Basic Fire Bricks - RS Kiln Refractory Bricks

Basic Fire Bricks Description

Basic fire bricks or alkaline fire bricks is the kind of refractory bricks, which’s main chemical composition is calcia and magnesia. Basic fire bricks are alkali resistant bricks can be used in alkaline working condition. Generally speaking, basic fire bricks can be divided into 7 groups: magnesia bricks, magnesia chrome bricks, chrome magnesia bricks, chrome bricks, forsterite bricks and dolomite bricks.

magnesia-chrome brick

magnesia spinel bricks

magnesia brick

Basic Fire Bricks Main Components

Group	Name	MgO %	CaO %	SiO2 %	Al2O3 %	CrO 2%
MgO based	Magnesia brick	≥87	＜3.5
	Magnesia silica brick	≥82		5~11
	Magnesia calcia brick	80~87	6~10
Magnesia spinel based	Magnesia alumina brick	≥80			5~10
	Magnesia chrome brick	55~80				8~20
	Chrome magnesia brick	25~55				15~30
	Chrome brick	≤25				＞25
Dolomite based	Dolomite brick	30~42	40~60
	Magnesia dolomite brick	50~80	10~40
	Stable dolomite brick	35~65	15~40
Olivine based	Forsterite brick	35~55	25~60
Lime based	Calcia brick	＞70

Basic fire bricks properties

Corrosion resistance

Basic fire brick has good corrosion resistance to metal smelting slag, cement clinker, glass kiln production material and ash. Different media will have corresponding affection to basic bricks. Under strong base conditions, such as cement kiln sintering zone, cement clinker corrosion resistance ability of basic fire bricks is: Magnesia dolomite brick>magnesia chrome brick>magnesia spinel brick. For converter and electric furnace lining, Magnesia fire bricks with higher CaO/SiO2 ratio have better basic corrosion resistance than those with lower CaO/SiO2 ratio. For glass kiln regenerative chamber checker, the magnesia bricks with lower CaO/SiO2 ratio have better performance. For heavy nonferrous metal smelting furnaces, the FeO-SiO2 slag corrosion resistance ability is: magnesia chrome brick> magnesia brick>magnesia spinel brick>magnesia dolomite brick.

High temperature performance

The refractoriness of basic fire bricks are above 2000℃, is higher than other refractory bricks. The rupture under load temperature, high temperature rupture strength, high temperature volume stability and high temperature creep property of basic refractory bricks is better if the density is higher and the impurity content is lower. Ordinary basic refractory bricks have a rupture under load temperature about 1550~1600℃. The rupture under load temperature of high grade alkaline refractory bricks such as magnesia dolomite bricks, magnesia spinel bricks, high purity magnesia bricks and direct bonded magnesia chrome bricks is above 1700℃, for Semi-re-bonded and re-bonded magnesia chrome bricks, it can reach to 1750~1800℃.

The thermal expansion rate of basic refractory bricks is higher than other fire bricks. MgO based basic refractory bricks have similar thermal expansion rate. At 1600℃, the linear expansion rate of magnesia bricks is the largest, about 2%. High grade magnesia chrome bricks have the smallest linear expansion rate, about 1.6%, other basic refractory bricks is between 1.6% and 2%.

Thermal shock resistance of basic refractory bricks is not as good as clay bricks and high alumina bricks. Thermal shock resistance ability of alkaline refractory bricks is: magnesia spinel bricks>magnesia chrome bricks>magnesia dolomite bricks> magnesia bricks.

Hydration resistance

Compared with high alumina bricks, clay bricks and silica bricks, basic fire bricks has the worst hydration resistance ability. Among basic refractory bricks, magnesia calcia bricks have the highest hydration tendency, and is in direct proportion to CaO content. So much attention should be paid to hydration problem during the production, storage, delivery, masonry and using of alkaline fire bricks

Refractory Material Professional Manufacturer & Supplier – RS Refractory

Rongsheng kiln refractory manufacturer is a comprehensive enterprise in refractory material industry, high temperature fireproof products cover metallurgy, refractory building materials, electric power, chemical industry, etc. Hot sale products such as ceramic fiber refractory material, refractory bricks, castable, refractory cement, ramming mass and so on are exported to many countries in the world and highly appreciated by customers.

Burnt Magnesite Brick

Burnt magnesite brick refers to alkaline refractory products (basic refractory materials), which are fired with periclase as the main raw material. The load softening temperature of Burnt Magnesite Brick is high, and the corrosion resistance of alkaline...

Magnesia Bricks

Magnesia bricks are usually called sintered magnesia bricks, are kind of basic fire bricks with the largest output and widest applications. According to the MgO content, magnesia bricks can be divided into 3 grades: 90, 95 and 98. The corresponding minimum...

Magnesia Chrome Brick

Magnesia chrome bricks are basic refractory product which’s main crystalline phase is periclase and magnesia chrome spinel. For magnesia chrome brick, the magnesia content range is 55%< MgO <80%, for chrome magnesia brick, magnesia content is b...

Rebonded and Fused Cast MgO-Cr2O3 Bricks

Rebonded and Fused Cast MgO-Cr2O3 Bricks also refers to the Fused Rebonded Magnesia Chrome Bricks. Usually, magnesia chrome bricks made from fused magnesia chrome sand are called rebonded magnesia chrome bricks. While, the refractory bricks partly added...

Rebonded Magnesia Bricks and Chemical Bonded Magnesia Bricks

1. Rebonded Magnesia Bricks Description Rebonded magnesia bricks use fused magnesia sand as raw material, so rebonded magnesia fire bricks are also call fused magnesia bricks. Compared with sintered magnesia sand, fused magnesia sand has higher MgO...