The melt-blown process requires a lot of hot air. The compressed air from the air compressor is transported to the air heater for heating after dehumidification and filtration, and then to the melt-blown die assembly. The voltage ratio of input to output is equal to the ratio of coil turns, while the energy remains unchanged. Therefore, the secondary coil generates a large current at low voltage. The principle is that when a thicker metal is in an alternating magnetic field, it will generate current due to electromagnetic induction. In this way, the heat generated by the current flow is absorbed by the metal itself, which will lead to the rapid heating of the metal. The heating and cooling rate block can reach 10 C/S, and the adjustment is fast and stable. There will be no leading and lagging phenomena of the controlled air temperature, which makes the temperature control drift uncertain. It is very suitable for automatic control. Explosion-proof electric heater is generally used in dangerous situations where explosion may occur. Because there are various kinds of flammable and explosive oil, gas and dust in the surrounding environment, once touched by electric spark, explosion will occur. Therefore, in this case, explosion-proof electric heater is needed for heating. The internal control system of electric heater automatically adjusts the output power of electric heater according to the temperature sensor signal of the output port. Rate, so that the medium temperature of the output port is uniform. The internal control system of the electric heater automatically adjusts the output power of the electric heater according to the temperature sensor signal of the output port, so as to make the medium temperature of the output port uniform; if the overtemperature of the heating material causes coking, deterioration and carbonization, the heating element will burn out in serious cases, effectively prolonging the service life of the electric heater. The main explosion-proof measure of the explosion-proof electric heater is to have a flameproof device in the junction box of the heater to eliminate the hidden danger of electric spark detonation. Wind channel electric heater is mainly used for air heating in air duct, which can be divided into three types: low temperature, medium temperature and high temperature. The common structure is that steel plate is used to support the electric heat pipe to reduce the vibration of the electric heat pipe, and the junction box is equipped with overtemperature control device. In addition to over-temperature protection, intermodal transport device is also installed between the fan and heater to ensure that the electric heater must be started after the fan starts, and a differential pressure device is added before and after the heater to prevent fan failure. The gas pressure of the channel heater should not exceed 0.3Kg/cm2 in general. If it needs to exceed the above pressure, the low-temperature type heater should be selected. Heater gas heating temperature does not exceed 160 Medium temperature type does not exceed 260 High temperature type does not exceed 500. The air channel electric heater is used for industrial air duct, air conditioning air duct and air of various industries to heat the air and increase the temperature of the output air. It is usually inserted in the lateral opening of the air duct. According to the working temperature of the duct, it can be divided into low temperature, medium temperature and high temperature, and according to the wind speed in the duct, it can be divided into low wind speed, medium wind speed and high wind speed. This depends on the structure of the heater and the frequency converter, which can change the frequency of AC, thus changing the speed of the motor and achieving the purpose of changing the output power of the motor. The heater does not rotate, nor can it control the heating speed. There are two simple ways: Diode half-wave rectifier is used to change the effective value of AC, and to achieve the goal of changing heating power and speed. Most of them use this method, which has the advantages of simple circuit and easy operation. With a small transformer, transformer, the advantages are adjustable, multiple fault circuit structure is relatively complex, high production costs. |