Gear Hobbing and Gear Shaping Processes:

1 List common methods used for gear manufacturing. Why are gear tooth given a specific tooth profile?

2 Sketch a hob with detailed hob nomenclature. Explain the function of each element.

3 Explain with sketches, the gear hobbing process.4 Explain with sketches, the gear shaping process.5 Compare hobbing and shaping as gear manufacturing processes in al possible

contexts.6 What difficulty would be experienced in cutting a herringbone gear?7 Why gear hobbing is more productive than gear shaping process?8 A single threaded hob having diameter of 50 mm is being used to cut a spur

gear having 72 teeth with 3 mm module. The face width of the gear is 32 mm. The axial feed rate is 25 Mm/rev. And the cutting speed selected for the operation is 0.4 m/sec. Find RPM of the gear blank, depth of cut, angle of the hob, cutting time. Assume overrun as 2 mm.

Advanced manufacturing processes: EDM, WEDM & USM

1 What do you mean by non traditional machining? Why they are called so? 2 NTM processes are indispensable for certain circumstances. Justify the

statement.3 How the machining does takes place in Electro discharge machining (EDM)

and ultrasonic machining (USM)? Explain with suitable sketches.4 What is the role of dielectric fluid in EDM, WEDM and slurry in USM?5 Which are types of acoustic units commonly used in USM? Give their relative

advantages and disadvantages.6 Give specific applications of EDM ,WEDM & USM

Chip formation mechanism and temperature measurement

1 List various types of chips formed in machining operations. Note down various factors responsible for each type of chip.

2 What is tool wear? Explain diff. Types of tool wears generally observed in machining process.

3 Explain taylor’s tool life equation . State its importance in metal cutting.4 For a given tool, n=0.5 and C=400. Calculate the percentage increase in tool

life when the cutting speed is reduced by 50%. 5 Why the knowledge of temp. Rise is necessary ? Explain various methods of

measuring the temp. In metal cutting. 6 What is machinability? Explain the importance of machinability in metal cutting

Gas welding processes

1 Distinguish between arc welding and gas welding processes in the context of heat concentration, temp. Generation ,ease of operation and running cost.

2 Describe with sketches the types od flames obtained in an oxy-acetylene gas welding process giving their applications.

3 Explain various problems posed by steels with different carbon percentages in oxygen cutting and how they are overcome.

4 What do you understand by the term ” kerf” in gas welding? Explain its relevance.

High energy rate forming processes

1 State the limitations of conventional forming processes. 2 Explain with suitable sketches the explosive forming process. 3 How electric current can be utilized to form the metal sheets?4 What is water hammer forming? State its applications.

Arc welding processes

1 How do you specify an electric arc welding power source?2 Why DC arc welding is more used than AC arc welding for specialized

applications.3 Which are the parameters that control the weld quality in manual metal arc

welding?4 Explain Tungsten Inert Gas (TIG) & Metal Inert Gas (MIG) welding processes

of arc welding. Give the applications of each.5 Explain the coated electrode designation system.6 What do you understand by overcut and arc blow? How to control it.7 Which are the functions of coating materials in manual metal arc welding and

shielding gases in gas welding? Which are the gases generally being used for gas welding?

8 What is submerged arc welding? What is special about it?

Jigs & Fixtures

1 What is the basic difference between a jig and fixture?2 Explain the 3-2-1 location principle with suitable examples.3 In the context of 3-2-1 location principle analyze (a) a job held between a 3 jaw

chuck and centre (b) self centering vice. 4 How many degree of freedom are restricted by a cylindrical locator? What can

be the problem with such locators? 5 What is the best angle between V-locating surfaces considering the

displacement of axis due to variation in diameter of work piece?6 How does the use of jig and fixture improves the productivity?7 List the general design considerations used while designing jigs & fixtures?