This article will take an in-depth look at infrared ovens.
You will understand more about topics such as:
An infrared oven is an oven that heats objects or cooks food using infrared radiation instead of conventional conduction or convection heating. People can use infrared ovens in commercial kitchens, homes, or industrial settings. Infrared ovens are produced by a variety of companies and frequently designed to serve a variety of functions.
Regardless of the air temperature around them, infrared waves move through the air and release heat energy when they come into contact with a surface. The molecules of an item encountered by an infrared oven are excited by that heat energy and start to vibrate and gain energy (and warm up). Water is particularly well-absorbed through infrared ovens. An infrared oven is distinguished from a convection oven by how it heats food. A convection oven uses a fan to surround and help heat the food. An infrared oven allows you to cook food without heating the surrounding air.
Although microwave ovens are more widely-used than infrared ovens, their operating principles are essentially the same. However, infrared radiation has a larger wavelength and a higher frequency than microwave radiation, which has a shorter wavelength.
Convection ovens typically use more energy than infrared ovens. Infrared ovens are made to heat up quickly, cutting down on the time the oven uses electricity. The smaller size of infrared ovens over convection ovens contributes to their energy efficiency. Infrared ovens are perfect for small kitchens because of their small size.
Since they don't utilize a fan, infrared ovens are quieter than convection ovens.
Although infrared ovens might have prices comparable to convection ovens, infrared ovens are less prevalent than convection ovens. Infrared ovens are nonetheless highly powerful. This increased power is why smaller infrared ovens cost about the same as larger convection ovens.
The principal heat source in infrared ovens is electromagnetic radiation with wavelengths ranging from 780 nm (nanometers) to 1 mm (millimeter), which is invisible to the human eye. Since the beginning of time, infrared radiation has been used to heat objects. The material or food within the oven is the target of these electromagnetic waves. The infrared oven uses reflectors to direct the energy straight to a specific object rather than heating the air around it.
Radiant heat is produced in infrared ovens primarily by converting electrical and gas energy. An infrared oven cooks an object by heating it with shields and reflectors inside the device. The infrared oven's energy is absorbed by the food being cooked. The optimal line of sight between the flat panel heat emitter and the thing to be cooked is maintained because infrared ovens use long-wave infrared beams of electromagnetic energy to heat objects.
Infrared ovens could be a big commercial cooking apparatus, a modest domestic kitchen appliance, or a sizable device used to "cook" industrial goods. Infrared ovens can also do more than just cooking because a light source generates heat. Infrared ovens are used to apply coatings, cure, bake, preheat, and dry materials, among other comparable tasks in commercial and industrial applications.
Infrared heaters heat only individual items within the infrared beams' field of vision. The light that is invisible to our sight produces heat. Individuals can use the heat produced by infrared ovens to warm items that absorb light. Infrared ovens can reach extremely-high temperatures and one must use them properly for maximum effectiveness.
Due to the numerous varied specifications for infrared ovens, it is challenging to make general statements about them. The fuel or energy source is the first factor to consider. As was already stated, infrared ovens can run on electricity, propane, or natural gas and the energy sources one has available is an essential component when selecting an infrared oven. When multiple energy sources are available, one should compare how much electricity, propane, or natural gas will be used during a typical day and the cost of each energy source.
One should look at how voltage (V) and frequency (Hz) are used when looking for an electric model. Additionally, the heat outputs and maximum working temperatures of various ovens vary.
The specifications of the oven, including its filtration controls, wheels, weight, fan, and temperature, must be considered. An oven’s design should also be considered in terms of its efficiency, power source, and space available to house it. Typically, a protective cover for the heating element is required; this cover may be constructed of copper, iron, steel, or brass.
It is important to take temperature management into account when choosing infrared ovens. The controls should be as simple as the operation itself. Consider leaving the unit's temperature at the same setting throughout the day and bringing in and taking out the heated items frequently during a shift. Individuals can accomplish this by using a single setpoint controller with a door switch that turns off the heat and circulation when the door is opened for loading and unloading.
Sometimes larger infrared ovens are needed for continuous use in larger industrial applications. A PLC (programmable controller) temperature-control system and a graphical human-machine interface (HMI) are frequently needed for this application. These programmable controllers fall between these two heating and cooling extremes and will enable the heating cycle to run efficiently by ramping up, holding, cooling down, and shutting off temperatures automatically. This kind of control will also safeguard the operators.
Clients considering an infrared oven must take the rate of temperature rise into account, depending on the weight and makeup of the item to be heated.
The heating oven's size must be large enough to hold the items that must fit within.
In contrast to microwave or ultraviolet radiation, infrared heating does not present any immediate hazard. In addition, the reflectors and shields employed to increase oven efficiency also serve to make infrared ovens safer. However, as a precaution, one should keep away from closely-positioned, high-intensity infrared emitters for an extended period.
Clients must take the amount of money allotted in a budget for an infrared oven into account. Infrared oven prices are frequently similar to convection oven prices, and occasionally they are less expensive. An infrared oven will typically be smaller than a comparable convection oven, saving money on materials and construction expenses.
However, an infrared oven's parts could cost more than those in a convection oven. Electric infrared emitters, for instance, could be more expensive than gas burners. Another important consideration is the capacity one has to manage infrared heating and other heating sources which results in the more effective use of power or gas.
Regular preventive maintenance is necessary for infrared ovens. Examining the emitters and replacing any that have failed are part of maintaining infrared ovens. Users should also clean electric infrared oven reflectors regularly to preserve efficiency. Users must keep the benefits of infrared heating in mind in order to keep the system performing as intended. Buildup in burner orifices, broken emitters, or filthy reflectors will negatively impact the oven's performance.
So keep the following advantages in mind if you're considering an infrared oven. Infrared ovens enable time savings by speeding up the production process and providing quick emitter response. The majority of infrared oven designs minimize the size of the total curing system, and electrically powered systems don't require stacks or venting because no combustion byproducts are produced. Finally, since they produce reliable results, infrared ovens can be adapted to process various items.
Air reflects infrared energy almost completely, and neither absorbs nor scatters it. Infrared radiation is, however, absorbed by water vapor, carbon dioxide, and other greenhouse gases. The amount of energy absorbed by the gas will be minimal at distances of a few feet or less between the emitter and the object absorbing the infrared radiation.
Some infrared ovens use convection heating to assist with their capabilities. An infrared oven, combined with a convection oven, can more effectively dry materials when the process calls for water dry-off.
There are various types of infrared ovens based on their intended applications. If one, for example, requires an infrared oven for cooking food, one should consider buying the oven best-suited for that application. Likewise, one should select an oven that best dries paint on a specific object, if that is the infrared oven’s intended application. The material or objects the oven will work on play a very important role in selecting an infrared oven.
Infrared radiation is best suited to flat surfaces. However, infrared ovens may also efficiently heat more intricate, three-dimensional forms. Rotating objects allows for constant radiation exposure on all sides as they move through an infrared oven. Additionally, an infrared oven can be divided into different heating zones, providing ample cure times to heat a part's inside surfaces.
Electric ovens transmit infrared heat into a component using electricity. These ovens can be made in various shapes and used for almost any heat-treatment operation. For example, annealing, laminating, sintering, curing adhesives, curing powder coatings, and thermal shaping can all be done in electric infrared ovens.
Electric-based infrared heating is the most environmentally-friendly and fossil fuel-efficient method of heating an oven. Electricity also provides the quickest method of heating a component in an infrared oven. The elements in electric infrared ovens can be molded to fit the contour of a workpiece. The magnitude of energy that an object can absorb will be increased as a result.
A gas catalytic infrared pre-gel oven is an infrared oven that frequently operates alongside a convection oven. It is typically employed after the convection oven. A gas catalytic infrared pre-gel oven is designed to enable freshly-applied powder to gel and begin its flowing process as it starts its chemical transformation when heated. Gas catalytic infrared pre-gel ovens are not intended to fully cure the powder, as a convection oven handles this task.
Gas catalytic infrared pre-gel ovens are the most economical and energy-efficient option of infrared ovens. Gas-catalytic infrared heating consumes a great deal less energy than electric infrared heating. These ovens use gas to power their infrared heating and can cure powder coatings on virtually any substrate. Gas-catalytic infrared pre-gel ovens are used for various processes, including curing, drying, thermoforming, temperature boosting, and applying gel powder coatings. The part temperature is raised in gas-catalytic infrared pre-gel ovens without heat or moving air. This ability lessens the possibility of contaminating powder-coated items or having uncured powder fly off.
Pre-gel ovens are appropriate for the following applications:
Infrared convection combination ovens create radiant/convective heating by combining elements of industrial furnace systems and industrial infrared ovens. They accomplish this by combining plug-style recirculation blowers with infrared heating components.
These systems combine thorough industrial heating and quick electric infrared heating. Additionally, they enable convection drying as well as impingement-assisted consistent heating.
These combined systems provide both convection-assisted heating and drying and the uniformity and air-impingement-assisted heating (that uses an impingement nozzle to blast hot air directly on an object or portion of an object) and drying of the electric infrared oven.
In comparison to radiant-only and convective-only heating, this combination heating method has several features and related advantages:
Radiation quickly and directly delivers heat to the coating in an infrared (IR) curing oven. Direct radiation heat transmission from these ovens quickly warms a coating. To achieve a uniform cure, experts can modify the heat's intensity to account for varying amounts of structure and mass. In addition, because infrared curing ovens can directly heat the coated component, they can cure a coating considerably more quickly than convection ovens.
Several industrial coatings can be cured using infrared (IR) energy as a heat source. Such infrared curing transmits heat directly from an IR emitter, which may provide source temperatures ranging from 500°F to 4,200°F, to the coated part surface. Some energy heats the substrate, while some portion of energy is reflected off the surface and absorbed by the coating. This rapid reaction in the polymer causes curing which occurs in powder coating as soon as the surface is exposed to the emitter. In addition, infrared energy aids the drying process for paints and other coatings.
There are different levels of drying found in infrared ovens based on the wavelength, and resulting energy level, being produced. Bright visible light is also emitted and is a characteristic of high-energy (short wavelength) IR. The coating on an item allows most of the energy to pass through it and be absorbed by its substrate. Therefore, this non-line-of-sight heating for complex part forms makes high-energy IR best-suited for heating a substrate. In addition, high-energy IR allows for the quickest heat-up rate.
Since the coating directly absorbs the energy, medium energy (medium wavelength) IR heating is most-frequently employed for curing. Simple or symmetrical parts work well in an infrared curing oven, and the parts should be rotated regularly for constant exposure. Additionally, the oven’s layout must match the shape of the component being heated. For example, emitters on the ceiling and the floor help heat a cylindrical components' top and bottom.
The long wavelength of low-energy IR is ineffective for curing. Due to ineffective convection heating, a large portion of the energy produced is lost. In addition, when some IR energy does penetrate the coating under low-energy IR, it is absorbed in the surface, which could lead to "skin development" or other flaws.
Infrared composite furnaces are used to preheat and shape carbon composite materials to create components for the aerospace industry. These furnaces perform this task by warming blanks made of carbon composite material which subsequently makes press forming easier.
The medium wave quartz tube heaters in each furnace chamber heat the composite blank from below and above. A stainless steel interior structure in the furnace holds up the composite blank between the bottom and top heating elements during the heating cycle.
The furnace stack system typically consists of PID (proportional-integral-derivative) temperature controls, factory mutually-accepted-over-temperature-limit controls, and independent silicon-controlled rectifier control of top and bottom medium wave heaters. Cooling fans are used to cool the ends and sides of the furnace structure's elements. Optical temperature sensors are included to measure a blank’s temperature before it is taken out of the furnace and put into the forming press. All heater elements are replaceable and accessible from the furnace's exterior.
Infrared ovens can be developed for practically any industrial application where enclosed heat is required. Infrared radiation is frequently utilized in coating applications as an accelerator, preheating, or gel application procedure, but it is also a great option for fully curing coatings. Besides the applications mentioned in greater detail below, lamination, sintering, drying, dewatering, and annealing are other thermal processes for which infrared heating ovens can be used.
After electrostatically applying powder to a product, infrared ovens heat the coated pieces to completely cure the powder coating and produce a hard, long-lasting powder finish. By exposing the coating to electromagnetic energy, infrared ovens cure materials.
It is optional to heat an item’s core completely during this method of curing because this heating process does not rely on warming the surrounding air. Since an infrared oven is smaller, less space is needed for exhaust piping over other ovens. The IR curing oven is also quicker and may also reduce exposure to particles when compared to a convection oven environment.
Drying and moisture management are crucial steps in many manufacturing processes. Applications for drying and dehydrating are configured for infrared ovens. Infrared ovens are becoming more prevalent due to the temperature uniformity they provide. Applications for dehydrating are often used in the chemical, pharmaceutical, and industrial food sectors.
Infrared ovens are used in the automobile industry and elsewhere to loosen (relax) fabric, drain moisture, and de-wrinkle vinyl, cloth, and leather due to their capacity to direct heat to designated areas. During this procedure, heat may be directed to relax trim before being applied. Typically, infrared ovens are used in the automobile industry to remove excessive wrinkles and potential chatter (vibrations) caused by improperly sewn seats.
Heat shrinking is done in infrared ovens. This procedure involves insulating, sealing, wrapping, and encasing wiring in tubing sleeves to shield it from the elements. When heat is given to the wiring, the sleeves respond by contracting. Heat shrinking has several uses, particularly in the encasing of brake, steering, and air conditioning lines in automobiles.
Among their many other uses, infrared warming/heating ovens are often used in automotive assembly lines to warm wire harnesses before they are installed in a vehicle.
The varnishes and paints applied to wood and wood veneers are frequently cured in infrared ovens. Infrared ovens are also used to remove moisture from wood sheets and other wood goods. In regards to wood-finishing applications, infrared ovens are typically used with curing, drying, dehydrating, flash-off (recoating), and boosting (eliminating weak, hollow spots) processes.
Adding heat and raising a product's temperature just below the critical range can release stress from pressure accumulated during earlier procedures like welding.
Sterilization applications are most frequently employed in the pharmaceutical and healthcare sectors. Sterilization is achieved by subjecting dangerous contaminants like fungi and bacteria to high temperatures, thereby killing them. Batch ovens are normally used for sterilization due to their contained processing chambers. However, infrared ovens have also been used to sterilize items like bottles.
Figure 12: Sterilizing Oven
Like microwave ovens, infrared radiation is used in infrared ovens to permeate food. In contrast to conventional cooking methods, where heat must move from outside the food toward the center, radiation starts cooking the food inside more quickly by starting at the center and working outward. According to recent studies on infrared radiation, food heated through infrared radiation won't have its chemical structure altered, making it safe for human usage and ingestion. Due to its inherent benefits over traditional heating systems, infrared radiation is increasingly used in food processing. Food products have been dried, baked, roasted, blanched, pasteurized, and sterilized using infrared heating.
Infrared ovens offer incredibly quick responses. Due to its low thermal mass, the infrared element offers excellent control over temperature levels and heat output. It is a fact that electric infrared radiation can complete some heating processes in a matter of seconds. Convection heating is slower than infrared heating since infrared systems do not directly rely on fossil fuels as a heat source. Since the source temperature of an electric infrared heating element is high, the high thermal transfer allows objects to be heated quickly.
Up to 88% of the electrical energy input is transformed into radiant heat energy with an infrared oven. As a result of this high efficiency, more heat is transferred to an object.
Infrared ovens employ an efficient and ecologically-friendly electric heat source. These ovens have a clean heat source that doesn't emit any pollutants. Compared to convection heating, an infrared oven performs so much quicker that fewer pollutants result during the heating of an object. Industrial ovens are powered by a flameless process that oxidizes fossil fuels below their temperature of combustion which prevents the burning of fossil fuels. This process also greatly reduces the amount of gas or propane required to heat an object when compared to convection heating. As a result, carbon dioxide emissions are decreased. In addition, the gas-catalytic infrared emitter produces a very small amount of carbon monoxide.
Infrared ovens have fewer components than other ovens. With fewer components, there are fewer maintenance concerns. In addition, the heating circuit itself requires less maintenance due to the absence of moving parts.
The operation of an infrared oven is relatively quiet because it doesn't require a lot of airflow.
Utilizing infrared ovens also has other significant benefits, including easier heat regulation. A convection oven is essentially a hot air box, its conveyor, pieces, and the air inside the oven must all meet the oven's predetermined working temperature. With a decently-designed convection oven, its shutdown function can offer some temperature control. However, this process results in a delayed response and provides little control. Electric infrared oven systems allow for precise temperature control to match the needs of a process. In addition, infrared ovens have a higher level of control due to zonal heating they provide.
Infrared ovens provide zonal heating. Zonal heating allows heat to be focused and adjusted to the level of heat required for a specific process or component. Zoning is an option for all infrared radiation ovens. The response time might vary from a few minutes to instantaneous, depending on the construction style. Thanks to a furnace's zoning, users can generate various heating levels depending on the part or load. The warmth can be regulated from front to back, top to bottom, or even down to the individual heater. Zonal heating gives you more control over a job and can increase job efficiency because you can tailor the heat source to the particular needs of an object. Infrared ovens can be configured to penetrate or heat a product from the inside out as needed by adjusting their ideal output wavelength.
Infrared heating provides better temperature uniformity than convection heating due to its ability to target specific areas with energy.
It has been established that infrared ovens are the least expensive form of heating, with energy savings of up to 50%–65% compared to other traditional oven systems.
Manufacturing enterprises can reduce the amount of space needed for heating equipment thanks to infrared heating ovens. The reduced size of infrared ovens, which comes from using fewer parts in their construction, allows them to fit into smaller spaces. In addition, many thermal processes take less time to complete when using infrared radiation, which can result in cheaper production and labor expenses overall.
Infrared ovens' coils can become dangerously hot and should not be used near children or animals.
Infrared ovens begin to emit heat as soon as they are turned on, but they also stop emitting heat as soon as they are switched off. This immediate heat loss is due to the fact that infrared objects do not heat the air surrounding a heated object. A conventional oven, in contrast, will keep providing heat after the appliance has been turned off since it takes time for the heated air to cool.
Long-term exposure to infrared radiation can harm the eyes of those who are exposed to it. People cannot detect this energy source as a potentially harmful light source since it does not fall within their visible light spectrum. As a result, the cornea and lens of the eye can be harmed by prolonged exposure to this strong electromagnetic radiation. Therefore, goggles are required for anyone working close to an industrial infrared oven.
High amounts of infrared radiation can also harm the skin and tissues of people. In addition, long-term exposure to high temperatures can harm skin sensors over time. Therefore, one must use safety precautions to prevent skin damage when exposed to prolonged radiation from infrared ovens. Proper loading and unloading procedures for infrared ovens should also be incorporated as a means to reduce skin exposure.
A conveyor oven is a continuous flow oven; it‘s an oven that is open on opposing sides and has a conveying system running from one end of the oven to the other. Designed like a batch oven, conveyor ovens have the additional benefit of keeping products moving while providing continuous and uniform heat...
A curing oven is thermal processing equipment used by thermal specialists to improve or enhance the strength and durability of materials. Many factory processes such as baking, drying, heating, cooking, and curing require...
An industrial oven is a device used to create extremely high temperatures to heat treat parts, condition metals, and cure metal coatings. Common functions for industrial ovens include drying, curing, testing, and coating of parts and products...
Industrial ovens are thermal processing machines used as heating chambers for drying, curing, and baking of foods, parts, and components. The main industries that use industrial ovens are chemical and food processing and electronics manufacturing...
A furnace is a direct fired device used to provide heat for industrial processes that require heat in excess of 400° C (752° F). Any industrial application that relies on heat to create a reaction or heat materials for production uses an industrial furnace...
A normal function of an industrial furnace is to heat treat metals for annealing, tempering, or carburizing and pre-treat materials for forging. Though metal is a common material to be treated using an industrial furnace, other materials are also...