Lateral Vibration Analysis

Lateral vibration Analysis

Lateral vibration of a shaft rotor is due to instability, unbalance, or other forces acting on the rotor. Lateral Analysis (also called Rotordynamics Analysis) simulates the rotating system, calculates the critical speeds, predicts vibration amplitudes, and provides recommendations to reduce vibration risks.

SCOPE OF WORK: ANALYSIS FEATURES

The scope is API Compliant (including but not limited to 610, 617, 619, and RP 684). The modeling and analysis include these activities:

Undamped Critical Speed Analysis

• Prepare the rotor dynamic model to simulate the entire system.
• Determine critical speeds over a range of bearing stiffnesses.
• Calculate the mode shapes, eigenvalues, and critical speeds.

Damped Eigenvalue (Critical Speed) Analysis

• Calculate modes across the speed range.
• Damped eigenvalue analysis of critical speeds of the rotor with the actual bearing stiffness and damping coefficients; damping evaluated using several methods.
• Separation margins evaluated per API requirements usually 10% to 15% depending on other factors.

Forced Response Analysis

• Calculate the unbalanced vibration response amplitudes and critical speed locations based on API recommended unbalanced guidelines.
• Evaluate the separation margins for a range of bearing clearances.