Refractory balls for hot air furnace

1、High-alumina refractory balls

Al2O3 mass fraction greater than 45%, alumina or aluminosilicate based refractory material is called high alumina refractory material. General high alumina refractory ball refractoriness of not less than 1750-1790 ℃, the load softening temperature is not less than 1400-1530 ℃. When the higher the Al2O3 content of the product, its thermal stability will be significantly reduced.

In the production of high alumina refractory balls used in the high temperature area of the bed section, its refractoriness and load softening temperature can meet the requirements, but the thermal stability and slag resistance appear to be insufficient. Therefore, surface cracks and slagging bonding often occur, resulting in poor bed permeability and shortened ball cleaning cycle.

2、Silica refractory ball

Silica refractory ball is an acidic refractory material, the mass fraction of SiO2 is more than 93%, other components are mainly Al2O3, Fe2O3, CaO, MgO and some alkali metal oxides. The refractoriness of silica refractory balls is generally 1710-1750℃, and the load softening temperature is higher, up to 1640-1650℃.

Production of silica refractory balls used in the sphere bed section of the high temperature zone, at high temperatures and large gradient temperature change conditions, the ball surface cracking serious, poor resistance to alkaline gas dust erosion ability, slagging bonding phenomenon is serious, clearing the ball is more difficult.

3, Magnesium aluminum refractory ball

Magnesium aluminum refractory ball refractoriness is generally more than 2000 ℃, load softening temperature is generally not higher than 1550 ℃, strong resistance to alkaline slag erosion ability.

Magnesia aluminous refractory ball production process than ordinary magnesium brick fine and strict, its use of performance is also better than ordinary magnesium refractory products; thermal stability is good, 850 ℃ water heat exchange times up to 20 times more; resistance to slag is better, especially the ability to resist Fe2O3 erosion is particularly high. Magnesia alumina refractory balls are suitable for high working temperature and frequent fluctuations in the bed section of the ball.