Deck 4: Mechanical Engineering: Casting, Machining, and Welding

Question 1

In gas welding the maximum flame temperature occurs at

A)Inside the inner cone
B)The inner cone
C)Next to the inner cone
D)The outer cone
E)The tip of the flame

Answer 1

Next to the inner cone

Question 2

Silicon steel is used for

A)Ball bearings
B)Boiler plates
C)Industrial knives
D)Dies
E)Electrical stampings

Answer 2

Electrical stampings

Question 3

The efficiency of abrasive particles depends up

A)purity
B)uniformity in composition
C)hardness
D)All of the above
E)Parting off

Answer 3

All of the above

Question 4

The hardness of martensite in quenched plain carbon steels reaches almost a saturation value of carbon of about

A)0.20%
B)0.40%
C)0.60%
D)1.40%
E)None of the above

Question 5

In centreless grinding the work piece advances by

A)Force exerted by regulating wheel
B)Remains stationalry
C)Hydraulic force
D)Force exerted by grinding wheel
E)Push given by operator

Question 6

The power consumption in ultrasonic machining in kW/m²/min is of the order of

A)200 kW/m³/min
B)1000 kW/m³/min
C)1 kW/m³/min
D)10 kW/m³/min
E)100 kW/m³/min

Question 7

Shell sands are coated with

A)molasses
B)urea formaldehyde
C)carbon disulphide
D)Parting off
E)silica grains

Question 8

A very soft whisper may have noise level of

A)About 100 db
B)About 140 db
C)About 30 db
D)About 40 db
E)About 10 db

Question 9

The width of slot eut by a hack-saw blade is

A)None of these
B)Less than the width of blade
C)Slightly more than the width of blade
D)Equal to the width of blade
E)1830 rpm

Question 10

Swell is a defect in castings due to

A)Enlargement of the mould cavity by metal pressure causing partial or overall enlargement of the casting
B)Working on cooling
C)Moisture in moulding sand
D)Thin projection of casting due to gap between flasks
E)Mis-mathcing of mould at the parting line

Question 11

In EDM the material of the tool is

A)Carbide
B)Copper
C)Satellite
D)Diamond
E)High speed steel

Question 12

In a centre lathe gear box for changing spindle speeds the provision for speeds is made in

A)Arithmetical progression
B)Geometrical progression
C)Cubical progression
D)Random members
E)Square progression

Question 13

In rubber bond for grinding wheels, sulphur is added to

A)Parting off
B)act as vulcanising agent
C)reduce shocks and vibrations
D)make the bond flexible
E)dissipate heat during grinding operation

Question 14

Profile of a gear tooth is to be checked. Which one of the following device would you choose?

A)Sine bear
B)Optical projector
C)Optical pyrometer
D)Bench micrometer
E)Telescopic gauge

Question 15

A chisel is used for

A)Cutting the wood
B)Planing the wood
C)Making holes in the wood
D)None of the above
E)Parting off

Question 16

Chips with built up edge are produced while machining

A)Non-ferrous materials
B)Cast materials
C)Hard materials
D)Brittle material
E)Ductile material

Question 17

Discontinuous or segmental chips are formed while machining

A)Mild steel
B)Brass
C)Carbon steel
D)Alloy steel
E)Cast iron

Question 18

Which of the following is a single point cutting tool?

A)Milling cutter
B)File
C)Grinding wheel
D)Parting tool
E)Hacksaw blade

Question 19

While using cemented carbide tipped tools on aluminium, the cutting speed could be

A)100 - 300 m/min
B)1000 m/min
C)20 - 50 m/min
D)300 - 900 m/min
E)50 - 100 m/min

Question 20

A silver point is

A)The temperature of equilibrium between solid silver and liquid silver at normal atmospheric pressure
B)The pointed location spot silver plated
C)The temperature of equilibrium between liquid silver and silver vapour at normal atmospheric pressure
D)The point on a instrument dial reading beyond which may be dangerous for the system
E)The temperature at which silver melts

Question 21

In order to avoid unscrewing while on a bicycle the shaft or the right padel is screwed in with

A)Right hand thread
B)Left hand thread
C)Hysteresis

Question 22

The Roman notation DCCCC represents

A)900
B)440
C)340
D)90
E)140

Question 23

During arc welding eyes need to be protected against

A)Microwaves
B)Infrared and ultraviolet rays
C)Intense glare
D)X-rays and gamma rays
E)High frequency waves

Question 24

In EDM the number of discharges perminute may be as high as

A)3000
B)6000
C)6,000,000
D)60,000
E)600,000

Question 25

Undercutting is

A)An operation of cutting deep grooves
B)None of above
C)An operation of cutting a groove next to a shoulder on a piece of work
D)An operation of cutting extra wide threads
E)Cutting from the base of a work piece

Question 26

The minimum section thickness for cast iron castings is

A)10 mm
B)Parting off
C)3 mm
D)1 mm
E)6 mm

Question 27

When large number of components are turned and parted off from a bar, the chuck used is

A)Magnetic chuck
B)Four jaw chuck
C)Collet chuck
D)Face place
E)Three jaw chuck

Question 28

Which of the following plate can be used for milling the sides of a hexagon nut?

A)Parting off
B)3 hole circle plate
C)45 hole circle plate
D)55 hole circle plate
E)24 hole circle plate

Question 29

Stub tooth are cut on gears

A)To improve transmission efficiency
B)To reduce centre distance between shafts
C)None of above
D)To reduce frictional torque
E)Subjected to shock and vibration

Question 30

Porosity of a welded joint may be caused by

A)Poor base metal
B)Low welding current
C)High welding current
D)Wrong size of electrode
E)None of the above

Question 31

Ionised material acts as transfer media in case of

A)Ion beam machining
B)Plasma arc machining
C)Electro discharge machining
D)All of the above
E)None of the above

Question 32

Scale sensitivity is defined as

A)Ratio of a change in scale reading to the corresponding change in pointer deflection
B)Least reading of scale/range of scale
C)Least reading of scale/unit measurable quantity
D)Least count of scale/range of scale
E)None of the above

Question 33

Which one does not fit with the rest in the following

A)Hammer
B)Flatter
C)Hot chiesel
D)Reamer
E)Hot punch

Question 34

Kerosene is used as a cutting fluid while machining

A)Magnesium
B)Low carbon steel
C)Copper
D)Brass
E)Aluminium

Question 35

Out of the following tools which one is expected to have highest carbon percentage

A)Crowbar
B)Ordinary file
C)Circular saw
D)Pliers
E)Wrenches

Question 36

For welding of non-ferrous materials which of the following is preferred?

A)Microwave frequency voltage
B)Low frequency ac
C)High frequency ac
D)Direct current
E)Induction heating

Question 37

As far as machinability is concerned, which of the following will be considered to be most inferior alloy?

A)Malleable cast iron
B)Parting off
C)Monel metal
D)Gun metal
E)Bearing bronze

Question 38

Precision is

A)The ability of a measuring device to detect small differences in a quantity being measured
B)Agreement of the result of a measurement with the true value of the measured quantity
C)The ability of an instrument to reproduce same reading under identical conditions
D)The repeatability of a measurement process
E)Error of judgment in reading on observation

Question 39

In centrifugal castings, the cores are generally made of

A)Green sand and molasses
B)Plastic
C)Wax
D)Cores are not used
E)Plaster of paris

Question 40

In orthogoual cutting of metals the cutting edge is

A)Perpendicular to the direction of tool travel
B)Perpendicular to the work piece
C)Perpendicular to the shear plane
D)Perpendicular to the axis of cutting tool
E)None of the above

Question 41

Hardest abrasive is

A)Aluminium oxide
B)Silicon carbide
C)Boron carbide
D)Diamond
E)Tungsten oxide

Question 42

Riser is generally located

A)near the parting line
B)on the upper most section of the casting
C)Parting off
D)opposite to the pouring end
E)near the deepest section of the mould

Question 43

Which of the following test can be used to detect surface cracks in the welding of non-magnetic alloys?

A)Fluorescent test
B)Gamma ray test
C)X-ray test
D)Magnaflux test
E)Any of the above

Question 44

Which of the following process has the lowest rate of metal removal?

A)Electron beam machining
B)Electro discharge machining
C)Abrasive jet machining
D)Electro chemical machining
E)Chemical machining

Question 45

Which of the following machine is likely to be extensively used in a workshop manufacturing wire nails?

A)Lathe
B)Broaching machine
C)Drilling machine
D)Power press
E)Cold heading machine

Question 46

Shearing strain in the chip at shear plane is

A)tan (? + ?) + cot ?
B)tan (? - ?) - tan ?
C)Infinite clearance
D)tan (? - ?) + cot ?
E)tan (? - ?) + tan ?

Question 47

Which of the following is the most common bond used in grinding wheels?

A)Shellac bond
B)Pakelite bond
C)Parting off
D)Rubber bond
E)Vitrified bond

Question 48

The grain size of moulding sand is expressed in terms of

A)Mean grain diameter
B)Seive number
C)Grain diameter
D)Grain density
E)Grain fitness number

Question 49

Refractory metals are

A)Those which can be cast in the form of bricks
B)Those which reflect heat
C)Those which have melting point above 1950°C
D)Those which absorb heat
E)Those do not malt in a normal furnace

Question 50

Press die life is gauged by

A)loss in weight
B)amount of burr produced
C)change of colour
D)Any of the above
E)Parting off