
Poor Fitting [16%]
About 16% of all premature bearing failures are caused by
1. Poor fitting (usually brute force ...)
2. Being unaware of the availability of the correct and proper fitting tools
3. Laziness

The use of specialised tools, equipments and techniques will make the above job easier, faster and more cost effective.
These is one positive step towards long bearing life, thurs achieving maximum compressor uptime.
Poor Lubrication [36%]
About 36% of premature bearing failures are caused by incorrect specification and inadequate application of the lubrication.

Effective lubrication, using recommended lubrication [grease, oil, coolant], Special tools, equipments, and techniques, really helps to greatly reduce downtime.
Contamination [14%]

Bearings are precision components that will not operate efficiently, unless both the bearings and its lubricants are isolated from contamination. At least 14% of all premature bearing failures are attributed to contamination.
Fatigue [34%]
Whenever compressors are overloaded, incorrectly serviced or neglected, bearings will suffer, resulting in 34% of all premature bearing failures.

Condition Monitoring Equipment
CME includes hand-held instruments, hard-wired systems and data management software for periodic or continuous monitoring of key parameters.
edited from
http://www.skf.com