Projeto de um equipamento para a avaliação da interação entre porca, parafuso e arruela em juntas aparafusadas

Abstract

The objective of this work was to design of an equipment for the evaluation of the interaction etween bolt, nut and washer in bolted joints. The design of the equipment was based on the ISO 16047: 2005 standard. The demand for knowledge of the torque x force ratio of bolted joints is increasingly required in industrial applications and for this purpose tests must be carried out to determine the clamping characteristics of the elements in use. The main characteristics of the screws that can be measured by the tests of this machine are: torque coefficient (K), total friction coefficient, (utot), thread friction coefficient, (uth) and friction coefficient in the face of the head of the screw / nut, (μ𝑏). Different diameters, types, materials and grades of bolts are the initial the information needed to design the torque-tension machine. Therefore, the screws of 1/2 " to 1 1/2" were defined, then, from these values, the design limits were calculated. The assembly concept was developed and the commercial components specified. The designed machine is within the parameters required by standard and meets the defined specifications. In addition, it was previously identified possibilities of improvement with the deepening of the study of some aspects of the machine. The designed machine, therefore, is robust with well-defined features and easy to implement improvements.