PRODUCTS > IMPRESSED CURRENT SYSTEMS FOR VESSELS AND RIGS


FOR OFFSHORE VESSELS AND RIGS


SACOR Cathodic Protection System has the function to protect against corrosion the submerged parts of hulls of offshore vessels and rigs.

Working of the System
The system works based on the voltage level developed by the reference electrode. This signal is amplified and analyzed by the circuit generating a command for submitting rectifying bridge of more or less voltage for the anodes. The alarms are typically by over-voltage, under-voltage or over-current, and operate automatically in cutting the equipment working and/or activating local and remote signalizing of this event.

The equipment has voltage and current digital meters, installed on the front part for individual reading of every anode.

Most used anodes
The anodes used in system by impressed current for vessels and rigs are basically different from the galvanic anodes as they have an extremely low wearing and present, accordingly, longer life.

Material chemical characteristics
The anodes of Coated Titanium with Noble Oxides are very used, considering that they support higher current densities that the Plum/Antimonium/Silver anodes. And, in addition, the wear of these anodes is considered negligible.
Once the demand of current for the protection of submerged structures is high, it becomes more cost effective to use anodes of Plumb/Antimonium/Solver (Pb-Sb-Ag) or Coated Titanium with noble Oxides, which admit density of high current.

 



INERT ANODES RECOMMENDED FOR SEA WATER

 

Anode
Recommended Current
Density (A/m2)
Average Wear (Kg/A.Year)
Plumb/Antimonium/Silver (Pb-Sb-Ag)
50 a 1000
0,10
Coated Titanium with Noble Oxides
   Up to 600
Negligible (6 x 10-6)


The inert anodes, mounted on the vessel hull completely isolated from the steel, are manufactured with plates of Coated Titanium with Noble Oxides and encapsulate with epoxy resin. These anodes have stretched or rounded shape. In one of the Titanium faces one of the Noble Oxide layers is applied.

This coating has a life of around ten years, if there is no negligence in the assembly and maintenance or the part does not suffer any accident.

If the system is powered, the inert anode remains without incrustations of mollusks (oysters and shellfish), which produce acids that attack the coating layer.

The anodes of Coated Titanium with Noble Oxides do not need periodic maintenance, although it is recommended that every two years the plates conditions are observed as well as the wear in the oxide layer or signs of damage. It is also recommended to examine the encapsulate in epoxy resin, the fixing bolts, the electric wires and the dielectric protections around the anodes.