zirconium diboride ceramic composite heating elements. According to needs, the atmosphere in the furnace can be ordinary atmosphere, protective atmosphere, or vacuum. The general power supply voltage is 220 V or 380 V. If necessary, an intermediate transformer with adjustable voltage is configured. Small furnace (<10 kW) single-phase power supply, large furnace three-phase power supply. For materials with a single variety and a large batch size, continuous furnace heating should be used. For resistance furnaces with furnace temperatures below 700 □, most are equipped with blowers to enhance heat transfer in the furnace and ensure uniform heating. Resistance furnaces for melting fusible metals (lead, lead bismuth alloys, aluminum, magnesium, and their alloys) can be made into crucible furnaces; Or it can be made into a reverberatory furnace with a molten pool, and an electric heating body is installed on the top of the furnace. Electroslag furnace is a resistance furnace that realizes electrothermal transformation by dissolving slag (see Electroslag Remelting).