Cathodic protection systems
for offshore platforms
In 2010, Deepwater conducted cathodic-protection retrofits for 75 structures worldwide.
Deepwater designs and manufactures cathodic protection (CP) systems for new structures and anode replacement systems for aging offshore assets with failing corrosion protection. Having rewritten the "CP retrofit textbook" by focusing on installation methods alongside current requirements, Deepwater can retrofit a structure's cathodic protection system more quickly and efficiently, reducing the cost to the operator by up to 60% below traditional methods. As the majority of the world's offshore infrastructure begins to reach the end of its original designed life, it is increasingly important to address corrosion control for valuable offshore assets. Our N.A.C.E.-certified team of engineers and cathodic-protection designers have provided, supplemented or replaced the CP systems on every type of brown-or-green-field asset currently in operation.
For new structures - For new-build projects, we provide standard aluminum platform anodes, made at one our certified ISO 9000 anode foundries. All foundry facilities are located only a few miles from where our design team and engineers manage each project, ensuring that strict QA/QC oversight is observed for all anode materials used in our systems.
Sacrificial anode retrofits - For sacrificial retrofit situations where impressed-current cathodic protection (ICCP) is not an option, we usually recommend the RetroPod system, which has a long record of success. Because it is connected quickly with the RetroClamp, a RetroPod can be installed in under half the time that a traditional Clamp-on anode requires. In depths less than 200 feet, Pods can usually protect an entire structure from the sea floor. For platforms in depths less than 90 feet, Deepwater has invented the only reliable hanging anode system on the market. Called RetroLink, the anode string can withstand category 2 and 3 hurricanes and routinely provides adequate cathodic-protection levels for 5 years or more.
Impressed current retrofits - For anode retrofit projects where the designer is required to provide a lot of cathodic protection current (such as structures that are larger or in deeper waters), we employ the RetroBuoy ICCP retrofit system. Providing as much as 400 amps of CP for up to 25 years, it is the most effective and efficient cathodic protection anode sled on the market. It'sideal for any large structure, complex, or FPSO with an available power source. Operators have used the RetroBuoy on 4 continents; it is quickly becoming standard practice for any sizable CP retrofit project.
Related technical information
Offshore Cathodic Protection 101 (Paper)
A brief tutorial about the science of cathodic protection as it relates to the offshore oil and gas industry, complete with diagrams, chemical equations, etc.
Offshore CP System Management (Paper)
As offshore structures around the world are aging and in many cases reaching the end of their designed lives, operators are looking for ways to reduce costs in managing the corrosion protection systems and other asset-integrity programs.
Impressed Current Cathodic Protection Retrofits (Paper)
It has long been recognized that an impressed-current design can offer significant economic advantages over galvanic anodes in certain types of cathodic-protection systems. Historically, ICCP systems have been plagued by poor design, but installation costs offshore have forced designers to go back to the drawing board.
Cost Saving Offshore CP Retrofit Methods (Paper)
Many offshore structures, platforms and pipelines will require a cathodic protection retrofit in the next several years. This paper describes some concerns associated with retrofitting CP for aging offshore assets.
Maximizing the Value of Underwater CP Surveys (Paper)
Abstract: Since the measurement of cathodic protection potentials on offshore structures is a regulated activity and must be done, it makes sense to get as much benefit from the survey as possible.
Platform cathodic protection products
Platform anodes
For new structures, Deepwater provides aluminum anodes, manufactured at one of our foundry facilities. Each ISO 9000 certified foundry is located just minutes from the engineers and designers managing the project, allowing Deepwater to oversee QA/QC on every anode.
RetroBuoy™
For large structures, the RetroBuoy cuts project costs by delivering more protection with greater efficiency. By using impressed-current cathodic protection, one typical RetroBuoy can deliver up to 400 amps of corrosion protection – enough to protect 80,000 ft2 of steel.
RetroPod™
For sacrificial retrofits, the RetroPod system provides aluminum anodes arranged in stable, self-contained 'pods' on the seabed. Though many competitors have copied the Pod, the system also relies on the RetroClamp, which provides rapid, reliable connection to the structure.
RetroClamp™
A versatile component, the RetroClamp allows divers or ROV to attach cathodic protection anodes to a platform quickly and reliably. The RetroClamp is a standard, off-the-shelf item manufactured in-house at Deepwater for any standard or custom-diameter tubular member.
RetroLink™
For shallow water, the RetroLink system is a string of anodes installed topside and hung to the sea floor. Designed for minimal structures and caissons, Retrolink can be applied to platforms in less than 85 feet of water to provide up to 5 additional years of protection with no subsea intervention.
Dual clamp-on anodes
Designed for early retrofits to eliminate underwater welding, dual clamp-ons have been retired as a primary retrofit solution in favor of even more economical methods. They are still used to supplement RetroPod current near the surface, or when bottom conditions limit the number of pod placements.