Cathelco, manufacturers of ICCP hull corrosion protection systems for ships and FPSOs, have launched a new generation of anodes which combine higher performance with a number of unique features to simplify installation.
The new C-Max anodes are available in a range from 50 amps to 300 amps covering the requirements of all types of vessels from small ferries and workboats to the largest VLCCs and container ships.
The anodes are available in linear or disc designs. In the case of the linear anodes, current is emitted from one or more tubular elements (tubes) produced from titanium with a coating of mixed metal oxide. These are mounted on an integral backing shield made from strong, but lightweight ABS plastic.
One of the most important features is that they are diver changeable, allowing them to be installed or replaced when the vessel is in drydock or at sea. They are also considerably lighter and easier to handle than existing anodes with the largest 300amp anode weighing only 14 kg.
Quicker and more accurate tightening is achieved through the use of self-snapping torque nuts. When the correct torque is achieved using an ordinary wrench, the top section of the nut snaps off leaving the lower section in intact for future use. No torque wrenches are required, greatly reducing the time and effort taken by divers when anodes are changed at sea. In addition, the nuts are yellow for increased visibility underwater.
The electrical connection is made through a single connecting rod which simplifies the task for the diver at installation and when the anode needs to be changed.
One of the first vessels to be fitted with C-Max anodes will be a bulk carrier (Hull GH405C) which is currently under construction at the Fujian Crown Ocean Shipbuilding yard in China.
As the vessel has a length of 190 metres, it will be equipped with forward and aft ICCP systems. The forward system will consist of two 50 amp disc anodes mounted port and starboard, whilst the more powerful aft system will have two 150 amp linear anodes with power supplied from modular control panels.
Another installation will shortly take place on an offshore wind turbine vessel (Hull H206) which is being built at the Huangpu Shipyard in China. Because of the vessel’s operating requirements it is being fitted with an aft only system using four 150 C-Max disc anodes. The anodes are recessed on the surface of the hull, avoiding the potential risk of damage on a vessel which frequently comes alongside.
The contracts have been won by Dickson General Appliance, Cathelco’s well established agent in China with offices in Hong Kong, Shanghai and Quingdao.
Cathelco are world leading manufacturers of impressed current cathodic protection (ICCP) systems for ships. The systems consist of an arrangement of anodes and reference electrodes which are connected to a control panel.
In operation, the reference electrodes measure the electrical potential at the hull/seawater interface and send a signal to the control panel which automatically raises or lowers the output to the anodes. In this way, the hull receives the optimum level of corrosion protection at all times.
Source: Cathelco, May 17, 2012