Aplicação da metodologia 8D para resolução de defeitos em componentes para pás eólicas: um estudo de caso sobre a fabricação de SPAR CAPS

Abstract

Nowadays, society experiences the tendency to expand the application of renewable resources energy, instead of using fossil fuels, in order to reduce environmental impacts. In Brazil, the wind energy currently represents 11.46% of the energy matrix. Given the growth of wind power plants, improvements in the manufacturing process of the components that make up wind blades are increasingly required; improvements which should consider the most efficient aerodynamic format of the blades and which generally consist of procedural changes implemented in industries in a short period of time. The detection of defects in the manufacture of wind components can often be harmed by the lack of data from problems that occurred previously. Therefore, it is necessary to develop research that deals with case studies related to this subject. In view of this, the present work aims to analyze aerated defects in spar caps, one of the most important structural components of a wind blade, through the application of the 8D management. The objective was to determine the causes of the defects, as well as propose a set of effective actions capable of containing the occurrence of these. Furthermore, the intention was to review the production process of spar caps, to understand and evaluate the relevant parameters. Visual, dimensional and, in some cases, microstructural analyses were performed, as well as pull-off tests and periodic monitoring of temperature and humidity of the pieces and environment. From the analysis of the results, the 8D management proved to be a very effective tool, and its use was successful to solve the problems detected in the process of manufacturing spar caps. The action plan elaborated was very effective. After the implementation, zero-defect parts were produced and approved by the visual and ultrasonic inspection criteria. The main actions to solve the problem were the change of the infusion plan, which allowed the delay in the resin flow in certain regions, and the study of the heating curves along the entire length of the mold. The pull-off tests and microstructural analyses provided the approval of 14 of the 21 spar caps affected by the defects, which represent a saving of approximately R$ 1,800,000.00 in materials, ignoring secondary costs inherent to production.