Chevron tank reference electrodes

New reference electrodes installed in offshore Gulf of Mexico float cells

Deepwater supervised the installation of reference cells and commissioned the impressed current cathodic protection (ICCP) systems for two Chevron Tahiti float cell vessels. Deepwater concluded during earlier testing that the reference electrodes were malfunctioning.

During commissioning, the reference electrodes were replaced with HP-1Z-HT high-temperature zinc potential control reference electrodes. The two float cells, along with one oil treater and their CP systems were also visually inspected by Deepwater personnel.

All anodes were cleaned and visually inspected. One anode had separated from the flange in one of the float cells, so Deepwater replaced the anode and seal in the existing flange assembly. A cable tray was temporarily moved to ensure proper installation of the repaired anode, and isolation checks verified the reference cells and anodes were not contacting the tank structure. The work was performed during a routine tank cleanout to minimize downtime.

Commissioning was performed by Deepwater representatives and a characterization curve was established for one of the float vessels for future reference. Reference cells and anodes were operational when last checked and transformer rectifier (TR) measurements are collected monthly by maintenance crews to verify that the TR is operational and providing adequate cathodic protection.