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The pressure generation within the lubricant fluid present in the clearance between a thrust bearing and the collar attached to the shaft has a fundamental importance to avoid contact between solid parts with axial relative motion. Any existing contact can lead to friction, wear and, as a consequence, failure of elements on a rotating machine. Therefore, in order to design an effective bearing, it is important to know how the pressure is generated within the oil film and the magnitude of the load capacity transmitted from the collar to the bearing throughout the fluid. Thus, it is necessary to solve the Reynolds' Equation to obtain the distribution of pressure on the sections under Hydrodynamic Lubrication. Then several operational parameters can be obtained, such as, the total load capacity, lubricant fluid flow, position of the maximum pressure and so on.

This paper presents a software developed to apply the Hertz contact formulation to bearings with rolling elements, estimating the occurrence of surface fatigue failure in this kind of parts. Considering the wide range of designs in the automotive industry using this kind of bearings, a dedicated software, using a simple language, becomes a useful tool to reduce the design time, predicting in a satisfactory manner the failure of the bearing. The software developed shows a high level of accuracy, when compared to data provided by rolling bearing manufacturers.

In a large part of the mechanical elements used in machines and equipment, the preponderant failure mode is not that of fatigue of the element itself, but certainly the fatigue of a small point where the contact occurs. The prime example of this are the roller bearings, that they fail not by “breaking”, but by surface fatigue at contact points or on the tracks where there is contact between the rings and the rolling bodies. The optimization of the contact geometry, the material and the lubrication used can allow us to have larger admissible loads or lower system's costs where there is great influence of the contact fatigue. To make this optimization easier, a software was developed for a Windows platform, including the whole contact theory, the life calculations under surface fatigue and the lubricating fluid film thickness. In an interactive way, the user can change the data entrances such as material or geometry until an ideal solution is found for its problem.