Fused Cast AZS Block 33# For Glass Furnaces

The mostly applied type of refractory in the glass industry, in direct contact with the glass melt, is fused cast AZS block. It is available in a number of grades, principally distinguished by zircon content: 33#, 36# and 41#. The AZS 33# block is the most common product used for less severe glass contact areas in the glass furnace.

AZS 33# block contains 33% ZrO2. Its producting process includes molds, melting, casting and annealing. First the raw materials are melted in an electric arc furnace at about 2200-2400 ℃. The melt is treated with oxygen to oxidize zirconium oxy-carbo-nitride or other reduced constituents, produced by the reaction with the graphite electrodes during melting. The molten material is then cast into molds to, or very near to, the final shape of the block desired. The mold with the fused cast ceramic is cooled down very slowly in order to anneal (free of thermal stresses) the fused cast product. 

 

AZS 33# has dense micro structure which ensures its great erosion resistibility to molten glass. It is unlikely to cause defections of stones, blisters and cords. It also has good thermal shock resistibility and high compression resistance. It is available in a variety of formats and shapes for different working areas of glass furnaces.

 

AZS 33# block is most suitable for superstructures of melters, side walls of refiners, paving blocks, port Area, port Lining and forehearth channel blocks. They are particularly useful in electric furnace (cold crown type melters), sidewalls and orifice assembly protection blocks where exceptional thermal shock characteristics and resistance to high alkali glass is required or in other applications where resistance to hot corrosive slags is needed.

 

According to the casting method, fused cast AZS 33# block can be divided into Normal casting(PT), Tilt casting(QX), Semi-Void-Free casting(ZWS) and Void-free casting(WS). 

 

The unique technology of PT casting changes distribution of shrinkage voids of regular casting bricks, reduces shrinkage voids, and increases the dependability of bricks. It is recommeded for superstructure, working end and feeder channel, etc. Due to the material’s excellent castability, this product can be made into kinds of different shapes and sizes such as Feeder channel block, thermocouple block, tuck stone, crown and burner block.

 

The voids are small and located at bottom of the brick, which should be down when the brick is used. This product is designed for the sidewalls of flame furnaces with embedded melted bottoms, for total, security with average pulls and campaign lengths. This product is only available for straight brick or approximate ones.

 

The 33WS block is cast from exclusive riser, which assures the melted liquid cast into the model almostly. This product is designed for the special places of flame furnace, such as side wall, tank bottom, superstructure, feeder channel, bowl, bleeder, C shaped brick, etc. 

 

The fused cast AZS 33# block from Sunrise Refractory has passed the ISO international certified. High purity raw material, scientific formula, advanced technology and professional guide all contribute to our qualified azs blocks production.