How are shaft vibration and shaft displacement generated?
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How do shaft vibration and shaft displacement occur? Could some expert help me answer this question?
Axial displacement occurs due to the thrust exerted on the shafting, and this thrust results from the forces acting on the rotor; the total thrust of the unit stems from the combined forces acting on the rotor shafting； Shaft vibration results from the combination of various factors such as forces acting on the rotor, oil film vibration, and the rotor’s natural vibration. This post was last edited by Longsky Eagle on 2008-10-4 09:16.]
Unbalanced operation of the equipment can easily cause the shaft to vibrate as well. As for the movement of the shaft, it is generally caused by axial forces. For example, in a pump, an uneven force that exists between the high-pressure and low-pressure sides leads to shaft movement (this issue is resolved using balance discs). Similarly, in a screw compressor, there is also an axial force from the outlet to the inlet side (this is controlled by thrust bearings). Please, poster, make your questions clearer in the future!
The causes of shaft vibration can be attributed to the rotor itself, such as: rotor misalignment； Coupling installation issues ； The bearing clearance is too small ； There are also operational reasons such as fluctuations in lubricating oil pressure ； Compressor surge ； Lubricant temperature too low ； The main cause of shaft displacement is excessive axial thrust. Excessive pressure fluctuations at the compressor inlet and outlet ； Excessive speed fluctuations ； Unit surge and pumping out gas can both cause excessive shaft displacement in the compressor.
Displacement should be the result of changes in the axial force acting on the rotor, while vibration should be the result of a breakdown in dynamic balance
What are the concepts of X-axis displacement and Y-axis displacement distribution?
Vibrations originate from mechanical factors (imbalance, misalignment, rubbing, and looseness, etc.), fluid-related factors (uneven airflow and stall, etc.), and electrical factors (electromagnetic excitation and inter-turn short circuits, etc.).