determining actual maximum vibration amplitude (requires xy proximity probes)
vibration precession; vibration either in the direction of or opposite of the direction of rotation (requires xy proximity probes)
shaft average centerline radial position (requires xy proximity probes)
full spectrum (requires xy proximity probes)
At a minimum, the risk assessment should include:
• Quantify past and present unit performance, maintenance history, and unit availability.
• Review existing data relative to any previous failures, maintenance history and unit availability.
• Quantify expected return on investment of expected changes or improvements.
 A fixed mass at a fixed radius rotating at operating speed generating a constant, uniform force in all directions
Nnon-uniform support stiffness; i.e. different vertical support stiffness vs. horizontal stiffness.