Category: Machine Tools & Machining Objective Questions

Machine Tools Multiple Choice Questions on “Drilling Operation-1”.

1. A hole is being drilled with 5 mm drill at a feed of 0.1 mm/revolution and rpm is 200. Calculate the metal removal rate (m) in mm³/minute.
a) 392.5
b) 785
c) 1570
d) none of the mentioned
Answer: a
Clarification: Here, we have the value of diameter, feed and rpm. So, from the formula, m= ( 3.14*d*d*f*n) / 4, we can easily get the value of metal removal rate.

2. If drill is 2.5 mm, feed is 0.35 mm/revolution and metal removal rate is 40 mm³/minute. Then find out the value of rpm.
a) 46.6
b) 23.3
c) 93.2
d) 11.65
Answer: b
Clarification: From the formula, m= ( 3.14*d*d*f*n) / 4. From this formula, we can easily calculate rpm. Rpm means revolution per minute.

3. If drill is 5.5 mm, metal removal rate is 65 mm³/minute and rpm is 130.Then find the value of feed in mm/revolution.
a) 0.02
b) 0.2
c) 0.04
d) 0.4
Answer: a
Clarification: Feed is the distance the drill moves into the work at each revolution of the spindle. From the formula, m= ( 3.14*d*d*f*n) / 4, we can easily calculate feed.

4. If metal removal rate is 120 mm³/minute, rpm is 105 and feed is 0.1 mm/revolution. Then find the value of drill in mm.
a) 14.6
b) 3.8
c) 7.6
d) 1.9
Answer: b
Clarification: From the formula, m= ( 3.14*d*d*f*n) / 4, we can calculate the value of drill.

5. If value of the diameter of the drill (d2) = 10mm, then find the value of the depth of cut (d1).
a) 5
b) 10
c) 20
d) none of the mentioned
Answer: a
Clarification: Value of diameter of the drill is always twice to that the value of the depth of cut. From the formula, d1= d2/2.

6. The diameter of the drill is 15 mm and rpm of drill is 5. Find the value of cutting speed in meter/minute.
a) 235.5
b) 0.2355
c) 0.075
d) 75
Answer: b
Clarification: From the formula, cs = (3.14*d*n) /1000. Cutting speed is the peripheral speed of the drill.

7. Rpm is 10 and feed per revolution (f2) is 5. Then find the value of feed per minute (f1).
a) 2
b) 4
c) 1
d) none of the mentioned
Answer: d
Clarification: Rpm = f1/f2. Here rpm=10 and f2=5. So value of f1 should be 50.

8. If depth of cut is 20 mm, then find the value of diameter of the drill.
a) 10
b) 20
c) 40
d) none of the mentioned
Answer: c
Clarification: Depth of cut=diameter/2. It is simply a distance.

9. Feed per minute (f1) is 20 and rpm (n) is 5. Then find the value of feed per revolution (f2).
a) 2
b) 4
c) 1
d) 0.5
Answer: b
Clarification: Rpm = f1/f2. Here f1=20 and n=5. So, f2 should be 4.

10. If t=2minute, n=2rpm and s=5 mm. Then find the value of l. t=machining time in minute, l=length of travel of the drill in mm, n= rpm of the drill and s=feed per revolution of the drill in mm.
a) 5
b) 10
c) 20
d) none of the mentioned
Answer: c
Clarification: From the formula, t= l / (n*s). Here t=2, n=2 and s=5. Put all these values with their units in the mentioned equation,you will easily get the answer as 20 mm.

11. If d=2, n=1 and f=2. Then find the value of m. d= diameter of drill in mm, n=rpm, f=feed per revolution in mm and m=metal removal rate in mm³/minute.
a) 3.14
b) 6.28
c) 12.56
d) none of the mentioned
Answer: b
Clarification: From the formula, m= (3.14*d*d*n*f) / 4, we can easily get the value of m. Metal removal rate means the rate at which the metal is removed during the operation.

12. If d=2, n=2 and m=3. Then find the value of f. d= diameter of drill in mm, n=rpm, f=feed per revolution in mm and m=metal removal rate in mm³/minute.
a) 0.238
b) 0.477
c) 0.119
d) none of the mentioned
Answer: b
Clarification: From the formula, m= (3.14*d*d*n*f) / 4, we can easily get the value of feed. Feed may also be expressed as feet per minute or mm/minute.

13. If m=5, n=2 and f=3. Then find the value of m. d= diameter of drill in mm, n=rpm, f=feed per revolution in mm and m=metal removal rate in mm³/minute.
a) 1.03
b) 1.065
c) 0.266
d) none of the mentioned
Answer: b
Clarification: From the formula, m= (3.14*d*d*n*f) / 4, we can easily find the value of m.

14. If cs=0.942 and d=60, then find the value of n. d=diameter of drill in mm, n=rpm and cs=cutting speed in mm/minute.
a) 15.7
b) 15700
c) 5
d) 5000
Answer: c
Clarification: From the formula, cs = (3.14*d*n) /1000, we can easily find value of n. N means rpm-revolution per minute. It is an important term in any operation.

Machine Tools Multiple Choice Questions on “Column and Knee Type Milling Machine”.

1. In horizontal type universal column and knee type of milling machine, the table is placed on the knee-casting which in turn is mounted on the _____ slides of the main column.
a) horizontal
b) vertical
c) 45 degree inclined to both plans
d) none of the mentioned
Answer: b
Clarification: As per the construction of this machine. This is true for horizontal type machine. In plain and vertical type machine arrangement may be different.

2. The knee is ______ adjustable on the column in horizontal column and knee type milling machine.
a) horizontally
b) vertically
c) can’t say anything
d) none of the mentioned
Answer: b
Clarification: The knee is vertically adjustable on the column in horizontal machine so that table can move in vertical direction.

3. In this machine, the table can be moved ______
a) only up
b) only down
c) both up and down
d) none of the mentioned
Answer: c
Clarification: The table can be moved up and down to accommodate work of various heights.

4. In this horizontal column and knee type machine, cutter rotates about _____ axis.
a) horizontal
b) vertical
c) 45 degree inclined to both plans
d) none of the mentioned
Answer: a
Clarification: In this machine, cutter rotates about horizontal axis that’s the reason why it is known as horizontal column and knee type machine.

5. The column and knee type milling machines are classified according to_______
a) various methods of supplying power to table
b) different movements of table
c) different axis of rotation of spindle
d) all of the mentioned
Answer: d
Clarification: As per the classification of this machine, these are the aspects in which machine can be classified. These machines are mostly used in workshop.

6. In a universal milling machine, table of the machine may be swiveled about a vertical axis, which helps in _____ milling.
a) helical
b) cam
c) both helical and cam
d) none of the mentioned
Answer: c
Clarification: It helps in helical milling, cam milling and several other milling. This universal milling is also suitable drilling and tapping.

7. Which of following part of these machines is swivel base?
a) top
b) bottom
c) middle
d) none of the mentioned
Answer: c
Clarification: As per the construction of this machine, bottom part is swivel base on which stands the column.

8. Which part of this machine has transverse motion?
a) top
b) bottom
c) middle
d) none of the mentioned
Answer: b
Clarification: As per the construction of this machine,bottom parts has traverse motion. Bottom part can be moved toward or away from the column.

9. Which part of this machine has longitudinal motion?
a) top
b) bottom
c) middle
d) none of the mentioned
Answer: a
Clarification: The top part of this machine has longitudinal motion in the guideways machined in the swivel base.

10. Guideways are machined on the _____ of the knee.
a) top
b) middle
c) bottom
d) none of mentioned
Answer: a
Clarification: Guide ways are machined on the top of the knee. Guideways means a track or path along with something moves.

11. Which of the following part of machine is a cross slide?
a) top
b) middle
c) bottom
d) none of mentioned
Answer: c
Clarification: Bottom part of machine is a cross slide. This part can move towards or away from the column.

12. The top part of this machine is mounted on the swivel base.
a) true
b) false
Answer: a
Clarification: The top part of the machine means actual table and this table is located on the swivel base.

13. The cutter is mounted on the arbor.
a) true
b) false
Answer: a
Clarification: The cutter is mounted on the arbor with the purpose of fitting it into the spindle of the mechanism.

14. The knee is capable of being moved up and down over the guideways formed at the _____ of the column.
a) front
b) back
c) can’t say anything
d) none of the mentioned
Answer: a
Clarification: The knee is capable of being moved up and down over the guideways formed at the front of the column.This motion helps in accommodating jobs of varying heights and also giving depth of cut.

15. The machine consists of a light base on which stands the column.
a) true
b) false
Answer: b
Clarification: The machine consists of a rigid base on which stands the column. The column houses the drive motor and speed mechanism in addition to providing support for spindle and spindle bearings.

Machine Tools Multiple Choice Questions on “Headstock”.

1. Headstock is a flexible unit.
a) true
b) false
Answer: b
Clarification: This is false. Headstock is a fixed unit. It provides mechanical means of rotating the work at multiple speeds.

2. Which of the following is supported by the headstock?
a) spindle
b) spindle bearing
c) speed change mechanism
d) all of the mentioned
Answer: d
Clarification: These all are supported by the headstock.

3. The spindle is solid.
a) true
b) false
Answer: b
Clarification: This is false. It is not solid. The spindle is hollow in headstock and it is supported by the headstock.

4. Spindle holds dead centers.
a) true
b) false
Answer: b
Clarification: This is false. Spindle holds live centers.

5. Which of the following method is used to vary the speed of a lathe spindle?
a) gear out
b) gear in
c) both gear out and gear in
d) none of the mentioned
Answer: c
Clarification: These both methods are used to vary the speed of the lathe. Apart from these two, variable speed motor is also used to vary the speed of a lathe spindle.

6. Which type of end does tapered bar has?
a) pointed
b) projected
c) pointed or projected
d) none of the mentioned
Answer: c
Clarification: Taper bar may has pointed or projected end depending upon the task. Tapered bar is a bar which has different diameters at both ends.

7. Headstock usually stands on the left side of the lathe.
a) true
b) false
Answer: a
Clarification: Headstock usually stands on the left side of the lathe, while tailstock stands right side of the lathe.

8. Which of the following lathe part serves as a housing for the
back gear, driving pulley etc?
a) tailstock
b) headstock
c) bed
d) none of the mentioned
Answer: b
Clarification: Headstock performs this job. This headstock should be robust as so many cutting forces are involved in it.

9. Spindle is fitted with_____
a) chucks
b) faceplates
c) chucks or faceplates
d) none of the mentioned
Answer: c
Clarification: Spindle is fitted with chucks ( 3 jaw, 4 jaw etc. ) and faceplates. A face plate consists of a circular disc bored out and a chuck is device of lathe attached to the spindle by means of bolts with back late screwed on to the spindle nose.

10. The spindle was directly driven by_____ in later machine.
a) flat belt pulley
b) gear box
c) flat belt pulley and gear box both
d) none of the mentioned
Answer: b
Clarification: Spindle was driven by gear box ( driven by electric motor) in later machine. It is a disc or plate type structure connected to the shaft.

11. The spindle was directly driven by_____ in older machine.
a) flat belt pulley
b) gear box
c) flat belt pulley and gear box both
d) none of the mentioned
Answer: a
Clarification: The spindle was directly driven by flat belt pulley in older machine. Flat pulley generally made up of cast iron, steel, wood, plastic and paper and used with a belt drive is known as flat belt drive.

Machine Tools and Machining Interview Questions and Answers on “Lathe : Tool Material’s Types”

1. Which of the following tool material is not suitable for small diameters?
a) carbon steel
b) carbides
c) carbon and carbides both
d) none of the mentioned
Answer: b
Clarification: Carbides are not suitable for small diameters as these carbides has higher speeds and generally used in rapid stock removal.

2. Which of the following cutting material cannot be forged to shape easily?
a) carbides
b) ceramic
c) stellites
d) none of the mentioned
Answer: c
Clarification: Stellites cannot be forged to shape easily because they are very brittle in nature.

3. Which of the following is not the disadvantage of diamonds?
a) incompressible
b) readily conducts heat
c) rigid machine are required
d) all of the mentioned
Answer: c
Clarification: For ceramics, we need rigid machines. The other two mentioned disadvantages are true for diamond.

4. High speed steel has an excessive wear on______
a) castings
b) hard materials
c) casting and hard materials both
d) none of the mentioned
Answer: c
Clarification: It has excessive wear on casting and hard materials and that’s why can only perform slow and medium cutting speeds.

5. Which of the following has poor shock resistant?
a) carbides
b) diamonds
c) ceramics
d) none of the mentioned
Answer: c
Clarification: Ceramic has poor shock resistant. Apart from this, it has high wear resistance and again has very high stock removal rate.

6. In which tool material, rigid machines are required?
a) ceramics
b) carbon steel
c) diamonds
d) all of the mentioned
Answer: a
Clarification: Ceramics are used for this purpose. They are not suitable for intermittent cut and even for small diameters.

7. Machine tools must be tough enough to withstand_____
a) shock
b) vibration
c) both shock and vibration
d) none of the mentioned
Answer: c
Clarification: Machine tools must be tough enough to withstand these both in order to provide stability against downward pressure and to perform the job more accurately.

8. Carbides are used in_____
a) rapid stock removal
b) higher speeds
c) rapid stock removal and higher speed both
d) none of the mentioned
Answer: c
Clarification: Carbides are used for these both reasons. But they are not used for comparatively small jobs.

9. “Light finishing cuts in expensive forming tools”- this quality is applicable to_____
a) carbides
b) ceramics
c) stellites
d) none of the mentioned
Answer: d
Clarification: The answer should be none of mentioned. This is the quality of carbon steel.

10. Which of the following is easy to grind and generally used for intermittent cut?
a) carbides
b) diamond
c) high speed steel
d) none of the mentioned
Answer: c
Clarification: High speed steel has some advanced quality and so it is very accurate even on small diameters. So it is easy to grind high speed steel. Again, this high speed steel is generally used for intermittent cut.

Machine Tools and Machining for Interviews,

Machine Tools Multiple Choice Questions on “Turret Type Drilling Machine”.

1. Which of the following has higher production rate?
a) table top drill
b) gang drill
c) column drill
d) turret drill
Answer: d
Clarification: Turret drill has higher production rate compare to others. This turret word is derived from Italian word torretta which means a tower.

2. Turret drill generally has ______ axis.
a) horizontal
b) vertical
c) can’t say anything
d) none of the mentioned
Answer: b
Clarification: Turret drill generally has vertical axis. It has it axis along with y axis.

3. In turret drill, drills are mounted in holes.
a) true
b) false
Answer: a
Clarification: It can be easily seen from the construction of this machine. The drills are mounted in holes while the table is used for the fixing of jobs.

4. In turret drill, which of the following is mounted in holes?
a) boring tool
b) ream cutter
c) countersinking tool
d) all of the mentioned
Answer: d
Clarification: All can be mounted in holes. Turret drill is a versatile tool. It can enlarge the drill and perform number of operations. For that purpose, all mentioned types of tools can be mounted in holes.

5. A job is mounted______ in turret drill.
a) on table
b) in holes
c) can’t say anything
d) none of the mentioned
Answer: a
Clarification: A job is mounted on table in turret drill. At the same time, tools are mounted in holes.

6. In turret drill, table can move______
a) in x direction
b) in y direction
c) either in x direction or in y direction
d) none of the mentioned
Answer: c
Clarification: The table can move either in x direction or in y direction in order to accommodate with work.

7. The entire turret can move horizontally inward and outward along with drill.
a) true
b) false
Answer: b
Clarification: This is false. The entire turret can move vertically up and down along with drill.

8. Which type of operation is possible in turret drill?
a) secondary enlargement
b) thrust enlargement
c) both secondary enlargement and thrust enlargement
d) none of the mentioned
Answer: c
Clarification: Both operations are possible in turret drill. Thrust is a reaction force explained by newton in its second and third law.

9. In turret drill, table moment can be_______
a) mechanical
b) hydraulic
c) electrohydraulic
d) all of the mentioned
Answer: d
Clarification: All type of moment can be possible in turret drill. This make this drill more efficient to perform the desired job.

10. Boring and reaming operations are also possible in turret drill.
a) true
b) false
Answer: a
Clarification: Though drills are developed especially for making holes but today these drill machines become a versatile tool which perform various types of operations. These all operations are possible in this machine.

Machine Tools Multiple Choice Questions on “Drilling Operation-2”.

1. A hole is being drilled with 1.5mm drill at a feed of 0.3 mm/revolution and rpm is 70. Calculate the metal removal rate in mm³/minute.
a) 18.5
b) 37
c) 74
d) 148
Answer: b
Clarification: Metal removal rate means the rate at which the metal is removed during the operation. From the formula, m= ( 3.14*d*d*f*n) / 4, we can easily calculate metal removal rate.

2. If drill is 2 mm, feed is 0.2 mm/revolution and metal removal rate is 50 mm^/minute. Then find out the value of rpm.
a) 318.4
b) 159.2
c) 79.6
d) 39.8
Answer: c
Clarification: From the formula, m= ( 3.14*d*d*f*n) / 4. Put all the given values with their respective units in the above equation and you will get the value of n as 79.6 .

3. If drill is 3.15 mm, metal removal rate is 55 mm³/minute and rpm is 170.Then find the value of feed in mm/revolution.
a) 0.02
b) 0.2
c) 0.04
d) 0.4
Answer: c
Clarification: During each revolution of spindle drill moves into the work. That distance is known as the feed.From the formula, m= ( 3.14*d*d*f*n) / 4.

4. If metal removal rate is 100 mm³/minute, rpm is 165 and feed is 0.01 mm/revolution. Then find the value of drill in mm.
a) 8.78
b) 4.41
c) 19.3
d) 77.8
Answer: a
Clarification: From the formula, m= ( 3.14*d*d*f*n) / 4. By substituting all the given values in the above equation, we can easily get the value of drill.

5. If diameter of the drill is 20 mm. Then find the value of depth of cut in mm.
a) 20
b) 10
c) 40
d) none of the mentioned
Answer: b
Clarification: Depth of cut=diameter/2. Depth of cut is equal to half the diameter of the drill used.

6. The diameter of the drill is 20 mm and rpm of drill is 10. Find the value of cutting speed in meter/minute.
a) 0.628
b) 628
c) 0.2
d) 200
Answer: a
Clarification: From the formula, cs = (3.14*d*n) /1000. Cutting speed in a drilling operation is taken as the peripheral speed of the drill.

7. Feed per minute (f1) is 10 and feed per revolution (f2) is 5. Then find the value of rpm.
a) 2
b) 4
c) 1
d) 0.5
Answer: a
Clarification: Rpm = f1/f2. Here, f1=10 and f2=5. We can easily get the value of rpm as 2.

8. If the depth of cut (d1) is 10mm, then find the value of the diameter of the drill (d2).
a) 5
b) 10
c) 20
d) none of the mentioned
Answer: c
Clarification: From the formula, d1= d2/2. Here d1=10. So, d2 sholud be 5.

9. If l=10mm, n=2 rpm and s=5 mm. Then find the value of t. t=machining time in minute, l=length of travel of the drill in mm, n= rpm of the drill and s=feed per revolution of the drill in mm.
a) 0.5
b) 1
c) 2
d) none of the mentioned
Answer: b
Clarification: From the formula, t= l / (n*s). By putting all the given values in the above equation, we can easily get the value of machining time as 1 minute.

10. If l=10mm, n=2 rpm and t=0.5 minute. Then find the value of s. t=machining time in minute, l=length of travel of the drill in mm, n= rpm of the drill and s=feed per revolution of the drill in mm.
a) 5
b) 10
c) 20
d) none of the mentioned
Answer: b
Clarification: From the formula, t= l / (n*s), we can calculate the feed per revolution. Feed per revolution may be defined as the axial distance moved by the drill into the work per revolution.

11. If l=20 mm, t=2 minute and s=5 mm. Then find the value of t. t=machining time in minute, l=length of travel of the drill in mm, n= rpm of the drill and s=feed per revolution of the drill in mm.
a) 0.5
b) 1
c) 2
d) none of the mentioned
Answer: c
Clarification: From the formula, t= l / (n*s). Substitute all the given values in the above equation and you can get the value of t as 2.

12. If d=1, n=1 and f=4. Then find the value of m. d= diameter of drill in mm, n=rpm, f=feed per revolution in mm and m=metal removal rate in mm³/minute.
a) 0.08
b) 1
c) 0.3184
d) none of the mentioned
Answer: c
Clarification: From the formula, m= (3.14*d*d*n*f) / 4. Here d,n and f are given. Substitute these values in above equation, you will easily get value of m as 0.3184 .

13. If d=2, n=4 and f=1. Then find the value of m. d= diameter of drill in mm, n=rpm, f=feed per revolution in mm and m=metal removal rate in mm³/minute.
a) 0.798
b) 1
c) 0.6369
d) none of the mentioned
Answer: a
Clarification: From the formula, m= (3.14*d*d*n*f) / 4. Substitute all tyhe given values in the above equation and you will easily get the value.

14. If cs=1 and n=40, then find the value of d. d=diameter of drill in mm, n=rpm and cs=cutting speed in mm/minute.
a) 7.96
b) 3.98
c) 15.92
d) none of the mentioned
Answer: a
Clarification: From the formula, cs = (3.14*d*n) /1000. Substitute all tyhe given values in the above equation and you will easily get the value of d.