Cold crushing strength of ordinary fireclay brick is about 950 kg/cm2. On exposure to a temperature of about 1500°C, its crushing strength may come down to as low as __________ kg/cm2.
A. 450
B. 250
C. 150
D. 65
Answer: Option D
A. 450
B. 250
C. 150
D. 65
Answer: Option D
Fusion point of an acidic refractory material is
A. Increased by the addition of basic oxides
B. Reduced by the addition of basic oxides
C. Not affected by the addition of basic oxides
D. None of the above
Which of the following is not a high alumina refractory material?
A. Kyanite
B. Sillimanite
C. Diaspore
D. Periclase
Magnesite refractories are generally not used in the
A. Electric furnace walls
B. Steel melting furnace
C. Open hearth furnace
D. Burning zone of cement kilns
How is this happed