JNTU B.Tech II Semester Examinations, METAL FORMING
, Aug/Sep 2008
Time: 3 hours Max Marks: 80
Answer any FIVE Questions
All Questions carry equal marks
1. Write short notes on the following:
(a) Yield locus
(b) Levy-Mises equations(Flow rules). [8+8]
2. (a) What is hot working? Is it possible to have hot working of metals at room
temperature? How? Explain with suitable examples.
(b) Assume that a tapered piece of copper has been stressed in tension beyond its
yield point and then annealed. Explain how the grain size will change along
the taper. [8+8]
3. Define hot working, warm working and cold working.Discuss the relative features
of hot work and cold work for Al, Pt and Molybdenum considering melting point,
brittleness and oxidation behaviour. 
4. Explain the following:
(a) Compound die
(b) Combination die
(c) Progressive die
(d) Transfer die. [4×4]
5. (a) What is Forging? Describe various types of forging dies.
(b) Sketch and describe counter flow forging hammer.
(c) Discuss the advantages and limitations of forging process. [7+4+5]
6. (a) Maximum draft in rolling is decided by coefficient of friction. Explain.
(b) Define Torue and power required for rolling. Describe how they can be esti-
(c) Calculate the rolling load if steel sheet is hot rolled 30 percent from a 40mm-
thick slab using a 900 mm-diameter roll. The slab is 760 mm wide. Assume
? = 0.30. The plane-strain flow stress is 140 Mpa at entrance and 200 Mpa
at the exit from the roll gap due to the increasing velocity. [5+6+5]
7. (a) Describe the common extrusion equipment and basic elements of an extrusion
(b) Briefly explain the deformation and flow of metal during extrusion. [10+6]
8. Discuss the following: [8+8]
(a) Production of tubes and seamless pipes.
(b) Rod and wire drawing processes.