The process of decarbonising the pig iron completely and then adding proper percentage of carbon for manufacturing steel, is called
Cementation process
Crucible process
Bessemer process
Open hearth process
Correct Answer :
A. Cementation process
Related Questions
The portion of a brick cut to form angles other than right angles in plan, is known as
Queen closer
King closer
Closer
Squint brick
Pick up the correct statement from the following:
The low voltage porcelain is prepared by wet process
The high voltage porcelain is prepared by dry process
The low voltage porcelain is prepared by dry process
None of the above
Pick up the correct statement from the following:
The free quartz suddenly expands at a temperature lower than 600°C
The lime stone resists fire upto about 800°C and at higher temperature it splits into CaO and CO2
The sand stone with silicates resist a fire in a better way
All the above
If the iron ore contains clay as an impurity, the flux added during calcination, is
Clay
Lime stone
Argillaceous iron ore
All the above
The proportions of lime and sand in the mortar normally used in brick construction are
1 : 2
1 : 4
1 : 6
1 : 8
The cracks caused by shrinkage of the exterior surface of the wood exposed to atmosphere, are called:
Radial shakes
Heart shakes
Wind cracks
Twisted fibres
Based on flow quality, the sequence of pipes is
A.C. pipes, G.I. pipes, C.I. pipes, PVC pipes
C.I. pipes, G.I. pipes, A.C. pipes, PVC pipes
C.I. pipes, G.I. pipes, PVC pipes, A.C. pipes
None of these
The thermosetting plastic
Becomes rigid when moulded at suitable pressure and temperature
At 127°C to 177°C permanently set and further application of heat does not soften it
Chars at 343°C
All the above
Pick up the correct statement from the following:
The phenol is carbolic acid
The phenol is either extracted from coal-tar or prepared from benzene
Phenol reacts with formaldehyde, to form phenol formaldehyde resin
All the above
For filling cracks in masonry structures, the type of bitumen used, is
Cut-back bitumen
Bitumen-emulsion
Blown bitumen
Plastic bitumen
The yield strength and tensile strength of low carbon steel may be improved by the addition of
Manganese
Chromium
Nickel
Vanadium
The percentage of alumina and silica in good fire clay vary respectively is
25, 75
30, 70
35, 65
All of these
Cement paints usually
Contain hydrated lime
Contain 5% to 10% colour pigments
Contain 5% sodium chloride
All the above
The plastics prepared from Vinyl resin are
Odourless
Non-toxic
Transparent
All of these
Gneiss is obtained from
Igneous rocks
Metamorphic rocks
Sedimentary rocks
Sedimentary metamorphic rocks
For a good building stone, its specific gravity should the greater than
1.5
1.7
2.2
2.7
Which of the following cements is suitable for use in massive concrete structures such as large dams?
Ordinary Portland cement
Low heat cement
Rapid hardening cement
Sulphate resisting cement
Upto a maximum of 72% of iron, is available in
Magnetite
Limonite
Siderite
Iron pyrites
Granite mainly composed of quartz and feldspar particles, is obtained from
Sedimentary rocks
Metamorphic rocks
Igneous rocks
All the above
Pick up the correct statement from the following:
Adding 5% to 6% of moisture content by weight, increases the volume of dry sand from 18% to 38%
The bulking of fine sand is more than that of coarse sand
If the percentage content of moisture exceeds 10%, increase in bulk of sand starts increasing
All the above
Which one of the following is an air binding material?
Gypsum
Acid-resistant cement
Quick lime
All of these
Teak wood is suitable for
Sports articles
Furnitures
Railway sleepers
All the above
The age of a tree can be known by examining
Cambium layer
Annular rings
Medullary rays
Heart wood
The frog of the brick in a brick masonry is generally kept on
Bottom face
Top face
Shorter side
Longer side
The main constituent which imparts hydraulicity to hydraulic lime is
Calcium oxide
Silica
Clay
Water
Depending on the chemical composition and mechanical properties, iron may be classified as
Cast iron
Wrought iron
Steel
All the above
Gypsum consists of
H₂S and CO₂
CaSO4 and H₂O
Lime and H₂O
CO₂ and calcium
Which one of the following polymers is obtained from condensation polymerization?
Phenol formaldehyde
Carbamide
Melamine-formaldehyde
All of these
Pick up the incorrect statement from the following:
Hydraulic lime is generally obtained by burning kankar
Hydraulic lime sets slowly as compared to fat lime
Hydraulic lime is generally used in lime mortar
None of these
In arches, stratified stones are placed so that their planes are
Parallel
Perpendicular
Radial
None of these