Metodologia para otimização de inspeção em tubos por radiografia digital direta

Abstract

The search for new methodologies and consequent improvement of existing inspection techniques are priorities in the process of increasing production efficiency in the industry. The objective of this study was to present a methodology for the correction of distortions in images made with Flat panel detectors of circumferential welds in tubes. The conditions that impose the distortions were determined and the geometries involved were mathematically described. To correct these problems, two algorithms constructed with the MATLAB program were proposed. Radiographic images of welded joints of steel tubes with different diameters were acquired using conventional radiography and Flat panel detectors. The defects were measured and compared in the conventional and digital images and in the images corrected by the algorithm, as well as image quality indicators, where an improvement of up to 17 times was observed in the SNRn relative to the higher signal uniformity after correction. The gray level deformations and the defects were corrected reaching 98% accuracy when compared to the standard. A 50% decrease in the number of images required for complete analysis of a 10-inch diameter tube was observed.