Jiafei Yan

Applied Tribology in the Bearing

With the development of industry, more and more mechanical parts have been developed toward the direction of high precision, high speed, and high quality.

Bearing Surface Contact

Tribology is the science and engineering of interacting surfaces in relative motion. Solid surfaces (more specifically, interface of solid/gas or solid/liquid) have complex structures and features.

Materials for Bearing Frictional Pairs

The materials of friction pairs affect the bearing operation performance and proper selection of materials for friction pairs plays an important role in the function and application requirements of the machine and also for the working performance and fatigue life of bearings. In this chapter, selecting principles of the friction pair materials and common materials and performance for sliding bearings and rolling bearings will be introduced.

Sliding Bearing Lubrication Theory

Sliding friction exists in the working process of sliding bearing. The advantages of sliding bearing include the stability, reliability, and noiseless. Requirement of the formation of lubrication film is to ensure the sufficient lubricant for the sliding bearing. Under the condition of liquid lubrication, the surfaces of the sliding bearing are separated by lubricating oil and there is direct contact, so the friction loss and the wear of the surface can be reduced greatly. Besides, the lubricating film also has a certain vibration absorbed performance. In this chapter, the basic theory of sliding bearing lubrication will be introduced, on bases of which the reasons of sliding bearing lubrication failure can be analyzed further, and finally, establish the foundation for seeking the effective way to solve the problem.

Mechanism of Bearing Friction and Wear

Research on mechanism of bearing friction and wear is mainly involved with physics, chemical, metallurgical, and mechanical functions between the surfaces with relative motion and interaction in bearings.

Bearing Lubrication Application

Lubrication has an important influence on the bearing fatigue life, friction, wear, temperature, and vibration. Bearings cannot work without normal lubrication. It can be found that about 40 % of the bearing damage is related to poor lubrication by analyzing the causes to the damage of the bearing.

Rolling Bearing Lubrication Theory

If the lubrication between the rolling element and raceway for the rolling bearing is insufficient, scratches, pitting, and scuffing to different extend will be caused on the rolling elements and raceway, meanwhile, whether the proper lubricant film can be formed or not is important for the fatigue lifetime of the contact area between the rolling elements and the raceway.

Friction and Wear Testing Technology in the Bearing

Equipments are often broken because of the friction and wear of bearing under the condition of high speed, high temperature, and heavy load.

Fault Diagnosis and Status Monitoring of the Bearing

Bearings are widely used in the mechanical equipment and whose working condition is directly related to the operation states of the rotating elements.