Bearing Failure Symptom Triage - Diagnostic Decision Helper
Identify likely bearing failure causes from observed symptoms, noise patterns, and visual inspection findings
Free bearing failure diagnostic tool that helps maintenance teams identify the most likely cause of bearing problems from observed symptoms. Select the symptoms you are seeing - noise type (rumble, squeal, clicking, grinding), vibration characteristics (overall high, periodic, random), temperature behavior (running hot, sudden increase, fluctuating), and visual inspection findings (spalling, discoloration, cage damage, contamination, corrosion). The diagnostic engine cross-references your symptoms against common bearing failure modes: fatigue spalling, inadequate lubrication, contamination, misalignment, overload, electrical damage (fluting), corrosion, and improper mounting. Each diagnosed cause includes a confidence level, explanation of the failure mechanism, and recommended corrective actions to prevent recurrence. This is not a vibration analyzer - it is a structured diagnostic aid for maintenance teams who need to quickly narrow down the cause of a bearing failure and take the right corrective action rather than just replacing the bearing and hoping the problem does not come back.
Check if the bearing was running over its speed limit -- a common hidden cause of early failure
Bearing Speed Limit Checker →Verify that grease type and regreasing interval were adequate for the speed and temperature
Bearing Grease Speed Factor Guide →Screen shaft-fit prompts when reviewing creep, fretting, or preload clues
Press Fit / Clearance Checker →Check vibration severity readings to correlate symptoms with ISO 10816 alarm thresholds
Vibration Severity Checker →How It Works
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Describe the Noise
Select the type of noise observed: rumbling or growling (suggests spalling or contamination), high-pitched squeal (suggests lubrication starvation), rhythmic clicking (suggests rolling element or cage damage), grinding (suggests severe wear or contamination), or no abnormal noise.
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Describe Vibration
Select vibration characteristics: overall vibration increase (general degradation), periodic vibration at shaft speed or harmonics (misalignment or unbalance), random vibration spikes (contamination or cage damage), or vibration at bearing frequencies (BPFO, BPFI, BSF).
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Describe Temperature
Select temperature behavior: running hotter than normal (lubrication or preload), sudden temperature spike (lubrication failure or seizure), temperature fluctuations (intermittent contact or lubricant issues), or normal temperature.
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Describe Visual Findings
Select what you see on the bearing and shaft: spalling or flaking, discoloration, cage damage, contamination (particles, water), corrosion or rust, fretting marks on the shaft, electrical fluting marks, or no visible damage.
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Review Diagnosis
Get a ranked list of likely failure causes with confidence levels, failure mechanism explanations, and specific corrective actions. The most likely causes appear first based on symptom matching.
Built For
- Maintenance mechanics diagnosing bearing failures during equipment repair
- Reliability engineers conducting root cause failure analysis on recurring bearing problems
- Maintenance supervisors training staff on bearing failure recognition and diagnosis
- Predictive maintenance teams correlating vibration data with bearing condition
- Plant engineers investigating chronic bearing failures on specific equipment
Assumptions
- Failure mode identification is based on visual symptoms and operating condition descriptions per ISO 15243 classifications.
- The user can accurately describe or photograph the bearing damage pattern (spalling, flaking, discoloration, cage damage, etc.).
- Operating history (load, speed, lubrication, contamination exposure) is approximately known by the user.
- The bearing was correctly installed and had appropriate fit, clearance, and lubrication at startup.
Limitations
- Visual triage cannot confirm root cause with the same certainty as metallurgical cross-section analysis.
- Multiple simultaneous failure modes (e.g., contamination plus misalignment) may produce overlapping symptoms.
- Electrical discharge damage (fluting, frosting) from VFD-driven motors requires specialized analysis.
- Subsurface fatigue initiation from inclusions or material defects is not detectable from external visual inspection.
References
- ISO 15243 - Rolling Bearings: Damage and Failures, Terms, Characteristics, and Causes
- SKF - Bearing Damage and Failure Analysis (technical publication)
- FAG/Schaeffler - Rolling Bearing Damage: Recognition of Damage and Bearing Inspection (Publ. WL 82 102)
- Timken - Bearing Damage Analysis Reference Guide