Fireclay plates and other refractory materials - application of
All chamotte refractories are characterized by their mechanical strength and ability to provide long-term resistance to various loads in conditions of increased heat resistance. One of the most remarkable properties of refractories is heat resistance, i.e.resistance to multiple temperature changes with high speed with constant external parameters: volume, shape and size.
The most famous refractories are chamotte bricks, without which today there are inconceivable heating stoves and fireplaces, kitchen fires, as well as special ovens for burning porcelain, melting glass and metal. In them, fireclay bricks are used in the furnace part, i.e.in a place of direct contact with fire, where the temperature sometimes reaches 1650 degrees Celsius.
Chamotte brick is produced by firing a mixture of powder-chamotte( up to 70%) and refractory clay. Often instead of chamotte, quartz or graphite powder is used. This depends on where the brick is supposed to be used, from the temperature regime and the chemical characteristics of the object.
Fireclay products - distinctive characteristics of
It is easy to determine visually the belonging of a brick to a refractory class - it is given out by a granular structure and yellow-sand color. And also the marking on the case - the letter "Ш".The quality brick does not crumble when crushed, but splits into large enough pieces.
In addition, when tapping on it, a metallic sound is clearly heard, while in a badly baked brick it is deaf. Bad firing is the cause of a very unpleasant phenomenon - such a fireclay product absorbs moisture perfectly, as a result of which the brick loses a significant part of its original properties.
A stove made of such a brick, at best, will not perform its functions of heating and maintaining heat, at worst - it just collapses.
As mentioned above, fireproof brick is designed for fencing against fire and high temperature, it is like a kind of protective layer, protecting the design of the furnace from the fire raging in the furnace. Proceeding from this, the requirements are formulated, which must be answered by fireclay bricks:
- heat resistance, i.e.property without any harm to withstand long-term heating up to 1650 degrees Celsius;
- low thermal conductivity, in other words, it must reliably keep heat inside the furnace, preventing its losses;
- increased heat resistance - the ability to withstand the maximum number of cycles of rapid heating and cooling without loss of strength.
Fireclay refractories and other application of chamotte
Chamotte plates occupy a leading place among refractory products, from them heat-accumulating elements of furnace bodies and fireplaces are made, which is difficult or even impossible to make of bricks. This, for example, can be elements of local forms.
Unlike brick slabs, you can easily cut into strips of the right size and out of them lay out, for example, the semicircular surface of the lining. Another difference from bricks is that the slabs are essentially chamotte fibrous products, i.e.not heat-shielding, but heat-accumulating elements, they accumulate heat in the process of burning and after stopping the furnace give it to the environment.
It's possible to talk indefinitely for a long time about where the use of fireclay finds. Thus, in metallurgy, chamotte crucibles are widely used, intended for melting of various metals, and the fireclay pipe is often used as a chimney resistant to acids and temperature changes.