How to diagnose common operating failures of Flange Series Deep Groove Ball Bearing?

In industrial transmission systems, Flange Series Deep Groove Ball Bearing is a core supporting component, and its operating status directly affects the performance and service life of the equipment.
1. Spectrum diagnosis of abnormal noise
When metal friction sound (frequency 800-2000Hz) or irregular impact sound occurs during bearing operation, priority should be given to troubleshooting:
Lubrication status: Use a grease quantitative detector to measure the lubricant content. When the NLGI consistency value deviates from the standard by 15%, relubrication is required
Foreign matter intrusion: Use an endoscope to observe the cage gap, and use oil iron spectrum analysis to detect the metal particle concentration (>200ppm requires immediate shutdown)
Installation error: Use a laser alignment instrument to measure the flange end face runout, and the allowable tolerance should be less than 0.05mm/100mm
2. Progressive troubleshooting of abnormal temperature rise
When the surface temperature of the bearing seat exceeds the ambient temperature by +40℃ (or the absolute value is >80℃):
Over-lubrication diagnosis: Check whether the seal ring exhaust hole is blocked and measure the grease filling amount (recommended to be 30-50% of the free space)
Abnormal clearance verification: Measure the axial clearance with a feeler gauge and compare it with SKF C0/C3 standard clearance table
Load overload analysis: Use dynamic torque sensor to monitor actual load and compare with bearing rated dynamic load (20% safety margin is required)
III. Intelligent analysis of vibration signal
Use vibration spectrum analyzer (recommended sampling frequency ≥20kHz) to monitor:
Characteristic frequency identification
Frequency of cage failure: 0.38×RPM×(1-d/D×cosα)
Frequency of raceway damage: 0.4×RPM×(Z±1)
Kurtosis index monitoring: When Kurtosis value>5, it indicates early surface peeling
Envelope demodulation analysis: Capture impact signals in the high frequency band of 200-2000Hz
IV. Chemical diagnosis of lubrication failure
Regular sampling and testing of lubricant performance parameters:
Acid value change: When the TAN value increase>0.5mg KOH/g, the grease needs to be replaced
Water content: Detected by Karl Fischer method, controlled <0.03%
Oxidation stability: Rotating oxygen bomb test time <100 minutes indicates additive failure
V. Systematic diagnostic process (according to ISO 13373-1 standard):
Preliminary inspection: visual seal integrity → manual rotation test → basic vibration detection
Step-by-step elimination: temperature field mapping → acoustic emission detection → dynamic resistance measurement (diagnosing electrical corrosion)
Data verification: establish a bearing life cycle database and compare historical operating parameter curves
By implementing this diagnostic system, the accuracy of flange bearing fault identification can be increased to more than 92% (based on ABB's field data). It is recommended that companies establish a case library containing 200+ fault characteristics, combine the condition monitoring system to achieve predictive maintenance, and reduce unplanned downtime losses by more than 60%. The improvement of equipment reliability is never accidental, but comes from the precise control of the details of each bearing operation.