Definition
Misalignment is a deviation between the centerlines of two connected rotating components (most commonly across a coupling between a motor and a driven machine) that should otherwise share a common axis. It produces a characteristic vibration signature, often with strong axial components, and accelerates wear on bearings, seals, and the coupling itself.
Key facts
- Refers specifically to centerline deviation between connected rotating shafts, most commonly at a coupling.
- Can be angular (shafts at an angle), parallel/offset (shafts parallel but not concentric), or a combination of both.
- Produces a characteristic vibration signature, commonly at 1x and 2x running speed with significant axial vibration components.
- Accelerates wear on bearings, seals, and the coupling, and increases energy consumption if left uncorrected.
What does Misalignment reveal about failures?
Misalignment occurs when the rotational centerlines of two coupled shafts (typically a driver such as a motor and a driven machine such as a pump) deviate from the shared axis they should have, imposing additional cyclic load on the coupling and adjacent bearings with every rotation.
How do teams use Misalignment in failure analysis?
Misalignment is recognized through vibration analysis showing a characteristic signature, often dominant at 1x and 2x running speed with notable axial (along-the-shaft) vibration components, and is confirmed through direct alignment measurement (laser or dial indicator) across the coupling.
FAQ
Frequently asked questions
What does misalignment of connected assemblies mean?
It means a deviation between the centerlines of two connected rotating components, most commonly across a coupling, producing a characteristic vibration signature and accelerating wear on bearings and seals.
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