Flexible risers are flexible pipes used to bring oil from oil wells deep underwater to the surface, where it can be processed by Floating Production, Storage and Offloading (FPSO) installations. Flexible risers consist of a number of layers of steel and polymer that have a complex structure and some layers are shielded by others, making non-destructive testing particularly difficult. This paper presents some experimental radiography of a sample flexible riser. Both single-wall and double-wall techniques were used with X-rays and gamma rays with both computed radiography imaging plates and an amorphous silicon flat-panel detector. The layer of the riser that is of particular interest is the pressure armour, which is the layer designed to withstand the internal pressure. It is a layer that is particularly difficult to inspect, as it is shielded by a metallic layer on both sides. The resulting images were used to develop an image processing technique designed to detect separations in the pressure armour, which is also presented here. The technique is based on the use of the Hough transform to detect nonstructural lines in the image. This technique has been tested on a defect simulated by image processing and an artificial defect introduced to the flexible riser sample. The technique was found to be successful in detecting the artificial defect in a set of images, with only 4 % of misclassification, which were all false positive results.


    Zugriff

    Zugriff über TIB

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Automated radiographic inspection of flexible risers. A feasibility study


    Weitere Titelangaben:

    Automatische radiographische Prüfung flexibler Steigeleitungen. Eine Machbarkeitsstudie


    Beteiligte:
    Mallett, R. (Autor:in) / Blakeley, B. (Autor:in) / Balachandran, W. (Autor:in)

    Erschienen in:

    Insight ; 47 , 12 ; 752-755


    Erscheinungsdatum :

    2005


    Format / Umfang :

    4 Seiten, 6 Bilder, 2 Tabellen, 5 Quellen




    Medientyp :

    Aufsatz (Zeitschrift)


    Format :

    Print


    Sprache :

    Englisch




    Automated Radiographic Inspection of Flexible Risers: A Feasibility Study

    Mallett, R. / Blakeley, B. / Balachandran, W. et al. | British Library Conference Proceedings | 2005


    Extreme Responses of Flexible Risers

    Trim, A. D. | British Library Online Contents | 1992


    Extreme responses of flexible risers

    Trim, A.D. | Tema Archiv | 1992


    Bend Stiffeners for Flexible Risers

    Lane, M. / McNamara, J. F. / Gibson, R. et al. | British Library Conference Proceedings | 1995


    Radiographic Inspection

    SAE Technical Papers | 1999