The bearing normally can be used up to the end of the rolling fatigue life if handled properly. If it fails earlier, it may caused by improper mounting, mishandling, poor lubrication, entry of foreign matter or abnormal heat generation. Considering possible causes of bearing failure and damages according to the condition of the machine on which the bearings failed and taking countermeasures is very important to prevent the recurrence of similar problems.
Following types of damage typically encountered are presented in the table below.
| Damage type | Possible Causes | Solutions |
| Flaking | ● Over and excessive load | ● Find out the cause of the heavy load |
| ● Improper handling and mounting | ● Examine operating conditions | |
| ● Poor shaft or housing accuracy etc. | ● Improve the mounting method (shrink fit, use proper tools) | |
| ● Unsuitable bearing clearance | ● Check the precision of shaft and housing | |
| ● Installation error etc. | ● Check the bearing internal clearance | |
| Speckles | ● Ingress of foreign particles | ● Improvement in sealing |
| ● Improvement of the operating environment if possible | ||
| ● Filtration of the oil or grease | ||
| Cracking | ● Excessive load | ● Find out the source of very large load |
| ● Excessive impacts | ||
| ● Rapid cooling | ● Improve the installation process | |
| ● Excessive interference | ● Correct the interference | |
| ● Overheating by creeping | ● Prevent the creep | |
| ● Very loose fit | ||
| ● Large flaking etc. | ||
| Rust and Corrosion | ● Ingress of water or corrosive material (such as acid) | ● Do not use bad quality varnish |
| ● Condensation of moisture contained in the air | ● Dry the varnish properly with sufficient time | |
| ● Poor packaging and storing conditions | ● Improvement in sealing effect | |
| ● Handling with bare hands etc. | ● Careful handling of bearing | |
| Mounting Flaws | ● Inclination of inner and outer rings during mounting or dismounting. | ● Use appropriate jig and tool |
| ● Shock load during mounting or dismounting | ● Avoid a shock load by use of a press machine | |
| ● Center the relative mating parts during mounting | ||
| Eletrical Corrosion | ● Electrical potential difference between inner and outer rings | ● Design electric circuits which prevent current flow through the bearings |
| ● Electrical potential difference of a high frequency that is generated by instruments or substrates when used near a bearing | ● Insulation of the bearing | |
| Seizure | ● The grease’s maximum working temperature is lower than the actual temperature and the grease get failure. | ● Selection of suitable lubricant grease |
| ● Excessive rotational speed | ● Improve dissipation of heat from the bearing | |
| ● Dissipation of heat generated by bearing is not enough. | ● Improvement in clearance and preload | |
| ● Clearance too small. | ● Improvement in operating conditions | |
| ● Excessive load (or preload) | ||
| ● Installation error etc. | ||
| Fracture | ● Impact during mounting | ● Improve the mounting method (shrink fit, use proper tools) |
| ● Excessive load | ● Reconsider the load conditions | |
| ● Poor handling such as dropping | ● Provide enough back-up and support for the bearing rib. | |
| Fretting | ● Poor lubrication | ● Use a proper lubricant |
| ● Vibration with a small amplitude | ● Apply a preload | |
| ● Insufficient interference | ● Check the interference fit | |
| ● Apply a film of lubricant to the fitting surface | ||
| Cage Damage | ● Poor mounting (Bearing misalignment) | ● Check the mounting method |
| ● Large moment load | ● Check the temperature,rotation, and load conditions | |
| ● Shock and large vibration | ● Reduce the vibration | |
| ● Excessive rotation speed,sudden acceleration and deceleration | ● Select a cage type | |
| ● Poor lubrication | ● Select a lubrication method and lubricant | |
| ● Temperature rise |
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