Category: Refractory Technology

A. Refractoriness
B. Melting point
C. Rate at which a fluid will pass through the pores
D. Expansion during heating

A. Sand & coke is the main raw material for the manufacture of silicon carbide
B. Carbon refractories cannot be used in the furnaces operating under reducing conditions
C. Mullite can be obtained by the heating of alusite, kyanite or sillimanite
D. Silica occurs in nature in all cellular, amorphous or crystalline form

A. Low co-efficient of thermal expansion
B. Poor thermal spalling resistance
C. Tendency to expand unduly high during firing
D. Very high cost

A. Tar bonded dolomite bricks
B. Fireclay bricks
C. Mullite bricks
D. Magnesite bricks

A. Increases with rise in service temperature
B. Decreases with rise in service temperature
C. Is unaffected with change in service temperature
D. Decreases with increase in porosity

A. Buckstay
B. Breast wall
C. Armouring
D. Baffle

A. Increasing its porosity
B. Using a coarser grog during its manufacture
C. Decreasing its thermal co-efficient of expansion
D. Making it denser

A. 0.5
B. 1
C. 2
D. 3.5

A. Aluminium phosphate
B. Water
C. Lime
D. Plaster of Paris

A. Refractories used in muffle furnace should have low thermal conductivity
B. The electrical resistivity of refractories drops rapidly with rise in temperature
C. For reducing spalling tendency, the refractory should be well fired and its porosity should be
more
D. Refractoriness under load (RUL) of a refractory is always less than its refractoriness