Download GTU (Gujarat Technological University Ahmedabad) B.Tech/BE (Bachelor of Technology/ Bachelor of Engineering) 2020 Winter 8th Sem 2182503 Design Of Product And Machine Tools Previous Question Paper
Enrolment No.___________
GUJARAT TECHNOLOGICAL UNIVERSITY
BE- SEMESTER?VIII (NEW) EXAMINATION ? WINTER 2020
Subject Code:2182503 Date:19/01/2021
Subject Name:Design of Product and Machine Tools
Time:02:00 PM TO 04:00 PM Total Marks: 56
Instructions:
1. Attempt any FOUR questions out of EIGHT questions.
2. Make suitable assumptions wherever necessary.
3. Figures to the right indicate full marks.
4. Use of PSG Design data book permitted.
MARKS
Q.1 (a) Give functions of machine tool structures and their requirements.
03
(b) Write advantages of geometrical progression.
04
(c) Prove that the loss of economic cutting speed is constant over the whole
07
range of spindle speed in GP series.
Q.2 (a) Discuss causes of failure of rolling contact bearings.
03
(b) Discuss functions and requirements of spindle unit.
04
(c) Design a gear box for milling machine having maximum and minimum
07
speeds are 720 and 18 rpm respectively. Number of spindle speed are
12 and drive is from an electrical motor having 3.5 KW at 1400 rpm.
Draw structural diagram and speed chart.
Q.3 (a) Explain working of face plate variators with sketch.
03
(b) With suitable figure explain operating principle of hydrodynamic
04
journal bearing.
(c) List types of feed boxes and explain any one with neat sketch.
07
Q.4 (a) Give classification of steel wire ropes.
03
(b) Write a note on machine tool chatter.
04
(c) Write a note on Antifriction guide ways.
07
Q.5 (a) Discuss requirements of machine tool structure.
03
(b) Explain step less regulation of speed and feed rates.
04
(c) A full journal bearing of 50 mm diameter and 100 mm long has a
07
bearing pressure of 1.4 N/mm2. The speed of the journal is 900 r.p.m.
and the ratio of journal diameter to the diametral clearance is 1000. The
bearing is lubricated with oil whose absolute viscosity at the operating
temperature of 75?C may be taken as 0.011 kg/m-s. The room
temperature is 35?C. Find: 1. The amount of artificial cooling required
and 2. The mass of the lubricating oil required, if the
difference between the outlet and inlet temperature of the oil is 10?C.
Take specific heat of the oil as 1850 J / kg / ?C.
Q.6 (a) What is product? Give structure of product design.
03
(b) Enlist and explain various factors to be considered for prepare a product
04
design specifications.
(c) A ball bearing is subjected to a radial load of 10 KN and a thrust load
07
of 4 KN. The inner ring rotates at 1000 rpm. The average life is to be
1
5000 hrs. What basic load rating must be used to select a bearing for
this purpose?
Q.7 (a) Draw various design of machine tool spindle end showing standard
03
taper angle.
(b) Define bearing. Give classification of bearings.
04
(c) Design a steel wire rope for a mine hoist for lifting 1500 kg in a single
07
run. The hoist trolley weight 200 kg. the rope has two falls. The
maximum acceleration imparted to the hoist while lifting is 3 m/sec2.
Select 6 x 19 rope having ultimate breaking strength of 1400 N/ mm2
and Er = 9.8 x 104 N/mm2. Considered total no of bends = 6.
Q.8 (a) Explain factors to be considered for selection of material handling
03
equipment.
(b) Explain types of radial ball bearings.
04
(c) Design a crane hook for lifting capacity of 7.5 tonnes. It is made of
07
forged steel and has approximate triangular section. Take permissible
tensile stress 125 N/mm2 for forged steel.
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This post was last modified on 04 March 2021