On the Optimization of Machined VSD Position for Repaired Pipes

Abstract

To be kept in use, pipelines with Volumetric Surface Defects (VSDs) must be evaluated and, if necessary, repaired. The first step in the repair process is machining the defect area. In all cases, the machined defect has a rectangular shape, with edges parallel/perpendicular to the pipe axis. We propose a novel approach: the VSD is scanned, the image is then processed using segmentation techniques, the VSD contour is detected, and finally, a family of rectangles with minimal area enclosing the VSD is defined. After that, a Finite Element Analysis is performed for each machined VSD, and an optimal case is selected.