Refractory concretes are unshaped, ready-to-use, hydraulic and ceramic materials.
It is possible to distinguish two families :
- Dense refractory bricks
- Insulating refractory bricks
Dense refractory concretes are considered as such when their density is equal to or greater than 1750 Kg/m3 and are intended for installations presenting chemical, mechanical or abrasion risks. Examples: melting furnaces, forge furnaces, cement kilns
As thermal conductivity is connected to density, dense refractory concretes are conductive and therefore not very insulating.
Insulating refractory concretes have a density of 1500Kg/m3 or less after firing. They are primarily used for the construction of enclosures and furnaces not presenting any major mechanical risks. Their first virtues are to limit heat loss. Examples: thermal treatment oven, ceramic furnace.
Insulating refractory concretes are commonly used in the production of moulded parts.