Darbar Company
Power Transmission Solutions


Tips, Practices, and More

Bearing Maintenance From Start to Finish (Part 3)

Proper Bearing Maintenance

For any type of bearing in rotating machinery, applying best maintenance practices and using the correct enabling tools can help contribute to maximum bearing service life.

Bearings should always be properly stored, mounted, adequately lubricated when and where required, monitored, dismounted, and ultimately inspected to uncover root causes of any damage.

While particular applications will present unique factors influencing a bearing’s service life, the following maintenance-oriented guideline can substantially improve the life of bearing.

Turning to bearings in service

In service, sufficient lubrication is essential. Maintenance goals: Deliver the right lubricant in the right amount at the right time.

Among lubricant delivery methods, manual lubrication (with grease gun) typically can present major challenges for maintenance technicians if the appropriate tools, practices, and knowledge are absent – and reliability can further be affected by under- or over-greasing. As a practical alternative, automatic lubrication can be employed to provide quantities of clean lubricant on a regular basis, while increasing safety and saving time for staff. Ready-to-use or tailored systems can be engaged, depending on application, lubricating points, and similar considerations.

Over time, the lubricant in a bearing arrangement gradually will lose its lubricating properties due to mechanical work, aging, and/or the buildup of contamination. This underscores a maintenance-related necessity for grease to be replenished or renewed and for oil to be filtered and changed at regular intervals to help promote maximum bearing service life.

To gain long bearing life it is imperative to determine the condition of machinery and bearings while in operation. This can be accomplished with a process known as “condition monitoring.”

Condition monitoring allows for the repair of components detected as problematic prior to their failure. This is accomplished by performing condition-based maintenance. The approach not only reduces the possibility of catastrophic failure, but also allows plant personnel to order parts in advance, schedule manpower, and plan unrelated repairs during the downtime.

The most significant machine-condition parameters to help monitor the health of a bearing include (in no specific order) noise, temperature, speed, vibration, and alignment. A variety of measuring instruments will enable users to analyze all factors.

When a bearing must be taken out of service, for whatever reason, proper dismounting practices should be followed.

One reason for dismounting an old bearing is to replace it with a new one. When proceeding, care must be taken not to damage the shaft in the process, which can result in compromising a machine's efficiency. A damaged shaft can greatly influence the service life of the new bearing.

Another reason to dismount bearings is for maintenance or replacement of other machine components. Since these dismounted bearings will be mounted again (unless they are damaged during dismounting), proper dismounting methods and tools should be enlisted. Choice of tools will depend on bearing type, size, and fit.

In situations where a bearing must be replaced due to premature failure, detective work focusing on bearing and grease analysis can help point to root causes. Among common root causes: inadequate lubrication, contamination, errors in mounting/dismounting, and/or electrical damage. Pinpointing the actual cause(s) will help prevent a repeat of history.

When it comes to bearing maintenance, every decision and practice can impact a bearing’s performance, reliability, economy, and service life. Partnering with an experienced bearing manufacturer can open the door to the knowledge and technologies that will support maximized bearing life and reduced maintenance time, labor, and costs.