The development process and stages of classic bearing faults

1、 Process changes of bearing failure

The deterioration of bearing faults does not follow a linear pattern, but rather an exponential pattern, as shown in the following figure:

2、 Development stage of bearing failure

1. Initial stage

The noise is normal;

Normal temperature;

Ultrasonic, vibration peak energy, and acoustic emission measurements can be used to detect defects in the outer ring of the bearing;

The total amount of vibration is relatively small, and there are no discrete peaks in the frequency of bearing faults;

The remaining lifespan is greater than 10%.

2. Phase 2

Slight increase in noise;

Normal temperature;

Ultrasound, acoustic emission, significant increase in vibration peak energy, and defects in the outer ring of the bearing;

The total amount of vibration slightly increases (total amount of vibration acceleration and total amount of vibration velocity);

On the logarithmic scale spectrum, the bearing fault frequency can be clearly seen, while on the linear scale spectrum, it is rare to see it. The noise level has significantly increased;

The remaining lifespan is 5%.

3. Phase Three

Audible noise;

The temperature slightly increases;

Very high ultrasound, acoustic emission, vibration peak energy, and bearing outer ring malfunction;

There is a significant increase in the total amount of vibration acceleration and vibration velocity;

Clearly identify the bearing fault frequency, its harmonics, and sidebands on the linear scale spectrum;

The vibration spectrum noise level is significantly improved;

The remaining lifespan is less than 1%.

4. Phase Four

Changes in the intensity of noise;

The temperature has significantly increased;

Ultrasound, acoustic emission, and vibration peak energy rapidly increase and then gradually decrease, and the outer ring of the bearing is in a faulty state before damage;

The total vibration velocity and displacement significantly increase, while the total vibration acceleration decreases;

The vibration peaks dominated by lower bearing failure frequencies have very high noise levels in the vibration cheek spectrum;

The remaining lifespan is less than 0.2%.