Introduction to Infrared Process Heating
Infrared energy is the most basic form of heat that find applications in various manufacturing processes. For instance, such as infrared ovens are used for drying and heating.
We are all confronted with energy conservation. Can infrared help avoid wasting energy? It can, provided we know how to use it efficiently.
Essentially, infrared is an electromagnetic phenomenon, which is measured in wavelengths (microns). Electromagnetic energy particles attack the surface of materials to be processed after which conduction takes over.
To use infrared successfully, we have to understand this reaction. Most metals act as a good heat conductor. In many cases, however, the conductivity is less than desired resulting in heat absorption and retardation.
Some of the materials may work as an insulator, which prevents the penetration of heat. In this case, the infrared energy must be applied from two sides. One major advantage is the fact that heating tunnels or structures having infrared heat do not require heavy insulation as is necessary in convection ovens.
However, shields on the sides may be needed to prevent drafts.There are infrared heaters made of different materials and configurations, which provide cost-effective heating.
Casso-Solar is a well-known infrared equipment manufacturer and offers a variety of infrared heaters across industries. We also offer customized designs and fabrication of industrial infrared equipment.
Choosing Infrared systems
Basic mistakes in choosing the wrong radiant heater can render such an installation to be inefficient, and costly to operate and maintain. Therefore, it is necessary to find out how infrared actually works.
Infrared radiation is fundamentally electromagnetic energy. This measurable energy can be divided into roughly three types of density:
- Short-wave or very high density radiation beginning with 1.2 microns of usable energy and ending around 2.3 microns
- Medium-wave around 2.5 microns to medium density to around 3.8 microns
- Low-density long wave or far-infrared around 3.8 to 6
Beyond long wave, infrared should not be used because of inefficient radiation resulting in low temperatures. Infrared energy is a surface phenomenon. For example, processing foam is a poor conductor of radiant energy.
Even thin foam should not be radiated from only one side because one surface will be rapidly heated while air or agents trapped in the material act as insulators, thus slowing down heat penetration considerably.
Also, if the surface is shiny, such as aluminum, it may reflect the infrared and bounce it back and forth. This also delays heating. Objects or materials that readily absorb energy usually give satisfactory results.
But this type of application is only a part of where we can apply infrared emission. We can also achieve satisfactory results by combining radiant emission and air flow. In some cases, it is necessary to avoid surface hardening, which causes bubbles underneath a dried coat.
Combining radiant heat and air works well; however, the air must be applied without cooling the radiant heater; otherwise, energy consumption will increase considerably.
Wavelength and Temperature
The wavelength of the radiation is shorter at higher temperatures or vice-versa. Which temperature/micron level is required to process a product economically? That depends on what is being processed and at what speed. Basically, any product has its own inherent reaction to infrared. This is called "heat absorption factor."
Each type of material can be categorized in a certain wavelength and that can be translated into degrees of temperature. It’s always advisable to consult a specialist of infrared radiation applications to help you find the proper way to apply infrared energy.
In many cases, the peak of absorption will be flattened. This is because the material to be heat treated will have not only one basic type, but additives which contribute to shift the peak to the shorter or longer absorption factor.
In all cases, infrared is a hotter energy source than convection heat. Infrared heat is always applied directly to materials. The exposure of the material to this direct heat source has to be timed appropriately to avoid overheating and damage. This is where infrared ovens can help. They are designed to control the amount of heat and timing.
Replace Your Current System
Can your current heating system be replaced by one which uses radiant infrared energy, and under which circumstances can it be done? If the material lends itself to be processed by infrared radiation economically, which means a drastic reduction of energy and higher speed of production, we must consider this alternative now.
This excludes heavy bulk of any type, and materials, which by nature, have to be transformed into the required state by slow heat processing. When a heat radiator glows at any color, dark red to white hot, it means the radiation has already reached at least 1185 degrees F and may go up to high temperatures, according to the color of the element.
We cannot make use of this heat just by exposing materials to it even if it has the proper emission value unless it is timed. Ideally, one should opt for a considerably faster method of heat processing with a relatively low energy requirement, using the right system that emits the required wavelength
Being a reliable industrial infrared equipment manufacturer in based the US, we are committed to providing superior quality products. In case you have requirements for infrared heating systems, industrial infrared ovens, please feel free to contact us today.
For tips on how to select an infrared heater for your application, please see our blog post on that topic.