Rolling bearings in the use of the process showed a strong regularity, and repeatability is very good. Normal high-quality bearings at the beginning of use, vibration and noise are relatively small, but the spectrum of some scattered, the amplitude is small, may be due to some defects in the manufacturing process, such as surface burr. After a period of movement, vibration and noise to maintain a certain level, the spectrum is very simple, only one or two times the frequency。 Rarely appear more than three times the frequency spectrum, the bearing state is very stable, into a stable working period.
Continue to run into the late use, bearing vibration and noise began to increase, sometimes abnormal sound, but the vibration changes more slowly, this time, the bearing kurtosis value began to reach a certain value. We believe that this time the bearing that is the initial failure.
At this time, it is required to monitor the bearing closely, pay close attention to its changes. After that, the bearing kurtosis value began to decline rapidly, and close to the normal value, while the vibration and noise began to increase significantly, the increase began to accelerate, when the vibration exceeds the vibration standard (such as ISO2372 standard), the bearing kurtosis value also began Rapid increase, when more than the vibration standard, and the kurtosis value also exceeds the normal value (available kurtosis relative standard), we believe that the bearing has entered a late fault production, the need for timely maintenance of equipment, replacement of rolling bearings.
Bearing the performance of the late fault characteristics to a serious failure (usually bearing damage such as axle, burns, sand spalling, roller, bead wear, etc。) most of the time not more than a week, the greater the capacity of equipment, the faster, The shorter the interval。 Therefore, in the actual rolling bearing fault diagnosis, once the late fault characteristics, should be determined to determine the bearing failure, as soon as possible arrangements for maintenance.