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Some Basic Knowledge About Electromagnetic heaters (II)

The working principle of electromagnetic heater is: 220V or 380V alternating current, rectified into direct current, and then filtered direct current. IGBT or thyristor is used to turn DC into AC to generate high-frequency magnetic field lines in the induction coil. Eddy currents are generated on the surface of the conductor workpiece in the induction coil, relying on the self-generated internal resistance to generate heat.


The frequency converter is the core component of the high-frequency electromagnetic heater. It is a power control device that uses the on-off effect of power semiconductor devices to convert power frequency power to another frequency. At present, the frequency converter used mainly adopts AC-DC-AC mode, first converting the power frequency AC power supply into DC power supply through the rectifier, and then converting the DC power supply into AC power supply that can be controlled by frequency and voltage to supply the motor.


The heating ring heating method is to transfer heat to the barrel by contact conduction. Only the heat close to the inside of the barrel surface can be transferred to the barrel, so that most of the heat on the outside is lost to the air, there is a loss of heat conduction, and the ambient temperature rises. In addition, resistance wire heating also has a disadvantage that the power density is low, and it cannot be adapted in some heating occasions that require higher temperatures. Electromagnetic heating technology is through the principle of electromagnetic induction to make the metal barrel itself heat, and can be wrapped in a certain thickness of thermal insulation material outside the barrel according to the specific situation, which greatly reduces the heat loss, improves the thermal efficiency, so the power saving effect is very significant, up to 30% ~ 75%. Because the electromagnetic heating ring itself does not generate heat, and is made of insulating materials and high-temperature cables, there is no problem that the resistance wire of the original heating ring oxidizes at high temperature and shortens the service life. It has the advantages of long service life, fast heating rate, and no need for maintenance, which reduces maintenance time and costs. Now it has been used by the majority of plastic products enterprises, greatly reducing the production cost of enterprises.


The plastic extrusion machinery made by Laizhou Kaihui Machinery Co., Ltd. is suitable for different types of electric heater. We can recommend according to customer’s need. Welcome to contact with us to get more information

Some Basic Knowledge About Electromagnetic heaters

Post time: Mar-07-2023