Thapar University 2006 M.E Computer Aided Design Machine Tool Design - Question Paper
Thapar Institute of Engineering & Technology
M.E. (1st Year)
Final Term exam
CD013 (Machine Tool Design)
Thapar Institute of Engineering and Technology, Patiala
Semester Final Examination
CD-013, Machine Tool Design
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ME CAD/CAM and Robotics (Final year) Time: 3 hrs. |
Instructor: Gaurav Bartarya M.Marks:45 |
Attempt all questions. Assume the relevant data, if missing.
(a) Write about mechanical stepless speed regulators in machine tools
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(b) Describe Meander mechanism used in feed box with neat sketch.
(c) Discuss about shapes and profiles of the guideways and their features.
Q. 2 Draw the speed chart for the optimality for the speed box if the number 9 of steps are 18, Nnx1000, Nmm= 20, no. of stages = 3. Motor rpm is 1440. Elaborate each of your decision taken while designing.
(a) Discuss about combination guideways in details with types and sketches. 3
(b) W;hile turning a 750mm long workpiece of 100 mm diameter between 6 centres, cutting force was found to be 150 kgf when the tool was 200 mm from tail stock. Calculate the machine tool system compliance if the stiffness of the saddle head stock and tail stock are 3000, 4000 and 2500 kgf/mm respectively. Also find deflection of workpiece at this point of contact. Also find minimum deflection and its distance from head stock.
(a) Describe about anti friction guidways. What are the types of antifriction 4.5 slide ways? Described with neat sketches. Also describe about protecting devices used in slideways.
(b) Calculate the deflection of the spindle nose due to compliance of spindle 4.5 if it is running under the conditions as given in the figure below. P\ = 400
N, P2 = 300 N , M, = 150Nm, lengths shown in figure 1 are in mm,
stiffness at points A and B are Ka = 2.0 x 104 N/mm , K = 3.5 x 104 N/mm.
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A |
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B |
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(b) If the tool life equation is TV4'54 = 60x 107 where T is in min. and V is in 4.5 m/min. If at the cutting velocity of 30 m/min the vibration amplitude measured is 0.2 mm having a frequency of vibration of 200hz, find out the effect (in percentage) pn tool life due to this vibration.
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Attachment: |
| Earning: Approval pending. |
