MACHINIST GRINDER theory jan 17 sem 3 questions

MACHINIST GRINDER theory  jan 17 sem 3 questions

The silicon carbide abrasive is chiefly used for grinding...........
a. Cemented carbide | b Cast iron c. Ceramic d.. All of these

The grinding operation is a................
a. Shaping operation   b. Forming operation   c. Surface finishing operation    d. Dressing operation

Glazine in grinding wheels_cutting capacity..............
a. Has no effect on       b.Decrease     c. Increase    d. None of these

For fast removal of materials during grinding, a-grinding wheel is.................
a. Course grained    b. Medium grained    c. Finegrained   d. None of these

In cemreless grinding, work place centre will be.............
a. Above the line joining the two wheel centres
b. Below the line joining the two wheel centres
c. On the line joining the two wheel centres
d. At the intersection of the line joining the wheel centres with the work place plane

grinding wheel becomes glazed (i.e. cutting edge takes a glass-like appearance) due to..........
a   Wear of bond      b.Wear of abrasive    c   Breaking of abrasive grains     d. Cracks on gnndmg wheel

A....................grinding wheel is used to grind soft materials..............
a. Course grained   b.Finegrained c. Medium grained d. None of these

The abrasive recommended for grinding materials of low tensile strength is.................
a. Silicon carbide     c Sandstone   b. Aluminium oxide     d.  Diamond

The'process of changing the shape of grinding wheel as it becomes worn due to breaking away of the abrasive and called.........
a. Truing    b. Dressing   c. Facing   d. Clearing

The method of centre less grinding used to produce taper is...........
a.  In-feed grinding     b.  End feed grinding   c. Through feed gnnding d. None of these

Thread grinding requires work speed from.............
a. 1 to 3 m/min       b. 5to10m/mm       c. 10 to 14 m/min      d 14to20m/min

The grinding wheel speed (surface Speed in m/min) usually varies from............
a.  500 to 1000       b.  1500 to 2000       c. 1000 10 1500           d. 2000 to 2500

The in-feed grinding is used to................
a. Produce tapers                                     b. Grind shoulders and formed surfaces 
c. Grind long, slender shafts or bars    d. All of these

Fixtures are used-
a.  For holding and guiding the tool in drilling, reaming or tapping operations
b. For holding the work in milling, grinding, planing, or turning operations
c. To check the accuracy of workpiece
d. None of the above

The work or surface speed for cylindrical grinding varies from-
a 5tol0m/min
b.  10 to 20 m/min
c. 20 to 30 m/min
d. 40 to 60 m/min

Thejjerfoimancc of grinding wheel is evaluated in terms of grinding ratio (G) which is given
by the ratio of..................
a.  The volume of material required to the volume of wheel wear
b. The volume of wheel wear to the volume of material required
c. Both(a)&(b)
d. None of the above

In order to grind soft material.............
a. Coarse grained grinding wheel is used
b. Fine grained grinding wheel is used
c. Medium grained grinding wheel is used
d. None of above

When the finishing is more important than the dimension then................
a. Honing operation is carried out for finishing
b. Lapping operation is carried out for finishing
c. Grinding operation is carried out for finishing
d. All of the above

A device, in which a component is held and located for a specific operation and bushes are
integrated that guide the tool, is called as.............
a. Jig            b. Both (a) and (b)    b. Fixture         d. None of these

The device which place the workpiece in the same position, in jig and fixture, cycle after
cycle is called as..............
a. Placing device    b. Locating device     c. Fixing device     d. Positioning device

V-blocks (Vee locators) are used for clamping as well as locating when faces are inclined
a. 3°      b. 9°      c. 12°          d. 3°

What kind of material can you grind with aluminum oxide grinding wheels?
a. Only aluminum.
b. Any type o f metal.
c. Any metal with a yellow, gold or amber hue.
d. Ferrous or iron-based materials, like iron or steel.

How much of a gap should there be between the work rest and the face of the grinding wheel?
a. 1/8" or less    b. 1/4"     c. Not less than 1/8"     d. 1"

The wheel hole diameter and the grinder arbor size are not the same. What can you do to make the wheel workable?
a. The wheel is not compatible with the grinder. Do not install it.
b. Go ahead and install it. even if you have to force the wheel onto the spindle.
c. Screw on the wheel nut especially tight.
d. Both(b)&(c)

The branch of science dealing with wear, tear and lubrications is called-
a. Ergonomics      b. Mechatronics   c. Tribology     d. None of these

What is the cause of a grinding wheel becoming glazed in a grinding machine?
a. Grinding wheel's grade is too soft
b. Grinding wheel's grade is too large
c. Feed and traverse are less
d. Grinding wheel's speed is too high and work speed is low

You have to select a grinding wheel with suitable abrasive to grind glass. What is the type of abrasive you w ill select?
a. Diamond      b. Quartz   c.  Emery    d. Silicon carbide

Which one of the following features, refers to vitrified bond wheels?
a. Used for longer period due to dense structure
b. Used for longer period due to an elastic structure
c. Not sensitive to shocks and pressure
d. Suitable for wet and dry grinding

For cylindrical grinding a small diameter work with fairly large wheel, which among the following grades of wheel should be used?
a. Soft         b. Hard      c. Medium          d. Very soft

As per rndian Standards the 'K* grade of grinding wheel comes under the group-
a.   Soft      b. Hard      b. Medium     d. Vervhard

What will happen if the job is loosely fitted between centres in cylindrical grinding?
a. The job will be out of round b.  The job will be thrown out
c. The job will be oversized d. The job will not rotate

Which one of the following cutting fluids is used during grinding mild steel?
a. Mineral oil     b.  Soluble oil    c. Non-synthetic cutting oil     d. Paraffin

Grinding fluids are used to-
a. Reduce the friction between the wheel face and the job
b. Wash away chips
c. Prevent loading of wheel
d. All of the above

The symbol conventionally used for resinoid bond
a. V  b. R  c. B  d. E

As per Indian standards the M grade of grinding wheel come under the group-
a-  Soft    b. Hard   c. Medium   d   Very hard

Which one of the following instruments is used to cheek the concentricity of the outside
a. Vernier caliper    b.  Dial test indicator   c. Outside micrometer    d. Dial calliper

To convert the linear motion of the plunger of a dial test indicator to the rotary motion of the pointer, which one of the following mechamsms is used?
a. Quick return mechanism b. Screw thread mechanism
b. Rack and pinion mechanism d. Hydralic mechanism

The principle of universal bevel protractor is similar to of- ^
a. Verniar bevel protractor     b.  fixed gauge
c. Depth micrometer d. Dial test indicater

A flange micrometer is used to measure- Addendum of the gear
a. Outside diameter of a gear     b. Chordal tluckness of gear   c. Addendum of the gear   d. None of these

While laying out, the vernier height gauge must be used onthe^ ^
a. Surface plate     d  Any flat surface    c. Machine bed    d. VeeblocK

On which part of the vernier height gauge, are the main '
a. Vernier plate     b.  Fine adjusting unit     c.  Base      d. Beam

Rotation to the workpiece  plain cylindrical centre type grider is given by.............
a. Live centre     b. Steady centrec.     c. Driving plate   d. None of these

To reverse the direction of sliding table in a cylindrical centre type grinder. _
provided in the machine. c   Bonds in the wheel
a.  Spindle    b. Trip dogs     c.  Bonds in the wheel    d   None of these

In centreless grinding, the workpiece is advanced by-
a. Force exened by the regulating wheel   b. Manually   c. Automotive dnve    d. None of these

How will you ensure the correctness of internal radius?
a.  By radius gauge
b. By seating a round ball  bearing
c.  By grinding an internal radius tool equal to the radius of job to do the operation
d.  By template

A rough turning tool is ground by hand on a pedestal grinder . A after grinding it is observed
that the grounded of the tool are concaved- Which of the following statements is the cause for this defect?
a. Tool rest not set to the required angle
b. Too! held in one position only against the wheel
c. Surface speed of the grinding wheel is not as specified
d. The grinding is carried out on a peripheral grinding wheel

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