Explore topic-wise MCQs in Engineering.

Hollow refractory bricks are made by

Quartz is

Skull is not formed on the carbon blocks in the hearth of a blast furnace, when it becomes cold, becaus of its

Pyrometric cone equivalent (PCE) of a refractory is the measure of its

Bauxite calcining rotary kilns are lined with __________ bricks.

Silica refractories are not used in

Refractory materials are never used in the construction of

Segar cones are used for the determination of __________ of refractories.

Carbon refractories have very high

Sillimanite is a __________ refractory.

High refractorinness of refractory bricks means, that it has a

Conversion of silica mineral to cristobalite is accompanied by reduction in its

Chrome magnesite is not used in the

Which of the following bricks has the most close values of RUL and PCE ?

Tar dolomite bricks are used in the

Which furnace consumes maximum refractory annually in an integrated steel plant ?

Lower part of hot metal mixer are lined with __________ bricks.

An indication of degree of firing in silica brick is its

Vacuum steel degassing units are lined with

The main raw material for manufacture of silicon carbide refractories is

Chromite refractories are used in

Which of the following has the lowest electrical resistivity ?

Silica bricks have low spalling resistance below 600 C, due to its

Spalling of a refractory means its

Carbon refractories are exclusively used in the

Spalling tendency of refractories is reduced by increasing its

Dry mix hydraulic compositions of refractory aggregates with suitable bonding materials are called refractory

Bottom of basic open hearth furnace are constructed of

Lower wall courses of soaking pits are made of __________ bricks to avoid the action of molten slag & scale.

Addition of grog in fireclay brick during its manufacture is advantageous, because it results in

Slide gates in teeming laddie used for steel pouring in ingot moulds is lined with __________ bricks.

Which form of silica has the highest specific gravity ?

Ceramic recuperators used for waste heat recovery from high temperature flue gas going out of the furnace is made of

__________ is the measure of the strength of refractory under the combined effect of temperature & load.

Crushing strength of a refractory

Fireclay bricks are not used in the

Ramming masses are used for

In panel test for spalling resistance, the average face temperature of panel assembly is maintained at __________ C for 24 hours.

Refractories used in/for __________ should have low thermal conductivity.

10 to 30% magnesite is added to chromite to produce chrome-magnesite refractories. Magnesite addition is mainly done to improve the __________ of chromite.

Which is not a natural insulating material?

Magnesite refractories are generally not used in the

Rotary kilns meant for calcination of limestone are lined with chrome magnesite in __________ zone.

Which is not an acidic refractory ?

Natural silica

Thermal conductivity of refractory bricks

Which of the following bricks should not be used, if the furnace is to be used intermit-tantly ?

Upper portion of hot metal mixer are lined with mullite bricks, which helps in resisting the

Grog addition in fireclay during brick manufacture is done to

Zirconia refractories are not used in