For the reference of vibration analysis.Everything contains about basic only.

1. James Anantharaj.T
Operational Energy Group of India (P) Ltd

2. CONDITIONMONITORING
Condition monitoring is defined as the continuous or
periodic measurement &interpretation of data to indicate
the condition of an equipment to determine the need for
maintenance .

3. MAINTENANCE TYPES
 BREAKDOWN MAINTENANCE
 REGULAR PREVENTIVE MAINTENANCE
 CONDITION BASED MAINTENANCE

4. WHY CONDITION MONITORING ?
Determination of the condition of a machine or device and
its change with time in order to determine its condition at
any given time.

5. PHYSICAL PARAMETERS OF
MEASUREMENT
vibration
Noise
Temperature
Oil Contamination
wear debris etc

6. CONDITION MONITORING
THROUGH
VIBRATION ANALYSIS
What is Vibration?
It is the response of a system
to an internal or external force
which causes the system to
oscillate.

7. AMPLITUDE MEASUREMENT
1. Displacement :
Total distance traveled by the mass.
Unit : Microns
2. Velocity :
Rate of change of displacement. It is the
measure of the speed at which the mass is
vibrating during its oscillation.
Unit : MM/Sec, Inch/sec
3. Acceleration :
It is the rate of change of velocity. The
greater the rate of change of velocity the
greater the forces (P=mf) on the machines.
Unit : MM/Sec2, Inch/sec2

8. VIBRATION
SENSITIVITY DISPLACEMENT
VELOCITY
ACCELERATION
FREQUENCY
CPM
60 600 6000 60000 600 000
10
1
.1
.01
.001
When To Use Disp., Vel. & Acc.?

9. WHAT IS THE ADVANTAGE OF
USING VELOCITY?
 Flat frequency range compared to displacement &
acceleration.
 Almost all machines generate fault frequency between
600CPM to 60KCPM
 Velocity indicates fatigue.
 Velocity is the best indicator of vibration severity.

10. MEASUREMENT DIRECTION -
HORI, VERT, AXIAL

11. CAUSES OF VIBRATION (CONT.,)
1. Unbalance (Static, Couple, Quasi-Static),
2. Misalignment (Angular, Parallel, Combination)
3. Eccentric Rotor, Bent Shaft
4. Mechanical Looseness, Structural Weakness,
Soft Foot
5. Resonance, Beat Vibration
6. Mechanical Rubbing
7. Problems Of Belt Driven Machines

12. CAUSES OF VIBRATION
8. Journal Bearing Defects
9. Antifriction Bearing Defects
(Inner race, Outer race, Cage, Rolling Elements)
10. Hydrodynamic & Aerodynamic Forces
(Blade Or Vane, Flow turbulence, Cavitation)
11. Gear Problems (Tooth wear, Tooth load, Gear eccentricity,
Backlash, Gear misalignment, Cracked Or Broken Tooth)
12. Electrical Problems of AC & DC Motor ( Variable Air Gap,
Rotor Bar Defect, Problems of SCRs)

13. CAUSES OF UNBALANCE
 Uneven distribution of mass of rotor.
 Dirt accumulation on fan rotors.
 Rotor eccentricity
 Roller deflection, especially in paper machines
 Machining errors
 Uneven erosion and corrosion of pump impellers
 Missing balance weights

14. TYPES OF UNBALANCE
 Static Unbalance
 Couple Unbalance
 Overhang Rotor Unbalance

15. Case Study 1:
ID FAN:
Technical Data:
Motor Make: Nayayang, China
Motor Power: 650 KW, 658.8 A, 690 V
Motor Speed: 994 rpm
Fan Make: FLAKT WOODS
Fan Design Capacity: 46.57 Nm3/s
Fan Normal Capacity: 40.50 Nm3/s
Static Inlet Design Pressure: 636 mm WC
Normal Inlet Pressure: 530 mm WC
Type of Coupling: Resilient coupling
Type of foundation: Common metal frame

16. Measurement Location
Vibration velocity in mm/sec RMS
Horizontal
Vertical Axial
Motor Non Drive End 4.1 3.5 3.2
Motor Drive End 6.9 5.6 3.3
Fan Drive End 5.0 4.9 6.5
Fan Non Drive End 3.5 1.4 3.5
At 977 rpm
At 914rpm
Measurement Location
Vibration velocity in mm/sec RMS
Horizontal
Vertical Axial
Motor Non Drive End 5.4 1.7 2.1
Motor Drive End 5.9 4.3 2.5
Fan Drive End 4.3 4.7 8.6
Fan Non Drive End 2.4 0.8 2.6

17. Remarks:
1. Maximum vibration value of 8.6 mm/sec was observed at Fan Drive End
(914 rpm).
2. Observed that overall vibration is less (7.0 mm/sec) in 933 rpm. So 933
to 951 rpm are recommended for operating speed instead of 914 rpm.
3. During dynamic balancing they have added 3.4 kg in impeller .This
weight (3.4 kg) was not exactly placed in the required area. Hence the
dynamic balancing (weight & phase angle) to be rechecked.
4. Lubricate Fan Non Drive End bearing.

18. CAUSES OF MISALIGNMENT
 Thermal expansion - Most machines align cold.
 Machine vibrations.
 Forces transmitted to the machine by pipe or
 support structure.
 Soft foot.
 Direct coupled machined are not properly aligned.
 Poor workmanship.

19. TYPES OF MISALIGNMENT
Angular
Centre lines of two shafts meet at an angle
 Offset
The shaft centre lines are parallel, but
displaced from one another.
 A combination of angular and offset misalignment

20. Case Study 2:
MCWP:
Technical Data:
Pump Make KIRLOSKAR
Pump Capacity 1400 m3/h
Head 27 m
Pump speed 1480 rpm
Type of Coupling Pin-bush coupling
Type of foundation Common metal
frame for motor & pump

21. Measurement Location
Vibration velocity in mm/sec RMS
Horizontal
Vertical Axial
Motor Non Drive End 3.9 1.3 6.2
Motor Drive End 4.6 2.5 6.9
Pump Drive End 1.5 2.5 5.7
Pump Non Drive End 3.3 4.1 6.6
Remarks:
•Maximum vibration value of 6.9 mm/sec was observed at Motor
Drive End.
•Check for coupling misalignment between motor and pump.
•High temperature (up to 98 deg C) measured in motor drive side
hence guard cover at motor cooling fan side to be modified.

22. Spectrum:

23. MECHANICAL LOOSENESS:
 It alone can not create vibration but in the influence of
Unbalance, Misalignment, Bearing problems it amplify the
amplitude.
 It should be corrected first.
Types:
1.Structural frame/base looseness (1X)
2. Cracked structure/bearing pedestal (2X)
3. Rotating looseness - Loose bearing/improper fit
between component parts. (Multiple)

24. Case Study 3:
ACWP:
Technical Data:
Motor Make: CROMPTON GREAVES
Motor Power: 75 KW, 415 V, 119 A
Speed: 1415-rpm
Pump Make: KIRLOSKAR
Head: 45 m
Capacity: 4.5 kg/cm2
Type of foundation: Common metal frame for motor & pump
Handling media: Cooling water

25. Measurement Location
Vibration velocity in mm/sec RMS
Horizontal Vertical Axial
Motor Non Drive End 1.1 2.1 4.3
Motor Drive End 1.5 3.0 4.3
Pump Drive End 8.1 5.7 4.3
Pump Non Drive End 4.3 4.8 3.9
Remarks:
•Maximum vibration value of 8.1 mm/sec was observed at Pump Drive
End.
•Found that looseness between common base frame to foundation in
Motor Drive End. Hence the grouting to be checked.
•Check the impeller for defects or proper sitting/Flow problem.

26. Spectrum:

27. OIL WHIRL
 Cause: Excessive clearance and light radial loading. This
results in the oil film building up and forcing the journal to
migrate around in the bearing at less than one-half RPM.
 It can create metal to metal contact.

28. WHY DOES BEARING FAIL?
1. Improper lubrication
2. Contaminated lubrication
3. Heavier loading from unbalance,Misalignment,
bent shaft etc.
4. Improper handling or installation.
5. Old age (Surface fatigue) .

29. Adaptor Sleeve
Looseness
Type of Bearing
Defects Amplitude Frequency
High in Axial
Usually 2X RPM
Along with 6 to 10X RPM
Axial Play High in Axial Usually 2X RPM
Along with 12 to 15X RPM
Axial Thrust High in Axial Usually 1X RPM, 2X RPM
Along with 15 to 18X RPM
Increased Clearance High in Vertical & Axial Usually 2X RPM
Along with 15 to 18X RPM
Cage Inaccuracies High in Radial DirectionVery High Frequencies
(some times Noise also)
Improper Fit with
Housing
High in Radial
High Frequencies with Increased
Temperature; Phase analysis
indicates slow movement of
reference mark depending on the
severity of improper fit.
Improper Fit with Shaft
High Radial & Axial with
Erratic Readings
Very High Frequency Sometimes
with Knocking Noise.
Characteristics

30. Case Study 4:
PA FAN:
Motor Make: NANYANG EXPLOSION
PROTECTION GROUP
Motor Power: 830 KW, 6600 V, 88 A
Speed: 1490-rpm
Type of coupling: Voith coupling
Fan Flow (Design): 32.8 m³/s
Fan Flow (Opts): 21.1 m³/s
Inlet static pressure: 30 mmwc (-ve)
Type of lubrication in Fan: Oil (Servo system 68)
Handling media: Atmospheric air

31. Measurement
Location
Vibration velocity in
mm/sec RMS
Horizontal Vertical Axial
Motor Non Drive End 0.4 0.2 0.1
Motor Drive End 0.6 0.3 0.1
Voith Drive End 1.0 0.9 1.8
Voith Non Drive End 1.1 0.8 2.0
Fan Drive End 1.0 0.4 1.3
Fan Non Drive End 0.6 0.4 0.5
Remarks:
•Maximum vibration value of 2.0 mm/sec was observed at Voith Non Drive
End.
•Minor bearing defects are started in VDE and FNDE. Hence monitor the
bearing condition.

32. Spectrum:

33. GEAR BOX
RPM1
RPM2
Z1
Z2
GMF (Gear Mesh Frequency)
Z1 .RPM1 = Z2 .RPM2
where Z = no. of teeth and RPM shaft speed

34. GEAR BOX DEFECTS
 Tooth wear
 Gear eccentricity & backlash
 Gear misalignment
 Cracked or broken tooth
 Hunting tooth

35. Case Study 5:
ACC FAN
Technical Data:
Motor Make: ABB
Motor Power: 90KW, 415 V, FLC 153.3 A
Speed: 1475 rpm
Type of coupling: Pin bush coupling
Handling media: Atmospheric air

36. Measurement Location
Vibration velocity in mm/sec
RMS
Horizontal
Vertical Axial
Motor Non Drive End 4.69 2.58 2.72
Motor Drive End 2.60 3.02 1.63
Gearbox Output Non
Drive End
4.04 2.72 8.59
Remarks:
1. Maximum vibration value of 8.59 mm/sec was observed at
GB OP Non Drive End.
2. Check the gearbox for gear mesh frequency and check
gearbox output bearings.

37. Spectrum:

38. HYDRAULIC & AERODYNAMIC
FORCES
FLOW TURBULENCE
• Flow turbulence often occurs in blowers due to variations
in pressure or velocity of air in ducts
• Random low frequency vibration will be generated,
possibly in the 50 - 2000 CPM range

39. Case Study 6:
MOTOR
PUMP
MNDE
PNDE
MDE PDE
CEP
Technical Data:
Motor Make: SIEMENS
Motor Power: 200 KW, FLC 323 A
Speed: 2985-rpm
Type of lubrication : Lithium complex grease
Pump make: SULZER
Type of lubrication : Turbine oil servo -46
Type of foundation: Rigid
Handling media: Condensate water

40. Measurement Location
Vibration velocity in mm/sec
RMS
Horizontal
Vertical Axial
Motor Non Drive End 1.2 0.5 0.8
Motor Drive End 1.4 0.4 0.5
Pump Drive End 7.4 7.1 3.1
Pump Non Drive End 4.0 4.3 3.7
Remarks:
1. Maximum vibration value of 7.4 mm/sec was observed at
Pump Drive End.
2. Check the Pump Drive End bearing for clearance on
opportunity.
•Check the Pump impeller for flow/defect problem.

41. Spectrum:

42. FANS
 Mainly radial vibrations
 FBPF with 1X RPM sidebands.
 Unbalanced horizontal or axial vibrations.
 Inadequate blade clearance (at FBPF or RPM harmonics)
 Uneven velocity distribution across fan inlet gives FBPF
vibrations
Fan Blade Pass Frequency = RPM x no. of fan blades
(FBPF)

43. PUMPS
Vibration signature depends upon operating condition.
pressure, temperature, speed, cavitation….
Centrifugal pumps
 at Vane Pass Frequency = RPM . no. of impeller vanes
 and harmonics.
Gear pumps
 at Gear Mesh Frequency and 1X sidebands
Screw pumps
 at thread rate = RPM . number of threads and its
 harmonics.

44. ELECTRICAL PROBLEM
 Unequal magnetic forces due to rotor not round
 Eccentric armature journals
 Rotor and stator misalignment
 Elliptical stator bore
 Broker bar
 Open and shorted windings

45. VIBRATION TRANSDUCER
 Piezoelectric transducer
(Accelerometer)
 Induction transducer
(velocity probe)
 Proximity probe
(Displacement probe)

46. THERMOGRAPHY
Objectives of Test
 To detect hot or cold area’s
 To determine absolute temperature
 To view Thermal profiles
 To detect temperature loss

47. HEAT TRANSFER MODES
 Conduction
 Convection
 Radiation
Radiation
Conduction
Convection

48. THERMOGRAPHY
Infra Red is part of the Electromagnetic Spectrum
 It travels in straight lines at the speed of light
 The useful part is divided between Short and Long
wavelengths
 Use of the correct wavelength is essential

49. WHY THERMOGRAPHY?
 Non Contact
 Rapid Scanning
 Data can be recorded in differing formats
 Images produced are comprehensive & reliable
 Is there a viable alternative?

50. Eg:
These two glasses visually
appear the same.
Thermal Imaging with an
infrared camera.
“ Paints a different picture.”

51. ELECTRICAL
 Switch Gear
 Fuse boxes
 Cable runs
 Electrical connectors
 Insulation
 Transformers

52. REFRACTORY LININGS
 Torpedo ladles
 Boilers
 Furnaces
 Exhausts
 Ducting
 Kilns

53. ELECTRIC MOTOR BEARING

54. PUMP BEARING

55. BELT DRIVE
Loose or tight belt heats up abnormally

56. PIPE SEDIMENT

57. QUERIES?
THANK YOU!!!