Introducing Advanced Non Destructive Tests to enhance the component evaluation task. The Threaded Components Phased Array In-service Inspection

摘要

The research for competitiveness in service market issues frequent calls for the maintenance process enhancement. This request can be satisfied thanks to technology evolution in non-destructive tests (NDT). It blazes new trail of development of tailored techniques for in-service components evaluation. As known, the threaded component integrity assessment has critical issues relative to: geometric complexity, accessibility, surface cleaning, result interpretation. These problems are present in superficial tests and volumetric test as well. In this paper, the development process for the phased array ultrasonic inspection of threaded components is described, with particular reference to bolts and fasteners. Making use of this technique appropriately, it is possible to realize a volumetric reconstruction of the threaded zone by means of acoustic images. In comparison to the conventional tests, it allows to reduce the inspection time thanks to the low number of scanning required and to increase the reliability making possible to resolve easily small in-service defects. Internalizing the capability to project inspection systems consents to increase their performance in a targeted way, whereas the experience with conventional methods has highlighted their limitations and issues. Following this strategy, it is possible to develop a technique considering specifically each step: the study of the component and its in-service flaws, the project of the phased array optimum transducer, the performance evaluation by means of computer simulations and the experimental validation on reference blocks.