ILI (in-line inspection) of the TAPS (trans Alaska pipeline system) using high resolution metal loss and caliper tools indicated 77 locations with suspected minor MDFs (mechanical damage features). The tools used are able to detect the presence of a suspected feature, and measure indented dimensions, but are insufficient to detect the presence of cracks or gouges needed to reliably assess feature severity based solely on the ILI data. Excavations of 42 sites deemed most severe provided important field data characterizing residual deformation dimensions, revealed the occurrence of generally surficial gouges or cracks, and allowed a reliable field assessment of defect severity. Upon completion of the excavations, 35 possible MDF locations remained unexcavated. An engineering evaluation was undertaken to assess whether or not the remaining MDFs pose a threat that is significant enough to warrant excavation. Multiple assessment methods were utilized including deterministic, probabilistic, and risk assessment methods. A deterministic mechanics model was developed to estimate the safe operating life of the pipeline at each of the remaining uninvestigated locations considering the characteristics of previously observed damage, the perceived severity of uninvestigated damage, material properties of the pipe, and the fatigue environment resulting from expected modes of pipeline operation. The results strongly suggested that 33 of 35 damage features were extremely minor, with remaining life well in excess of the remaining project life cycle. None of these features were judged to threaten the immediate integrity of the line, and are unlikely to do so in the foreseeable operating life of the facility. The results also were found to support the outcome of the operator's risk-based evaluation process.


    Zugriff

    Zugriff über TIB

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Deterministic assessment of minor mechanical damage on pipelines


    Weitere Titelangaben:

    Die deterministische Bewertung kleiner mechanischer Schäden an Rohrfernleitungen


    Beteiligte:
    Rosenfeld, M.J. (Autor:in) / Beckett, Alan (Autor:in) / Neogi, Bhaskar (Autor:in) / Baskurt, U.J. (Autor:in) / Johnson, Eiden (Autor:in)


    Erscheinungsdatum :

    2007


    Format / Umfang :

    12 Seiten, 16 Quellen



    Medientyp :

    Aufsatz (Konferenz)


    Format :

    Print


    Sprache :

    Englisch




    Assessing mechanical damage in offshore pipelines - Two case studies

    MacDonald, K.A. / Cosham, A. / Alexander, C.R. et al. | Tema Archiv | 2007


    Anchoring pipelines prevents damage

    Odusch, J.M. | Tema Archiv | 1980



    Seismic damage to pipelines in the framework of Na-Tech risk assessment

    Lanzano, Giovanni / Santucci de Magistris, Filippo / Fabbrocino, Giovanni et al. | Tema Archiv | 2015


    Safety assessment of offshore pipelines anchor damage by means of simulation method

    Gucma, L. / Zalewski, P. / Wessex Institute of Technology | British Library Conference Proceedings | 2001