Post on 28-Nov-2014
MARINECATHODIC
PROTECTION
A Survey Article by ELTECH Corporation
Marine Corrosion
Today, much of our infrastructure built upon steel components is seriously threatened by a destructive and persistent enemy: corrosion. If not properly protected, your marine facility is corroding right now as you read this web page. The rate of corrosion for clean, bare steel is at least 5 mils per year. This loss in material thickness can be greatly accelerated by variations in water composition, oxygen concentration cells associated with marine growth, and water velocity.
Many marine facility owners mistakenly believe that the coating of all submerged steel eliminates the need for cathodic protection. However, as much as 50% of the coating on a steel marine structure can be damaged, or completely removed during construction. Even undamaged coatings suffer from the presence of microscopic pinholes, which lead to the development of concentrated areas of corrosion. This severe form of pitting corrosion can have corrosion rates as high as 50 mils to 80 mils per year - resulting in complete penetration of 1/4" steel plate in under four years.
Cathodic Protection
The preferred technique for mitigating marine corrosion, based on historical performance and measurable results, is cathodic protection (CP) - the practice of using electrochemical reactions to prevent the corrosion of steel structures. The reason for increased acceptance: cathodic protection prevents corrosion on underwater structures.
In theory and practice, the implementation of a CP system is quite simple. Assuming you already have corroding steel in seawater, all you need is an anode, a power supply, and engineering talent. A
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protective circuit is accomplished between the anode, steel (cathode), power supply and electrolyte (seawater).
Impressed Current vs. Sacrificial
Standard industry practice for cathodic protection in new construction includes the installation of sacrificial anodes, such as aluminum and zinc. These types of anodes will typically provide a 10 to 20 year service life before requiring replacement. When retrofitting or replacing these existing CP systems, the most cost effective system is impressed current anodes, which require an external power source for their operation. The ease of installation, enhanced performance and lower installed cost of impressed current anodes make them the ideal CP system for retrofitting most structures.
Typical Anode Delivery Systems
On the design basis of maximum current distribution for the lowest possible cost, with the most long-term reliability, ELTECH has developed numerous anode current delivery systems suited for a variety of facility types and anticipated operating conditions. The following are but a sample of the many delivery systems commercially available. Our design engineers are likewise capable of creating custom systems to suit the requirements of your marine facility.
Pile Mounted Anodes
Pile Mounted Anodes are designed for efficient current distribution in and around pilings where the complex geometry of the facility precludes remote placement of the anodes. These delivery systems are suitable for direct attachment to pilings. The Flat Back Pile Mounted Anode was designed specifically for H-Piles, and can also be configured for installation on sheet piling.
Disk Anode
The Disk Anode was designed in conjunction with the U.S. Army Construction Engineering Research Lab for use on navigational locks and dam gates. This anode system is also suitable for use on seawater intake structures, vessel internals, and sheet piling when shoreside access is possible.
Retractable Mount
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For installations where it is deemed necessary to access the anode for periodic maintenance, or when current is only required on a periodic basis, the retractable anode allows the user to easily retrieve the anode. The above illustration is rotated by 90 degrees.
Sled Anodes
Anodes mounted on the sea bed typically afford the best spread of protection on a marine structure. Sled anodes can be designed for operation in either seawater or buried in the mud. The Post Tension Sled was developed to insure anode operation out of the mud when resting in silty and soft sea beds. By adjusting the height of the concrete sled, the mesh anode sled can also be designed for operation out of the mud. The advantage of this type of sled is its low profile, thereby limiting the potential for damage by anchors, fishing nets, etc.
Suspension Anodes
Suspension Anode Delivery Systems allow for strategic placement of anodes in and around a marine facility, providing optimum distribution of current. Many suspended anode systems are also suitable for mounting on pilings, or other structural steel.
Rod Anode
Although incorporated into a variety of anode delivery systems, the rod anode is most commonly used for the cathodic protection of seawater intake structures and vessel internals.
Background on ELTECH
Marine CP Technology
Proprietary technology, in tandem with advanced products and engineering, position ELTECH as a leading cathodic protection materials supplier.
ELTECH, the manufacturer of ELTECH LIDA mixed metal oxide anodes, benefits from the substantial resources of its parent, ELTECH System Corporation, which is the world's leading
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developer and producer of DSA technology for the chlor-alkali and other electrochemical industries. ELTECH Corporation's unique products and innovative systems have been halting corrosion in steel-reinforced concrete and conventional offshore and in-shore structures since 1974.
Mixed Metal Oxide Anode Technology
ELTECH LIDA anodes are comprised of a titanium substrate with a mixed metal oxide coating. The mixed metal oxide is a crystalline, electrically conductive coating that activates the titanium and enables it to function as an anode. This coating has an extremely low consumption rate, measured in terms of milligrams per year. As a result of this low consumption rate, the anode dimensions remain nearly constant during the life of the anode, providing constant levels of performance for the duration of the anode design life. Due to the ductility of the titanium substrate, a wide range of anode shapes suitable to the structure to be protected are possible, such as wire, rod, tubular, disk and mesh configurations.
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Impressed Current Anodes for Cathodic
Protection
[ Impressed Current Anodes | Galvanic Anodes | Cables & Accessories | DC Power Supplies || Polarization Cells | Test Stations | Reference Electrodes | Instruments & Test Equipment |
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| Pipeline Monitoring systems | Insulating Materials | Pipe Coatings & Tape | Misc. Products ]
Anodes - Cast Iron
Anotec Solid High Silicon Cast IronAnotec Tubular High Silicon Cast IronAnotec High Silicon Iron Tubular Anodes Centertec Z-SeriesAnotec Small High Silicon Cast IronDischarge Guide for Anotec AnodesTechnical Paper, “Effect of Microstructure on High Silicon Cast Iron”
Anodes - Graphite Farwest Center Connected Graphite Anodes
Anodes - Mixed Metal Oxide
Lida Tubular AnodesLida “One” Tubular AnodesLida Wire AnodesLida Pack Canistered Wire AnodesLida Rod AnodesLida Disk AnodeLida VentralizerLida Marine Cathodic Protection Information
Anodes - Platinum Anomet Platinum Clad Anodes
Anodes - Specialty Anode Systems EDI Linear Anode Systems
EDI Model RI-ICE Pack Impressed Current Anode
AnodeFlex Flexible Anode Systems Overview AnodeFlex 850 Flexible Anode SystemAnodeFlex 1500 Flexible Anode System
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Splice Kits for AnodeFlex 1500 Linear Anode System
Backfill
Asbury Carbon Anode Backfill Overview of Loresco Earth Contact BackfillsLoresco SC-3® Super Conducting Earth Contact BackfillLoresco SC-2® Super Conducting Earth Contact BackfillLoresco DW-1® Earth Contact BackfillLoresco SWK® Earth Contact BackfillLoresco SW® Earth Contact BackfillLoresco SWS® Earth Contact BackfillLoresco FlexFill™ Free Flowing Earth Contact BackfillLoresco EnviroCoke IV™ Conductive Carbon GroutLoresco PermaPlug™ Environmental Earth SealLoresco AllVent™ Deep Anode Vent SystemCalculating the Amount of Coke Breeze in a Vertical Hole
Anode Options
Heat Shrinkable Anode CapsAnode Canisters
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Galvanic Anodes for Cathodic Protection
[ Impressed Current Anodes | Galvanic Anodes | Cables & Accessories | DC Power Supplies || Polarization Cells | Test Stations | Reference Electrodes | Instruments & Test Equipment |
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| Pipeline Monitoring systems | Insulating Materials | Pipe Coatings & Tape | Misc. Products ]
Anodes - Aluminum Aloline Aluminum Anodes by Farwest
Anodes - Magnesium
UltraMag High Potential Magnesium Anodes by FarwestTech Paper: Magnesium Anode Performance - The Farwest UltraMag High Potential AnodeProMag Standard Potential Magnesium Anodes by FarwestExtruded Magnesium Anodes by TimmincoSpecialty Magnesium Anodes
Elektron Modular High Performance Anode for Offshore Application
Anodes - Zinc
Zinc Anodes for Marine ApplicationPlattline Zinc Ribbon Anodes for Cathodic ProtectionPlattline Zinc Ribbon Anodes for AC MitigationPlattline Zinc Ribbon Anodes for Above Ground Storage TanksPlattmatt Zinc Ribbon Anode Grounding MatsTechnical Practices for Zinc Ribbon Anode ConnectionsZinc Caps by Mars
Anode Backfill Galvanic Anode Backfill by Farwest
Anode Accessories
Fiberglass Deck Mounts for Water TanksAnode Mounting Assemblies
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Cable, Splicing Products,Cable Attachment
& Accessoriesfor Cathodic Protection
[ Impressed Current Anodes | Galvanic Anodes | Cables & Accessories | DC Power Supplies || Polarization Cells | Test Stations | Reference Electrodes | Instruments & Test Equipment |
| Pipeline Monitoring systems | Insulating Materials | Pipe Coatings & Tape | Misc. Products ]
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Cable for Cathodic Protection
High Molecular Weight Polyethylene (HMWPE) CableDual Jacketed Halar / HMWPE CableDual Jacketed Kynar / HMWPE Cable
Cable Splicing Materials
3M Splice Kits for Non-Shielded Cable3M Direct Bury Splice Kits
King Innovation DryConn® Waterproof Direct Bury Lug King Innovation DryConn® Waterproof Direct Bury 6 Yellow ConnectorRoyston SpliceRight Splice Kits
Cable Attachment
Erico Cadweld Cathodic Protection Connection Erico Cadweld Plus Exothermically Welded ConnectionErico 7-lb Cordless Rail Grinder for Caldweld Connections BAC Easy Bond Pin Brazing SystemBAC Easy Bond Reach System for Buried PipelinesTapecoat / Royston Handy CapTapecoat / Royston Handy Cap IPVEPAC Multi-Stage In-Car Charging System for BAC Brazing Units
Miscellaneous Products Warning Tape for Direct Burial
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Phone: 310-532-9524Fax: 310-532-3934Privacy Statement
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DC Power Supplies& Accessories for
Cathodic Protection
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| Pipeline Monitoring systems | Insulating Materials | Pipe Coatings & Tape | Misc. Products ]
Cathodic Protection Rectifiers
Cathodic Protection Rectifiers UL Approved Rectifiers Model ES / TufBox Rectifiers
Watertight 200 Watt Utility Rectifier
Pulse Rectifiers Model 2015 Air Cooled Pulse Rectifier by Farwest
Model 3015 Oil Cooled Pulse Rectifier by Farwest "Well Casing Cathodic Protection Utilizing Pulse Current Technology."Corrosion 2004 Conference paper reprinted with permission of NACE International."Corrosion Measuring Techniques Confirm Effectiveness of Pulse Cathodic Protection for Buried Steel Pipeline."Corrosion 1999 Conference paper reprinted with permission of NACE International.
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"Evaluating Oil Well Casing Corrosion Using Well Head Current Measurements."Reprinted with permission of Ted Doniguian, author."Protecting Semi-Close Spaced Oil Well Casings With Multi-Module Pulse Cathodic Protection."Reprinted with permission of Ted Doniguian, author.
Rectifier Cabinets POWERHOUSEplus UL-Approved, Ornamental Rectifier Cabinet by Farwest
Alternative Power Supplies
Solar Power Supplies for Cathodic Protection
Solar Power Supply Charge / Output Controllers
Solar Power Supply Components Thermoelectric Generators by Global
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Test Stations, Junction Boxes, Line Markers & Coupons for Cathodic
Protection[ Impressed Current Anodes | Galvanic Anodes | Cables & Accessories | DC Power Supplies |
| Polarization Cells | Test Stations | Reference Electrodes | Instruments & Test Equipment | | Pipeline Monitoring systems | Insulating Materials | Pipe Coatings & Tape | Misc. Products ]
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Product categories within this page:
Test Stations, above grade
Test Stations, flush mount
Junction BoxesShuntsLine MarkersCouponsWashers
Test Stations, Above Grade
Big Fink Test Station by CottLittle Fink Test Station by CottFat Fink Test Station by Cott Finklett & Fink Plate Test Station by CottFink ZapGard Test Station by CottFink Bonder Resistance / Bonding Test Station by CottTop Hat Test Stations by Tinker & RasorScepter Test Station by CarsoniteTest Station Markers by CarsoniteTestox Stations by GeromeTufBox Stainless Steel Test Station Enclosures
Cathodic Protection Accessories by Tinker & Rasor
Test Stations, Flush Mount Flush Fink Test Station by Cott
Street Fink Test Station by CottHandley Cathodic Test StationsC.P. Test Services Test Stations
Detectable Test Station by AMPro
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Concrete Test Box by Farwest
Bingham & Taylor Cathodic Test Stations
Junction Boxes
Conventional & Custom Junction Boxes by FarwestConventional & Custom Junction Boxes by UniversalCottBox Non-Metallic Electrical Enclosures
TufBox Stainless Steel Junction Box Enclosures
Shunts
Cathodic Protection Shunts by FarwestCathodic Protection Shunts by Cott
Cathodic Protection Shunts by Tinker & Rasor
Line Markers
CottMark Pipe & Cable Marking SystemCottMark Graphical MarkersCottMark Designer MarkersCottMark Flat MarkersCarsonite Utility MarkersCarsonite Introduction to Utility Markers
Coupons
Model UC Underground CP Coupon by EDIIR-Free Coupon by M.C. MillerFink Probe Integrated Steel Coupon
Washers MCM Color-coded Insulating Washers
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Reference Electrodesfor Cathodic Protection
[ Impressed Current Anodes | Galvanic Anodes | Cables & Accessories | DC Power Supplies || Polarization Cells | Test Stations | Reference Electrodes | Instruments & Test Equipment |
| Pipeline Monitoring systems | Insulating Materials | Pipe Coatings & Tape | Misc. Products ]
Portable Reference Electrodes & Accessories
Tinker & Rasor Portable Reference Electrodes & AccessoriesM.C. Miller Portable Reference Electrodes & AccessoriesM.C. Miller Leak Stop Gel for Portable ElectrodesM.C. Miller Silver Chloride Electrode KitsEDI Model IT Portable Reference ElectrodeStaperm Portable Reference Electrode by GMCStaperm Heavy Portable Reference Electrode by GMCStaperm Portable Salt Water Reference Electrode by GMCStelth 3 Permanent Portable Reference Electrode by BorinStelth 4 Permanent Portable Reference Electrode by BorinCollins Portable Reference Electrode
Permanent Underground Reference Electrodes
Farwest SP-150 Reference Electrode for In-Soil InstallationFarwest Dual-Element Permanent Reference ElectrodeEDI Model UR Regular Permanent Reference ElectrodeEDI Model US SlimLine Permanent Reference ElectrodeEDI Model UL LongLife Permanent Reference Electrode
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Staperm Permanent Ceramic Reference ElectrodesStaperm Permanent Prepackaged Reference ElectrodesStelth 2 Permanent Ceramic Reference ElectrodesStelth Permanent Reference Electrodes
Permanent Underwater Reference Electrodes
Farwest FW-250 Permanent Electrode for In-Water InstallationEDI Model IR Permanent Reference Electrodes for Fresh or Salt WaterEDI Model IP Pipe-Type Permanent Reference ElectrodesStaperm Permanent Fresh Water Reference Electrodes by GMCStaperm Permanent Salt Water Reference Electrodes by GMCDeltaperm Apache Deep Salt Water Reference Electrode by GMCStelth Permanent Fresh & Salt Water Reference Electrodes by Borin
Specialty Reference Electrodes
Antimony Electrode for pH Measurement by AgraEDI Model FA Adjustable Through Wall Reference ElectrodesEDI Model FS Standard Through Wall Reference ElectrodesEDI Model FE Through Wall Reference Electrode for Extreme EnvironmentsEDI Model T Tube Sheet Reference ElectrodesStaperm Permanent Through Wall Reference Electrodes by GMCStaperm Contact Eliminator, Gelatin Filled Casing by GMCStelth 7 IR-Free Permanent Reference Electrodes by Borin
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Pipeline Corrosion Monitoring Systems
[ Impressed Current Anodes | Galvanic Anodes | Cables & Accessories | DC Power Supplies || Polarization Cells | Test Stations | Reference Electrodes | Instruments & Test Equipment |
| Pipeline Monitoring systems | Insulating Materials | Pipe Coatings & Tape | Misc. Products ]
ScadaNET Network - Wireless & Internet Based Monitoring & Control Systems
ScadaNET CellularRMU - Complete Rectifier Control & Monitoring Unit
ScadaNET RMUvi - Basic Wireless Rectifier Monitoring
ScadaNET P2S - Battery Powered Pipe-to-Soil Test Point Monitor
ProActive Pipeline Integrity System by MC Miller Co. #1
ProActive Pipeline Integrity System by MC Miller Co. #2
Data Link Pro for SinCorder by MC Miller Co.
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Privacy Statement Gardena, CA 90248-3215, USA
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Polarization Cells &Overvoltage Protection
[ Impressed Current Anodes | Galvanic Anodes | Cables & Accessories | DC Power Supplies || Polarization Cells | Test Stations | Reference Electrodes | Instruments & Test Equipment |
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Dairyland Overview of Solid State DC Isolation & AC Grounding Products Dairyland Applications Dairyland Industries Dairyland Frequently Asked Questions (FAQ) Dairyland PCR Polarization Cell Replacement Dairyland PCRH Polarization Cell Replacement for Hazardous Locations Dairyland OVP Over-Voltage Protector Dairyland OVP2 Over-Voltage Protector Dairyland ISP Isolator / Surge Protector Dairyland RP Rectifier Protector Dairyland RCS Reverse Current Switch Dairyland GCM Gradient Control Mat Dairyland SSD Solid State Decoupler The Kirk Cell for Protection of Cathodic Protection Circuits
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Farwest CorrosionControl Company sales@farwestcorrosion.com
Phone: 310-532-9524Fax: 310-532-3934Privacy Statement
MAIN OFFICE1480 West Artesia Blvd.
Gardena, CA 90248-3215, USA
Toll Free: 888-5FARWEST (888-532-7937)
Back to Farwest Materials main page.
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