For cutting taper threads on a lathe the cutting tool is set..........
a) Perpendicular to taper surface b) Half the taper angle
c) Perpendicular to lathe axis. d) Half the angle of thread
For case hardening the first stage is carburizing. By carburizing it is meant:-
a) Increasing the percentage of carbon of the steel piece
b) Increasing the percentage of carbon of the core of the piece
c) Increasing the percentage of carbon on the surface
d) Decreasing the percentage of carbon of the steel piece.
Which of the following statements is correct:-
a) Interchangeability of parts may be obtained by adopting the systems oflimits&fits.
b) The BIS system oflimits&fils does not give the desired fit.
c) Interference fit is always designed with a positive clearance
d) Transition fit is always specified with a negative clearance.
Mass produced components should be interchangeable. One of the following is most important factor required to achieve the interchangeability in mass production:-
a) Dimensional accuracy
c) Geometrical accuracy
d) Surface finish
The external surface of the pan made of mild steel can be hardened by-
a) Tempering b) Case hardening c) Normalising d) Hardening
Which one of the following statements about programming of NC machine is curret
a) Programming is only possible on central server
b) Programming can be entered on control panel and can be read from a tape
c) Modification of the programme on the control panel is not possible
d) Entering the programme is only possible directly on the control panel
The process of producing a component with tough and ductile core and a hard outer surface is known as:-
a) Hardening b) Tempering c) Annealing d) Case hardening
If the dimension of a component is finished within the limits of size, then it will be--
a) Minimum size b) Acceptable size c) Basic size d) Rejected size
One component of C50 steel is heated to 830°C, soaked at it for some time and then quenched m oil. Again it is heated to 600°C and quenched in oil. What is the name of the process,-
a) Annealing b) Normalising c) Hardening & tempering d) Case hardening
A CMC lathe is programmed and set to turn a diameter of 50 mm, but on trial run the diameter is found to be 50.01 mm. which one of the following will ensure correct diameter during production:-
a) Increase the tool offset by 0.1 mm b) Decrease the tool off-set by 0 05 mm
c) Increase the tool offset by 0.05 mm d) Decrease the tool off-set by 0.01 Z
h£ «u7?f heati"8 StCel l° ab°Ut 4°° ab0VC me critical temperature and cooling
it in still air to room temperature is known as-- ^
a) Hardening b) Normalising c) Annealing d) Case hardening
The point to point is the simplest form of NC. The operation done in this system is:-
a) Drilling b) Boring c) Straight line milling d) Any of these
Under the terminology of the IS system of limits the term "tolerance" is defined as the difference between the:-
a) Maximum limit and the basic size
c) Maximum limit and Minimum limit
b) Minimum limit and the basic size
d) Actual size and the basic size.
Which one of the following is the solid carburizing material?
a) Petrol b) Ammonia c) Kerosene
Which one of the following is NOT the advantage ofCNC machine?
a) Reduces inspection time
c) Higher initial cost
b) Reduces tooling time
d) Higher rate of production
CNC machines are not normally operated, but they are controlled by means of a:-
d) Plug board system
The purpose of annealing is to..................
a) Improve machinabihty
c) Increase hardness
b) Improve magnetism
d) Increase toughness
Heat treatment of metals is necessary to_
a) Make a good appearance on the component
b) Produce certain desired property
c) Increase strength of metal
d) Make the metal rust proof
A point to point control system is suitable only for one of the following application:-
a) Milling profile b) Turning c) Drilling d) Grinding
CNC lathe machines have built in co-ordination measuring system. The zero position
the co-ordinate system is called_.
a) Reference point b) Programme zero point
c) Machine zero point d) Work zero point
In M - function - M - 03 means:-
a) Spindle rotation (CW) b) Spindle rotation (CCW)
c) Coolant on d) C oolant off
In a single spindle automatic lathe for bar work has a capacity of <D25mm (which means
that the size of round bar that can be hold is O 25mm) If we want to load square rod in
this automatic lathe the maximum size of the square rod can be loaded is_
a) 17.67 mm b) 312.5 mm c) 25 mm d) 5 mm
The hardening temperature^of H.S.S tool is:-
On which unit is the tool setting done on NC machine:-
a) On special device away from the machine
b) On machine it while other operations are being performed
c) On NC machine during idle time
d) On the presetting device
Single spindle auto lathe for bar work has its slide movements controlled by cams for the
production of a typical component the cams are fixed on the cam holders
three cam shafts of the machine. The number of revolutions made by the cam shafts will
be equal to:-
a) Number of components produced per hour.
b) 1/3 rpm of the main spindle
c) Thrice the number of components produced per minute
d) rpm of the main spindle
The direction of the predominant surface pattern ordinarily determined by the production
method is known as>
a) Lay b) Roughness c) Waviness d) Surface texture
Lead is the metal used for balancing weight during lathe face plate work. The reason for
this is that lead is_.
a) Most ductile b) Heaviest c) Toughest d) Most elastic
Which one of the following operations is NOT automatic on a single spindle auto lathe?
a) Bar loading b) Bar feeding
c) Coolant circulation d) Collet opening & closing
A phosphor bronze split bearing bush is to be finish machined on a centre lathe, the
slitting of the bush into two halves is done....................
a) Before beginning to rough turn and bore the pot
b) After rough oversize turning the collars and the step without boring
c) After rough oversize turning the collars, step and rough boring
d) After completely finish turning the collars, step and finish boring.
While measurine zero offset in CNC machine the machine should be in:-
a) MD1 mode b) Jog modec) Automatic mode d) Preset mode
When machining irregularly shaped work held on face plate, counter balancing is done by clamping weights.
This is done:-
a) Before mounting the face plate on the spindle nose.
b) After mounting the face plate on the spindle nose and revolving work at the slow rpm
c) After mounting the face plate on the spindle nose and keeping spindle in neutral position
d) After taking the rough cut.
Which one of the following collets is suitable to hold a 25 mm diameter rod accurately
in a single spindle auto Jathe?
a) Draw in collet
c) Dead length collet
b) Push type collet
d) Master collets with pads
CAD and CAM are related througrr-
a) NC tapes
c) Parts production testing
b) Automatic tools
d) Common data base
Automatic lathes are capable of performing preset cycle of operation, the number of
components produced per cycle of operations depends on:-
a) The number of toolings
b) The design of cams controlling the slide movements
c) The number of spindles on the machine
a) The range of speeds and feeds
A multi start square thread is to be cut on a lathe with single point tool. Which one of the
following angles of the tool is to be ground by taking into consideration, the thread helix
a) Side relief b) Front clearance c) Side rake d) Side clearance