eSource: Grease Lubrication versus Oil Lubrication

The most common reason for bearing failure is improper lubrication. The lubrication mechanism for grease and oil is the same; oil blended with additives perform the actual lubrication by creating a lubrication film and hydrodynamic lubrication. The difference is the lubrication oil for a grease is suspended in a thickener. The lubrication oil in grease will squeeze out of the thickener under operation pressure.

grease lubrication
09 JAN 2020 ALS
Normally grease lubrication is used or selected if the lubrication requirements of the bearing will allow it. Grease systems are tend to be simpler than oil systems and are less expensive. Often components that move vertically or under heavy loads normally require a grease. Grease works well in bearing applications that operate at moderate speeds where temperatures are not excessively high.

Oil performs better under high speed and extreme friction applications. Also for systems regularly operating at high temperatures an oil circulation systems helps cool the components.

Grease lubrication versus oil lubrication for bearings both have their own specific advantages:

Grease

Oil

Generally manufacturer equipment design will decide whether grease or oil lubrication will be required. When deciding on new equipment installation for industrial applications consideration can be made on equipment bearing design to best optimize lubrication.

Contact ALS Tribology for more information on grease and bearing lubrication.

Written By:

David Doyle, CLS, OMA I, OMA II
Key Accounts and Special Projects
ALS Tribology