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Portable heating plates convert electrical energy into heat energy to heat objects. Is a form of electricity utilization. The temperature distribution of the heated object can be maintained as needed. Electric heating can generate heat directly in the heated object, so the thermal efficiency is high and the heating rate is fast. According to the technical requirements of heating, uniform heating or partial heating (including surface heating) can be achieved. It is easy to achieve vacuum heating and control atmosphere heating. In the process of electric heating, there is little waste gas, residue and smoke, which can keep the heated object clean and do not pollute the environment. Therefore, electric heating is widely used in the fields of production, scientific research and experiment. Electric heating is used especially in the manufacture of single crystal and transistor, mechanical parts and surface quenching, smelting of ferroalloy and manufacture of artificial graphite.

Use the high temperature produced by the arc to heat the object. Arc is the phenomenon of gas discharge between two electrodes. The arc's voltage is low but its current is high. Its strong current is maintained by a large number of ions vaporized on the electrode, so the arc is susceptible to the influence of the surrounding magnetic field. Suitable for high temperature melting of metals. Portable heating plate

Arc heating has direct and indirect arc heating. The arc current from direct arc heating passes directly through the heated object, which must be an electrode or medium of the arc. The arc current of indirect arc heating does not pass through the heated object. Arc heating is characterized by high temperature and concentrated energy. However, the noise of arc is large, and its volt-ampere characteristic is negative resistance characteristic (descending characteristic). In order to maintain the stability of the arc when the arc is heated, the instantaneous value of the circuit voltage when the arc current instantaneous passes zero is greater than the value of the arc starting voltage, and in order to limit the short-circuit current, a certain number of resistors must be connected in series in the power circuit. Portable heating plate