Industrial flat plate heater

Overview:

Heating objects with high temperatures generated by an electric arc. An electric arc is a gas discharge phenomenon between two electrodes. The voltage of the arc is not high, but the current is large, maintained by a large amount of evaporated ions on the electrodes, thus making the arc susceptible to the influence of the surrounding magnetic field. When an electric arc forms between the electrodes, the temperature of the arc column can reach 3000 to 6000 K, suitable for high-temperature melting of metals.

Arc heating includes direct and indirect arc heating. Direct arc heating involves the arc current passing directly through the heated object, which must be either an electrode or a medium in the arc. Indirect arc heating does not pass the arc current through the heated object, relying mainly on the heat radiation from the arc. The characteristics of arc heating are: high arc temperature, concentrated energy, and the surface power of the molten pool in steelmaking arc furnaces can reach 560 to 1200 kilowatts per square meter. However, arc heating has the drawback of significant noise and a negative resistance characteristic (decreasing characteristic) in its voltage-ampere characteristic. To maintain stability during arc heating and ensure that the instantaneous circuit voltage is greater than the striking voltage when the arc current passes through zero, and to limit short-circuit current, it is necessary to串联 a certain value of resistor in the power supply circuit.