Quality judgment measures for FAG bearing installation

After the FAG bearing is installed in the main machine, if the radial runout of the main shaft is measured, it can be found that the measured value of each revolution has a certain change; when the measurement is continuously performed, it can be found that after a certain number of revolutions, the change will be approximately Repeatedly appear. The index for measuring the degree of such change is the cyclic rotation precision, and the change approximately repeats the required number of revolutions to represent the "quasi-period" of the cycle rotation accuracy. The magnitude of the magnitude change in the quasi-period is large, that is, the cycle rotation precision is poor. .

If the spindle is properly preloaded, the speed is gradually reduced to close to the duty speed to implement the "run-in" function of the bearing, which can improve the cycle rotation accuracy of the spindle.

The main factors used for adjustment are installation, use and maintenance, maintenance, etc. in line with technical requirements. According to FAG bearing installation, use, maintenance, maintenance technical requirements, the bearing contact load, speed, temperature, vibration, noise and lubrication status monitoring and inspection, find the abnormality immediately to find the cause, make adjustments to make it back to normal. The installation condition is one of the factors that use the bearing is the primary factor that often causes the change of state between the various parts of the installation package, the abnormal operation state and the early termination of life

    1. Contact fatigue failure
Contact fatigue failure means that the working surface of the FAG bearing is subjected to alternating stress and causes failure. Contact fatigue spalling occurs on the bearing working surface, often accompanied by fatigue cracks, first from the maximum alternating shear stress below the contact surface, and then spread to the surface to form different peeling shapes, such as pitting or pitting. Peeling into small pieces called shallow peeling. Due to the gradual enlargement of the exfoliation surface, it tends to expand deeper and form deep exfoliation. Deep exfoliation is a source of fatigue in contact fatigue failure.
2, wear and tear failure
Wear failure refers to the failure of the relative sliding friction between the surfaces resulting in the continuous wear of the metal on the working surface. Continued wear and tear will cause gradual damage to the bearing components and ultimately lead to loss of FAG bearing dimensional accuracy and other related problems. Wear may affect the shape change, the increase of the clearance and the change of the surface of the working surface may affect the lubricant or cause the pollution to a certain extent, resulting in complete loss of the lubrication function, thus causing the bearing to lose the rotation precision or even the normal operation. Wear failure is one of the common failure modes of various types of bearings. It is usually classified into the most common abrasive wear and adhesive wear according to the form of wear.
1) Instrument detection
Using a spectrometer such as a spectrometer or SPM or a new VIB05 detector to determine the operating state of the bearing to determine whether maintenance or replacement should be performed is the most convenient and reliable method.
For example, when using the VIBO5 detector, this is a microprocessor-based machine state detection instrument with vibration detection, FAG bearing status analysis and infrared temperature measurement. The operation is simple, and the status alarm is automatically indicated. It is very suitable for the field equipment operation and maintenance personnel to detect the equipment status, find problems in time, and ensure the normal and reliable operation of the equipment.
With such an instrument, the bearing working potential can be fully utilized, the bearing warranty can be timely and the failure can be avoided, and it is suitable for young workers to make up for their lack of experience.
2) Manual detection
In places where the above instruments are not available, the equipment can be tested using a medical stethoscope-like monitoring tool. Experienced operators can also use the tools such as round bars or wrenches to resist the outer casing of the machine, and use the ear to monitor through the tool. The sound of the bearing.
The normal FAG bearing operation sound should be uniform, stable and not harsh, and the abnormal bearing operation sound is intermittent, impact or harsh sound.