Refractory Technology Questions

• An ideal refractory should have high
• Highest melting (m.p = 3070°C) oxide refractory is
• SiO2 percentage in firebrick is about
• Maximum apparent porosity of magnesite bricks is about __________ percent.
• Mullite is chemically represented by
• Graphite or carbon refractories
• Dilatometer is used for the determination of __________ of refractories.
• The maximum linear expansion of silica bricks during firing is about __________ percent.
• Upper portion of hot metal mixer are lined with mullite bricks, which helps in resisting the
• Use of higher percentage of lime for bonding silica bricks, reduces their
• Semi-silica bricks compared to silica bricks have
• Rate of slag attack on refractories increases with rise in temperature due to the
• Chrome magnesite brick is not used for lining the
• To resist spalling tendency, a refractory should have
• Grog addition in fireclay during brick manufacture is done to
• Roof of a basic open hearth furnace is lined with __________ bricks.
• Which property is important for bricks used in the combustion chamber & dome of blast furnace stoves?
• Spalling tendency of refractories is reduced by increasing its
• Colour of fireclay bricks is
• Which is the stable form of silica upto 1470°C?