Both the electric arc furnace and the intermediate frequency furnace are two classifications of electric furnaces in steelmaking equipment, but they still have different points. The following is the analysis of the difference between the electric arc furnace and the intermediate frequency furnace.
Electric Arc Furnace
An electric arc furnace is an electric furnace that smelts ore and metal at a high temperature generated by an electric arc. When the gas discharge forms an arc, the energy is concentrated, and the arc temperature is above 3000 °C. For smelting metals, electric arc furnaces have greater flexibility than other steelmaking furnaces and can remove impurities such as sulfur and phosphorus. The furnace temperature is easy to control, and the equipment has a small footprint, which is suitable for the melting of high-quality alloy steel.
Intermediate Frequency Furnace
The intermediate frequency furnace is a power supply device that converts the power frequency 50HZ alternating current into an intermediate frequency (300HZ or more to 1000HZ), converts the three-phase power frequency alternating current into a direct current, and then converts the direct current into an adjustable intermediate frequency current, which is supplied by the capacitor and The intermediate frequency alternating current flowing in the induction coil generates high-density magnetic lines in the induction coil, and cuts the metal material contained in the induction coil to generate a large eddy current in the metal material.
Classification
There are many ways to classify electric arc furnaces.
Divided by Electric Melting Forms
(1) Non-consumable electric arc furnace, which uses electricity such as tungsten or graphite, and the electricity itself is not consumed or consumed very little during the smelting process.
(2) Self-consumption electric arc furnace, which uses electricity from the smelted metal, and the metal edge is melted and consumed by itself.
According to the control method of arc length
(1) Constant arc voltage automatic control type electric arc furnace, which relies on comparing two voltages with a given voltage, and the difference is driven by signal amplification to drive the self-consumption electric power to keep the arc length constant.
(2) Constant arc length automatic control arc furnace, which relies on constant arc voltage to approximately controlling the constant length of the arc.
(3) Droplet pulse automatic control arc furnace, which automatically controls the constant arc length according to the pulse frequency generated during the formation and dripping of the metal droplet and the relationship between the pulse duration and the arc length.
Divided by Working Forms
(1) A periodic operating arc furnace, that is, each smelting furnace as a cycle.
(2) Continuous working electric arc furnaces, which have two forms. The kind is the rotary type of the furnace; the other is that the two furnaces share the DC power supply, that is, after the melting of the furnace is finished, the power is switched to another furnace and the melting of the furnace is started immediately.
Divided by Furnace Structure
(1) Fixed electric arc furnace.
(2) Rotary electric arc furnace.
The intermediate frequency furnaces are only classified by type, which is classified according to tonnage. For details, please refer to the classification of intermediate frequency furnaces.
Advantages
Electric Arc Furnace
The electric arc furnace steelmaking process is short, the equipment is simple, the operation is convenient, the pollution is relatively easy to control, the construction investment is small, the floor space is small, and it is not necessary to rely on the complicated ironmaking system like the converter steelmaking.
EAF steelmaking has strong adaptability to the charge. It uses scrap steel as the main raw material, but it can also use solid water such as molten iron (blast furnace or iron furnace), sponge iron (DRI) or hot compact (HBI), and pig iron. And liquid iron-containing raw materials.
Modern electric arc furnaces can also use a large number of auxiliary energy sources, such as blown heavy (light) oil, coal powder, natural gas, and the like. Therefore, the electric arc furnace steelmaking process has strong adaptability, flexible operation, and wide application.
The electric arc furnace can not only smelt high-quality steel with low phosphorus, sulfur and oxygen content but also alloys with various elements (including easily oxidized elements such as lead, boron, vanadium, titanium and rare earth) to produce various high-quality products. Steel and alloy steel, such as ball-bearing steel, stainless acid-resistant steel, tool steel, electrical steel, heat-resistant steel, magnetic materials, and special alloys.
Intermediate frequency furnace
Fast heating, high productivity, less oxidative decarburization, material and cost savings, and extended die life
Excellent working environment, improve workers’ working environment and company image, no pollution, low energy consumption
Uniform heating, small core temperature difference, high-temperature control accuracy
