Combination fluid film journal/thrust bearing

Bearing Business

By Barry Blair, Waukesha Bearings
Published in Processing magazine, May 2016

Bearings are a critical component in equipment reliability, efficiency and life. The majority of rotating process equipment today relies on rolling element bearings or fluid film bearings to counteract gravity and other forces in the equipment and allow the shaft to rotate freely. Selecting the right bearing for the equipment and application is essential to the successful operation of that equipment.

A key difference between rolling element bearings and fluid film bearings when it comes to process equipment maintenance is the expected life of the bearings. Rolling element bearings typically have a predictable life based on the operating conditions. When properly designed and maintained, fluid film bearings can operate for decades.

The proper selection of materials and mechanical design is the foundation for a fluid film bearing’s long life. Typical factors that affect material selection include load, speed, operating temperature, insulation requirements, and lubricant type and cleanliness. Depending on the requirements, material options include babbitt (also known as whitemetal), bronze, aluminum tin, polymer, ceramic, cermet and diamond.

For the mechanical design, the fluid film bearing designer must not only consider the proper sizing of the bearing to handle the loads and minimize the power loss but also incorporate features to optimize the formation of film and tune the dynamic characteristics of the bearing. Tuning the bearing’s characteristics improves the performance of the process equipment.

For more detail about material selection and bearing design factors, continue reading the article in the May 2016 issue of Processing magazine or online at

May 19, 2016 | Article