53209-mt----precision Engineering

NR

Code No: 53209/MT

M.Tech. – II Semester Regular Examinations, September, 2008 PRECISION ENGINEERING (Advanced Manufacturing Systems) Time: 3hours

Max. Marks:60 Answer any FIVE questions All questions carry equal marks ---

1. a) Explain with a neat sketch how the roundness in turning is affected. b) What are the basic components of displacement error? Briefly explain. c) Discuss how errors are caused due to velocity lags in NC systems. 2. a) Distinguish between: i) Datums and ii) Datum targets, with an example each. b) Explain with sketches the tolerance zones for : i) Positioning a hole and ii) Parrellelism of a surface. c) What would you understand by ‘Equalising Datum’? Explain with an example. 3. a) How do you measure numerically process capability? Explain. b) What do you understand when the process capability index Cpk= 1, Cpk >1 and Cpk < 1? Explain. 4. a) Define the terms: i) Roughness, ii) Waviness and iii) Lay while referring to surface texture. b) Discuss the relationship between attainable tolerance grades and the following machining processes: i) Turning ii) Drilling iii) Reaming iv) Boring v) Grinding and vi) Lapping. Contd…2

Code No: 53209/MT

:2:

5. a) Prepare a process sheet for a typical shaft type component. b) Distinguish between functional and manufacturing datum features. 6. a) Discuss a system of nanometer accuracies in a typical application. b) Explain the mechanism of metal processing with nanotechnology. 7. Describe with a neat sketch a typical in – situ position measurement system. 8. Briefly discuss any three of the following: a) Design features for machining. b) Design of freedom – Datum system. c) Grouped datum system. d) Tolerance worksheets. e) Tolerance analysis – cost aspects.