The hot working of metals is carried out
At the recrystallisation temperature
Below the recrystallisation temperature
Above the recrystallisation temperature
At any temperature
Correct Answer :
C. Above the recrystallisation temperature
Related Questions
The electrodes used in spot welding have a tip of
Stainless steel
Aluminium
Copper
Brass
The material which can be best cut with oxygen cutting process is
Mild steel
Brass
Copper
Aluminium
The operation of cutting a cylindrical hole in a sheet of metal by the punch and die is called
Shearing
Piercing
Punching
Blanking
The dowels are
Wooden nails
Box nails
Wire nails
None of these
The mode of deformation of the metal during spinning is
Bending
Stretching
Rolling and stretching
Bending and stretching
The instrument used to measure external and internal diameter of shafts, thickness of parts and depth of holes, is
Outside micrometer
Inside micrometer
Depth gauge micrometer
Vernier caliper
For welding plates of thickness more than 12.5 mm, its edges
Do not require bevelling
Should be bevelled to a single-V or U-groove
Should have a double-V or U-groove on one side
Should have a double-V or U-groove on both sides
The type of file used for a wood work is
Single cut file
Double cut file
Rasp cut file
Any one of these
Blanking and piercing operations can be performed simultaneously in a
Simple die
Progressive die
Compound die
Combination die
The process of decreasing the cross-section of a bar and increasing its length, is called
Drawing down
Upsetting
Spinning
Peening
The welding process used in joining mild steel shanks to high speed drills, is
Spot welding
Seam welding
Flash butt welding
Upset butt welding
The adhesiveness is the property of sand due to which
It evolves a great amount of steam and other gases
The sand grains stick together
It clings to the sides of a moulding box
None of these
The welding set up is said to have straight polarity, when
Work is connected to the positive terminal and the electrode holder to the negative terminal
Work is connected to the negative terminal and the electrode holder to the positive terminal
Work is connected to the positive terminal and the electrode holder is earthed
Work is connected to the negative terminal and the electrode holder is earthed
Which of the following statement is wrong?
The hot chamber die casting machine is used for casting zinc, tin, lead and other low melting alloys.
The cold chamber die casting machine is used for casting aluminium, magnesium, copper base alloys and other high melting alloys.
The castings produced by centrifugal casting method have open and coarse grained structure.
All of the above
The property of sand due to which it evolves a great amount of steam and other gases is called
Collapsibility
Permeability
Cohesiveness
Adhesiveness
The metal patterns as compared to wooden patterns require less
Shrinkage allowance
Machining allowance
Draft allowance
Distortion allowance
The recrystallisation temperature of steel is
400°C
600°C
800°C
None of these
The directional solidification in casting can be improved by using
Chills and chaplets
Chills and padding
Chaplets and padding
Chills, chaplets and padding
In arc welding, the temperature of heat produced by the electric arc is of the order of
3000°C to 4000°C
4000°C to 5000°C
5000°C to 6000°C
6000°C to 7000°C
The width of slot cut by a hacksaw blade is _______ the width of the blade.
Equal to
Less than
Greater than
None of these
The cold chisels are made from
Cast iron
Mild steel
High speed steel
Cast tool steel
The tolerance produced by shell moulding process of casting is
+0.05 mm
±0.2 mm
+0.5 mm
±1 mm
The cold chisels are made by
Drawing
Rolling
Piercing
Forging
A casting defect which occurs due to improper venting of sand is known as
Cold shuts
Blow holes
Shift
Swell
In forehand welding, the angle between the welding torch and the work is ________ as compared to backhand welding.
Same
Less
More
None of these
The cross-section of a chisel is usually
Rectangular
Square
Hexagonal
Octagonal
A file removes the metal during
Forward stroke
Return stroke
Both forward and return strokes
None of these
Which of the following material can be used for making patterns?
Aluminium
Wax
Lead
All of these
Projection welding is a
Continuous spot welding process
Multi-spot welding process
Arc welding process
Process used for joining round bars
In forehand welding, the weld is made
From left to right
From right to left
First from left to right and then from right to left
Either from left to right or from right to left