Category: Machine Tools & Machining Objective Questions

Machine Tools Multiple Choice Questions on “Lathe : Mandrels and Its Types-1”.

1. Mandrels are used for holding solid work piece.
a) true
b) false
Answer: b
Clarification: This is false. Mandrels are used for holding hollow work piece.

2. Which of the following is not true?
a) the work piece must have their bores machined accurately
b) the mandrels are to be located before the centres
c) mandrels are used for turning concentric
d) none of the mentioned
Answer: b
Clarification: All the sentences are true except one which says that the mandrel are to be located before the centres. The mandrels should be located in between the centres.

3. Mandrels are driven by_____
a) catch plates
b) carriers
c) catch plates and carriers both
d) none of the mentioned
Answer: c
Clarification: Both are used to drive the mandrels. Catch plates are either screwed or bolted to the nose of the tailstock spindle while the carriers consist of a cast iron or forged steel body.

4. The diameters at the beginning are slightly smaller and flattened.
a) true
b) false
Answer: b
Clarification: This is false. The diameters at the end are slightly smaller and flattened to provide effective gripping surface of the lathe dog set screw..

5. Why gripping mandrels are made of high carbon steel?
a) to avoid distortion
b) to avoid wear
c) both to avoid distortion and wear
d) none of the mentioned
Answer: c
Clarification: The gripping mandrels are made of high carbon steel to avoid both distortion and wear. Along with this, the gripping power of this mandrels is not much.

6. Less common but very often used method is_____
a) parallel mandrel
b) threaded cone mandrel
c) both parallel mandrel and threaded cone mandrel
d) none of the mentioned
Answer: c
Clarification: There are several types of mandrels in use depending upon the specific requirements of the job. Less common but very often used is the parallel mandrel and the threaded cone mandrel.

7. The mandrels are driven into the work by tapping by_____
a) copper hammers
b) lead hammers
c) copper hammer and lead hammer both
d) none of the mentioned
Answer: c
Clarification: The mandrels are driven into the work by tapping with copper and lead hammers or by an arbor press or by mandrel press.

8. Which of the following is not true?
a) the mandrels are used depending upon the specific requirements of the job.
b) the gripping power of mandrels is very high
c) effective gripping surface of the lathe dog set screw is done
d) none of the mentioned
Answer: b
Clarification: All mentiones sentences are true except one which says that the gripping power of the mandrel is very high. The gripping power of the mandrels is not much.

9. Which of the following is the type of mandrels?
a) plain mandrels
b) stepped mandrels
c) collar mandrels
d) all of the mentioned
Answer: d
Clarification: All of mentioned are the types of mandrels. Apart from these other types of mandrels are also there like expansion mandrel, gang mandrel and so on.

10. Turning a job on mandrel should be with heavy cuts.
a) true
b) false
Answer: b
Clarification: This is false. Turning a job on mandrels should be with light cuts.

11. Which of the following mandrels are most commonly used?
a) plain mandrels
b) stepped mandrels
c) collar mandrels
d) none of the mentioned
Answer: a
Clarification: The plain mandrels are most commonly used. It is also known as simple mandrel.

12. Plain mandrels are used where large number of identical work pieces having standard size holes are required to be mounted.
a) true
b) false
Answer: a
Clarification: It can be easily understood from definition of the plain mandrels. In this mandrel, the size of the mandrel is indicated at the flat end portion of the mandrel.

13. The difference in diameter is_____ mm per 100 mm length in case of the plain mandrels.
a) 1to 2
b) 4 to 5
c) 8 to 10
d) 10 to 12
Answer: a
Clarification: The difference in diameter is 1 to 2 mm per 100 mm length in case of the plain mandrels. The taper is provided for proper gripping of the work.

14. Plain mandrel is suitable for_____ size of bore.
a) only one
b) two
c) more than two
d) none of the mentioned
Answer: a
Clarification: Plain mandrel is suitable for only one size of bore. For different sizes of holes in workpieces different diameters of mandrels are used.

15. In plain mandrels, length varies from_____ mm.
a) 15 to 90
b) 125 to 300
c) 55 to 430
d) 235 to 660
Answer: c
Clarification: In plain mandrels, length varies from 55 to 430 mm. The body of this mandrel is slightly tapered.

Machine Tools Multiple Choice Questions on “Pillar Drilling Machine”.

1. Distance between the table and drill is_____ in pillar drill machine as compare to table top drill machine.
a) small
b) high
c) same
d) none of the mentioned
Answer: b
Clarification: The distance between the table and drill is more in pillar drill machine. Pillar drill uses a column and base along with drill making a sturdy as well as safe place to drill materials like wood and so on.

2. Which of the following is not true for pillar drill machine?
a) it is an extension of table top drill machine
b) it is very strong
c) it is not rigid
d) none of the mentioned
Answer: b
Clarification: All mentioned sentences are true except one which says that it is very strong. This type of machine is not very tough or strong.

3. Which type of motion is possible for table in pillar drill machine?
a) only swivel
b) only upward and downward
c) all swivel, upward and downward
d) none of the mentioned
Answer: c
Clarification: These all motions of table is possible in pillar drill machine in order to accommodate with job.

4. The pillar drill machine can perform maximum______ mm of diameter job.
a) 10
b) 100
c) 20
d) 200
Answer: c
Clarification: Generally, this machine cannot perform more than 20 mm diameter job. It is used for job below 20 mm diameter.

5. Pillar drill machine has a small tubular column.
a) true
b) false
Answer: b
Clarification: This is false. This machine has a long tubular column.

6. In pillar drill machine, there may be chances of vibration.
a) true
b) false
Answer: a
Clarification: In this machine chances of vibrations are there as the column job is not very rigid.

7. What is the maximum power that we can expect in pillar drill machine?
a) 0.5 Kw
b) 1.1 Kw
c) 5.5 Kw
d) 11.1 Kw
Answer: b
Clarification: As per the design, mechanism and performance, maximum 1.1 Kw power can be expected.

8. The pillar drill machine can perform______ work.
a) light
b) heavy
c) both light and heavy
d) none of the mentioned
Answer: a
Clarification: This machine is ordinary machine, not made for specific purpose or special task and generally used only for light work.

9. Which of the following is true for pillar drill machine?
a) it is taller
b) it can be mounted or fitted on ground or any other foundation
c) for the production of one or two pieces of light work, this can be used
d) all of the mentioned
Answer: d
Clarification: All sentences are taller. It is taller looks like a pillar that’s why this machine is known as pillar machine. It can be fixed on any base and only used for producing light work.

10. Which of the following is not true for pillar drill machine?
a) it looks like a pillar
b) the table is movable
c) it is not used for mass production
d) none of the mentioned
Answer: d
Clarification: All the sentences are true. As the name pillar machine itself suggests that it looks like pillar. Its table can move in order to accommodate with the job requirements. Its ordinary machine, not used for mass production.

Machine Tools Multiple Choice Questions on “Cutting Parameters of Drill”.

1. Which of the following are the cutting parameters used in drill?
a) cutting speed
b) feed
c) depth of cut
d) all of the mentioned
Answer: d
Clarification: All are the cutting parameters used in drill. Apart from these parameters, machining time, metal removal rate are also cutting parameters which are used in drill.

2. Which of the following is considered as the peripheral speed of the drill?
a) cutting speed
b) feed
c) depth of cut
d) none of the mentioned
Answer: a
Clarification: This is the definition of cutting speed. If you know the diameter of the drill and rpm of the drill, you can easily calculate the cutting speed.

3. Cutting speed generally express in_____
a) meter
b) meter/minute
c) meter*minute
d) none of the mentioned
Answer: b
Clarification: Cutting speed is simply a speed. So, its unit should be match with speed’s unit.

4. Formula for cutting speed is______
d=diameter of drill in mm, n=rpm of drill.
a) (d*n)/1000
b) (3.14*d*n)/1000
c) 3.14*d*n
d) none of the mentioned
Answer: b
Clarification: Though cutting speed is peripheral speed the distance covered through it must be equal to 3.14*d. N is rpm and 1000 is there as we are measuring it in mm.

5. The ______ of a drill is the distance the drill moves into the work at each revolution of the spindle.
a) depth of cut
b) feed
c) cutting speed
d) none of the mentioned
Answer: b
Clarification: This is the definition of feed. It is a distance/revolution.

6. The feed may be expressed in______
a) mm/revolution
b) mm*revolution
c) mm
d) none of the mentioned
Answer: a
Clarification: As per its definition, feed is the distance per revolution. So its unit should be match with this formula..

7. ______ is equal to half the diameter of the drill used.
a) feed
b) depth of cut
c) machining time
d) none of the mentioned
Answer: b
Clarification: This is the definition of depth of cut. Its simply a distance. Here one point is there, we always talk in terms of diameter in drill, never in terms of radius.

8. Depth of cut can be expressed in______
a) mm
b) mm/revolution
c) mm/minute
d) none of the mentioned
Answer: a
Clarification: It is simply a distance and so its unit should be match with distance’s unit.

9. The formula for depth of cut is______
d=diameter of the drill.
a) d/4
b) d/2
c) d
d) 2d
Answer: b
Clarification: Depth of cut is equal to half the diameter of the drill used. So if d is the diameter of drill then its formula must be equal to d/2..

10. If s2=feed per revolution, s1=feed per minute, n=rpm.
Which of the following is mathematically right?
a) s1=s2*n
b) s2=s1*n
c) s1*s2=n
d) none of the mentioned
Answer: a
Clarification: It can be solved by equating units both sides. Left side unit = feed/minute and Right side unit = feed / revolution * revolution/minute. So overall unit of right side = feed/minute. So, left side unit=right side unit.

11. Machining time is expressed in______
a) mm/minute
b) minute*minute
c) minute
d) none of the mentioned
Answer: c
Clarification: Machining time is simply a time. So its unit must be match with time’s unit.

12. If l=length of travel of the drill in mm, n=rpm of the drill, s= feed per revolution of the drill in mm. Then machining time can be given as_____
a) (l*n)/s
b) (l*s)/n
c) l/(n*s)
d) none of the mentioned
Answer: c
Clarification: L/(n*s)- This is the right formula for calculating machining time. Here l is expressed in mm, n is revolution/minute and s is expressed in mm. So by putting these all units in machining time’s formula we get the unit of the whole expression as minute. So our formula is right.

13. Metal removal rate can be given as_____
a) (mm*mm*mm)/min
b) (mm*mm*m)/revolution
c) mm/revolution
d) mm/minute
Answer: a
Clarification:
Metal removal rate = area of metal removed*rpm*feed/revolution and it equal to (3.14*d^2/4)*n*feed/revolution. From this, we can easily derive the expression.

Machine Tools Multiple Choice Questions on “Introduction to Milling”.

1. Milling machine is a machine tool that removes the metal as the work is fed against a rotating singlepoint cutter.
a) true
b) false
Answer: b
Clarification: Milling machine is a machine tool that removes the metal as the work is fed against a rotating multipoint cutter. Here, in milling machine multi point cutter should be used.

2. In milling machine, cutter rotates at high speed and removes metal at very high speed.
a) true
b) false
Answer: a
Clarification: It can be easily understood from its definition. This is the characteristic and advantage of milling cutters and that’s the reason why it is used more.

3. Milling machine can hold______ cutters at a time.
a) only one
b) only two
c) only three
d) none of the mentioned
Answer: d
Clarification: It can hold number of cutters at a time. Milling machine has multi point cutters.

4. Which of the following machine is superior to other machines as regards accuracy and better surface finish?
a) lathe
b) drill
c) shaper
d) milling
Answer: d
Clarification: Lathe, drill and shaper are general purpose machines. They are versatile while milling machine is special purpose machine.Special purpose machine are always superior to general purpose machines for a particular specific work.

5. Milling machines find wide application in production work.
a) true
b) false
Answer: a
Clarification: Milling machine is special purpose machine unlike lathe, drill and shaper. So, obviously it has higher accuracy and better performance. So it is largely used in production work for a specific purpose.

6. Which type of machining can be done by milling machine?
a) cutting keyways
b) slots and grooves
c) gears
d) all of the mentioned
Answer: d
Clarification: Cutting keyways,slots and grooves, gears all are the application of milling machine. It is a specific purpose machine..

7. Which of the following motion does a milling machine has?
a) vertical motion
b) crosswise motion
c) longitudinal motion
d) all of the mentioned
Answer: d
Clarification: Milling machine have all mentioned motions in order to perform various operation nicely. Due to this quality it has wider application and more accuracy..

8. For milling, the work is fixed on a table which controls the feed against the cutter.
a) true
b) false
Answer: a
Clarification: It can be easily seen from the working of the milling machine. Here the feed means relative movement of the tool or work.

9. Generally in workshop, column and knee type milling machine is used.
a) true
b) false
Answer: a
Clarification: This is the most general milling machine and used in workshop. It is further categorized as slab milling and face end milling.

10. Milling machine is designed for manufacturing a variety of tool room work.
a) true
b) false
Answer: a
Clarification: Milling machine are very versatile. Inspite of producing flat surfaces, it can also be used to dril, cut gear, bore and so on. It has wide applications.

Machine Tools Multiple Choice Questions on “Lathe : Cone Pulley drive”.

1. Which of the following are the advantages of cone pulley drive?
a) easy to maintain
b) can take up heavy load
c) positive drive when the back gear is in engagement.
d) all of the mentioned
Answer: d
Clarification: These all are the advantages of the cone pulley drive. It is stepped pulley mounted on the main spindle which is free to revolve.

2. Number of spindle speeds is limited to the number of steps
in the cone pulley drive.
a) true
b) false
Answer: a
Clarification: It can be easily seen from the definition of cone pulley drive. This cone pulley gets the drive from the main motor.

3. What does happen during the overload in the cone?
a) number of steps in cone pulley increases
b) belt slips off
c) nothing happens
d) none of the mentioned
Answer: b
Clarification: During the overload in the cone, the belt slips off so that no major damage happens to the lathe.

4. It doesn’t take time to change spindle speeds.
a) true
b) false
Answer: b
Clarification: This is false. In practical work, it takes time to change the spindle speed.

5. Cone pulley drive without back gear arrangement means_____
a) back gear in
b) back gear out
c) back gear neutral
d) none of the mentioned
Answer: b
Clarification: It can be easily seen from the definition of the back gear. The headstock having cone pulley drive is known as cone pulley headstock.

6. Cone pulley drive with back gear arrangement means_____
a) back gear in
b) back gear out
c) back gear neutral
d) none of the mentioned
Answer: a
Clarification: It can be easily seen from the definition of the back gear. The axis of this back gear shaft is parallel to the axis of the main spindle.

7. Which of the following mounted on the bush bearing?
a) speed motor
b) spindle
c) both spindle and speed motor
d) none of the mentioned
Answer: b
Clarification: As per the construction of lathe, spindle is fitted on the bush bearing. It is mounted in the headstock casting and a gear wheel called bull gear is keyed to it.

8. Stepped pulley mounted on the main spindle is fixed.
a) true
b) false
Answer: b
Clarification: This is false. Stepped pulley is free to revolve.

9. The back gear unit has a shaft, which carries _____
a) a gear
b) a pinion
c) a gear and a pinion both
d) none of the mentioned
Answer: c
Clarification: The back gear unit has a shaft, which carries a gear and a pinion. The number of teeth of the gear and a pinion on the back gear shaft corresponds to the number of teeth on the bull gear and the pinion on the cone pulley.

10. The axis of the back gear is_____ to the axis of the main spindle.
a) parallel
b) perpendicular
c) at any angle other than 0 and 90
d) none of the mentioned
Answer: a
Clarification: The axis of the back gear is parallel to the axis of the main spindle and the back gear is bought in engagement or disengagement with the cone pulley system by means of a lever.

11. A three-stepped cone pulley headstock provides three direct ranges of speeds.
a) true
b) false
Answer: a
Clarification: This is true. A three-stepped cone pulley headstock provides three direct ranges of speeds through the belt connection and with the back gear in engagement, three further ranges of reused speeds can be obtained.

Machine Tools Multiple Choice Questions on “Lathe : Mandrels and Its Types-2”.

1. Which of the following is not true in case of plain mandrel?
a) the body of the mandrel is heavily tapered
b) the taper is provided for proper gripping of the work piece
c) the size of mandrel is indicated at the flat end portion of the mandrel
d) none of the mentioned
Answer: a
Clarification: All the mentioned sentences are true except the one which says that the body of mandrel is heavily tapered. Actually, its body is just slightly tapered.

2. Stepped mandrels are used for turning______
a) collars
b) washers
c) odd sized jobs
d) all of the mentioned
Answer: d
Clarification: Stepped mandrels are used for collars, washers, odd sized jobs and so on. The stepped mandrel will have steps of different diameters to accommodate different workpieces.

3. Which of the following is not true about steeped mandrels?
a) it can have steps of different diameters
b) it can accommodate different work pieces having different sizes of holes
c) removal of mandrel is necessary each time
d) none of the mentioned
Answer: c
Clarification: Removal of mandrel is not necessary each time. Sometimes, it can accommodate work piece without removing the mandrel.

4. In collar mandrel, mandrels are provided with solid collars for turning work pieces having holes of small diameters.
a) true
b) false
Answer: b
Clarification: In collar mandrel, mandrels are provided with solid collars for turning work pieces having holes of large diameters.

5. Collar mandrel fits better than a solid mandrel of equal size.
a) true
b) false
Answer: a
Clarification: The construction of collar mandrel reduces its weight considerably and that’s the reason why it fits better than solid mandrel of equal size.

6. Which of the following mandrel is mostly used for work piece having internal threads?
a) stepped mandrel
b) collar mandrel
c) gang mandrel
d) none of the mentioned
Answer: d
Clarification: Answer should be none of the mentioned. Screw mandrel is mostly used for work piece having internal threads.

7. In screwed mandrel, the threads_____
a) are left handed
b) are right handed
c) may be left or right handed
d) none of the mentioned
Answer: c
Clarification: In screwed mandrel, the threads may be left or right handed. Screw mandrels are used for turning the external surfaces of screwed flanges, back plates of chucks etc.

8. Which of the following is not true for screwed mandrel?
a) the screw mandrel is threaded at one end with a collar
b) the work piece are screwed on to the threaded portion against the collar for machining
c) screw mandrels are used for turning the internal surfaces of screwed flanges, back plates of chucks etc
d) none of the mentioned
Answer: d
Clarification: All the mentioned sentences are true except the one which says that screw mandrels are used for turning the internal surfaces of screwed flanges, back plates of chucks etc. Actually, screw mandrels are used for turning the external surfaces of screwed flanges, back plates of chucks etc.

9. P mandrel consists of a solid one attached to one end and a sliding cone and adjusting nut on the other end. Identify P.
a) plain mandrel
b) stepped mandrel
c) cone mandrel
d) none of the mentioned
Answer: c
Clarification: This is the property of cone mandrel. This type of mandrel is suitable for holding workpieces of different diameters.

10. The cone should be more tightened upon the work piece in cone mandrels.
a) true
b) false
Answer: b
Clarification: This is false. The cone should not be tightened too much over the work piece otherwise the outer surface the outer edge may get spoiled.

11. Which of the following is the part of gang mandrel?
a) fixed collar
b) movable collar
c) nut
d) all of the mentioned
Answer: d
Clarification: All of the mentioned are the parts of the gang mandrel. A set of hollow workpieces are mounted on this mandrel and tightened with a nut. The friction between the sides of the work and collar drives the work without any slippage.

12. In expansion mandrel, how many longitudinal slots are there?
a) 1
b) 2
c) 3
d) 4
Answer: c
Clarification: 3 longitudinal slots are there in expansion mandrel. This type of mandrels are very useful in repair workshops where the diameters of workpieces differ frequently from standard sizes.

13. P mandrel is often provided with adapters or sleeves of different diameters to fit a wide variety of work piece bores. Identify P.
a) gang mandrel
b) expansion mandrel
c) collar mandrel
d) none of the mentioned
Answer: b
Clarification: Expansion mandrel is often provided with adapters or sleeves of different diameters to fit a wide variety of work piece bores. The expansion mandrel has a tapered pin driven into a sleeve which is parallel outside and tapered inside.

14. Expanding mandrels are also available with taper shank.
a) true
b) false
Answer: a
Clarification: Expanding mandrels are also available with taper shank to suit the spindle taper of the lathe.

15. Expanding mandrels can be______ at one end.
a) plane
b) threaded
c) either plane or threaded
d) none of the mentioned
Answer: c
Clarification: Expanding mandrels can be plane or threaded at one end. Expansion mandrels are also known as expanding mandrels and this is the property of expansion mandrels.