Refractory Technology Questions

• Thoria is an expensive refractory material and is radioactive in nature. Thorium oxide is used in the manufacture of
• Refractoriness of a typical silica brick corresponds to Segar cone number, '32', which is equivalent to a temperature of __________ °C.
• Chemically, mullite refractories is
• Which is the stable form of silica below 870°C?
• Firing of refractory brick is done to
• Maximum alumina content in high alumina refractory can be as high as __________ percent.
• Spalling of silica bricks occurs due to abrupt volume changes, when it is cooled below a temperature of __________ °C.
• Firing temperature of magnesite bricks is about __________ °C.
• Fireclay bricks are used in the
• Panel test determines the __________ of refractories.
• Vacuum steel degassing units are lined with
• Fusion point of a basic refractory material is
• Roof of a basic electric furnace is made of __________ bricks.
• An insulating refractory brick should have high porosity and low thermal conductivity. Which of the following is not used for inducing porosity in the insulating refractory bricks during its manufacture?
• Hollow refractory bricks are made by
• Which one expands on heating?
• Outer combustion chamber of blast furnace stove is lined with __________ bricks.
• Refractories are dried in the
• Magnesite refractories are used for the construction of those furnaces, which are
• Cermets are combination of ceramic and metallic materials due to which they have high strength & resistance to high temperature. Cermets are used in the