A refractory brick is a block of refractory ceramic material used in lining furnaces, kilns, fireboxes, and fireplaces.A refractory brick that can withstand high temperatures, used to line flues, stacks, furnaces, and fireplaces. In general, such bricks have high melting points that range from about 2,800°F (1.540°C) for fireclay to 4,000°F (2,200°C).
The main specification of refractory bricks is: Refractoriness, Refractoriness under load, Linear changes after reheating, apparent porosity, compressive strength, Bulk density, thermal shock resistance etc. But In Japan, the main specification is in 4 items: Physical property, Chemical property, Mechanical property and Heat property etc.
There are so many kinds of refractory bricks which are used widely. The main methods of classification is followed:
a. Base on Chemical materials: Fireclay brick, High alumina brick, Silica (silicon) bricks, Aluminium silicate bricks, Magnesia bricks, Magnesia chrome brick, Carbon block, etc.
b. Base on Refractoriness: Normal duty refractory brick, Refractoriness is 1580℃~1770℃; High duty refractory brick: Refractoriness is 1770℃~2000℃; Super duty refractory brick: Refractoriness is above 2000℃.
c. Base on process: Pressing refractory brick; Casting refractory brick; Plastic molding refractory brick; Extrusion processing refractory brick; etc.
d. Base on heat treatment: Burning refractory brick; none burning refractory brick; fused refractory brick.
e. Base on Size and Shape: Standard size refractory brick; Normal refractory brick, Special shape refractory brick.
f. Base on usage: Steel making line; Ceramic line, Power plant; Oil and chemical line; etc .