Cathodic Protection ∙ Electrolytic Antifouling

CATHWELL ASCathodic Protection ∙ Electrolytic Antifouling

Business conceptCathwell AS is specialized in providing solutions for cathodic protection and water treatment for maritime, offshore and onshore markets.

OriginCathwell 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.

MarketsCathwell covers a wide range of applications including vessels, subsea structures, mobile rigs & FPSO’s, wind turbines and various onshore structures.

International networkCathwell’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

• USA: Sales & service agent

www.cathwell.com - www.cathwell.no

ELECTROLYTIC ANTIFOULING

Anode rods in sea chestsThe 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 strainersThe antifouling anodes may be installed in the strainers, either in addition to or as an alternative to location in sea chests.

Box coolersCopper 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.


By impressing DC current through the antifouling anodes,dissolved ions will flow through the cooling system preventing biological marine fouling.

Antifouling anodes• Anode material: Cu, Fe and Al• Anode diameter: ø60-150 mm• Anode length: 0.1 to 2 m• Cofferdams for flange mounting or welding

CathFlow® 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• Computerized operation, with automatic logging and remote operation


Advantages of ICCP vs sacrificial anodes

• Fuel cost saving achieved by a smooth hull surface (no drag as by sacrificial anodes)

• Longer operational lifetime than sacrificial anodes (no need for replacement every dry-docking)

• Unlimited protection capacity (accepts higher coating breakdown than sacrificial anodes) • Continuously monitoring and automatic adjustment of the protection level

IMPRESSED CURRENT (ICCP)

ADS-1 anode with cofferdam50-60 A output. Mechanical reinforced (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 cofferdam75-90 A output. MMO/Ti anode with neoprene encapsulation. Fully recessed and diver changeable.Prepared for void space and water ballast tanks.

ADS-3 anode100-120 A output. MMO/Ti anode with neoprene encapsulation. Fully recessed and diver changeable.Prepared for installation in void space and water ballast tanks.

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.


RSH anode and cofferdamZinc reference electrode withneoprene encapsulation.+/- 30 mV accuracy. Fullyrecessed and diver changeable.

CathSense® control unitModule based, compact and lightweighted with high regulation accuracy and flexibility. Computerized dashboard based operation, with automatic logging and remote operation. Capacity 27 V / 120-720 A.

Propeller shaft groundingGrounding device either with solid silver slip ring or silver band around the propeller shaft. Double contact brushes and monitoring device are standard.

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.

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.


SACRIFICIAL ANODES Sacrificial anodes on ship hulls and ballast/cargo tanks protects steel and preserves coatings.

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.

Geometric variations between thedifferent anodes types may occur.

Aluminium anodes• Capacity: 2651 Ah/kg• Consumption rate: 3.3 kg/Ayear• Specific gravity: 2.78 kg/dm3

• Closed circuit potential: -1100 mV vs Ag/AgCl/seawater


STANDARD FLUSH ANODESALUMINIUM AND ZINC

Most anode types and sizes can be supplied. Customized anode are available upon request.

Zinc anodes• Capacity: 780 Ah/kg• Consumption rate: 11.2 kg/Ayear• Specific gravity: 7,13 kg/dm3

• Closed circuit potential: -1030 mV vs Ag/AgCl/seawater

Standard ALUMINIUM flush anodes

Anode Weight (kg) Dimensions (mm)Type Gross Net L1 L2 H W2-AL 0.2 0.15 90 164 23 464-AL 0.4 0.3 120 210 28 62A-10 1.0 0.8 205 280 25 8215-AL 1.5 1.2 215 300 30 9525-AL 2.5 2.1 260 350 34 115A-25 2.5 2.1 305 400 43 100A-33 3.3 3.0 200 280 84 10043-AL 4.1 3.8 330 450 35 150A-50 5.0 4.3 425 530 38 117A-54 5.4 5.0 240 330 90 11060-AL 6.0 5.2 570 700 43 110A-80 8.0 7.0 625 730 40 12480-AL 8.0 7.5 350 450 62 15090-AL 9.0 7.8 930 1090 40 110A-116 11.6 10.0 785 900 46 123114-AL 11.4 10.6 600 700 79 120A-130 13.0 11.2 870 1000 45 123A-180 18.0 15.5 1220 1340 48 125170-AL 17.0 15.8 930 1060 40 110A-220 22.0 19.8 1090 1210 85 108350-AL 35.0 31.6 1920 2000 71 120399-AL 39.9 33.3 2500 2580 60 185

Standard ZINC flush anodesAnode Weight (kg) Dimensions (mm)Type Gross Net L1 L2 H W2-Z 0.22 0.17 98 140 13 345-Z 0.5 0.45 120 164 23 46

10-Z 1.0 0.9 140 210 28 62Z-18 1.8 1.7 155 230 24 8220-Z 2.0 1.9 165 210 30 90Z-30 3.0 2.8 245 320 25 7835-Z 3.5 3.2 220 300 30 96Z-51 5.1 4.6 310 400 32 8555-Z 5.5 5.1 260 350 33 113Z-85 8.5 8.1 395 500 33 98

102-Z 10.2 9.3 350 450 33 150Z-108 10.8 10.2 375 480 41 120155-Z 15.5 14.7 590 700 45 116Z-160 16.0 15.1 535 630 42 120Z-200 20.0 19.3 500 525 50 128Z-220 22.0 20.6 680 800 47 125235-Z 23.5 21.5 960 1060 40 120Z-270 27.0 25.3 785 900 53 125

Cathwell ASVisiting address: Kongshavnsgate 18, NO-3970 Langesund, Norway

Postal address: PO Box 68, NO-3993 Langesund, Norway

Tel. +47 35 96 78 50, [email protected] - www.cathwell.no

Cathodic Protection ∙ Electrolytic Antifouling

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