TAQA’s North Cormorant platform is an eight-legged steel jacket structure, installed in 1981 with approximately 2800 sacrificial anodes which had a design life of 30 years. Heavy anode depletion was formally noted in subsea reports since 2007. In 2014, the jacket structure was found to have potential readings of -659mV at depths below -133m, which is outwith recommended guideline limit of -800mV vs. Ag/AgCl reference electrode. To ensure structural integrity to end of field life a new protection system was required to improve the jacket CP. Studies concluded that retrofit sacrificial anodes would not provide the required repolarisation current and the required physical size was impractical therefore a bespoke impressed current system was selected, comprising;
PDi were engaged to provide engineering and project management support for the cathodic protection upgrade project consisting of the following elements:
UKCS, Northern North Sea
November 2014 (11 months)
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