RetroLink™
Aluminum anode retrofit string for shallow water structures

In 2009, RetroLink's was used to retrofit the cathodic protection on over 120 structures in the Gulf of Mexico.

RetroLink is a cost-effective cathodic protection retrofit system comprising between 3 and 15 aluminum anodes cast directly on a heavy duty wire rope. The RetroLink is attached mechanically and electrically to a structure above the water line, allowing the string to then hang in the seawater with at least two anodes dragging in the mud. The installation is almost always diver-less, performed from a small vessel, and RetroLink can be used for any structure in less than 85 ft. of water.

Dependable - Despite the ease of installing a RetroLink, the system is incredibly robust. RetroLink is consistently able to resist category 2 hurricanes, often times remaining in service after category 4 storms. In fact 2 operators doing post hurricane inspections in 2009 found that 95% of their RetroLinks were still working after hurricanes Gustav, Ike, Humberto, Rita, and Katrina. The RetroLink is truly reliable cathodic protection for your offshore, inshore or marine structure with minimal installation expenditures.

Extremely Versatile - The RetroLink is designed to hang from a support that can be either welded or bolted on to the designated structure. The string is then attached and allowed to hand down with the anodes submerged. With two anodes trailing on bottom, sea movements are attenuated, and the string will not wrap around the structure. The RetroLink can be hung from any horizontal or vertical member. It can even be attached subsea, if necessary.

Adjustable In The Field - The wire rope core provides both the electrical conductivity through the anode system as well as a sound mechanical support. The strings are made with up to fifteen anode segments; these may be cut to length (often in the field) and deployed in many ways to provide cathodic protection just where it is needed. If additional anode material is laid in the mud, the system life can be extended to almost ten years. Links can be stored on the boat, to be cut to length and installed as necessary, especially during post-hurricane inspections.

Applications

Shallow Water Offshore Structures

Many offshore structures that sit in less than 85 f.s.w can have the CP replaced very cost effectively using the RetroLink system. The system can be quickly installed with a small topside crew: no diving is required. The system can provide 5 – 7 years of protection. RetroLinks have been used on everything from single pile caissons (pictured) to shallow water 4 pile structures.

Offshore Wind Turbines

Foundation piles may be placed up to 1 year before the transition structure is installed. During this period RetroLinks can provide protection for the existing portion of the structure. They can even be recovered and redeployed during periods of grid power interruption.

Docks, Harbors and Wharves

RetroLink systems are reliable and easy to maintain using small under-dock access vessels and equipment commonly found around such installations. A simple design guide enables the facility owner to apply adequate levels of cathodic protection following a simple field verification procedure. Links have been installed to provide cathodic protection to multiple bridge pilings in the past, whether reinforced concrete or steel.

$('#product-image').cycle('fade');

Key design points

Modular design

The modular concept allows for simple design: simply select zinc or aluminum anode material (depending on the salinity of your water). Zinc anodes are recommended if water is less that 12‰ full strength seawater (4.2 ppt Cl) for all other applications the aluminum RetroLinks are recommended.

Leader assembly

Used for above water suspensions use PVC coated wire rope for corrosion resistance. The modular design allows the hang elevations to be easily adjusted in the field.

Weld-on or Clamp-on support

The weld-on topside suspension assembly can fix to horizontal or vertical members. The isolator can be used to have Links protect offshore risers. Links can be attached subsea using a modified hang-off. A new clamp-on support is also available, complete with I-Clips to prevent crevice corrosion.

Hurricane Resistant

As of January 2009 Deepwater has recorded a total of 668 installed RetroLinks on 112 structures in the Gulf of Mexico alone. Since Hurricane Gustav, 12 of these structures have been inspected for CP readings, 11 are still protected - 1 is low.

Quality Control

Deepwater draws anodes from two local affiliate foundry locations, allowing us to strictly regulate QA/QC for all the aluminum and zinc anodes we use in our systems.