Understanding Synchronous, Non Synchronous and Sub Synchronous Regions
Understanding the differences between synchronous, non-synchronous, and sub-synchronous regions and peaks on a vibration spectrum is crucial for accurate machine analysis and fault diagnostics. Defining the machine’s running speed is essential for proper analysis.
Very Important to the vibration analyst to understand the difference between Synchronous, Non Synchronous and Sub Synchronous regions and peaks on the vibration spectrum and to understand that you could have different groups for different speeds in case you have more than one speed in your machine.
Defining the machine's running speed is very important for the right machine analysis, and fault diagnostics.
For Example :
Synchronous Groups:
1. High 1X could be: Unbalance, bent shaft, eccentricity, soft foot
2. 1X and 2X could be a misalignment, shaft cracks, coupling fault
3. 1X and multiple Harmonics could be rotating looseness or severe misalignment.
Side Bands Group:
1. Rotor bar passing frequency with side bands at 1X could be rotor bar fault.
2. GMF with side bands at 1X could be gear wear.
Non-Synchronous Group:
1. Bearing fault.
2. Transmitted Vibration
Sub Synchronous Group:
1. Pumps Turbulence, recirculation
2. Oil whirling