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.