MMEMD105-4 Industrial Tribology M.Tech Model Question Paper : mgu.ac.in

Name of the College : Mahatma Gandhi University
Department : Mechanical Engineering
Subject Code/Name : MMEMD 105-4/Industrial Tribology
Sem : I
Website : mgu.ac.in
Document Type : Model Question Paper

Download Model/Sample Question Paper : https://www.pdfquestion.in/uploads/mgu.ac.in/5091-MMEMD%20105-4%20Tribology.pdf

MGU Industrial Tribology Question Paper

M. TECH. Degree Examination, Model Question Paper – I :
First Semester :
Branch: Mechanical Engineering
Specialisation: Machine Design
MMEMD 105-4 Industrial Tribology (Elective – I)
(Regular – 2013 Admissions)
Time: Three Hours
Maximum: 100 Marks

Related : Mahatma Gandhi University M.Tech Civil Engineering Question Paper Model : www.pdfquestion.in/7532.html

Model Questions

Answer all questions. :
Only approved design-data handbook permitted. :
1. a. What are the prominent theories of friction? (3 marks)
b. State the laws of friction. (3 marks)
c. Briefly explain any 3 theories of wear. (3 marks)
d. Derive Reynolds equation in Cartesian co-ordinates. (16 marks)
Or

2. a. Define viscosity and briefly explain viscosity Index. (5 marks)
b. Explain the mechanism of Pressure development in an oil film. (5 marks)
c. Explain the relevance of Reynolds equation and its components. (5marks)
d. Derive the Hagen- Poiseuille Equation for flow through horizontal and inclined capillary tubes (10 marks)

3. a. The following data is given for a journal bearing :
Radial load of 3.2 kN, Journal speed of 1490 r.p.m, journal diameter of 50 mm, bearing length of 50 mm, radial clearance of 0.05 mm, viscosity of 25 cP.Calculate for the given conditions: a. Coefficient of friction.

b. Power loss owing to friction.
c. Minimal film thickness
d. Flow requirement of oil in litres /minute
e. Temperature rise in the bearing. (18 marks)
b.Briefly describe the mechanism of pressure build-up in a hydrodynamic bearing with relevant figures. (7 marks)
Or

4. a. Explain: i.Sommerfeld number with reference to Reynolds equation.
ii. Bearing Characteristic number
iii. Pressure distribution in Journal bearing, with relevant figure. (12 marks)
b. The following data is given for 360o hydrodynamic journal bearing.
The value of minimum film thickness variable is 0.3. Find the viscosity of oil that needs to be used. (13marks)

5. a. Derive the equation for the load bearing capacity, frictional power loss, energy losses of a hydrostatic step bearing. (15marks)
b. What is the role of restrictors in such bearings? (5 marks)
c. What is air film lubrication? Compare it with oil lubrication. (5marks)
Or
6. a. Explain the working principle of hydrostatic thrust bearing with figures. (12 marks) b. Derive the equation for pressure acting on hydrostatic annular thrust bearing. (13 marks)

7. a. Derive the equations for static load bearing capacity of a rolling element bearing. (10 marks)
b. A ball bearing is operating on work cycle of 3 hours consisting of:
i. a radial load of 3 kN at 1440 r.p.m for one quarter cycle.
ii. a radial load of 5 kN at 720 r.p.m for half cycle.
iii. a radial load of 2.5 kN at 1440 r.p.m for the remaining cycle.
The expected life of the bearing is 10000 hours. Calculate the load carrying capacity of the bearing. (15 marks)
Or

8. a. Explain the possible causes of bearing failure, and remedies. (5marks)
b. Explain briefly the construction of a typical ball bearing with figure and specify the materials used for construction of different parts. (5marks)
c. Explain i. Static Load Carrying capacity ii. Dynamic Load carrying capacity iii. Equivalent load carrying capacity of an anti-friction bearing (10marks)
d. Derive the expression for predicting the L50 life of a bearing. (5 marks)

Basic Mechanical Engg

PART A :
(Answer all questions) (5×3=15)
1) Explain Fourier law of heat conduction.
2) Define COP of a refrigerator.
3) List out the types of belt drives.
4) Compare centrifugal and reciprocating pumps.
5) Explain the types of milling.

PART B :
(Answer all questions) (5×5=25)
6) Define a Quasi-Static process and state its salient characteristics.
7) Compare Petrol and Diesel engines
8) Explain the types of gear trains.
9) Explain the working of a Pelton turbine.
10) List any five properties of moulding sand.

PART C :
(5×12=60)
11) Draw the PV and TS diagrams of an Otto cycle. Derive the expression for the air standard efficiency of the same.
OR
12) 3.5m3 of hydrogen gas at a pressure of 100 KPa and 200C are compressed adiabatically to 4.5 times its 3original pressure. It is then expanded isothermally to its original volume. Determine the final pressure of the gas and the heat transfer. Also determine the quantity of heat that is to be exchanged to reduce the gas to its original pressure and volume. Take the specific heat at constant pressure of hydrogen as 14.3KJ/Kg K .
13) Explain the working of four stroke petrol engine with neat sketches.
OR
14) Explain the working of vapour absorption refrigeration system with the help of a neat sketch.
15) Derive the expression for calculating the length of belt for a cross belt drive.
OR
16) Derive an expression for ratio of belt tensions
17) Explain the different methods of compounding for steam turbines.
OR
18) Explain the general layout of a hydro electric power plant.
19) Explain the principal parts of a lathe with the help of a neat sketch.
OR
20) Explain the different of die casting.