209 + Mcqs in Refractory Technology Page 1 McqOptions

1.	With increase in the density of silica refractories, its%!
A.	Resistance to slag attack increases
B.	Spalling resistance reduces
C.	Both A & B
D.	Neither A nor B
Answer» D. Neither A nor B

Discussion

2.	Which of the following impurities reduces the refractoriness of magnesite bricks?%!
A.	Al2O‚Äö√á√â
B.	CaO
C.	SiO‚Äö√á√á
D.	All of the above
Answer» E.

Discussion

3.	Resistance to slag attack of a refractory%!
A.	Depends on the nature of slag & refractory
B.	Decreases at higher temperature
C.	Decreases, if defective joints & cracks exist in the refractory
D.	All of the above
Answer» E.

Discussion

4.	Which form of silica has the highest specific gravity?%!
A.	Quartz
B.	Cristobalite
C.	Tridymite
D.	All of the above
Answer» B. Cristobalite

Discussion

5.	Graphite or carbon refractories%!
A.	Exihibit wetting characteristics
B.	Should be used in neutral or reducing atmosphere
C.	Exhibit high shrinkage on thermal treatment
D.	Are not resistant to corrosion by slag
Answer» C. Exhibit high shrinkage on thermal treatment

Discussion

6.	Dilatometer is used for the determination of __________ of refractories.%!
A.	Modulus of rupture
B.	Permanent linear change
C.	Resistance to CO attack
D.	RUL
Answer» C. Resistance to CO attack

Discussion

7.	With decrease in porosity, the __________ of the refractories decreases.%!
A.	Strength
B.	Thermal conductivity
C.	Spalling resistance
D.	None of these
Answer» D. None of these

Discussion

8.	Refractory bricks with lower permeability is produced by using%!
A.	Higher firing temperature
B.	Higher moulding pressure
C.	Finer grog size
D.	All of the above
Answer» E.

Discussion

9.	__________ nozzles are used in continuous casting of steel,%!
A.	Zircon
B.	Thoria
C.	Carborundum
D.	Beryllia
Answer» B. Thoria

Discussion

10.	Bottom of basic open hearth furnace are constructed of%!
A.	Dead burnt magnesite ramming mass
B.	Porous fireclay bricks
C.	Semi-silica bricks
D.	Silicon carbide bricks
Answer» B. Porous fireclay bricks

Discussion

11.	Sillimanite is a __________ refractory.%!
A.	Basic
B.	Neutral
C.	High alumina
D.	Insulating
Answer» D. Insulating

Discussion

12.	Silica refractories%!
A.	Crack when subjected to sudden change of temperature
B.	Can not be used in the dome of hot blast stoves
C.	Have lower thermal conductivity than fireclay bricks
D.	All of the above
Answer» B. Can not be used in the dome of hot blast stoves

Discussion

13.	Silica bricks are never used for lining the%!
A.	Beehive coke ovens
B.	By-product coke ovens
C.	Dome of blast furnace stoves
D.	Roof of open hearth furnace
Answer» B. By-product coke ovens

Discussion

14.	Alumina-graphite bricks are used for lining the%!
A.	Slide gate in teeming laddies
B.	Continuous casting systems
C.	Both A & B
D.	Neither A nor B
Answer» D. Neither A nor B

Discussion

15.	'Spinel', a refractory mineral is chemically represented as%!
A.	MgAl2O‚Äö√á√ë
B.	MgAl2O‚Äö√á√â
C.	MgSO‚Äö√á√ë
D.	MgAl2O‚Äö√á√â.2H‚Äö√á√áO
Answer» B. MgAl2O‚Äö√á√â

Discussion

16.	Which is a basic refractory?%!
A.	Fireclay
B.	Silica
C.	Chrome magnesite
D.	None of these
Answer» D. None of these

Discussion

17.	*$_Silica refractories?
A.	Crack when subjected to sudden change of temperature
B.	Can not be used in the dome of hot blast stoves
C.	Have lower thermal conductivity than fireclay bricks
D.	All of the above
Answer» B. Can not be used in the dome of hot blast stoves

Discussion

18.	*$_Sillimanite is a __________ refractory.?
A.	Basic
B.	Neutral
C.	High alumina
D.	Insulating
Answer» D. Insulating

Discussion

19.	*$_Bottom of basic open hearth furnace are constructed of?
A.	Dead burnt magnesite ramming mass
B.	Porous fireclay bricks
C.	Semi-silica bricks
D.	Silicon carbide bricks
Answer» B. Porous fireclay bricks

Discussion

20.	*$_Graphite or carbon refractories?
A.	Exihibit wetting characteristics
B.	Should be used in neutral or reducing atmosphere
C.	Exhibit high shrinkage on thermal treatment
D.	Are not resistant to corrosion by slag
Answer» C. Exhibit high shrinkage on thermal treatment

Discussion

21.	*$_Refractory bricks with lower permeability is produced by using?
A.	Higher firing temperature
B.	Higher moulding pressure
C.	Finer grog size
D.	All of the above
Answer» E.

Discussion

22.	*$___________ nozzles are used in continuous casting of steel,?
A.	Zircon
B.	Thoria
C.	Carborundum
D.	Beryllia
Answer» B. Thoria

Discussion

23.	*$_Dilatometer is used for the determination of __________ of refractories.?
A.	Modulus of rupture
B.	Permanent linear change
C.	Resistance to CO attack
D.	RUL
Answer» C. Resistance to CO attack

Discussion

24.	*$_With decrease in porosity, the __________ of the refractories decreases.?
A.	Strength
B.	Thermal conductivity
C.	Spalling resistance
D.	None of these
Answer» D. None of these

Discussion

25.	*$_Which is a basic refractory??
A.	Fireclay
B.	Silica
C.	Chrome magnesite
D.	None of these
Answer» D. None of these

Discussion

26.	*$_'Spinel', a refractory mineral is chemically represented as?
A.	MgAl2O‚Äö√á√ë
B.	MgAl2O‚Äö√á√â
C.	MgSO‚Äö√á√ë
D.	MgAl2O‚Äö√á√â.2H‚Äö√á√áO
Answer» B. MgAl2O‚Äö√á√â

Discussion

27.	*$_Alumina-graphite bricks are used for lining the?
A.	Slide gate in teeming laddies
B.	Continuous casting systems
C.	Both A & B
D.	Neither A nor B
Answer» D. Neither A nor B

Discussion

28.	*$_Silica bricks are never used for lining the?
A.	Beehive coke ovens
B.	By-product coke ovens
C.	Dome of blast furnace stoves
D.	Roof of open hearth furnace
Answer» B. By-product coke ovens

Discussion

29.	*$_Zirconia refractory?
A.	Does not react with basic slags
B.	Is produced from baddeleyite
C.	Can not be used as an insulator
D.	Has poor electrical conductivity at high temperature
Answer» C. Can not be used as an insulator

Discussion

30.	*$_Carbon refractories are exclusively used in the?
A.	Hearth of blast furnace
B.	Walls of coke oven
C.	Regenerators of coke oven
D.	Side wall of soaking pits
Answer» B. Walls of coke oven

Discussion

31.	*$_Fireclay refractories have?
A.	Low co-efficient of thermal expansion
B.	Poor thermal spalling resistance
C.	Tendency to expand unduly high during firing
D.	Very high cost
Answer» B. Poor thermal spalling resistance

Discussion

32.	*$_Which is the stable form of silica upto 1470¬¨‚àûC ??
A.	Quartz
B.	Cristobalite
C.	Tridymite
D.	None of these
Answer» D. None of these

Discussion

33.	*$_Silicon carbide refractories are used in the?
A.	Muffle furnace
B.	Zinc smelting furnace
C.	Ceramic recuperators
D.	All of the above
Answer» E.

Discussion

34.	*$_Magnesite refractories have low resistance to?
A.	Attack by basic slag
B.	Abrasion
C.	Disintegration on sudden change of temperature
D.	Both B and C
Answer» E.

Discussion

35.	*$_Which property is important for bricks used in the combustion chamber & dome of blast furnace stoves??
A.	High refractoriness
B.	High resistance to spalling
C.	High strength and density
D.	All of the above
Answer» B. High resistance to spalling

Discussion

36.	*$_Carbon refractory blocks?
A.	Are wetted by molten iron
B.	Are used in the hearth of blast furnace
C.	Are acidic in nature
D.	All of the above
Answer» C. Are acidic in nature

Discussion

37.	*$_Chromite refractories are?
A.	Acidic refractory
B.	Neutral refractory
C.	Basic refractory
D.	Fired at a temperature of 600¬¨‚àûC only
Answer» C. Basic refractory

Discussion

38.	/_The highest melting pure oxide (m.p. > 3000¬¨‚àûC) is?
A.	Thoria
B.	Alumina
C.	Beryllia
D.	Zirconia
Answer» B. Alumina

Discussion

39.	/_Which of the following consumes the maximum tonnage of refractories annually in an integrated steel plant??
A.	Soaking pits
B.	Ceheating furnace
C.	L.D. converter
D.	Rotary lime kiln
Answer» D. Rotary lime kiln

Discussion

40.	/_Chrome magnesite brick is not used for lining the?
A.	Hearth of soaking pits
B.	Bottom hearth of reheating furnace
C.	Coke oven regenerator
D.	Burning zone of limestone rotary kilns
Answer» D. Burning zone of limestone rotary kilns

Discussion

41.	/_Si percentage in silica refractories used in the walls of coke oven is about?
A.	45
B.	60
C.	80
D.	95
Answer» E.

Discussion

42.	/_Chrome magnesite bricks are used in the?
A.	Side walls of soaking pits and arc furnaces
B.	Copper melting furnaces & converters
C.	Burner block of glass tanks
D.	All of the above
Answer» E.

Discussion

43.	/_Refractoriness of a typical silica brick corresponds to Segar cone number, '32', which is equivalent to a temperature of __________ ¬¨‚àûC.?
A.	1380
B.	1520
C.	1710
D.	1915
Answer» D. 1915

Discussion

44.	/_Addition of zircon to silica refractory brick improves its?
A.	Crushing strength
B.	Resistance to slag attack
C.	Neither A nor B
D.	Neither A nor B
Answer» C. Neither A nor B

Discussion

45.	/_Magnesite bricks have poor resistance to attack by __________ slag.?
A.	Lime
B.	Basic
C.	Acid
D.	None of these
Answer» D. None of these

Discussion

46.	/_Hot metal runner in blast furnace are lined with __________ bricks.?
A.	Silica
B.	Carborundum
C.	Fireclay
D.	Magnesite
Answer» D. Magnesite

Discussion

47.	/_Roof of a basic electric furnace is made of __________ bricks.?
A.	Superduty fireclay
B.	Silica
C.	Chromite
D.	None of these
Answer» C. Chromite

Discussion

48.	/___________ is not a single oxiderefractory.?
A.	Zirconia
B.	Silicon carbide
C.	Magnesia
D.	None of these
Answer» C. Magnesia

Discussion

49.	/_Lower part of hot metal mixer are lined with __________ bricks.?
A.	Superduty fireclay
B.	High alumina
C.	Silica
D.	Carborundum
Answer» E.

Discussion

50.	/_An indication of degree of firing in silica brick is its?
A.	Specific gravity
B.	Fusion point
C.	RUL
D.	None of these
Answer» B. Fusion point

Discussion

Explore topic-wise MCQs in Chemical Engineering.

With increase in the density of silica refractories, its%!

Which of the following impurities reduces the refractoriness of magnesite bricks?%!

Resistance to slag attack of a refractory%!

Which form of silica has the highest specific gravity?%!

Graphite or carbon refractories%!

Dilatometer is used for the determination of __________ of refractories.%!

With decrease in porosity, the __________ of the refractories decreases.%!

Refractory bricks with lower permeability is produced by using%!

__________ nozzles are used in continuous casting of steel,%!

Bottom of basic open hearth furnace are constructed of%!

Sillimanite is a __________ refractory.%!

Silica refractories%!

Silica bricks are never used for lining the%!

Alumina-graphite bricks are used for lining the%!

'Spinel', a refractory mineral is chemically represented as%!

Which is a basic refractory?%!

*$_Silica refractories?

*$_Sillimanite is a __________ refractory.?

*$_Bottom of basic open hearth furnace are constructed of?

*$_Graphite or carbon refractories?

*$_Refractory bricks with lower permeability is produced by using?

*$___________ nozzles are used in continuous casting of steel,?

*$_Dilatometer is used for the determination of __________ of refractories.?

*$_With decrease in porosity, the __________ of the refractories decreases.?

*$_Which is a basic refractory??

*$_'Spinel', a refractory mineral is chemically represented as?

*$_Alumina-graphite bricks are used for lining the?

*$_Silica bricks are never used for lining the?

*$_Zirconia refractory?

*$_Carbon refractories are exclusively used in the?

*$_Fireclay refractories have?

*$_Which is the stable form of silica upto 1470¬¨‚àûC ??

*$_Silicon carbide refractories are used in the?

*$_Magnesite refractories have low resistance to?

*$_Which property is important for bricks used in the combustion chamber & dome of blast furnace stoves??

*$_Carbon refractory blocks?

*$_Chromite refractories are?

*/*_The highest melting pure oxide (m.p. > 3000¬¨‚àûC) is?

*/*_Which of the following consumes the maximum tonnage of refractories annually in an integrated steel plant??

*/*_Chrome magnesite brick is not used for lining the?

*/*_Si percentage in silica refractories used in the walls of coke oven is about?

*/*_Chrome magnesite bricks are used in the?

*/*_Refractoriness of a typical silica brick corresponds to Segar cone number, '32', which is equivalent to a temperature of __________ ¬¨‚àûC.?

*/*_Addition of zircon to silica refractory brick improves its?

*/*_Magnesite bricks have poor resistance to attack by __________ slag.?

*/*_Hot metal runner in blast furnace are lined with __________ bricks.?

*/*_Roof of a basic electric furnace is made of __________ bricks.?

*/*___________ is not a single oxiderefractory.?

*/*_Lower part of hot metal mixer are lined with __________ bricks.?

*/*_An indication of degree of firing in silica brick is its?

/_The highest melting pure oxide (m.p. > 3000¬¨‚àûC) is?

/_Which of the following consumes the maximum tonnage of refractories annually in an integrated steel plant??

/_Chrome magnesite brick is not used for lining the?

/_Si percentage in silica refractories used in the walls of coke oven is about?

/_Chrome magnesite bricks are used in the?

/_Refractoriness of a typical silica brick corresponds to Segar cone number, '32', which is equivalent to a temperature of __________ ¬¨‚àûC.?

/_Addition of zircon to silica refractory brick improves its?

/_Magnesite bricks have poor resistance to attack by __________ slag.?

/_Hot metal runner in blast furnace are lined with __________ bricks.?

/_Roof of a basic electric furnace is made of __________ bricks.?

/___________ is not a single oxiderefractory.?

/_Lower part of hot metal mixer are lined with __________ bricks.?

/_An indication of degree of firing in silica brick is its?