### Anna University - DESIGN OF MACHINE ELEMENTS - 2007 Question paper

B.E. PRODUCTION ENGINEERING
V Semester

PR 332 - DESIGN OF MACHINE ELEMENTS

Time : 3 Hours Max Marks : 100 marks

Part A (10 x 2 = 20 Marks)

1. What are alloy sheets? State the effect of the following alloying elements in steel.
i) Chromium ii) Manganese iii) Vanadium iv) Sulphur
2. The recommended class of transition fit between the recess and the spigot of a rigid coupling is 60H6-j5. Find the dimensions of the two components.
3. Define endurance limit of a material under fluctuating stresses.
4. Explain the possible ways to reduce the severity of stress concentration by correcting the geometric shape.
5. Sketch a modified Good-man diagram for bending stress due to fluctuating stress and the equation for factor of safely.
6. Distinguish between helical compression and tension springs.
7. What are the advantages of helical gear over spur gear?
8. Give two applications for outer-race fixed ball bearings and inter-race fixed ball bearings.
9. Sketch and explain Geometric progression saw tooth diagram.
10. Mention any four available software for modeling and analysis.

PART B (5 x 16 = 80 marks)

11. A plate pin-type flexible coupling is used to transmit 15kW power at 100 r.p.m. There are six pins and their pitch circle diameter is 200mm. The permissible shear and bending stress in the pin are 35 and 152 N/mm2. The coupling is made of C.I. and the permissible shear stress is 10N/mm2 and tensile stress is 60N/mm2. Design and sketch the coupling.

12.a) A plate subjected to a tensile force of 5kN is shown in Figure 12a. The plate is grey cast iron FG200 and the factor of safety is 2.5. Determine the thickness of the plate.

OR

12.b) A transmission shaft of cold drawn steel 27Mn 2 (ultimate strength = 500N/mm2 and yield strength 300 N/mm2) is subjected to a fluctuating torque which varies from – 100N-m to 400 N-m. The factor of safety is 2 and the expected reliability is 90%. Neglecting the effect of stress concentration determine the diameter of the shaft.

13.a) A pulley is keyed to a shaft midway between two bearings. The shaft is made of cold drawn steel for which the ultimate strength is 600 N/mm2 and the yield strength is 450N/mm2. The bending moment at the pulley varies from –200N.m to 400 N.m and the torque on the shaft varies from – 100 N.m to 250 N.m. Design a suitable shaft for infinite life. Assume the following additional parameter:

Factor of safety = 1.5
a) in bending = 1.0 b) in torsion = 0.6
size factor = 0.85 surface factor = 0.9
Stress correction factor
a) in bending = 1.6 b) in torsion = 1.3

OR

13.b) Design a suitable spring for the exhaust valve of a petrol engine. The spring should be capable of exerting a net force of 360N when the valve is open and 220N when it is closed. The maximum inside diameter of the spring is 25mm. The compression in spring is 8mm.

14.a) Design a spur gear which is required to transmit 10kW power. The speeds of the driving motor and the driven machine are 400 r.p.m. and 200 r.p.m. respectively. The approximate center-distance may be taken as 600mm. The teeth have 20° full-depth involute profile. Assume that the gear is made of cast iron FG200, having allowable strength of 75 N/mm2 and 180BHN core hardness.

OR

14.b) A V-belt drive is required to transmit 16kW power to a compressor. The motor r.p.m. is 1440 and the speed reduction ratio is 3.6. Design the belt drive.

15.a) A hydrodynamic full journal bearing is to carry a load of 25 KN at a speed of 300 r.p.m. The journal diameter is 150 mm and length of bearing is 75mm. SAE 30 oil is used with an average operating temperature of 55°C. If the radial clearance is 0.075 mm. Calculate the power loss, the side leakage and the minimum film thickness.

OR
15.b) Determine the geometric dimensions of a 6-station Geneva wheel for the driving crank radius of 100mm.

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### Anna University - DESIGN OF MACHINE ELEMENTS Model Question paper

MODEL QUESTION PAPER
B.E. Degree Examinations
Mechanical Engineering
SEMESTER : V
ME 331 - DESIGN OF MACHINE ELEMENTS

Time : 3 Hours Maximum Marks : 100

USE OF APPROVED DESIGN DATA BOOK PERMITTED

PART - A 10 x 2 = 20 Marks

1. Sketch the stress-strain diagram for a ductile specimen and indicate its salient features.
2. Indicate the type of fit used in the assembly of bush in the big-end of the connecting rod of an automobile.
3. Define ‘endurance limit’ in design
4. Indicate the type of fit specified by 120 H7 p6 in a drawing.
5. Mention any two desirable properties of the material used in an automobile piston.
6. Sketch and indicate the salient parts of a flange coupling.
7. Mention the stresses induced in a taper key used in a coupling.
8. What is a ‘bearing characteristic number’.
9. Mention the names of any four theories of failure.
10. Define ‘coefficient of fluctuation of speed’ in a flywheel.

PART – B 5 x 16 = 80 Marks

11. i) A load of 5 KN is to be raised by means of a steel wire. Find the minimum diameter required, if the permissible stress in the wire is not to exceed 100 N /mm2 (4 Marks)

ii) A square bar of 20 mm x 20 mm in section is subjected to a bending moment of 1000 Nmm. Calculate the stress induced in the top and bottom fibres of the bar. What will be stress in the above fibres, if the bar is additionally acted upon by a tensile stress of 50 N/mm2 along the axis. (6 Marks)

iii) A circular shaft is to transmit a torque of 500 Nmm at a speed of 1000 rpm. Find out the diameter of the shaft, if the permissible shear stress in the shaft material is 70 N/mm2. (6 Marks)

12.a) A shaft is supported by two bearing arranged 1 m apart, A 600 mm diameter pulley is mounted at a distance of 300 mm to the right of the left hand bearing and this drives a pulley directly below it with the help of a belt having maximum tension of 2.25 kN. Another pulley of 400mm diameter is placed 200 mm to the left of the right hand bearing and is driven with the help of an electric motor and a belt, horizontally to the right. The angle of contact for both the pulley is 1800 and the coefficient of friction is 0.24. Design the diameter of the solid shaft, allowing a working stress of 60 N/mm2 in tension and 40 N/mm2 in shear for the material of the shaft. Assume the torque input & torque output are equal.
OR
12.b) A bar of circular cross section is subjected to alternating tensile forces varying from a minimum of 200 kN to maximum of 500 kN. It is to be manufactured from a material with an ultimate tensile strength of 90 MPa and an endurance limit of 70 MPa. Determine the diameter of the bar using safety factors of 3.5 in ultimate tensile strength and 4 in endurance limit strength and stress concentration factor of 1.65 for fatigued load. Use Goodman relation for the basis of design.

13.a) A circular rod 45 mm diameter and 210 mm long is welded to a steel plate with axis of the rod perpendicular to the plate. The rod is subjected to a load of 10 kN at the free end, the direction of the load being perpendicular to the axis of the rod. The material of the plate & the rod are Mild Steel. Determine the size of the weld to withstand the loading.
OR
13.b) An electric motor weighting 5 kN is to be lifted by eye-bolt, which has been screwed into the body of the motor. Define the eye-bolt, assuming suitable proportions, if the permissible stresses for the bolt material are 60 MPa, 30 Mpa and 80 MPa in tension, shear and crushing respectively.

14.a) Select a deep groove ball bearing for a radial load of 4000 N and an axial load of 5000 N, operating at speed of 1600 rpm for an average life of 5 years at 10 hours per day. Assume uniform and steady load.
OR
14. b) Design a connecting rod for a petrol engine for the following data:

Diameter of the piston = 68 mm
Stroke length = 80 mm
Length of connecting rod = 160 mm
Maximum explosion pressure = 3.5 N/ mm2
Mass of reciprocating parts = 2.5 kg
Speed = 4000 rpm
Compression ratio = 8 :1

15.a) A helical compression spring of the exhaust valve mechanism is initially compressed with a pre-load of 375 N. When the spring is further compression and the valve is fully opened, the torsional shear stress in the spring wire should not exceed 750 N/mm2. Due to Space limitations, the outer diameter of the spring is not exceed 42 mm. The spring is to be designed for minimum weight. Calculate the wire diameter and the mean coil diameter of the spring.

OR
15.b) A semi-elliptic leaf spring consists of two extra full-length leaves and six graduated length leaves, including the master leaf. Each leaf is 7.5 mm thick and 50 mm wide. The center-to-centre distance between the two eyes is 1m. The leaves are pre-stressed in such a way that when the load is maximum, the stresses induced in all the leaves are equal to 350 N / mm2. Determine the maximum force that the spring can withstand.

### Anna University - COMPUTER AIDED MANUFACTURING - 2007 Question Paper

ME 338 – COMPUTER AIDED MANUFACTURING

TIME – 3 Hours MAXIMUM : 100 Marks

PART – A (10 x 2 = 20 Marks)

1. What is the basis for forming groups in group technology?
2. Justify the importance of rapid prototyping technology in the current day manufacturing scenario.
3. Briefly state about the co-ordinate axis nomenclature of a modern CNC milling machine.
4. Distinguish point to point and continuous path CNC control.
5. What is a machining center? How it differs from conventional CNC milling machine?
6. What is a rotary type encoder?
7. What do you understand by ‘modal’ and ‘non-modal’ G codes
8. What is meant by canned cycle? List any 4 types of canned cycle machining.
9. What are the objectives of Product Data Management system?
10. What is the philosophy of Just in Time (JIT)?

PART – B (5 x 16 = 80 Marks)

11. (i) Describe the types of electrical drives used for speed
and feed control in CNC machine tools (8 Marks)

(ii) Explain constructional features of linear slides of CNC
machines (8 Marks)

12. (a). (i) Explain the Optiz coding system generally used in group
technology. (8 Marks)

(ii) Explain the methodology to the followed for developing a
generative type computer aided process planning system (8 Marks)

(OR)

(b). (i) Explain the stages involved in the development and
manufacturing of a new product (8 Marks)
(ii) With a neat sketch, explain the principle of any one type
of currently used Rapid Prototyping technology (8 Marks)

13.(a). (i) With a block diagram, explain the various sub-systems
and functions of a modern CNC controller. (8 Marks)
(ii) Explain the following in CNC machining
1. Linear interpolation
2. Circular interpolation
3. Cubic interpolation (8 Marks)

(OR)

(b) (i) What are the different types of contouring system in a
CNC machine? Explain with neat sketches. (8 Marks)
(ii) Explain various types of input devices used in modern
CNC controller for loading programs. (8 Marks)

14. (a). (i) Explain the code used for the following in CNC part
program with example.
1. Circular interpolation in XY plane
2. Tool length compensation
3. Absolute programming (6 Marks)

(ii) For the component shown in Fig Q 14 (a) ii, prepare the
part program using ISO codes. Clearly indicate axis and
the selection of datum point on the sketch of the part. (10 marks)

(OR)

(b). (i) Describe the function of a post processor in computer
aided of part programming (6 Marks)
(ii) For the shown fig Q 14 (b) ii, write part program
using the APT language. (10 marks)

15. (a). (i) Briefly explain about production planning process in
discrete part manufacturing (8 Marks)
(ii) Explain the following
1. Master production scheduling
2. Resource requirement planning
How are they related? (8 Marks)
(OR)
(b). (i) Write about the approaches to be followed to achieve
the goals of JIT. (8 Marks)
(ii) Explain the various data required for a product
Data Management system (8 Marks)

### Anna University - COMPUTER AIDED MANUFACTURING - MODEL QUESTION PAPER

ANNA UNIVERSITY, CHENNAI 25

MODEL QUESTION PAPER

B.E. MECHANICAL ENGINEERING, VI SEMESTER

ME 338 – COMPUTER AIDED MANUFACTURING

TIME – 3 Hours MAXIMUM : 100 Marks

PART – A (10 x 2 = 20 Marks)

1. What is the basis for forming groups in group technology?
2. Justify the importance of rapid prototyping technology in the current day manufacturing scenario.
3. Briefly state about the co-ordinate axis nomenclature of a modern CNC milling machine.
4. Distinguish point to point and continuous path CNC control.
5. What is a machining center? How it differs from conventional CNC milling machine?
6. What is a rotary type encoder?
7. What do you understand by ‘modal’ and ‘non-modal’ G codes
8. What is meant by canned cycle? List any 4 types of canned cycle machining.
9. What are the objectives of Product Data Management system?
10. What is the philosophy of Just in Time (JIT)?

PART – B (5 x 16 = 80 Marks)

11. (i) Describe the types of electrical drives used for speed
and feed control in CNC machine tools (8 Marks)

(ii) Explain constructional features of linear slides of CNC
machines (8 Marks)

12. (a). (i) Explain the Optiz coding system generally used in group
technology. (8 Marks)

(ii) Explain the methodology to the followed for developing a
generative type computer aided process planning system (8 Marks)

(OR)

(b). (i) Explain the stages involved in the development and
manufacturing of a new product (8 Marks)
(ii) With a neat sketch, explain the principle of any one type
of currently used Rapid Prototyping technology (8 Marks)

13.(a). (i) With a block diagram, explain the various sub-systems
and functions of a modern CNC controller. (8 Marks)
(ii) Explain the following in CNC machining
1. Linear interpolation
2. Circular interpolation
3. Cubic interpolation (8 Marks)

(OR)

(b) (i) What are the different types of contouring system in a
CNC machine? Explain with neat sketches. (8 Marks)
(ii) Explain various types of input devices used in modern
CNC controller for loading programs. (8 Marks)

14. (a). (i) Explain the code used for the following in CNC part
program with example.
1. Circular interpolation in XY plane
2. Tool length compensation
3. Absolute programming (6 Marks)

(ii) For the component shown in Fig Q 14 (a) ii, prepare the
part program using ISO codes. Clearly indicate axis and
the selection of datum point on the sketch of the part. (10 marks)

(OR)

(b). (i) Describe the function of a post processor in computer
aided of part programming (6 Marks)
(ii) For the shown fig Q 14 (b) ii, write part program
using the APT language. (10 marks)

15. (a). (i) Briefly explain about production planning process in
discrete part manufacturing (8 Marks)
(ii) Explain the following
1. Master production scheduling
2. Resource requirement planning
How are they related? (8 Marks)
(OR)
(b). (i) Write about the approaches to be followed to achieve
the goals of JIT. (8 Marks)
(ii) Explain the various data required for a product
Data Management system (8 Marks)