Project: Oil Mist Lubrication and its effect on the performance of contacting face type bearing isolator
Sponsor: Industry
: LSU, Mechanical Engineering
Principal Investigator: Dr. Michael Khonsari
Graduate Students: Hrishikesh R. Gadre, David R. Hertel
Contact Information: Dr. Michael Khonsari


With developing technology, speeds of rotating equipment in industry are on increase. At such high speeds, lubrication can be a problem since grease lubrication is not feasible and in oil sump lubrication, too much heat is generated through fluid friction which makes its use impractical. Oil Mist Lubrication provides a viable solution in such cases. It is a centralized lubrication system where in the lubricating oil is transformed into the form of oil mist using the energy of compressed air and this oil mist generated by a single generator can be supplied to number of locations in a plant over long distances. This system has many advantages over conventional sump lubrication method and hence is being used widely in recent years.

Operating life of a bearing is most of the times limited by its failure which occurs due to contamination of lubricating oil and so, the actual bearing life hardly reaches its fatigue life. Bearings operating with clean uncontaminated oil run much longer before failure than bearings operating in harsh situations. Also, with increasing environmental regulations, it is becoming more important to minimize oil leaks from machinery. For both of these problems, Bearing Isolator provides the solution. As the name indicates, it is used to isolate the bearings from the outside world. It is meant to seal in both the directions, i.e. prevent the lubricating oil from leaking out of the bearing housing onto the equipment base plate and also to keep moisture, external airborne contaminants, and dirt out of the bearing housing.

Project description:

A testing program is being done at CeRoM on currently available bearing isolator face materials for wear rates, coefficient of friction, and interface temperature during both dry running and in an oil mist environment. Testing samples of both the faces conforming to ASTM D3702 are tested on a vertical type tribometer and real time values of wear, friction and temperature are recorded for different tests with different combinations of pressure and speed.

A special attachment has been designed to provide the oil mist environment near the contacting faces. It has two ports, one for the entry of oil mist which is provided by the oil mist generator and the other for the return of the condensed oil back to the reservoir of the generator.

By studying materials, geometry, and other design features, CeRoM hopes to advance the state of the art for bearing isolators.

The objectives of this research:

1. Measure wear rates of testing samples of contacting seal faces, to predict service life.
2. Observe the effect of introduction of oil mist environment on the performance of bearing isolator.
3. Investigate potential bearing isolator design improvements for reduced friction, operating temperature, wear rate and for extended service life.


Anticipated Benefits:

1. Ability to predict service life at various conditions, for bearing isolators with contacting seal faces.
2. Extend size and speed limits of currently available bearing isolators.
3. Develop potential bearing isolator design improvements











Site Designed By: Anil Kumar Lakky Reddy