Search Results

The study of rotative machines occupies an outstanding position in the context of machines and structures in view of significant amount of typical phenomena in the operation of those equipments. The existence of a rotative component leaning by bearings and transmitting power and torque creates a family of problems that are found in the most several machines. Therefore, in the study of the dynamic behavior of those systems, it is necessary to be determined the interaction among all the components that affect in a significant way the dynamic behavior of the system. It is proposed, this way, to determine the dynamic behavior of Rotor-Bearing-Coupling system using a Multiobjective Genetic Algorithm coupled with Surface Response Method. The Rotor-Bearing-Coupling system has the support structure or foundation practically rigid, in way to allow the analysis of the transverse or flexional vibrations of the system.

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.

The purpose of this software we developed was to make na analyses of the quality of mechanical components using reliability calculus. The computer program is a powerful tool, for it deals with failure tests, commonly used in practice to obtain the mean life, which is a fundamental parameter in advanced techniques of maintenance. Moreover, the work intends to make accessible concepts related to the reliability of systems and components in Mechanic Engineering, making possible a better understanding and familiarity. The subject is of great application in the great industries and projects with high levels of precision and security. What will determine the satisfaction of the customer after a component, and in consequence, its retention is the performance of its technique characteristics in the period of its life.

The productivity of a system can be measured by a combination of parameters as the reliability, mantenability, availability and dependability, which are influenced by the time of functioning and facilities in the repair of the equipment. This work is resulted of the development of a software in the Department of Mechanical Design of the Faculty of Mechanical Engineering of the State University of Campinas. This software carries out, basically, Analyses of Failure, Maintenance and Availability. The Analyses of Availability and Dependability as well as a previous analysis of the Economic Viability have been the subjects treated in this work.

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.