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Cranes and rigging equipment are important machines in industrial activities, construction, port operations and in many sectors that demand the lifting of high loads in a safe, controlled and efficient way. And the design of these equipment, in turn, requires the use of machine elements, mechanisms, and structures that are widely used in engineering, such as wire ropes, gears, pulleys, bolted connections, structural profiles, etc. In this work, a rotary wall crane was built in a virtual environment. The design was based mainly on the ABNT NBR 8400 standard. The software used for 3D modeling was Autodesk Inventor® and the main structure of the equipment was analyzed, according to its functionality, using numerical simulations based on the finite element method. Firstly, the structure of the crane, consisting of L and U structural profiles, bolted joints, structural reinforcements and other connections, was analyzed separately.

The union of parts by using bolts is one of the most used, which combines versatility and low cost, and the failure of a single bolt can cause failure of the entire structure or machine. Several factors influence the effectiveness of these bolted joints, including the material of the washer. During the process of applying torque to the bolted joint, an elastic deformation occurs in the bolt and a plastic deformation in the washer while applying the external force. This plastic deformation which occurs in the washer causes a reduction of the elastic deformation of the bolt and, consequently, of the assembly torque, and depending on the values of external loading and deformation of the washer occurs the separation of the pieces of the joint, causing overload in the bolt and a reduction in your fatigue life. The use of numerical simulation using the finite element method makes it possible to change the model variables, such as the geometry and materials of the components.

The development of the technology of rolling bearings, such as cylindrical or thrust bearings has as one of its objectives constitute a set of mechanical components that combine mechanical strength and stiffness, designed to support the loads, speeds and life specified for a particular application. This project aims to discuss the application of the finite element method in the analysis of fatigue failure in rolling bearings, evaluating the influence of some construction and operational parameters in the stress distribution, such as geometry of contact surfaces, applied load, rotation, and properties of materials in contact. Specifically, we investigated the relationship between the stress caused by cyclic loading in fatigue life of these bearings. The analysis of the life of rolling bearings was performed using the commercial software ANSYS, based on the finite element method in a virtual environment.

The stress concentration appears in components that have abrupt changes in its geometry or discontinuities such as holes, etc. Because of the presence of these discontinuities occurs a increasing of the stress value. There are several studies to estimate the increase of stress in metallic materials, however, a specific literature for calculating the stress concentration in composite materials is still low, even with the increase of its use in replacement of components made of metallic materials in recent years, particularly in the aerospace and automotive industries. This study was elaborates a computer simulation program of a component with a cylindrical holy and used the finite element method for calculating the stress concentrations using the commercial software ANSYS 10.0. This simulation has the objective to analyze the structural behavior of the component.

The use of composite materials has increased in the recent decades, mainly in the aeronautics and automotives industries. In the present study is elaborated a computational simulation program of the bending test using the finite elements method, in the commercial software ANSYS. This simulation has the objective of analyze the mechanical behavior in bending of two composites with polymeric matrix reinforced with carbon fibers. Also are realized bending tests of the 3 points to obtain the resistances of the materials. Data from simulation and tests are used to make a comparison between two failures criteria, Tsai-Wu and Hashin criterion.

Projects of machines make in a conventional way involving transmission through systems of gears consumes a long time because of the large volume the graphs and tables to be consulted, as well as the difficult equations to be solved. In this work we will present a proposal whose purpose is auxiliary the designer in the dimensioning of the mechanical elements and reduce the time spends during the development of projects the spur gears. This reduce is reached through the elaboration the specialist program for automation the analytic calculations of these transmission elements, using the computer to execute the most tiresome and repetitive tasks, and therefore more susceptible the errors, in a programming language guided to objects and events, DELPHI. This specialist program also allows the construction a parametric file in function of the independents variables that make a simulation of shipments in spur gears, applying the finite elements method.

About 99% of mechanical failures are consequence of the phenomena of fatigue, which consists on the progressive weakening of the resistant section of a mechanical component due to the growing of cracks caused by fluctuating loadings. A broad diversity of factors influences the fatigue life of a mechanical component, like the surface finishing, scale factors, among others, but none is as significantly as the presence of geometric severities. Stress concentrators are places where fatigue cracks have a greater probability to occur, and so on, the intuit of this work is to develop a consistent and trustfully methodology to determine the theoretical stress concentration factor of mechanical components.