What instruments can be used to monitor the operating condition of deep groove ball bearings?

The operation status monitoring of deep groove ball bearings requires the use of professional instruments for multi-dimensional data collection. The following are the monitoring instruments classified by function and their technical features, along with practical scenarios and selection suggestions:
1. Vibration and noise monitoring instruments
1. Portable vibration meter
Core function: Measure the acceleration, velocity, and displacement values of the bearing, and analyze spectral characteristics (such as FFT spectrum diagrams).
Typical models:
Furukawa 810 (acceleration range ±50g, resolution 0.01g);
Riken VM-82 (supports ISO 10816 standard vibration level judgment).
Application scenarios: Regular inspections of equipment such as fans and motors. Judging raceway wear or ball failure based on sudden changes in vibration values (such as acceleration > 4.5g).
2. Vibration analyzer (spectrometer)
Technical advantages: Can identify characteristic frequencies of the bearing (such as the fault frequency of the outer ring BPFO, the fault frequency of the inner ring BPFI), and locate the specific damaged area.
Case study: When a steel mill rolling mill bearing made a strange noise, the spectrometer detected a peak at 126Hz (corresponding to BPFO = 125.7Hz), confirming the peeling of the outer ring.
Representative products: Swedish VMI Master Series, American CSI 2130.
3. Ultrasonic detector
Working principle: Capturing high-frequency sound waves (20-100kHz) generated when the bearing is poorly lubricated or in early wear.
Typical applications:
Lubrication failure warning: Normal bearing ultrasonic value < 40dB, when > 60dB, it indicates the failure of lubricating grease;
Early crack detection: The ultrasonic signal generated by the metal surface micro-cracks is 15-20dB higher than that of a normal bearing.
2. Temperature and thermal imaging monitoring
1. Infrared thermometer Technical Specifications:
Temperature measurement range: -30℃ to 500℃ (for high-temperature models, it can reach 1200℃);
Accuracy: ±2℃ or ±2% (whichever is greater).
Key points for use: When measuring the surface of the bearing housing, the ratio of distance to the spot diameter (D:S) should be ≥ 10:1 (for example, if the distance is 10cm, the spot diameter should be ≤ 1cm). Avoid interference from environmental radiation.
2. Infrared thermal imager
Visual advantages: Generate temperature distribution heat maps to quickly locate local overheating areas of the bearing (such as unilateral high temperature caused by installation eccentricity).
Data cases: The temperature of the outer ring of a paper machine bearing was abnormal. The thermal imager showed that the temperature at 3 points was 15℃ higher than other areas. Eventually, a scratch on the raceway of this bearing was found.
Main models: American FLIR T1040 (resolution 640×512), German Testo 890.
III. Displacement and Accuracy Monitoring Equipment
1. Micrometer (percentage gauge)
Mechanical measurement: Used for static clearance and rotational accuracy detection, such as:
Radial clearance: Fix the inner ring and push the outer ring to measure the radial displacement (for 6206 bearings, the standard clearance is 13-34μm, and it needs to be replaced if it exceeds 50μm);
End face runout: When the main shaft bearing is installed, if the end face runout is >0.02mm, it affects the processing accuracy.
2. Laser alignment instrument
Indirect monitoring: Abnormal wear of the bearing can cause shaft system deviation. By measuring the shaft deviation with a laser alignment instrument (such as Swedish Easy-Laser E960), when the radial deviation >0.1mm/m or the angle deviation >0.1°, it may be caused by bearing failure.
IV. Comprehensive Performance Monitoring System
1. Online monitoring system (PLC integrated)
System composition: vibration sensor (such as IEPE acceleration sensor) + temperature sensor + data acquisition module (such as PLC analog input module).
Alarm logic:
When the vibration value exceeds the set threshold (such as 3.5g), output DI signal;
When the temperature is >80℃, trigger audible and visual alarm.
Application scenarios: Continuous production equipment (such as petrochemical reaction vessel agitator), real-time monitoring 24 hours a day.
2. Oil analysis instrument
Indirect detection: Analyze the iron content (Fe) in the lubricating oil through a spectrometer (such as American PE Optima 8000). When the Fe concentration >50ppm, it indicates bearing metal wear.