Refractory Technology MCQs

Question 1

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?

Accepted Answer

Sand

Answer

Cork

Answer

Saw dust

Answer

Chemically prepared foam

Question 2

Which is a basic refractory?

Accepted Answer

Chrome magnesite

Answer

Fireclay

Answer

Silica

Answer

None of these

Question 3

Refractory bricks with lower permeability is produced by using

Accepted Answer

All of the above

Answer

Higher firing temperature

Answer

Higher moulding pressure

Answer

Finer grog size

Question 4

Porosity is induced in insulating refractories by adding

Accepted Answer

All of the above

Answer

Powdered naphthalene

Answer

Ammonium chloride/sulphate

Answer

Calcium phosphate

Question 5

Ramming masses are used for

Accepted Answer

Both A & B

Answer

Obtaining monolithic working faces

Answer

Repairing construction of various furnace parts

Answer

Neither A nor B

Question 6

Colour of fireclay bricks is

Accepted Answer

Light buff to reddish buff

Answer

Yellow

Answer

Black

Answer

None of these

Question 7

The main raw material for manufacture of silicon carbide refractories is

Accepted Answer

Carborundum

Answer

Corrundum

Answer

Bauxite

Answer

Periclase

Question 8

Chromite refractories are

Accepted Answer

Neutral refractory

Answer

Acidic refractory

Answer

Basic refractory

Answer

Fired at a temperature of 600°C only

Question 9

Which property of refractories is the most important for top section of the blast furnace?

Accepted Answer

Resistance to abrasion

Answer

Resistance to slag peneration

Answer

Stability of volume at high temperature

Answer

Resistance to corrosion by slag