Vibration Analysis

Condition-monitoring technique · Updated 2026-07-15

Vibration analysis measures the vibration signature of rotating equipment and decomposes it by frequency to identify faults such as imbalance, misalignment, bearing wear and looseness — often weeks before failure. It is the workhorse technique of predictive maintenance for rotating machines.

How it works

Accelerometers capture the vibration signal, which is transformed (typically via FFT) into a frequency spectrum. Because each fault type excites characteristic frequencies — running speed for imbalance, twice running speed for misalignment, bearing-defect frequencies for bearing wear — the spectrum reveals not just that something is wrong but what and how severe. Trending the signal against a baseline turns a vague 'it sounds rough' into a dated, prioritised work order.

What the data shows

Rising amplitude at running speed points to imbalance; high vibration at twice running speed suggests misalignment; energy at specific bearing-defect frequencies indicates bearing wear; broadband high-frequency noise can mean lubrication problems or, on pumps, cavitation.

Vibration Analysis in practice

Vibration Analysis is versatile because it works across many asset types: pumps, electric motors, fans and blowers and others. This breadth is both a strength and a consideration — a wide-ranging technique often requires less customization, but may not be as specialized as a dedicated point-solution. Most plants use Vibration Analysis in combination with other techniques to build a complete condition-monitoring programme.

In practice: Vibration Analysis excels at catching developing faults early, when they show as subtle changes in the monitored signal. The challenge is distinguishing a real fault signal from noise. Successful Vibration Analysis programmes typically combine threshold alarms (alert if the signal exceeds a limit) with trending analysis (alert if the signal is rising fast, even if still below the limit). Both approaches matter for reliability.

Getting started: Implement Vibration Analysis on your most critical assets first — those whose failure causes the longest downtime or highest cost. Start with one or two assets to learn the signals on your equipment and processes, then expand. Many plants find that Vibration Analysis baseline data (what 'normal' looks like) takes 2–4 weeks to establish, after which the technique pays for itself through early fault detection.

Vibration Analysis by equipment

Glossary: Vibration Analysis →