Refractory bricks are made from materials that stay physically and chemically stable in high temperatures.
These are sometimes referred to as firebricks, kiln bricks or fire bricks.
These bricks generally come in two standard sizes.
Bricks made like this are used for the lining of kilns, furnaces, fireplaces and fireboxes.
Your glass fusing kiln most likely contains these porous bricks.
Although they are weaker and not as dense as regular firebricks, they insulate much better.
These types of fire bricks hold up under the quick temperature changes inside the kiln.
There are many companies that manufacture these clay bricks.
On top of being able to withstand high temperatures, these bricks can stand up to objects hitting them in case something goes wrong inside the items they line.
This makes them durable even under duress.
The bricks are made from special clays that are often blended with other materials such as alumina, chromium oxide, silicon carbide and other things.
Over the years, the companies have refined the composition of these bricks to better suit their purpose.
It all depends on what these bricks will be used for, as to the materials included in them.
The right brick needs to be used in a kiln for instance.
The manufacturers do offer suggestions on the use of their bricks.
It is important if you have a glass fusing kiln though, to inspect the bricks contained in it.
Over time, the bricks will break down and begin to crack or have other issues.
Have your kiln repaired, if this occurs, to ensure the proper operation of the kiln.
The inside of your kiln should be cleaned from time to time, because the bricks can get dirty from use.
This keeps the kiln from operating correctly.
Your kiln heats to temperature partially because of the qualities of the clay bricks.
Without the heatproof insulation they provide, your kiln could not retain its heat inside to fire your glass projects.
Of course, the bricks are only one part of your kiln.
There are heating elements and controls that also make your kiln work.
If damaged by glass sticking or other reasons, they can be repaired using a type of kiln cement.
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