Article Article
Digital Detercor Array for Offshore Pipeline Radiographic Testing

Digital radiography in the inspection of welded pipe to be applied under deep water offshore gas and oil pipelines with thick materials has been tested using digital detector array (DDA) or flat panel detector is considered the best solution to replace industrial films, as well as to increase probability of detection, due to increased sensitivity and reduction of the inspection cycle, time among other factors that contribute to the decision making for the change from conventional to digital technique. This paper describes some results of this new technique, digital radiography, comparing it to radiography by industrial films. In this study, four test specimens of longitudinal pipe joints welded, specially prepared with artificial discontinuities like cracks, lack of fusion, lack of penetration, porosities and slag inclusion of varying dimensions and in two different base metal wall thicknesses, were tested and a comparison of the techniques was made. This study was focused on the main part of requirements of ISO 10893-7 2011 specification standard. This technique is in continuous development and a new DDA will be supplied, as an increase in demand is perceived.

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