Transneft operates four marine terminals nowadays. Due to steady upgrade and ramping up of their throughput capacity, the issues of harbor infrastructure integrity maintenance and safe operation become of a vital importance. In particular, to enhance corrosion reliability of marine harbor and jetty facilities, the cathodic protection system retrofit is implemented. Earlier, for cathodic protection of harbor and jetty facilities sacrificial galvanic anodes were applied. Recently, new technical solutions were applied, and it requires validation of equipment selection. During the designing and searching of optimal technical solutions various difficulties occur: the locations of CP equipment in the offshore area, cable laying, etc. But one of the more urgent issues is the equipment selection for Company’s Register of General Types of Production, meant to provide maintenance reliability.
In order to confirm specifications of CP equipment of various domestic manufacturers, testing of impressed current anodes and long-term reference electrodes in field conditions of jetty facilities maintenance were conducted. Impressed current anodes of various materials were investigated, including widely applied Ti-based with conductive coating of catalytical metals (CM) or mixed metal oxides (MMO). Critical values of electrochemical parameters in field conditions were obtained. Various types of reference electrodes were investigated as a test samples: Ag/silver chloride, bimetallic, and zinc electrodes. In the course of testing parameters were evaluated such as open circuit potential stability and correlation of sample potential with cathodic polarization current.
The article presents testing results and preliminary conclusions on selection of equipment for cathodic protection system retrofit of marine facilities. Testing results will be applied for working out retrofit design solutions for cathodic protection system of Transneft’s harbor and jetty facilities; specifications for CP equipment to be included into the Register of General Types of Production; and updates into corporate regulatory documents in the field of marine facilities corrosion protection.
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