Mechanical Engineering, KFUPM 1  BASIC MACHINERY VIBRATIONS Yehia A. Khulief, P.E.* Professor Department of Mechanical Engineering, King Fahd University of Petroleum & Minerals KFUPM Box 1767, Dhahran, Saudi Arabia * State of Alabama, USA

Mechanical Engineering, KFUPM 2   VIBRATION DIAGNOSTICS VIBRATION DIAGNOSTICS science technology art

Mechanical Engineering, KFUPM 3  VIBRATION DIAGNOSTICS VIBRATION DIAGNOSTICS  Have an understanding of the machinery design  Have an understanding of the machinery operating dynamics.  Proper vibration measurementsmeasurements  Ensure accurate data collection For successful diagnostics and trouble shooting of rotating machinery, the Vibration Analyst must: rotating machinery, the Vibration Analyst must:

Mechanical Engineering, KFUPM 4  Understand Data Representation e.g. Frequency versus Time Domain time Amplitude (power) frequency Time domain Measurements Frequency Domain Measurements

Mechanical Engineering, KFUPM 5  Understand Data Representation Spectrum Spectral Lines Spectral lines are representations of a single component of a waveform in the frequency domain. The line's height represents the component's amplitude. A spectrum is a curve connecting these lines. You do not see individual spectral lines in a Spectrum Plot, or in other asynchronous waveform plots, only the spectrum curves. Asynchronous waveform plots use 50, 100, 200 or 400 spectral lines over a range of frequencies. You specify both the number of lines and the frequency span in the Spectrum Sample Rate Configuration phase

Mechanical Engineering, KFUPM 6  Understand Data Representation How to Analyze Spectrum Common Data Format

Mechanical Engineering, KFUPM 7   IMBALANCE IMBALANCE  MISALIGNMENT  LOOSENESS  RESONANCE  RUBBING  BEARINGS  GEARS  MOTORS  VANE PASSING  BELTS & PULLEYS  OIL WHIRL  FANS & DUCTS  PIPING  CAVITATION  BEATS  SOFT FOOT  SYMPATHATIC  CRACKED  CRACKED SHAFT Major Causes of Vibration

Mechanical Engineering, KFUPM 8   Thank you