Applications Of Refractory Material In Float Glass Furnaces

Float glass furnaces are used to make flat toughened glass which is widely used in the fields of architecture, decoration, furniture, electronic apparatus, vehicles, ships, aviation, and more. Float glass furnaces consist of three main parts, the melter, refiner and regenerators or checkers.

The Melter is a rectangular basin in which the actual melting and fining (seed removal) takes place. In a side-fired furnace, the batch is charged into the furnace through the doghouse, which is an extension of the melter, protruding from the back wall. Along each side of the melter, above glass level, are three to seven ports, which contain the natural gas burners and direct the combustion air and exhaust gases.

In the melter zone, due to its high temperature and severe corrosion, fused cast AZS block 41# and 36# are used in the sidewall, electrode block, bubbling block and other glass contact areas. Fused cast alumina block and fused cast high zirconia block are also use in the glass contact areas for special glass furnaces.

The melter basin is separated from the refiner by the bridge wall (throat end wall). Glass passes from the melter to the refiner through the throat, which is a water-cooled tunnel that extends through the bridge wall. The throat is always subjected to strong attack and severe corrosion, so fused cast AZS block 41# and 36# are used here.

The Refiner acts as a holding basin where the glass is allowed to cool to a uniform temperature before entering the forehearths. The melter and refiner are covered by crowns to contain the heat. In the refiner zone, the temperature is lower and the wear and corrosion is not so severe, so fused cast AZS block 33# is used here.

The regenerators consist of two chambers, each of which is filled with a network of refractories, referred to as the packing. Regenerator chambers are normally vertical constructions in which the waste gases pass downwards, whilst the combustion air travels upwards. There are various forms of regenerator packing, but only two are now widely used. Both designs utilise specially shaped blocks, cross-shapes for the cruciform system, and square section tube shapes for the chimney block system.

The top courses of regenerator checkerwork are subjected to high temperature and severe attack and magnesia block is employed here. In the middle courses, as the temperature is lower, magnesia block with lower content of MgO is used here. In the lower courses, as the atmosphere is not quite severe, fireclay brick is always used here as an economic choice.

Sunrise Refractory is a refractory supplier from China, specializing in all types of refractory materials used in glass making. The main products are as follows: fused cast AZS, mullite brick, zircon brick, alumina bubble brick, sillimanite brick, corundum brick, fireclay brick, high alumina brick, ramming masses, insulating materials, etc.