| 摘要 |
<p>The air cooled walls and base of a glass tank furnace are formed of metal such as carbon steel, or alloy steel such as nickel-chrome alloy, and have a protective coating of refractory enamel comprising SiO2, 50-70%; Al2O3, 3-20%; BaO, 2-20%; Cr2O3, 0-30%; Na2O, 2-10%; and CaO, 2-8%. The melt may form a protective layer on the cooled furnace wall, and this protective layer may be formed by blowing air into the first melt, or by introducing components evolving gas into the charge or by first heating cullet to obtain a frit covering the walls.</p> |
