Glass refractory burned 1860 degree ultra high temperature tunnel kiln with automatic control system. AZS fused cast refractory manufactured from high purity materials by long arc fused cast procedd with a special electric arc furnace. This electric furnace hardly causes any carbon contamination from the electrode. Dese zircon brick adopt 36000Mt isostatic press machine. So they have high alkali corrosion resistance and thermal shock resistance.