Joliet TLP

19 RetroPods™ with RetroClamps™ installed on tension leg well platform in the Gulf of Mexico

Deepwater Corrosion Services was contracted to extend the life of the cathodic protection (CP) system for a tension leg well platform in approximately 1,767 feet of seawater in the Green Canyon area of the Gulf of Mexico. A total of 19 RetroPods™ with RetroClamps™ were installed around the base of the TLWP foundation template.

Installation by ROV

Installation included 4 jumpers to establish continuity between the foundation template and the drilling template, along with an optional installation of 4 more jumpers between the foundation template and the well pods to guarantee electrical continuity. Pre-retrofit and post-retrofit CP readings using ROV-mounted contact CP probes were taken.

ROVs helped guide each RetroPod™ into its designated position and installed 18” RetroClamps onto the structure. The four jumpers were each installed by lowering the larger clamp, which was attached to the smaller clamp with a strain-relief rope, to a depth of 1,700 feet. The ROV mounted the smaller RetroClamp™ first, released the larger clamp from the hoist and installed the clamp on its designated member. In addition to the first four jumpers, four more were added between the foundation template and the well pods to ensure electrical continuity. A post-retrofit CP survey of the structures showed that all readings were above the protection threshold, and the estimated life of the CP system had been increased by ten years.