Cathodic Protection Electrolytic Antifouling

Cathodic Protection Electrolytic Antifouling

CATHWELL AS Cathodic Protection Electrolytic Antifouling Business concept Cathwell specialises in design, manufacture and supply of systems for cathodic protection and electrolytic antifouling. Origin Cathwell AS, previously known as Active Cathodic Protection, was founded in 2003. In 2011 the company went through a revitalisation process changing its name to Cathwell AS. Cathwell AS acquired a cathodic protection segment from the paint company Jotun in 2003, when Jotun decided to phase out this business. The English company Cathelco was involved in the acquisition, but personnel from former Jotun Cathodic Protection remained in Cathwell/Norway. Prior to Jotun Cathodic Protection the company name was Skarpenord Corrosion. Markets Cathwell covers a wide range of applications including vessels, subsea structures, mobile rigs & FPSO s, wind turbines and various onshore structures. International network Cathwell s main office is in Norway. The sales and service agents are represented in: Norway: Head office Denmark: Sales agent Poland: Service agent Greece: Sales agent France: Sales agent China, Hong Kong: Sales agent China, Shanghai: Sales & service agent Singapore: Sales & service agent

ELECTROLYTIC ANTIFOULING By impressing DC current through the antifouling anodes, dissolved ions will flow through the cooling system preventing biological marine fouling. Anode rods in sea chests The anode rods (copper and aluminium or iron) are preferentially installed in the sea chests to treat the seawater before entering the piping system. Anode rods in strainers The antifouling anodes may be installed in the strainers, either in addition to or as an alternative to location in sea chests. Box coolers Copper rod anodes are located below the box cooler tubes to provide an even distribution of copper ions to the box cooler. The system control unit is continuously maintaining the correct current output in order to obtain sufficient amount of copper ions in the seawater surrounding the box cooler. Antifouling anodes Anode material: Cu, Fe and Al Anode diameter: Ø60-130 mm Anode length: 0,2 to 2 m Cofferdams for flange mounting or welding Control unit 15 V / 3 A per channel 230 V, 50/60 Hz, 1 phase mains input THD (Total Harmonic Distortion) less than 5 % Individual channel adjustment and readings

IMPRESSED CURRENT (ICCP) Advantages of ICCP vs sacrificial anodes Fuel cost saving achieved by a smooth hull surface (no drag as by sacrificial anodes) Longer operational life time than sacrificial anodes (no need for replacement every dry-docking) Unlimited protection capacity (accepts higher coating breakdown than sacrificial anodes) Continously monitoring and automatic adjustment of the protection level As opposed to most other ICCP systems the anodes and reference electrodes from Cathwell can be replaced while vessel is floating, by use of divers. ADS-1 anode with cofferdam 50-60 A output. Mechanical re-inforced (solid Ti base). MMO coated with neoprene encapsualtion. Fully recessed and diver changeable. Prepared for void spaces and water ballast tanks. ADS-2 anode with cofferdam 75-90 A output. MMO/Ti anode with neoprene encapsulation. Fully recessed and diver changeable. Prepared for void space and water ballast tanks. ADS-3 anode 100-120 A output. MMO/Ti anode with neoprene encapsulation. Fully recessed and diver changeable. Prepared for installation in void space and water ballast tanks.

Current from the control unit is flowing from the anodes, through the seawater to the hull providing corrosion protection. The level of protection is controlled by a potential signal measured by the reference electrodes. RSH anode and cofferdam Zinc reference electrode with neoprene encapsulation. +/- 30 mv accuracy. Fully recessed and diver changeable. MAG 24 control unit Compact and lightweighted with high regulation accuracy. Switch-mode technology, module based with hot plugability. Capacity 27 V / 110-440 A. Propeller shaft grounding Grounding device either with solid silver slip ring or silver band around the propeller shaft. Double contact brushes and monitoring device are standard.

SACRIFICIAL ANODES Sacrificial anodes on ship hulls and ballast/cargo tanks protects steel and preserves coatings. A great variety of welded and bolted ballast tank anodes with different fastening devices are available. Customised anode types and shapes can be produced on request.

STANDARD FLUSH ANODES ALUMINIUM AND ZINC Most anode types and sizes can be supplied. Customized anode are available upon request. Standard flush anodes are for welding. Bolt holes in steel inserts to be provided upon request. Doubler plates for flush anodes are available in different sizes. Anode type Standard ALUMINIUM flush anodes Weight (kg) Gross Net Dimensions (mm) L1 L2 H W 2-AL 0.2 0.15 90 164 23 46 4-AL 0.4 0.3 120 210 28 62 A-10 1.0 0.8 210 255 27 80 15-AL 1.5 1.2 215 300 30 95 25-AL 2.5 2.0 270 350 32 120 A-25 2.5 2.1 305 365 40 102 A-33 3.3 3.0 190 250 84 90 43-AL 4.3 3.4 370 450 32 120 A-50 5.0 4.3 445 505 40 125 A-54 5.4 5.0 230 290 92 100 60-AL 6.0 5.2 570 700 43 110 A-80 8.0 7.0 640 700 43 125 80-AL 8.0 7.5 350 450 62 150 90-AL 9.0 7.8 930 1060 40 110 A-116 11.6 10.0 800 880 50 125 114-AL 11.4 10.6 600 700 79 120 A-130 13.0 11.2 890 960 47 125 A-180 18.0 15.5 1210 1290 47 125 170-AL 17.0 15.8 960 1060 73 120 A-220 22.0 19.8 1100 1180 85 105 350-AL 35.0 31.6 1920 2000 71 120 399-AL 39.9 33.3 2500 2580 60 185 Anode type Geometric variations between the different anodes types may occur. Standard ZINC flush anodes Weight (kg) Gross Net Dimensions (mm) L1 L2 H W 2-Z 0.22 0.17 98 140 13 33 5-Z 0.5 0.45 120 164 23 46 10-Z 1.0 0.9 140 210 28 62 Z-18 1.8 1.7 160 205 30 80 20-Z 2.0 1.9 165 210 30 90 Z-30 3.0 2.8 250 300 25 80 35-Z 3.5 3.2 220 300 30 96 Z-51 5.1 4.6 300 350 32 80 55-Z 5.5 5.1 260 350 33 113 Z-85 8.5 8.1 400 450 35 97 102-Z 10.2 9.3 350 450 33 150 Z-108 10.8 10.2 395 455 43 125 155-Z 15.5 14.7 590 700 45 116 Z-160 16.0 15.1 550 620 43 127 Z-200 20.0 19.3 500 525 50 128 Z-220 22.0 20.6 680 760 45 127 235-Z 23.5 21.5 960 1060 40 120 Z-270 27.0 25.3 800 880 50 125 Aluminium anodes Capacity: 2651 Ah/kg Consumption rate: 3.3 kg/ayear Specific gravity: 2.78 kg/dm 3 Closed circuit potential: -1100 mv vs Ag/AgCl/seawater Zinc anodes Capacity: 780 Ah/kg Consumption rate: 11.2 kg/ayear Specific gravity: 7,13 kg/dm 3 Closed circuit potential: -1030 mv vs Ag/AgCl/seawater

Cathwell AS, PO Box 68, Clarksgate 5, NO-3970 Langesund, Norway Tel. +47 35 96 78 50, fax. +47 35 96 78 60, contact@cathwell.com