| Titre | Assessing pipeline vulnerability to telluric currents |
| Auteur | Boteler, D H |
| Source | Proceedings of CORROSION 2007; 2007 p. 1-16; 1 CD-ROM |
| Année | 2007 |
| Séries alt. | Secteur des sciences de la Terre, Contribution externe 20100350 |
| Réunion | CORROSION 2007; Nashville; US; mars 11-15, 2007 |
| Document | livre |
| Lang. | anglais |
| Media | CD-ROM; numérique |
| Sujets | interpretations telluriques; levés telluriques; champ tellurique; pipelines; établissement de modèles; géophysique; géologie de l'ingénieur |
| Illustrations | graphs |
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| Programme | Targeted Hazard Assessments in Northern Canada, Géoscience pour la sécurité publique |
| Résumé | (disponible en anglais seulement)
Telluric currents produce variations in pipe-to-soil potential (PSP) that take the pipeline outside the voltage range for cathodic protection and interfere with
potential surveys. The size of the PSP variation depends on a variety of factors related both to the natural environment and the characteristics of the pipeline itself. This paper presents a methodology for assessing how different pipeline features
influence the vulnerability of the pipeline to telluric effects. Derivation of the distributed-source transmission line (DSTL) equations for induction in a pipeline show that the critical parameters are the series impedance of the pipeline steel and
the parallel conductance to ground through the pipeline coating. Large PSP variations occur where there is a disruption in the flow of telluric currents along the pipeline, such as happens at the end of the pipeline, at flanges, at bends, and changes
in pipeline characteristics. A series of plots are presented showing the dependence of PSP variations on coating conductance, changes in series impedance and bends in the pipeline. Also examined are how the PSP variations are modified when
overlapping effects occur. Finally, the paper considers the effect of various mitigation strategies and presents model results of the reduction in PSP variations that can be achieved. |
| GEOSCAN ID | 287394 |
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