Name of the College : Mahatma Gandhi University
Department : Mechanical Engineering
Subject Code/Name : MMEMD 106-3/Vibration Control and Condition Monitoring
Sem : I
Website : mgu.ac.in
Document Type : Model Question Paper
Download Model/Sample Question Paper : https://www.pdfquestion.in/uploads/mgu.ac.in/5092-MMEMD%20106-3%20Vibration%20control%20and%20CM.doc
MGU Vibration Control & Condition Monitoring Paper
M. TECH. Degree Examination, Model Question Paper – I :
First Semester :
Branch: Mechanical Engineering
Related : MGU MMEMD105-1 Design of Pressure Vessels & Piping M.Tech Model Question Paper : www.pdfquestion.in/5090.html
Specialization:
MMEMD 106-3 Vibration Control and Condition Monitoring (Elective – II)
(Regular – 2013 Admissions)
Time: Three Hours
Maximum: 100 Marks
Machine Design
1(a) Discuss how damping can be used as a tool for controlling the excessive response of a vibration system. (10 marks)
(b) A washing machine of mass 50 kg operates at 1200 rpm. Find the maximum stiffness of an isolator that provides 75% isolation. Assume that the damping in the isolator is negligible. (15 marks)
Or
2(a) With a neat sketch describe the various components involved in an active vibration control system. (10 marks)
(b) A sensitive electronic system of mass 30 kg, is supported by a spring-damper system on the floor of a building that is subjected to a harmonic motion in the frequency range 10-75 Hz.
If the damping ratio of the suspension is 0.25, determine the stiffness of the suspension if the amplitude of vibration transmitted to the system is to be less than 15 % of the floor vibration over the given frequency range. (15 marks)
3(a) Draw a bathtub curve and explain various Machine maintenance techniques. What are the merits of condition based maintenance techniques over preventive maintenance techniques. (15 Marks)
(b) What are the three types of instrumentation systems used in condition monitoring and explain one by one. (10 Marks)
Or
4(a) What is meant by overall vibration level monitoring? Explain the significance deciding the action required level and lead time in connection with overall level monitoring. (13 marks)
(b) Why power spectral density is considered as the signature of a machine and how it can be used for the condition monitoring? (12 Marks)
5(a) What are the different types of transducers used in ultrasonic examination. Give their merits and demerits. (13 Marks)
(b) Explain how shock Pulse Method (SPM) can be used for the condition monitoring of rolling-element bearing? (12 Marks)
Or
6(a) What is ‘Thermography’? Why is thermography used in visual inspection techniques for condition monitoring. (12 marks)
(b) What is meant by Ferrography? How is Ferrography different from wear debris analysis? Explain the application of ferrography in condition monitoring. (13 Marks)
7(a) What is meant by field balancing? What are the advantages of field balancing over shop balancing? (10 Marks)
(b) An unbalanced flywheel shows an amplitude of 0.165 mm and a phase angle of 15o clockwise from the phase mark.
When a trial weight of magnitude 56 gm is added at an angular position of 45o counterclockwise from the phase mark, the amplitude and phase angle become 0.224 mm and 35o counterclockwise respectively.
Find the magnitude and angular position of the balancing weight required. Assure that the weights are added at the same radius. (15 Marks)
Or
8(a) With a neat sketch represent the following three type of misalignments, (1) offset misalignment, (2) angular misalignment and (3) offset and angular misalignment. How the offset misalignment is differed from the angular misalignment. (10 Marks)
(b) With a neat sketch explain reverse dial indicator method for machine alignment. What are the demerits of this method? (15 marks)
Syllabus
Module 1 :
Vibration Control – Review of Fundamentals of Single Degree Freedom Systems, Multi Degree Freedom Systems and Continuous systems. Reduction of Vibration at the Source – Control of Vibration – by Structural design – Material Selection – Localized additions – Artificial damping
Resilient isolation, Vibration isolation, Vibration absorbers. Active vibration control – review of smart materials – types and characteristics – smart structures.
Module 2 :
Selecting methods of condition monitoring – Machine condition monitoring and diagnosis – Vibration severity criteria – Machine maintenance techniques – Machine condition monitoring techniques – Vibration monitoring techniques – Instrumentation systems – Choice of monitoring parameter.