UN CONVENTIONAL MACHINING PROCESSES - · PDF fileUN CONVENTIONAL MACHINING PROCESSES ... 8 Explain in detail about working principle, ... 6 Describe the electron beam machining process

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IV B.Tech I Semester Supplementary Examinations, Feb/Mar - 2015

UN CONVENTIONAL MACHINING PROCESSES (Mechanical Engineering)

Time: 3 hours Max. Marks: 75

Answer any FIVE Questions

All Questions carry equal marks

*****

1 How will you analyze the applicability of different processes to different types of

materials, namely metals, alloys, and non metals? Presentation in the form of a

table is preferred. [15]

2 a) Make a comparison between ultrasonic machining and conventional grinding. [5]

b) What are the actions do the ultrasonic vibrations imparted to the fluid medium

surrounding the tool have? What are the process criteria of USM? What are the

various process parameters that govern the process criteria? [10]

3 a) Draw the schematic layout of abrasive jet machine and explain its operational

characteristics. What are the methods adopted to have an effective control over

the mass flow rate of the abrasive. [10]

b) What are the applications of water jet machining [5]

4 a) How will you carry out the analysis for optimization of metal removal rate in

EDM process? [8]

b) What are the functions of dielectric fluid used in Electric Discharge Machining? [7]

5 a) Discuss in detail about the thermal features of LBM and explain the construction

and working of LBM. [10]

b) Distinguish between the electron beam machine and laser beam machine [5]

6 a) Explain metal removal mechanism in Plasma Arc machining with neat sketch. [8]

b) Can you machine electrically non conductive materials by PAM? Justify your

answer. [7]

7 Explain with neat sketch, working of Electro stream drilling and discuss their

advantages, limitations and applications. [15]

8 Briefly explain the following:

i). Characteristics of Cut and Peel Maskants

ii). Chemistry involved in Electro chemical machining

iii). Limitations of chemical machining

[5]

[5]

[5]

Code No: R41034 Set No. 1 R10

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1 What are the basic limitations of conventional machining process? Justify the

need of unconventional machining process in today’s industries.

[15]

2 Write short notes on the following related to ultrasonic machining (USM):

a) Transducers used in USM machine

b) Functions of slurry and oscillator in USM

c) Grain size Vs. Machining rate

[5]

[5]

[5]

3 a) Write short notes on material removal rate and wear rate of nozzle in WJM. [8]

b) Explain how material is removed in AWJM.

[7]

4 a) In chemical machining, what are the factors by which the selection of etchants

is governed.

[7]

b) In an ECM process for machining iron it is desired to obtain a metal removal

rate of 1cm3/min. Determine the amount of current required for the process.

Assume that Atomic weight of iron = 56 gram, Valency at which dissolution

occurs= 1.3, Density of iron = 7.8 gm/cm3 and faradays constant= 1609 amp-

min.

[4]

c) Write limitations of Electro chemical machining.

[4]

5 Explain in detail about the positioning system, wire drive system, power

supply, and dielectric system of wire cut EDM. Also discuss its process

parameters and their effects.

[15]

6 a) Briefly explain the “population inversion between energy levels” with respect

to the laser beam machining.

[8]

b) Explain process parameters, advantages and limitations of Electron beam

machining.

[7]

7 a) Explain the parameters that are affecting the performance of plasma arc

machining.

[5]

b) What is non transferred and transferred mode of plasma arc and explain their

mechanism of material removal.

[10]

8 Explain in detail about working principle, advantages and applications of

shaped tube electrolytic machining.

[15]


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1 Explain the need for the development of unconventional machining process by

considering any four simple cases of your own interest.

[15]

2 Find out the approximate time required to machine a hole of diameter

equal to 6.0 mm in a tungsten carbide plate (Flow strength of work

material= 6.9 x 109 N/m

2) of thickness equal to one and half times of

hole diameter. The mean abrasive grain size is 0.015mm diameter. The feed

force is equal to 3.5 N. The amplitude of tool oscillations is 25 microns and the

frequency is equal to 25 kHz. The tool material is copper having flow strength=

1.5 x 109N/m

2. The slurry contains one part of abrasives to one part of water.

Take the values of different constant as

K1 = 0.3 , K2 = 1.8x 10-6

( In SI units) and K3= 0.6 and abrasive slurry density

= 3.8 g/cm3. Also calculate the ratio of the volume removed by throwing

mechanism to the volume removed by hammering mechanism.

[15]

3 a) Discuss the effect of following process parameters on MRR in AJM.

i). Stand of distance and MRR

ii). Effect of abrasive grain size and flow on MRR

iii). Effect of Mixing ratio on MRR

[9]

b) State clearly the process capabilities of AJM

[6]

4 a) Explain various types of tool designs in ECM. [10]

b) In what ways the electrochemical grinding differs from ordinary grinding

process.

[5]

5 Explain the following in Electric discharge machining (EDM) with neat sketch:

i). Electrode feed control system

ii). Factors to be considered for EDM machine tool selection

[15]

6 a) What is laser? Explain how it is used to machine the materials. [5]

b) Explain the principle and elements of EBM, also how the work table is

protected from getting damaged by electron beam.

[10]

7 a) Discuss the process parameters that influence on the quality of the cut in PAM. [8]

b) List applications of plasma in manufacturing industries. [7]

8 a) Explain in detail about applications of shaped tube electrolytic machining. [8]

b) Explain working of abrasive flow finishing with neat sketch. [7]


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1 a) Classify unconventional machining processes based on basic mehanism

involved in the process and medium for tranfer of enrgies and type of energy

required to shape materials.

[10]

b) Is uncoventional machining process an alternate or complement to conventional

machining process?Justify.

[5]

2 a) Briefly discuss about the mechanisms involved in material removal using USM. [9]

b) Explain various tool feed mechanisms used in USM.

[6]

3 a) Explain the working principle of Water jet Cutting with neat sketch. [8]

b) Material removal rat in AJM is 0.5 mm3/sec. calculate MRR/impact if the

mass flow rate of abrasive is 3gm/min, density is 3 gm/CC and grit size is

60 microns . Also calculate the indentation radius.

[7]

4 a) Why maskants are required in chemical machining process. Explain [7]

b) Describe the electrochemical honing process with neat sketch

[8]

5 a) What are the different types control circuits used in EDM Process. [10]

b) What are the basic requirements of tool materials in EDM process? Name any

four tool materials.

[5]

6 Describe the electron beam machining process with a simple sketch and write

about its process parameters, advantages, and applications.

[15]

7 a) How MRR could be effect on surface finish and Accuracy in PAM. [8]

b) List the applications plasma in machining.

[7]

8 Write short notes on following:

i). Principle of magnetic abrasive finishing

ii). Applications of abrasive flow finishing

iii). Limitations of Electrostream drilling

[5]

[5]

[5]


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UN CONVENTIONAL MACHINING PROCESSES - · PDF fileUN CONVENTIONAL MACHINING PROCESSES ... 8 Explain in detail about working principle, ... 6 Describe the electron beam machining process