Production Process 2 - Dec 2015

Mechanical Engineering (Semester 4)

TOTAL MARKS: 80
TOTAL TIME: 3 HOURS (1) Question 1 is compulsory.
(2) Attempt any three from the remaining questions.
(3) Assume data if required.
(4) Figures to the right indicate full marks.

Attempt any four:

1 (a) Explain Gear hobbing process of gear manufacturing.(5 marks) 1 (b) Differentiate orthogonal and oblique cutting.(5 marks) 1 (c) Write short note on Tool holders and inserts(5 marks) 1 (d) Discuss cutting fluids.(5 marks) 1 (e) Prove that V_r=V_c.r(5 marks) 2 (a) Sketch the internal round broach and write briefly on the following elements
i) Rake and relief angles
ii) Depth of cut per tooth
Width of land(10 marks) 2 (b) Prepare the CNC part program for matching of workpiece shown in figure below for ϕ25 size bar stock. (10 marks) 3 (a) Discuss the assumption made in Merchant's theory. Derive the relationship $ 2\phi + \beta = \dfrac {\pi} {2} $(10 marks) 3 (b) State various vertical machining centres. Describe any one in detail.(10 marks) 4 (a) Write note on two dimensional Tool dynamometer.(5 marks) 4 (b) Describe carbides and ceramic as cutting tools.(5 marks) 4 (c) Derive an expression of tool life for minimum cost criteria in metal cutting.(10 marks) 5 (a) A work piece of 38 mm diameter is being turned on a lathe with tool having a rake angle of 33° and period of 0.15 mm/rev. The length of chip over one revolution of workplace is 72 mm. The tangential force is 410 N and feed force is 170 N calculate:
(a) Coefficient of friction on rake force
(b) Thickness of chip
(c) Angle of shear
(d) Velocity of shear(10 marks) 5 (b) Write steps for designing form tool by graphical method.
Design and draw circular form tool having.
Maximum radius = 60mm
Minimum radius = 40mm
Rake angle =10°
Relief angle = 6°.(10 marks)

Write short notes on (any four):

6 (a) Lapping and honing(5 marks) 6 (b) Tool wear(5 marks) 6 (c) Geometry of milling cutter(5 marks) 6 (d) Cutting fluids(5 marks) 6 (e) Co-ordinate measuring machine.(5 marks)