Simulação do processo de rosqueamento interno com macho de corte utilizando o método dos elementos finitos

Abstract

Internal thread tapping is a very quick, but complex, manufacturing process. This is due, mainly, for two reasons: the difficulty of synchronizing the rotational movement of the tool with its advance and the complex geometry of a cutting tap. This operation, therefore, is still little studied by the scientific community and not all of its peculiarities are known. In recent years, researchers have used numerical methods, especially the finite element method (FEM), to try to study machining processes through mathematical models. Thus, this work aims to propose a three-dimensional model of the tapping process to study the operation and the particularities of your tool, using the commercial software AdvantEdge to solve this model through the FEM. To study this type of threading, a three-dimensional model was proposed where the tool was sectioned after the second row of its cylindrical threads and cut only the first thread fillet in the hole, at which time the forces and torque develop in their maximum values. With this simplified model, tests were made to study the synchronization error, varying the type of tool coating, the type of tool radial relief used, the number of flutes in the tool and its chamfer angle. The simulation results showed that it is possible to study the internal threading process through the proposed three-dimensional model. Torque and thrust forces decrease as the number of tool flutes increases. These two variables increase when a coating is applied to the tool. They are also very sensitive to a change in feed rate around the tool, and the farther from the ideal (1 mm/revolution) the greater the changes they undergo. The type of radial relief has a great impact on the force in the feed direction, and the flatted land relief type presented the lowest force. The chamfer angle has a great influence on the process torque, increasing it as this angle decreases.