Refractoriness/fusion points of 'superduty' refractories is __________ °C.

Vacuum steel degassing units are lined with

Fireclay bricks are used in the

Beryllia (which is used in making crucibles for melting uranium & thorium) is superior to alumina in all respects for high temperature (> 1900°C ) use, except

Fireclay bricks are not used in the

Outer combustion chamber of blast furnace stove is lined with __________ bricks.

Pyrometric cone equivalent (PCE) value (Segar cone) of 'superduty refractories' is more thanwhich corresponds to a temperature of __________ °C.

Which is the stable form of silica below 870°C ?

Water content in ground refractory material to be shaped into bricks by hand moulding is about __________ percent.

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 ?

Fusion point of a basic refractory material is

RUL of refractories depends on the

With increase in the alumina content, the refractoriness of high alumina refractories

Resistance to slag attack of a refractory

Presence of MgO in alumino-silicate refractories __________ its refractoriness.

Chromite refractories

Firing of refractory brick is done to

Which is the stable form of silica between 1470°C and the melting point 1713°C ?

A steel member used in the furnace construction to take the thrust of the brickwork is called

Grog

Capacity of a refractory brick to withstand-sudden changes in temperature is denoted by the property called

Spalling of silica bricks occurs due to abrupt volume changes, when it is cooled below a temperature of __________ °C.

Firing temperature is minimum (1250-°C) for __________ bricks.

Chemically, mullite refractories is

Refractories are dried in the

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

With increase in the porosity, thermal spalling resistance of fireclay brick

Thoria is an expensive refractory material and is radioactive in nature. Thorium oxide is used in the manufacture of

Test piece for determination of RUL of a refractory is heated in a/an

Magnesite bricks are used in those parts of furnaces, which are