船舶外加电流阴极保护iccp.pdf

ICCP Hull Corrosion Protection Systems Pitting corrosion around exhaust discharge.General corrosion on hull plate. Corrosion around bow thruster.Corrosion ‘blisters’ on hull plate. Background image – Corrosion on propeller shaft bracket arm The Problem of Corrosion Corrosion takes many forms in the marine environment. It can be seen as pitting on hull plates; in the disintegration of weld seams; around bow thrusters and on the surfaces of rudders and other vital components. A well designed ICCP system can eliminate these problems, safeguarding the structural integrity of the vessel and significantly reducing maintenance costs throughout its operational life. By installing a Cathelco system you can have the advantage of world leading ICCP technology combined with the expertise which goes with wide understanding of corrosion problems and the most effective way of solving them. Cathelco C-Shield impressed current cathodic protection (ICCP) systems have now been fitted to more than 10,000 vessels around the world, establishing a record of effective performance and reliability on ships of every type:-  Cruise Ships  Container Vessels  VLCCs  Ferries  FPSOs  Ice Class Vessels Cathelco have recently introduced C-Max anodes, a new range of linear and disc anodes which combine high performance with a number of features to simplify installation. The most important feature is that they are diver changeable enabling them to be replaced without drydocking. The linear anodes are exceptionally lightweight and can be easily carried by one man. They are fitted using self-snapping torque nuts to speed up installation. Other developments have included the introduction of ICCP systems which are specifically designed to protect bow and stern thruster tunnels. Alongside this has gone the design of more sophisticated shaft earthing systems and rudder bonding equipment to provide reliable protection for propulsion and steering systems on today’s vessels. In the case of smaller vessels, the Minitek and Alutek systems are compactly designed to protect steel and aluminium hulls, respectively. Cathelco serves customers globally through a well established network of over 40 agents who can provide on-the-spot access to technical advice and commercial support. Following a series of takeovers, Cathelco incorporates the following product ranges:-  Cathelco  Corrintec  Jotun  Morgan Berkeley  Wilson Taylor  F.A.Hughes Cathelco ICCP systems for vessels of every type RUDDER BONDING REFERENCE ELECTRODE C-MAX LINEAR ANODE REMOTE MONITORING UNIT SHAFT EARTHING ASSEMBLY CONTROL PANEL 50-75A & 100A Linear Anodes Designed with a single current emitting element either 25 or 32mm diameter, these anodes are exceptionally lightweight and versatile. Size: 740mm x 400mm Weight: 7 Kg 125-200A Linear Anodes Produced with two 32mm diameter elements these high performance anodes are easy to install. Size: 740mm x 400mm Weight: 7 Kg 225-300A Linear Anodes Designed for the largest vessels, these anodes have three elements to produce outputs of up to 300A. Size: 1380mm x 400mm Weight: 14kg Impressed Current Cathodic Protection Systems CONTROL PANEL C-MAX DISC ANODE REFERENCE ELECTRODE Disc Anodes Generally used on ‘forward’ systems, these are produced in two sizes:- 50-100A. Size 370mm diameter. Weight: 4kg 125-175A. Size 526mm diameter. Weight 9kg Reference Electrodes Cathelco zinc reference electrodes are fully diver changeable. They are also available with silver/silver chloride elements. Size: 125mm diameter Weight: 9kg Most operators recognise the need to combine modern hull coatings with a purpose designed impressed current cathodic protection system. The C-Shield system suppresses corrosion on the wetted surface of the hull using an arrangement of hull mounted anodes and reference electrodes connected to a control panel. This neutralises ‘corrosion cells’ and eliminates problems that arise through dissimilar metals and the proximity of components such as propellers. Impressed Current Cathodic Protection Systems How ICCP systems operate The most important feature of an ICCP system is that it automatically detects the electrical potential at the hull/seawater interface and raises or lowers the output to the anodes accordingly. In this way, the ship receives the optimum level of protection at all times. The electrical ‘potential’ is monitored by reference electrodes which are fitted port and starboard between the anodes where the lowest ‘potential’ is likely to occur. This reading is fed back to the control panel which automatically adjusts the anode output. On larger installations, above 350 amps, thyristor control panels are generally used which provide a low voltage controlled and rectified d.c. power source to the anodes. On smaller installations, Cathelco provide modular control panels with computerised electronics with the advantages of space and weight savings. The new generation of C-Max anodes are available in linear and disc designs w。