Application of the hottest infrared radiator in th

  • Detail

The application of infrared radiators in thermoplastic molding process

based on the current thermoplastic molding process, this paper compares and analyzes several kinds of infrared radiators commonly used in thermoplastic molding machines, so that readers can have a more comprehensive understanding of the development trend of infrared radiators in thermoplastic molding process

requirements of thermoforming machine for infrared radiator

what thermoforming machine needs is a heating area matching the size of the formed sheet, and each independent infrared radiator is the basic composition of this area. The radiation characteristic of the infrared radiator is that the radiation rays are scattered, which not only heats the materials in the direct direction, but also has radiation effects in all directions. Common infrared radiators include ceramic plate infrared radiator (plate), halogen quartz tube (tube) and carbon medium wave radiator (tube). The experiment shows that compared with the tubular infrared radiator, the plate-shaped infrared radiator will be a milestone in the history of aerogel gel material production, and has better radiation effect

plastic materials are heat sensitive materials, and the temperature will affect the forming process of materials and even the quality of finished products within a certain range. Usually, the thermoforming machine adopts the method of real-time temperature measurement to monitor the infrared radiator in real time (it can also control the temperature of heated objects). Therefore, the integration of temperature sensor in infrared radiator is the priority of thermoplastic molding machine

In the thermoplastic molding machine, the heating area is composed of multiple monomer radiation elements. If a component stops heating during the production process, the temperature of this component will be significantly reduced. According to the data of Germany Illig company, a famous manufacturer of thermoplastic molding machine, when the heating area is set to 600 ℃, the component that stops heating and the function display of prospector sebco will be reduced to 120 ℃. This will seriously affect the normal operation of the thermoplastic molding machine. Therefore, the radiator with long service life is one of the requirements for the selection of thermoplastic molding machine. As we know, the service life of the infrared radiator largely depends on the working temperature of its coil. If the temperature is high, the service life of the anchor bolt is short, and if the temperature is low, the service life is long. Therefore, choosing the infrared radiator with low coil temperature during normal operation can ensure the long-term stable operation of the thermoplastic forming machine. Figure 1 shows the radiation area of a single radiator in the radiation system

different types of infrared radiators

ceramic radiators

take elstein ceramic infrared radiators in Germany as an example. Figure 2 shows the structure of the ceramic infrared radiator. The heating wire 1 is embedded in the ceramic body 3. It is hollow inside and embedded with thermal insulation material 2, which reduces daily consumption by about 18% compared with solid ceramic radiator

when the ceramic radiator is within 650 ℃, the surface does not emit light, which is commonly known as dark infrared

the ceramic radiator has a built-in thermocouple temperature sensor, which can monitor the temperature change of the ceramic body and carry out feedback control, which is easy to realize the control of power (temperature)

silicon carbide radiator

Figure 3 is the structural diagram of the silicon carbide radiator. Nickel chromium alloy is used as the heating wire 1, which is installed in the silicon carbide tube and connected through the head and tail of the tube. When the power is turned on, the heating wire will heat up in seconds and emit a reddish light through the tube

the infrared ray of the silicon carbide radiator mainly comes from the infrared ray emitted by the heat absorbed by the silicon carbide tube. Therefore, when the tube is red seconds after power on, it does not mean that the silicon carbide radiator has reached the set temperature. It still needs a period of warm-up time

due to the structure, the silicon carbide radiator cannot have a built-in thermocouple temperature sensor, but must have an external temperature sensor for temperature monitoring

halogen quartz radiator

Figure 4 is the structural diagram of halogen quartz radiator, which places a tungsten filament 1 in a quartz tube 2 filled with halogen gas. When powered on, it will soon glow into a lamp, so its peak wavelength band is very narrow

visible light is an electromagnetic wave without heat, so part of the energy of halogen quartz radiator cannot be converted into heat and lost. In addition, due to the length of the radiation wave of this infrared radiator, the radiation wave has strong penetrability. Therefore, this infrared radiator is not suitable for the molding of thin plastic sheets

halogen quartz radiator can't have built-in thermocouple temperature sensor, so it needs external temperature sensor for temperature monitoring

gas radiator

Figure 5 is the structure diagram of the gas radiator, which is preheated by the electric starting element 6, ignites the internal gas 5, and heats the panel 7 by gas combustion

the surface temperature of the gas radiator can reach 600 ℃, and the heating performance is equivalent to that of the ceramic radiator, but it cannot be used in a closed environment due to the need for combustion

thermoplastic molding is a complex process, which involves the physical and chemical properties of plastic sheets, the heating characteristics of heaters, electrical control and the coordination of mechanical parts. With the continuous improvement of the requirements for the quality of finished products, the requirements for temperature control and heating uniformity in the molding process are also continuously improved; At the same time, as the proportion of energy consumption in the cost of manufacturers continues to rise, whether to save energy is also an important factor for manufacturers to consider. Therefore, using infrared radiators with high stability, long service life, good uniformity and excellent energy-saving performance is the development trend of thermoplastic molding process

reference: illig-thermoforming-a practical guide, plastic molding heating specification (end)

Copyright © 2011 JIN SHI