Heating principles and examples of infrared heating in the plastics sector

The effectiveness of infrared heating depends on the degree of absorption of the object being heated, the higher the absorption rate, the better the

The higher the absorption rate, the better the infrared radiation effect. The absorption rate depends on the type of material being heated, the state of the surface, the wavelength of the infrared

The wavelength of the radiation source, etc. The ratio of the reflected radiation energy to the incident energy is called the reflectance of the material.

The reflectance varies from material to material and from surface to surface. Matter through the ratio of radiant energy and incident energy is called penetration

The penetration rate varies according to the nature and thickness of the material. The effective range of penetration varies from material to material.

The penetration rate of non-transparent materials is usually considered to be zero. Generally, metal crystals are so dense that electromagnetic radiation through the surface can be transmitted within a short distance.

The penetration depth of thermal radiation to metals is on the order of microns, as the electromagnetic radiation through the surface decays rapidly over a very short distance.

In contrast, the molecular structure of non-metallic materials is not very dense, and at room temperature different non-metallic substances have their own characteristic vibration frequency.

Therefore, when the incident electromagnetic wave reaches the interface, the electromagnetic wave is rarely reflected, and it is easier to pass through the interface into the surface

Some of them resonate and become heat, while others that cannot resonate are subject to refraction, scattering and reflection.

As the actual object is not a single structure of simple material, so some of the radiation not absorbed by the surface layer, in the deep

The resonance of other substances will also be absorbed to varying degrees during the entry process. Only when the full thickness is passed

The unabsorbed part of the radiated energy can only be transmitted when the full thickness is passed. Therefore the penetration depth of non-metals is higher than that of metals.

Infrared heating advantages and efficiency, infrared dry heating has developed at an alarming rate in recent years.

The main advantages of infrared drying are as follows

1. penetrating power, can be heated inside and outside at the same time. 2.

2. good thermal efficiency as no heat transfer medium is required

3. localised heating, saving energy. 4.

4. provides a comfortable working environment

5. Save construction costs and space for the furnace, easy to assemble, install and maintain.

6. clean heating process

7. easy temperature control, rapid heating up and high safety

8. low thermal inertia, no need for warming, saving manpower.

Because infrared heating has the above advantages, it is possible to obtain high efficiency and uniformity of heating.

Examples of infrared applications in plastics

Different wavelengths of infrared have different characteristics and correspond to different processing objects. Short-wave infrared is characterised by high penetration and high energy output, which is ideal for thick sheets, resins and other materials that require a short and rapid temperature rise. Medium wave infrared emitters are characterised by moderate penetration and a spectrum that is particularly consistent with the absorption spectrum of water, and are therefore widely used in surface treatment, drying and other processing processes.

1、PVC processing. Infrared radiation is commonly used in PVC processing in the pre-heating of the ginning.

2、Film stretching. Heraeus infrared products are widely used in film stretching (e.g. bi-directional stretching, blown film, etc.) equipment.

3. Plastic welding. Infrared welding avoids many of the defects and drawbacks of contact traditional welding heating methods (e.g. hot plate welding).

4、Surface ink printing and drying. Both to ensure rapid and uniform drying effect, but not damage the substrate - the advantages of infrared heating, especially suitable for plastic surface ink printing and drying

we can customize all type of IR lamps for replacement , just tell us length, power, voltage and quantity . please contact us before purchasing

For more information, contact us today!