This presentation is equipped with the basic concepts of Condition Monitoring. The methods and analysis, circumscribed by Condition Monitoring, are summarized with an addition of application in this presentation.

1. CONDITION MONITORING

2. Major Contents
• Introduction of Condition Monitoring
• Vibration Analysis a Key Component of CM
• Application
• Conclusion

4. Condition Monitoring
• Condition monitoring is the process of
monitoring a parameter of condition in
machinery in order to identify a significant
change which is indicative of a developing
fault.
• It is a major component of predictive
maintenance.

6. Use of Condition Monitoring
• Condition monitoring techniques are normally
used on rotating equipment and other
machinery
• Pumps, electric motors, internal combustion
engines, presses.

7. Techniques of Condition Monitoring

8. Oil Analysis
Oil analysis is the
laboratory analysis of a
lubricant's properties,
suspended
contaminants and wear
debris.
Oil Analysis is
performed during
routine predictive
maintenance to provide
meaningful and accurate
information on lubricant
and machine condition.

9. Thermal
Analysis
It is a branch of
materials science
where the
properties of
materials are
studied as they
change with
temperature.

10. Ultrasonic
Analysis
 Ultrasonic testing is a
versatile technique that
can be applied to a wide
variety of material
analysis applications.
 The motion of wave
will be affected by the
medium through which
it travels.

11. Vibration Analysis
 Vibration Analysis applied in an industrial or
maintenance environment aims to reduce
maintenance costs and equipment downtime
by detecting equipment faults.
 Vibration Analysis is a key component of a
Condition Monitoring program.

12. Vibration Analysis a key component of Condition
Monitoring

13. What is vibration?
 Vibration is a mechanical phenomenon
whereby oscillations occur about
an equilibrium point.
 The oscillations may be periodic, such as “the
motion of a pendulum” or random such as
“the movement of a tire on a gravel road”.

17. What we Measure for
Vibration Analysis?
1. Amplitude
2. Frequency
3. Phase

18. • Amplitude: How
Much Movement
Occurs or severity
of the vibration.
• Units: mm, m, in
• Frequency: How
Often The
Movement Occurs.
How many "cycles"
in a period of time:
a second
• Units: Cycle per
second (Hz)
• Phase: The
Vibration lag
between vibrating
body and the
attached body.
• Units: Degree,
Radian

19. Vibration analysis
Most commonly Vibration Analysis is used to
detect faults in rotating equipment (Fans,
Motors, Pumps, and Gearboxes etc.) such as
 Unbalance
 Misalignment
 Bearing faults
 Resonance conditions

20. Parts of Vibration Analysis system
A vibration analysis system usually consists of
four basic parts:
1. Signal pickups (Sensors)
2. A signal analyzer
3. Analysis software
4. A computer for data analysis and storage.

21. Vibration Analysis System

22. Vibration Analysis System
 Vibration Analysis can use the units of
Displacement, Velocity and Acceleration
displayed as a Time Waveform (TWF), but
most commonly the spectrum is used, derived
from a Fast Fourier Transform of the TWF.
 The vibration spectrum provides important
frequency information that can pinpoint the
faulty component.

23. Vibration Analysis System
Fast Fourier Transform (FFT)
 The Fast Fourier Transform (FFT) takes the
complex waveform and breaks it down into the
component sine waves.
 The amplitudes for each sine wave is then
plotted at the frequency of the sine wave,
creating the Spectrum.

25. So What can Vibration Analysis
Detect?
 Detect and Track progressing stages of
Bearing Failure
 Identify Imbalance and Misalignment
 Vibration Analysis is used to correct
Imbalance
 Identify/correct Resonance
 Identify Mechanical Wear in couplings,
bearings, support structures, etc.

26. Application
Condition Monitoring of Gas Turbine

27. Introduction to Gas turbine
A turbine driven by expanding hot gases produced by burning
fuel, as in a jet engine.
Types:
1) Aeroderivative gas turbines 2) Industrial gas turbines

28. Causes of Vibration in Gas turbine
The following scenarios might cause high
vibration to a rotating equipment:
• Misalignment
• Resonance
• Aerodynamic forces
• Tooth wear, couplings
• Undisturbed bearing lubrication
• Unbalance

29. Failure in Gas Turbine due to Vibration

30. Considerations for Condition
Monitoring
 Vibration analysis
 Combustion instability monitoring
 Flame detection
 Exhaust gas temperature diagnostics
 Over speed detection

31. Vibration Analysis and Diagnostics
 Vibration in Bearings
 Vibration in Shaft
 Vibration in Turbine casing
Method to adopt:
 FFT analysis

32. Vibration Analysis of Gas Turbine
SIEMENS 162MW

33. Elements for condition monitoring
• Usually GT bearings are equipped with radial,
axial and seismic vibration probes.

34. Radial Bearings
 Two proximity
probes should be
mounted in an X-Y
(orthogonal)
configuration at or
near each bearing,
directly observing
the relative motion
between bearing
and shaft.
 Recommended as a
shutdown
parameter.

36. Casing Vibration
 Seismic vibration
transducers should be
mounted on the
machine’s casing
(typically, the radial
bearing housings).

37. Eccentricity
 Gravity sag causing extremely massive rotors to bow from
their own weight after an extended period of time. This can
also affect many of today’s largest gas turbines.
 It is measured using a single radial proximity.

38. Seismic
Transducers
 The seismic
transducers used
in industrial gas
turbines are
specially
engineered to
withstand the
extreme
temperatures and
g-forces
encountered.

39. Expressions to analyse the
behavior

40. Over-speed
Detection
• An electronic
monitoring unit
detects over speed
and an
electrohydraulic
assembly actuates
the trip valve
immediately.

41. Combustion
monitoring
 Combustion
instabilities are a
consequence of this
lean-burn operation,
resulting in pressure
pulsations in the
combustors.
 Dynamic Pressure
Monitor provides this
capability to detect
combustion
instabilities.

42. Exhaust gas
temperature
 In order to monitor the
temperature profile, a
ring of equi-spaced
thermocouples is placed
circumferentially in the
hot gas path at power
turbine exhaust.

43. Flame Sensing
 GE Energy’s Flame
Tracker™ sensor is an
innovative solution for
monitoring the presence
of a flame, as needed
for permissive during
start up, and to ensure
that fuel does not
continue to flow and
build up to potentially
explosive levels.

45. Importance of condition
monitoring for GT
Condition monitoring is extremely important for the gas turbine,
in order to:
 Reduce the frequency/severity of in-service failures
 Increase service life
 Improve operational safety and profitability
 Reduce repair and maintenance costs
 Decrease repair and maintenance times through preplanning and advance
knowledge of requirements

47. Conclusion
• By condition monitoring we mean continuous evaluation of
the health of plant and equipment throughout its serviceable
life.
• Condition monitoring and protection are closely related
functions.
• Condition monitoring can be extended to provide primary
protection, but its real function must always be to attempt to
recognize the development of faults at an early stage.

48. Visual Description

49. References
• https://en.wikipedia.org/wiki/Condition_monitoring
• https://en.wikipedia.org/wiki/Vibration
• http://pubs.sciepub.com/jmdv/2/1/1/
• http://www.slideshare.net/idctechnologies/machinery-
vibration-analysis-and-maintenance-35770202
• http://waset.org/publications/3166/vibration-analysis-of-the-
gas-turbine
• http://1q05_gasturbinevibmonitoring.pdf