1Application Of Fused Cast Alumina Block For The Crown Of Glass FurnacesNews

The crowns of glass furnaces are typically made of silica bricks. Recently fused cast alumina block is also used in the crown of glass furnaces, especially oxy-fuel glass furnaces and exhibits advantages over silica bricks.

The crown of the melting and cooling zones of glass furnace is always operated at 1600℃. It is exposed to the conditions of high temperature, erosion of high temperature alkali vapor and batch dusts, and load. Thus the refractory used in the crown is required to have high refractoriness under load, good high temperature creep resistance and good thermal strength. To decrease the heat loss, the refractory should have low thermal conductivity. The most important is that it should not pollute the glass liquid.

Both alpha-beta and beta fused cast alumina blocks have been used for crown in glass furnaces for years. They exhibit excellent corrosion resistance against molten glass and alkali vapor. Fused cast alumina block can generate a dry (alpha alumina) surface in the presence of vapor phases. When in contact with molten glass, they barely produce any blistering or stones, so they cause almost no pollution to the glass liquid.

As alkaline vapors (mainly Na2O from the glass melt) diffuse to the interior of the refractory and react with silica, silica bricks are severely corroded by alkali vapor which results in substantial volume loss. Fused cast alumina blocks exhibit good corrosion resistance to alkali vapor. They can withstand high temperatures than silica brick. The alpha-beta alumina blocks have been exposed to a much wider range of temperature, stress(span), atmospheric chemistry, and length of campaign than beta alumina blocks.

Furthermore, fused cast alumina block can be heated up at a uniform rate, owing to the absence of phase transformation. The crown of fused cast alumina block can be used for multiple campaigns, while the silica brick crown can be used for only a single campaign.

However, the cost of fused cast alumina block is high. Fused cast alumina blocks are more expensive. Besides, due to their high thermal conductivity, heat flow through a furnace crown composed of fused cast alumina is higher than through traditional silica crowns, affecting back-up insulation designs and cooling methods employed on the exterior of the furnace.

Sunrise Refractory offers different type of fused cast Alumina blocks which are made with high purity raw materials and advanced technology. Fused cast alumina block has been used for oxy-fuel furnaces crowns in specialty, float and container glass furnaces.

Fused Cast AZS Block

AZS Casting Type

AZS Ramming Materials

Fused Cast AZS TY-AZS41

Fused Cast AZS TY-AZS36

Fused Cast AZS TY-AZS33

Fused Cast Alumina Block

Fused cast Alumina Block TY-H

Fused cast Alumina Block TY-A

Fused cast Alumina Block TY-M

Fused Cast High Zirconia Block

Fused Cast Skid Rail Block

Silica brick

Magnesia Series Brick

Bonded Refractory Block

High alumina And Fire clay bricks

Insulation Series Brick

Ceramic Fiber Products

Application Of Fused Cast Alumina Block For The Crown Of Glass Furnaces

Need more information? Drop us a line