Ch. 1 Theory of Metal Cutting

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Nicholas Burns
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1 Ch. 1 Theory of Metal Cutting May 1 Nov Explain types of chips that occur in metal cutting. Why a built up edge on a tool is undesirable and also explain reason behind various chip formation What is tool life? Enumerate the factors affecting tool life. Briefly explain the effect of each factor Differentiate between orthogonal and oblique cutting. Draw merchant's force circle diagram for orthogonal cutting process. Give two examples of oblique cutting. 4 The following relates to orthogonal turning o f a mild steel rod of 50 mm diameter. 4. Feed 0.8 mm; chip thickness 1.2 mm; work rotational speed 0 rpm. Calculate chip thickness ratio (r), chip reduction ratio (K ) and total length of chip removed per minute. 5. What are the methods by which cutting fluids are applied in a machining operation? Explain EP method. 6. Explain with a neat sketch the Mechanical type of lathe tool dynamometer.. List the desired properties required for good cutting tool material and explain any two cutting tool materials. 8. Sketch a single point cutting tool and show on it the various tool elements and tool angles. In an orthogonal cutting operation, the following data have been observed: Uncut chip thickness = 0.12mm Width of cut = 6.35 mm Cutting speed = 2 m/s Cutting force 9. = 56 N Thrust force = 22 N Chip thickness = mm Rake angle = 100 Calculate shear angle, shear stress along the shear plane, chip velocity and the power for the cutting operation

2 10. The useful tool life of a HSS tool machining mild steel at 18 m/min is 3 hours. Calculate the tool life when the tool operates at 24 m/min. Take n = What is Cutting fluid? Explain in brief Purpose of cutting fluids and Properties of Cutting fluids. The following observations were made during orthogonal turning of a mild steel tubing of 50 mm diameter on a lathe. (1) Cutting speed = 30 m/min (2) Tool rake angle 12 = 15º (3) Feed rate = 0.15 mm/rev (4) Tangential cutting force = 2500N (5) Feed force = 1000N (6) Length of continuous chip in one revolution = 100 mm Determine: (i) Coefficient of friction (ii) Shear plane angle (iii) Velocity of chip tool face (iv) Chip thickness 13. Prove that: tan ø = r cos α / (1 r sin α)

3 Ch. 2 Thermal Aspects in Machining May 1 Nov What are the methods by which cutting fluids are applied in a machining operation? Explain EP method. 2. Name several techniques for determining tool chip contact temperature. Describe the Tool/work thermocouple method of measuring temperatures 3. Explain the essential characteristics and function of cutting fluid. 4. Briefly explain about regions of heat generation and also explain about various factors affecting cutting temperature. 5. What is Cutting fluid? Explain in brief Purpose of cutting fluids and Properties of Cutting fluids. What are the methods by which cutting fluids are applied in a machining operation? 6. Explain EP method.

4 Ch. 3 Gear and Thread Manufacturing May 1 Nov List the various types thread manufacturing methods. And explain thread grinding. 2. List the various gear finishing processes and explain any three processes List the various thread manufacturing processes. Explain about thread rolling process. 4. Describe gear hobbing process in detail. 5. Name the two common profiles used for gear teeth Enlist the common methods for gear cutting. 1. Draw sketches of Acme thread and Square thread Differentiate clearly between gear forming and gear generating methods What are the different methods of gear manufacturing? List the methods and explain any one. 13. Explain with neat sketch manufacturing of gear by Gear shaping using pinion type cutters. What are the advantages of this method? 14. Discuss Chasing with neat sketch. 4

5 Ch. 4 Jigs and Fixtures May 1 Nov Explain the degree of freedom of a work piece located in a space with a neat sketch. Analyze the Location of a Cylinder on a Vee Block. 2. Explain location principle with neat sketch. 3. Distinguish between jigs and fixtures. List the design steps for jigs and fixtures. 4. Explain about channel jig and box jig with neat sketch. 5. What is Power clamping? State merits of power clamping over mechanical clamping Explain any one fixture with neat sketch. 4. Draw and discuss Hinged clamping device List the various types of locating devices used for both Jigs and Fixture 3

6 Ch. 5 Press Tool May 1 Nov How the Presses are classified? Sketch and describe any one of it. A round disk of 150-mm diameter is to be blanked from a strip of 3.2mm, half-hard 2. cold rolled steel whose shear strength 310 MPa. Determine (a) the appropriate punch and die diameters, and (b) blanking force. Take clearance allowance for half-hard cold-rolled steel is Explain the various methods of reducing cutting force requirement in press work Explain blanking and lancing operation and Piercing operation. 5. Classify the die associated with press work and explain about compound die and progressive die and Combination Die. 6. Draw neat schematic diagram of a sectioned view of a blanking die and punch assembly and label on it. 4. Write short note on material utilization factor for a sheet metal on a press tool using press tool die Explain the function of (i) Die Block (ii) Punch. 3

7 Ch. 6 Non-Conventional Machining May 1 Nov Write the difference between AJM and AWJM processes from the view point of working principle, application & limitations. 2. Write short note on any two i) LBM ii) USM iii) ECM 4 3. What do you mean by MMR in unconventional machining? How this MMR is affected by various parameters in AJM? 4. Explain basic principle of EDM with neat sketch. And also discuss desired 4 characteristics required for EDM tool. 5. Classify the unconventional machining process and explain about electron 3 beam machining process with neat sketch.. Indicate the sources of energy in ECM and USM Which Abrasives are used in AJM? Describe the operation of electro chemical grinding (ECG) with the help of a neat sketch? What are the differences between ECG and conventional grinding? 12 Explain Advantages, Limitations of Ultrasonic machining briefly What is Laser? Explain briefly the working principle of Laser beam Machining. State its advantages 15. Draw LBM sketch with lables Write important functions of dielectric fluid. 3

8 1. Explain with suitable diagram working of electro discharge machine. State its advantage, disadvantage and application. 18. Draw the neat sketch of ECG method. 3

Manufacturing Science-II (EME-503)

Manufacturing Science-II (EME-503) Time: 1 Hour B.Tech. [SEM V (ME-5 All Groups)] QUIZ TEST-1 Manufacturing Science-II ` Max. Marks: 30 Note: Attempt all the questions Q1) How metal is removed in metal cutting? Explain by giving any simple