Corrosion inhibition of pipelines using high frequency electromagnetic signals

摘要

A method and associated apparatus for inhibiting corrosion in an elongate metal structure such as an oil well riser pipe is described. The method comprises applying a high-frequency electromagnetic signal to the structure, such that a voltage standing wave is established with a corrosion-inhibiting potential at the required region(s) of the structure. The apparatus may comprise: an annular core element 14 of magnetically conductive material e.g. ferrite, which extends around a pipe 10 and a signal generator producing an electrical output at the required frequency 16. The output from the signal generator 16 is applied to a coil (not shown) through which the magnetically conductive core element 14 extends as well as extending around the pipe 10. A node point may be established in the vicinity of the region of corrosion inhibition.