Les bases de l'analyse des vibrations : comment les machines tournantes vous indiquent qu'elles sont sur le point de tomber en panne

Key takeaways

• Vibration analysis = monitoring rotating-equipment vibration signatures to predict failure.
• Most rotating-equipment failures are predicted by vibration changes weeks before breakdown.
• Common signatures: imbalance (1x running speed), misalignment (2x), bearing defects (high frequency).
• Triggers: rising amplitude, characteristic frequency emergence, comparison to historical baseline.
• Worth the investment on critical rotating equipment. Less valuable on stationary or simple assets.

Short answer: Vibration analysis monitors rotating-equipment vibration signatures to predict failure. Most rotating-equipment failures change vibration patterns weeks before breakdown. Common patterns: imbalance shows at running speed, misalignment at twice running speed, bearing defects at high frequency. Triggers for action: rising amplitude, new characteristic frequencies, deviation from historical baseline. Worth the investment on critical rotating equipment. See also Infrared Thermography Basics.

Why vibration carries failure signal

Rotating equipment in good condition vibrates predictably:

• Some vibration at running speed (always present).
• Low amplitude.
• Stable spectrum over time.

Failures change the pattern:

• Imbalance increases vibration at 1x running speed.
• Misalignment generates 2x running speed component.
• Bearing wear generates high-frequency content.
• Looseness produces broadband noise.

The patterns are characteristic; analysis identifies the failure mode before it produces a breakdown.

What is measured

• Amplitude. How much vibration (mm/s, g, or microns).
• Frequency. What frequencies dominate.
• Trend. Change over time.
• Phase. Relative timing (used in balancing).

Most plants start with amplitude and frequency analysis. Phase analysis is for balancing work.

The common signatures

Imbalance: high amplitude at 1x running speed. Cause: unbalanced rotor.

Misalignment: 2x running speed component. Cause: coupling misalignment.

Bent shaft: 1x and 2x with phase characteristics. Cause: bent or warped shaft.

Looseness: broadband content, fractional harmonics. Cause: loose mounting or worn parts.

Bearing defects: high-frequency content (5x running speed and higher). Cause: bearing element damage.

Gear mesh problems: tooth-mesh frequency (gear teeth x running speed). Cause: gear wear.

What triggers action

1. Amplitude above ISO 10816 alarm thresholds. Industry standards for machine condition.
2. Rising trend. Even within thresholds, persistent rise indicates degradation.
3. New characteristic frequency. A spectrum component that was not there before.
4. Pattern matching a known failure mode. Bearing signature emerging.

Action: investigate, schedule maintenance, plan replacement.

How vibration monitoring is deployed

Walk-around route. Technician with handheld analyzer reads each asset on a route. Common for medium-criticality assets.

Wireless sensors. Battery-powered sensors send periodic readings. Common for hard-to-reach assets.

Online continuous monitoring. Wired sensors stream real-time data. Common for critical assets.

Cost and value scale with deployment method.

What vibration analysis cannot do

• Predict non-vibration failures (electrical, control, software).
• Catch sudden failures (impacts, debris).
• Replace operator inspection (vibration misses many visible issues).
• Work on stationary equipment.

Vibration is one tool, not the whole solution.

What it works well on

• Motors.
• Pumps.
• Compressors.
• Fans.
• Gearboxes.
• Turbines.

Rotating equipment with bearings, gears, or imbalance risk.

Common mistakes

1. Vibration data without analysis. Sensors deployed; nobody interprets. Data piles up; alerts ignored.

2. Threshold-only alerting. Misses trend signals. Use both.

3. No baseline. Without historical comparison, current readings are unanchored.

4. Universal monitoring. Vibration on cheap assets does not pay back.

Integration with CMMS

Vibration alerts should:

• Generate WO automatically on threshold breach.
• Route to reliability engineer.
• Track investigation and resolution.
• Update asset history with findings.

Without CMMS integration, alerts go to email and get lost.

Cost considerations

Walk-around analyzer: €3,000-10,000 plus technician time.

Wireless sensors: €200-500 per point.

Online continuous: €1,000-5,000 per point plus infrastructure.

Scale to criticality. Critical assets get continuous; mid get wireless; lower-criticality get walk-around.

How OEE connects

Vibration catches failures before they produce downtime. Plants with mature vibration programs see Availability move up as catches translate to planned vs unplanned response.

How a modern CMMS supports vibration

A modern CMMS integrates with vibration monitoring systems, generates WOs on alerts, tracks the resolution, and updates asset history with findings.

Fabrico's CMMS integrates with vibration monitoring systems, generates condition-driven WOs, and updates asset history with vibration-driven findings.

See how Fabrico captures this automatically — explore OEE for manufacturing or book a demo.

Related reading

• Infrared Thermography Basics

Frequently asked questions

How early does vibration catch failure?

Weeks for bearings; days for some imbalance issues. Depends on degradation rate.

Do I need a vibration analyst on staff?

For mature programs yes. For starting, contract analysis is common.

What is ISO 10816?

Vibration standard with severity zones (A through D) for different machine classes.

Should I monitor every motor?

Critical and important motors yes. Cheap motors with redundancy may not pay back.

Is AI vibration analysis useful?

Increasingly. Trained models catch patterns that thresholds miss.