INVESTIGADORES
OSELLA Ana Maria
artículos
Título:
Induction effects of 2D structures on buried pipelines
Autor/es:
OSELLA, A.,; MARTINELLI, PATRICIA; FAVETTO, A.; LÓPEZ, ERNESTO
Revista:
IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING
Editorial:
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
Referencias:
Lugar: New York; Año: 2001 vol. 40 p. 197 - 205
ISSN:
0196-2892
Resumen:
The implementation of cathodic protection systems is very complicated
since many factors can contribute for current flowing off the pipe. The
design requires the characterization of the parameters impacting the
corrosion process, such as soil resistivity, size of the pipe and quality of
the coating. In the present paper we study the effect of geomagnetic fields
on the pipe-induced currents considering it as an additional cause of
corrosion. A theoretical method previously implemented to model the currents
induced on pipes embedded in homogeneous soils, indicated a dependence
between the intensity of the currents and the electrical resistivity of the
soil and predicted that a drainage of current through the pipe would occur
at zones of shallow electrical discontinuities. Here, we present another
method for the calculation of the induced currents that lets to consider
also multilayered structures and lateral discontinuities in the earth
resistivity. Applying this method, we quantify the currents induced in
pipelines embedded in different bidimensional structures, in order to obtain
an estimation of the effects produced by the presence of such kind of
terrains.Then, we applied this method to model measured data. Field work was
performed along a 200 km-route of a pipeline-system. In this zone, the
pipe-to-soil potential was measured at different sites and a geophysical
study was made to determine the discontinuities in soil resistivities . We
obtained a correlation of the measured currents and soil resistivity that is
consistent with the theoretical predictions. This fact strongly suggests
that in zones of deep high resistive contrast, the current circulating in
the pipes increases, being the consequent risk for the coating and the
cathodic protection adjusting, not only dependent on the resistivity of the
ground-bed but also on this deep structure.