The parts of circular cross-section which are symmetrical about the axis of rotation are made by
Hot forging
Hot spinning
Hot extrusion
Hot drawing
Correct Answer :
B. Hot spinning
Related Questions
The algebraic difference between the maximum limit and the basic size is called
Actual deviation
Upper deviation
Lower deviation
Fundamental deviation
The process of decreasing the cross-section of a bar and increasing its length, is called
Drawing down
Upsetting
Spinning
Peening
V-block is used to
Check the trueness of flat surfaces
Locate centres of round rods
Check the surface roughness
None of these
According to Indian standard specifications, 100 H6/g 5 means that.
Basic size is 100 mm
Actual size is 100 mm
Difference between the actual size and basic size is 100 mm
None of the above
The current in electric resistance welding can be regulated by
Varying the input supply
Changing the primary turns of the transformer
Changing the secondary turns of the transformer
Any one of the above
The purpose of a gate is to
Delivers molten metal into the mould cavity
Act as a reservoir for the molten metal
Feed the molten metal to the casting in order to compensate for the shrinkage
Delivers molten metal from pouring basin to gate
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
In order to cut mild steel, the cutting angle of chisel should be
30°
45°
50°
60°
In a bilateral system of tolerance, the tolerance is allowed on
One side of the actual size
One side of the nominal size
Both sides of the actual size
Both sides of the nominal size
In a gas welding of mild steel using an oxyacetylene flame, the total amount of acetylene consumed is 10 litres. The oxygen consumption from the cylinder is
5 litres
10 litres
15 litres
20 litres
The advantage of Thermit welding is that
All parts of the weld section are molten at the same time
Weld cools almost uniformly
Results in a minimum problem with internal residual stresses
All of the above
In a hot chamber die casting machine
Ferrous alloys with low melting temperature are casted
Ferrous alloys with high melting temperature are casted
Nonferrous alloys with low melting temperature are casted
Nonferrous alloys with high melting temperature are casted
In a four high rolling mill, the diameter of backing up rolls is ________ the diameter of working rolls.
Equal to
Smaller than
Larger than
None of these
During drawing operation, the states of stress in cup would include
Compressive stress in the flange
Tensile stress in the wall
Both (A) and (B)
None of these
The punch and die set up is ________ for punching and piercing operation.
Same
Similar
Different
None of these
The dowels are
Wooden nails
Box nails
Wire nails
None of these
In order to deliver molten metal from pouring basin to gate, a ________ is used.
Riser
Sprue
Core
None of these
When a hole or cavity to be cored is not in line with the parting surface, then a ________ is used.
Horizontal core
Vertical core
Drop core
Balanced core
In ________ welding, the weld may be made either from left to right or from right to left.
Forehand
Backhand
Vertical
None of these
Neutral flame is used to weld
Steel
Cast iron
Copper
All of these
The acetylene cylinder is usually painted with
Black colour
White colour
Maroon colour
Yellow colour
A ring gauge is used to
Check the diameter of shafts or studs
Test the accuracy of holes
Check the clearance between two mating surfaces
All of the above
The oxygen cylinder is usually painted with
Black colour
White colour
Maroon colour
Yellow colour
For arc welding
Alternating current with high frequency is used
Alternating current with low frequency is used
Direct current is used
Any one of these
The surface to be machined is marked on the pattern by
Red colour
Yellow colour
Black colour
Blue colour
Thermit welding is often used in
Replacing broken gear teeth
Repairing broken shears
Joining rails, truck frames and locomotive frames etc.
All of the above
Piercing is an operation of cutting
A cylindrical hole in a sheet of metal by the punch and the die
A hole (other than cylindrical) in a sheet of metal by the punch and the die
A flat sheet to the desired shape
A number of holes evenly spaced in a regular pattern on a sheet of metal
The edge of a steel plate cut by oxygen cutting will get hardened when the carbon content is
Less than 0.1 percent
Less than 0.3 percent
More than 0.3 percent
Anywhere between 0.1 to 1 percent
In sheet metal work, he cutting force on the tool can be reduced by
Grinding the cutting edges sharp
Increasing the hardness of tool
Providing shear on tool
Increasing the hardness of die
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