Ceramic kilns are classified according to various criteria and there are a lot of them. If you need to buy such a device or make it yourself, you will have to understand these subtleties. It should be noted right away that the easiest way to make it will be an air-type muffle furnace.
Type of furnace by heater location
The main classification is according to the location of the heating elements. There are only two types. This can be a muffle or chamber furnace. If the device is made in the form of the first structure, then the heating elements will be located around the chamber of fire-resistant material (muffle). As for the chamber type, in this case the heating element will be located inside the chamber itself.
A distinctive feature of chamber species is that they have less heat loss, since the heat from the element is not spent on overcoming refractory. However, in some cases, the use of a muffle layer is simply necessary, since it will provide high performance. Chamber furnaces are characterized by the fact that there are no obstacles between the ceramic product and the heat source, which means that the heating temperature will be much higher. Most often, such equipment is professional.
Views by type of load
The general classification on this basis divides all aggregates into only two types - frontal and vertical. A more detailed description is as follows:
- horizontal devices are loaded from the front through the camera;
- there are tubular devices, they are also periodically called circular, they have a vertical loading method, and they are also designed for firing art-type ceramics, this is facilitated by a more uniform distribution of heat;
- bell-shaped designs are also loaded from above, but at the same time they are designed for larger-sized products.
Another important parameter is the type of filler. Chamber furnaces and muffle ovens are divided into three types for this class.
- the first class is general-purpose, and the camera is filled with air;
- the second type is filled with vacuum;
- the third type is chambers with a gaseous medium inside, and they differ in that the heating also occurs in the special atmosphere created by these gases.
Temperature characteristics
Another very important parameter for a ceramic kiln is temperature. It completely depends on such things as the design of the equipment and its purpose. The hottest furnaces are characterized by temperatures up to 1400-1800 ° C. The result of work in such furnaces is usually ceramic with a color from white to orange. If the furnace is at a lower temperature, then as a result, you can get products from clay, the shades of which will be from dark red to burgundy. The most low-power ceramic kilns are characterized by a temperature of less than 500 ° C. Such devices are capable of producing ceramic products with shades of only red.
Materials for assembly
A ceramics kiln can be made by yourself if you know the brief instructions, as well as have all the necessary materials for assembly. It is also worth saying that the muffle furnace can be with a gas and electric heater. Gas will even be several times cheaper due to the fact that you have to spend less on fuel, but according to the law it is impossible to make such devices with your own hands. In addition, from a technical point of view, a gas furnace is extremely difficult to manufacture.
In order to successfully do-it-yourself assembly of an air-type muffle furnace with an electric heater, you will need:
- angle grinder and one or two circles;
- welding and electrodes for it;
- locksmith tools;
- another important element is a 2 mm thick nichrome wire.
From the materials you will need the following list:
- case from an old steel-type oven or steel sheets with a thickness of 2.5 mm;
- corners, fittings;
- basalt cotton wool for thermal insulation;
- fireclay brick of refractory type and brick with the same properties;
- silicone sealant.
Highlights
The instructions for the muffle furnace are quite large, it is difficult to describe the whole process, but it is worth highlighting the main points.
The best option would be to have a casing from an old steel oven on hand, since it already has everything you need to become an acceptable casing for an oven. There is all the thermal insulation, it will only be necessary to get rid of unnecessary plastic elements, if any. Next up is the heating element, which is the key.
From it will be the heating temperature, which means the quality of ceramic products. A previously prepared nichrome wire with a minimum thickness of 1.5-2 mm will act as such an element. Then follows the process of arranging the thermal insulation of the furnace. To do this, the body must be covered with fireclay chamotte brick. From above it is necessary to overlay the entire structure with basalt cotton wool.
The price of a ceramic kiln starts from 40,000 rubles and can reach up to 700,000 rubles.