In the early 19th century, Michael Faraday discovered the phenomenon of electromagnetic induction, knowing that an alternating magnetic field induces a current caused by heating a conductor. However, electrical equipment has long been regarded as heat loss, and everything possible is done to reduce fever and improve efficiency.
Until the end of the 19th-century heating began to develop, and the use of this heating purposeful heating, melting, quenching, welding, heat treatment, followed by various forms of induction heating equipment. Induction heating has been widely used in metal smelting, heating, heat treatment, and welding technology in metallurgy, national defense, mechanical processing and casting, shipbuilding, aircraft, automobile manufacturing, and other industries. In addition, induction heating has entered people’s family life, such as a microwave oven, induction cooker, water heater, and so on.
Application of induction heating in industrial manufacturing
Application of production technology: it has been widely used in aluminum factory mold heating, leather factory drying furnace heating, injection molding machine barrel heating.
Principle of electromagnetic induction heating
Electromagnetic induction heating is the use of a self-heating and heating conductor caused by high frequency magnetic field generated by the induction current. The principle of magnetic field induction eddy current is that the magnetic field is generated by the current in the coil. The magnetic field in the magnetic metal material will make the metal body produce numerous small eddy currents. The metal material itself heats the metal body at high temperatures to reach the temperature of the object. An AC output device, through the action of an induction coil alternating magnetic field on a metal object in the electromagnetic field, produces a number of closed rotating current objects. Since the electric current has a thermal effect, it produces a large number of endothermic objects. There is also a lag loss, which also causes an object to differ in a certain amount of heat. Therefore, the object will be heated rapidly in a very short time. Generally speaking, the high frequency is used to heat the workpiece, the surface is heated at shallow depth, and the low frequency is used to heat a large metal workpiece, such as the cylinder, with the maximum penetration depth up to 15mm.
Although the principle of electromagnetic induction heating is relatively simple, its practical application still depends on many factors: the use of electrical resistivity and material permeability; Selection of power frequency power supply; The application of electromagnetic induction heating will be affected by the specific operation method.
Characteristics and application fields of electromagnetic heating technology
Induction heating is based on two basic physical phenomena: Faraday’s law of electromagnetic induction and the Joule effect. In the memory area of the alternating magnetic field circuit, the two ends of the circuit will generate induction electromotive force generation circuit closure. It also makes the present principle of induction heating, and also makes the theoretical basis of the induction heating principle.
When the ac current of the induction coil passes through the coil, the AC magnetic field will be generated at the same frequency, and the alternating magnetic field will generate the electromagnetic field E. The induced electromotive force E can be obtained on the metal workpiece according to Maxwell’s electromagnetic equation. Thus, by induction heating, an inductor coil can be transferred to the heating metal, which then converts electrical energy into heat within the metal. The ability of the induction coil and the heated metal not to contact directly through electromagnetic induction.
After years of promotion and popularization, both the electronics industry, business, home are very popular. The three series products of an electromagnetic heating control board, electromagnetic heating controller, and electromagnetic heating control cabinet are mainly used in the following industries and fields:
Injection molding machine, granulator, blow molding machine, wire drawing machine.
Film blowing machine, extruder, vulcanizing machine, printing machine.
Tubing, steam boiler, thermal oil boiler, hot water boiler.
Pharmaceutical heater, heating furnace, plastic dryer, ironing boiler, food heating equipment, paper making equipment, tea equipment.
Commercial induction cooker, household heating device.