WorksheetsManufacturing Science and Technology
Total questions: 30
Worksheet time: 36mins
The distortion in casting cannot be prevented by
modification of casting design
modification of casting design
providing sufficient machining allowance to cover the distortion effect
providing proper shrinkage allowance
Which of the following is true in case of directional solidification?
all parts of a casting do not cool at the same time due to varying cross sections
The rate of heat loss varies to adjoining mould walls
The thinnest section solidify first and the riser solidify last
Which of the following is not a casting defect?
Swell
Hot Tears
Shrinkage
Hot Cracks
Which of the following is true for sand castings?
They cannot be used for pressure tight vessels
They are stronger than wrought products
They have lower density and poor strength
They have poor ductility
The function of cores in casting is to
form extended parts
form internal cavities
used for directional solidification
none of the above
According to their use, which of the following is not a type of moulding sand?
Green Sand
Dry Sand
Loam Sand
Wet Sand
In permanent mould casting, the molten metal is poured
under external pressure
under gravity
partially under gravity and partially under external
pressure
none of the above
Which of the following is not true for permanent mould casting?
They are superior in hardness
can be used for pressure tight vessel (upto 15 Kgf/cm2)
can be used for large size castings
not suitable for alloys of high temperature
In semi permanent mould casting
metallic core is used
sand core is used
wooden core is used
no core is used
In hot chamber die casting machine
melting unit is an integral part of machine
It is used for high melting (above 500°C) alloys
No pressure is used for forcing the metal inside the
die
None of the above
In cold chamber die casting machine
melting unit is an integral part of machine
melting chamber is an external part of machine
melting chamber can be placed anywhere
low pressure is required to force the molten metal into
the die casting
Which of the following is true for die used in die casting machine?
One part of die is stationery and other is moveable
Both part of die are stationery
Both part of die are moveable
None of the above
Petrol engine cylinder are made by
Shell moulding
Plaster mould casting
Investment casting
Centrifugal casting
Use of runner, risers and cores are eliminated in
Centrifuged casting
Die casting
Permanent mould casting
Semi permanent mould casting
The metal forming processes is divided in:
hot, cold and warm processes
forging, rolling and extrusion
hot, cold and forging
In the hot working process:
the temperature is BELOW the metal's melting point
the temperature is ABOVE the metal's melting point (higher than the 60% of it)
It's performed at room temperature
How many types of forging processes do we have?
Just one type
We have two types: open die forging and close die forging
We have three types:open die forging, close die forging and hand forging
Which of these is not a stage of powder metallurgy?
Powder manufacture
Compaction
Sintering (heat)
Watering
Which of these is an advantage of powder metallurgy?
High strength
High precision
Low set up cost
Can make any size or shape of object.
Powder metallurgy requires ______ initial investment
High
Low
Which scale of production best suits powder metallurgy?
Mass
One off
Small batch
Which sector is most likely to use powder metallurgy manufactured products?
Communications
Biomedical
Automotive
Electronic
Powder metallurgy process consist of the following operations, in sequence:
powder production, blending, compaction, sintering
powder production, compaction, blending, sintering
sintering, powder production, compaction, blending
Sintering is done to _____________
make the appearance prettier
increase final strength
melt the metal
tidy up the metal
In atomization
joining two or more material either permenantly or temporary
molten plactic polymer is injected into the mould
molten metal is forced through a small orifice and broken up by a stream of compressed air
coating the outer layer of metal to make it more dense
The parts produced by Powder metallurgy_________
are of higher dimensional accuracy
cheaper than others
likely to produced defect items
The operation of cutting sheet metal with help of punch & die on a power press is called...
Cutting
Drawing
Shearing
Squeezing
Which of the following is not involved in sheet metal work?
Bending
Welding
Joining
Cutting
Punching and blanking are essentially the same activity. One leaves you with the positive the other with the negative.
True
False
The useful part in a blanking operation is called...
Blank
Hem
Notch
Stake
