Category: Refractory Technology

A. Porosity
B. Specific gravity
C. Thermal conductivity
D. Strength

A. Silicon carbide
B. Magnesite
C. Chromite
D. Graphite

A. High thermal conductivity
B. Low porosity
C. Non-wetting characteristics
D. High density

A. Side walls of soaking pits and arc furnaces
B. Copper melting furnaces & converters
C. Burner block of glass tanks
D. All A., B. and C.

A. Obtaining monolithic working faces
B. Repairing construction of various furnace parts
C. Both A. & B.
D. Neither A. nor B.

A. Crushing strength
B. Resistance to slag attack
C. Both A. and B.
D. Neither A. nor B.

A. Electrical conductivity of refractory is not important, when these are to be used in electrical
furnaces
B. Graphite and metals are the good electrical conductor among the refractories and others are all
electrical insulators
C. Refractories used for lining electrical furnaces should ordinarily have very low electrical
conductivity
D. Electrical conductivity of porous refractory material is low

A. CaO
B. MgO
C. Al2O3
D. SiO2

A. Tar dolomite
B. Carbon
C. Silica
D. Fireclay

A. Stable form of silica upto 870°C
B. Converted to Tridymite on firing between 870 to 1470°C
C. Transformed to Cristobalite on heating above 1470°C
D. All A., B. and C.