HOA1&2 - Module 3 - PREHISTORCI ARCHITECTURE OF KERALA.pptx
Misalignment Vibration
1. MISALIGNMENT VIBRATION
ADHITYA KURNIA D. 15/385198/TK/43860
AKBAR TETUKO BAGASKORO 15/385203/TK/43865
BENAWA MUHAMMAD ADIB 15/385210/TK/43872
M. DJABBAR YULIANTO 15/381351/TK/43419
3. MISALIGNMENT VIBRATION
Misalignment is condition which caused by:
• improper machine assembly
• thermal distortion, and
• asymmetry in the applied load.
Misalignment is a common cause of machinery malfunction in
coupling and shaft assembly.
4. MISALIGNMENT VIBRATION
Unlike imbalance, misalignment does not produce forces that are
similar in the radius of the machine. Vibration in one radial direction
may be very different in amplitude when compared to vibration in
another radial direction. This is one instance where amplitude
readings are not only helpful in detecting a problem but also helpful
in diagnosing a problem.
Misalignment is can decrease machine component life dramatically
7. PARALLEL MISALIGNMENT
If the misaligned shaft centerlines are parallel but not coincident, then
the misalignment is said to be parallel (or offset) misalignment.
8. ANGULAR MISALIGNMENT
If the misaligned shaft centerlines are neither parallel nor coincident,
then the misalignment is said to be angular misalignment.
This phenomenon create an angle relative to the driven shaft.
10. CHARACTERISTIC OF MISALIGNMENT VIBRATION
• Misalignment can be characterized by indicating the phase.
• Viewing the spectrum of vibration is also way to characterize the
misalignment vibration.
11. PHASE INDICATION
ANGULAR
Angular misalignment is indicated
by an approximate phase
difference of 180 degrees across
the coupling when measured in
the axial direction. Be aware of
mistakes made in measuring axial
phase by not allowing for
transducer orientation.
PARALLEL
Offset misalignment produces
approximately a 180 degree phase
difference when comparing a radial
phase on one machine to the same
radial direction on the other
machine across the coupling. Phase
differences may be anywhere from
150 to 210 degrees. The more severe
the misalignment, the closer the
phase differences will be to 180
degrees.
13. SPECTRUM OF MISALIGNMENT VIBRATION
From previous image we saw a high 1X peak in the axial direction due
to angular (gap) misalignment, and high peaks at 1X, 2X, 3X, and even
4X and 5X in the radial direction due to the parallel (offset)
misalignment.
Peaks would likely higher in vertical at one end of the component (e.g.
motor) but higher in horizontal at the other end of the same
component.
14. HOW TO DETERMINE MISALIGNMENT
• Mechanial Checks for misalignment
• Observation
• Phase analysis
• Discussion with mechanics and operators
15. CONCLUSIONS
The spectral signature of a misaligned machine can vary greatly,
depending on the type and degree of misalignment, the type of
coupling, and other factors.
No single method of reliability testing can determine misalignment.
The best way to determine a misaligned coupling is to measure for
misalignment.
Vibration analysis, along with other reliability technologies, can
improve determining misalignment on a machine that is running
16. REFERENCES
Nakhaeinejad, Mohsen and Suri Ganeriwala. 2009. OBSERVATIONS ON
DYNAMIC RESPONSES OF MISALIGNMENTS. Tech Note, SpectraQuest Inc
Hariharan, V. and PSS. Srinivasan. 2009. Vibration analysis of misaligned
shaft and ball-bearing system. Indian Journal of Science and Technology
Mobius Institute. 2017. Analysis Definitions: Misalignment. Retrieved from
http://www.mobiusinstitute.com/site2/item.asp?LinkID=10002&iVibe=1&sTit
le=Analysis%20Definitions