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.