A three high rolling mill consists of three rolls placed one above the other. Which of the following statement is correct?
The upper and middle rolls rotate in the same direction whereas the bottom roll rotates in opposite direction
The upper and bottom rolls rotate in the same direction whereas the middle roll rotates in opposite direction
The bottom and middle roll rotate in the same direction
Any one of the above
Correct Answer :
B. The upper and bottom rolls rotate in the same direction whereas the middle roll rotates in opposite direction
Related Questions
If an aluminium pattern made from a wooden master pattern is to be used for grey iron castings, then the shrinkage allowance allowed on the wooden pattern should be
10 mm/m
16 mm/m
20 mm/m
26 mm/m
A file with 20 teeth in 25 mm is called
Rough file
Bastard file
Second cut file
Smooth file
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
A rip saw
Is a two man saw
Is used for cutting along the grains of wood
Has a narrow blade with two wooden handles
All of the above
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
Which of the following methods can be used for manufacturing 2 metre long seamless metallic tubes?
Drawing
Extrusion
Rolling
Extrusion and rolling
The temperature of the inner luminous cone of neutral flame is about
1000°C
1250°C
2100°C
3200°C
The metal extrusion process is generally used for producing
Uniform solid sections
Uniform hollow sections
Uniform solid and hollow sections
Varying solid and hollow sections
The upsetting is a process of
Increasing the cross-section of a bar
Reducing the cross-section of a bar
Joining the two surfaces of metal under pressure after heating
Bending of a bar
The accuracy of micrometers, calipers, dial indicators can be checked by a
Feeler gauge
Slip gauge
Ring gauge
Plug gauge
Extrusion
Is extensively used for making bolts and nuts
Is used for reducing the diameter of round bars and tubes by rotating dies which open and close rapidly on the work
Is used to improve fatigue resistance of the metal by setting up compressive stresses in its surface
Consists of pressing the metal inside a chamber to force it out by high pressure through an orifice which is shaped to provide the desired form of the finished part
In backhand welding, the angle between the welding torch and the work is kept as
30°-40°
40°-50°
50°-60°
60°-70°
The brass and bronze are welded by _________ flame.
Neutral
Oxidising
Carburising
All of these
The oxygen cylinder is usually painted with
Black colour
White colour
Maroon colour
Yellow colour
The machining allowance provided on patterns depends upon
Type of casting metal
Size and shape of casting
Method of casting used
All of these
Which of the following welding method uses a pool of molten metal?
Carbon arc welding
Submerged arc welding
TIG arc welding
MIG arc 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
A neutral flame is obtained by supplying
Equal volumes of oxygen and acetylene
More volume of oxygen and less volume of acetylene
More volume of acetylene and less volume of oxygen
None of the above
A zinc diffusion process is called
Galvanising
Anodising
Parkerising
Sherardizing
Carburising flame is used to weld
Steel, cast iron, copper, aluminium etc
Brass and bronze
Hard surfacing materials such as stellite
All of these
A mortise gauge is a
Striking tool
Planing tool
Boring tool
Marking tool
Which of the following material can be used for making patterns?
Aluminium
Wax
Lead
All of these
In arc welding, the electric arc is produced between the work and the electrode by
Voltage
Flow of current
Contact resistance
All of these
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 teeth of hacksaw blade are bent
Towards right
Towards left
Alternately towards right and left and every third or fourth left straight
May be bent in any direction
In a four high rolling mill, there are four rolls out of which
One is working roll and three are backing up rolls
Two are working rolls and two are backing up rolls
Three are working rolls and one is backing up roll
All of the four are working rolls
The shrinkage allowance for cast iron pattern is
10 mm/m
16 mm/m
20 mm/m
26 mm/m
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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
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Drawing down
Upsetting
Spinning
Peening
In TIG arc welding, the welding zone is shielded by an atmosphere of
Helium gas
Argon gas
Either (A) or (B)
None of these