JNTU Kakinada B-Tech 3-1 RT31032 I METAL CUTTING and MACHINE TOOLS R13 April 2018 Question Paper

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Code No: RT31032
III B. Tech I Semester Supplementary Examinations, May – 2018
METAL CUTTING & MACHINE TOOLS (Mechanical Engineering)Time: 3 hours Max. Marks: 70
Note: 1. Question Paper consists of two parts (Part-A and Part-B) 2. Answering the question in Part-A is compulsory
3. Answer any THREE Questions from Part-B
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PART ?A
1 a) What is rake angle? What is the effect of nose radius in tools? [3M]
b) What are the advantages of automatic lathes? [3M]
c) State the difference between a vertical shaper and a slotter? [4M]
d) How do you specify the grinding wheel? and explain it [4M]
e) Mention four important factors that influence the selection of grinding wheel? [4M]
f) Mention the main differences between CNC and NC? [4M]
PART -B
2 a) Explain the various tool materials. [8M]
b) In an orthogonal cutting test with a tool of rake angle 10?, the following
observations were made:
Chip thickness ratio : 0.3
Horizontal component of the cutting force = 1290 N
Vertical component of the cutting force = 1650 N
From Merchant’s theory, calculate the various components of the cutting forces and
the coefficient of friction at then chip tool interface.
[8M]
3 a) Explain any four commonly used attachments on lathe. [8M]
b) Explain the tooling layout for the production of a Hexagonal bolt in a capstan lathe. [8M]
4 a) Describe wit h a schematic sketch the operation of hydraulic shaper. [8M]
b) Describe with block diagram jig boring machine. [8M]
5 a) Describe the construction of dividing head giving the applications for which it can
be used
[8M]
b) What are the differences between compound indexing and differential indexing?
Explain the relative merits.
[8M]
6 a) Explain any one finishing operation with neat sketch. [8M]
b) Discuss various types of abrasive materials used in grinding wheel. [8M]
7 a) State a few typical applications where the use of numerical control would be
justified.
[8M]
b) What are the common types of drilling jigs? How does a template jig differ from a
plate jig?
[8M]
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R13
SET – 1