Three cases of failure in two 30-40 year old pipelines are analyzed. The first case arose as a consequence of an unsafe working practice on the line. A pressure burst was generated, leading to a through axial crack corresponding to a pre-existing manufacturing defect. The second accident occurred during normal operation, but was a consequence of the first accident, which weakened the pipe, causing the subcritical growth of pre-existing defects related to the high carbon equivalent content of the pipe steel. The third accident occurred in another pipeline: external corrosion, related to incomplete tar lining of the pipe near a welding seam, caused oil leakage. To clarify the fracture conditions for the first two accidents, the collapse pressure has been evaluated employing the R6 Structural Integrity Assessment Method. The results verify quantitatively previously reported explanations, obtained by flow dynamics analysis and macroscopic and microscopic fracture observations.


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Structural collapse calculations of old pipelines


    Contributors:
    Doglione, R. (author) / Firrao, D. (author)

    Published in:

    Publication date :

    1998


    Size :

    8 Seiten, 19 Quellen




    Type of media :

    Article (Journal)


    Type of material :

    Print


    Language :

    English




    Asymmetric collapse of offshore pipelines under external pressure

    Gong, Shun-feng / Ni, Xing-yue / Bao, Sheng et al. | Taylor & Francis Verlag | 2013



    Local collapse of gas pipelines under sleeve repairs

    Otegui, J.L. / Urquiza, S. / Rivas, A. et al. | Tema Archive | 2000


    Numerical tool to model collapse of polymeric liners in pipelines

    Rueda, Federico / Otegui, Jose Luis / Frontini, Patricia | Tema Archive | 2012


    Plastic collapse analysis of pipelines containing surface-braking circumferential defects

    Wang, Y.Y. / Wilkowski, G.M. / Horsley, D.J. | Tema Archive | 2000