An uncommon blow out in a 24'' diameter, 7 mm thick API 5L X52 gas pipeline was due to fracture at the longitudinal double submerged arc weld (DSAW). Fatigue cracks were found to have initiated from a large embedded weld defect of lack of fusion, resulting from severe geometrical mismatch between inner and outer weld passes. Few large pressure cycles had been recorded during the 45 year service life of the pipeline. Fatigue tests were carried out to characterize propagation of fatigue cracks in weld metal, it was found that a large Paris exponent made the few large amplitude cycles most contributing to crack propagation. Crack growth path and striation patterns were studied. Fatigue growth was modelled by integrating experimental results and by extrapolating striation spacing in the fracture surface of the failed pipe. It was found that in the early life of the pipeline many more large pressure cycles than expected had occurred. Good correspondence between predicted and actual fatigue lives was in this way obtained.


    Access

    Access via TIB

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    Fatigue assessment of a double submerged arc welded gas pipeline


    Contributors:

    Published in:

    Publication date :

    2007


    Size :

    10 Seiten, 22 Quellen




    Type of media :

    Article (Journal)


    Type of material :

    Print


    Language :

    English




    Fatigue assessment of an electrical resistance welded oil pipeline

    Chapetti, M.D. / Otegui, J.L. / Motylicki, J. | Tema Archive | 2002


    Fatigue assessment of naval welded assemblies

    Erny, Carole / Thevenet, David / Cognard, Jean-Yves et al. | Tema Archive | 2010


    Fatigue assessment of welded aluminum ship details

    Tveiten, B°ard Wathne | TIBKAT | 1999


    Fatigue Assessment of Welded Aluminium Ship Details

    Tveiten, B. W. / Moan, T. | British Library Conference Proceedings | 1999


    Improving fatigue performance of welded joints of X65 pipeline steel by UIT

    Liu, Jinming / Chen, Tong / Zhang, Yufeng | Tema Archive | 2005