Industrial Ovens and their different uses
We all know the type of ovens that we use at home for our everyday use, but did you ever wonder what is an industrial oven?
Industrial ovens are used to create extremely high temperatures to heat treat parts, condition metals, and cure metal coatings. Their common functions include drying, curing, we know industrial ovens for baking, testing, and coating of parts or products. The type of treatment describes the property changes of a product when it is heated, such as dried, baked, or dehydrated.
Use-wise there are three types of industrial ovens, unique in their construction, product handling, and flexibility. Laboratory ovens are used to test samples during product development or complete light duty production of small parts, industrial batch ones process large quantities of products and come in both, big or small sizes, while conveyor ovens are made strictly for automated production, designed to fit into a specific manufacturing process.
The type and description of an industrial oven also depends on how it is used. Curing ovens, for example, create a chemical reaction between a powder and metallic surfaces, while drying ovens remove moisture from raw materials. Other industrial ovens prepare metals for processing, melt them together, remove contaminants etc.
When describing how an industrial oven works, the first thing to be considered is the type of fuel it uses. It can be hot water, direct and indirect gas, ultraviolet light, steam, or electricity. Electrically heated ovens have quick heat-up times, precise temperature controls, and reasonable price. Gas industrial ovens, on the other hand, are more expensive to build, but cheaper to run. They heat up quicker and maintain temperatures longer than electric or infrared ones. Their fuel is natural or propane gas. They come handy by curing coatings on steel and assisting in the production of automotive parts such as brake pads and linings.
Ceramics are broadly defined as inorganic, non-metallic materials that exhibit high strength and hardness, high melting temperatures, chemical inertness, and low thermal and electrical conductivity, but also display brittleness and sensitivity to flaws.
As practical materials, they have a history almost as old as the human race. Traditional ceramic products, made from common, naturally occurring minerals such as clay and sand, have long been the object of the potter, the brickmaker, and the glazier, while modern advanced ones are often produced under exacting conditions, demand the skills of the chemist, the physicist, or an engineer and are made into a wide range of industrial products, from common floor tile to nuclear fuel pellets.
Ceramics generally start with a clay-based material dug from the ground, mixed with water and other materials, squashed into shape and fired at high temperature in a large industrial oven called a kiln - the four basic processes, that have been used thousands of years. The very word "ceramic" originally comes from Sanskrit and means "to burn."
Common clay is mostly used for bricks, cement, and aggregate, with kaolin we make porcelain and glossy paper, bentonite has a variety of industrial uses and is also found in certain household products, ball clay is highly prized for its use in sanitaryware etc. Each one of them also has numerous different grades and qualities, so it's probably more accurate to refer to them in the plural. It is most common that in a single clay mine, different grades of clay will be simultaneously excavated from different areas and kept separate (or blended in various ways) for different end uses.
Heat treatment of ceramics
Industrial kilns (ovens) have been a fundamental part in ceramic making for thousands of years, supplying raw compounds such as lime (CaO) and finished products like pottery through high-temperature, kiln-firing processes. Mankind has been using them since approximately 6000BC. Early pit-firing techniques were superseded by the utilization of a thermally insulated firebox with an aperture for stoking fuels, and a self-contained chamber for wares, with a chimney to improve the kiln’s draw. This ingenious yet rudimentary formation of an industrial kiln was broadly utilized in ancient Greece and were responsible for the varying oxidation of iron (Fe) concentrations in the pottery, resulting in the famous red-black colouring of ancient Greek pottery. The Roman Empire expanded upon the established methods of Greek industrial kiln manufacturing processes by equipping open kilns with air-flow piping, designed to redirect smoke away from fired products.
Electric industrial kilns vastly improved the firing process as they replaced wood or coal, with heating elements such as metallic wires or coils which generated radiant heat using electricity. There is a wide spectrum of electric industrial kiln types and designs available for modern manufacturing or materials processes. Modern ceramic heaters are equipped with integrated insulation that optimizes heat distribution throughout a heating chamber. These industrial kilns are commonly applied for hardening processes such as annealing, tempering, and calcination and are required to operate at temperatures of up to 1300°C, which depends upon the specific application. They also offer low oxidation properties for reaction processes.