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CHANCE® Helical Anchors for Marine & Mooring Applications
Helical anchors are a versatile, eco-friendly, easy to install, and
cost-effective technology for marine and mooring applications
First used in the marine environment to secure oil pipelines to the ocean floor, helical anchors are now utilized for floating docks, aquaculture farms, tiebacks, boat moorings, bulkheads, fixed walkways, floating solar farms, and more.
Depending on the anchor size and soil conditions, you can anticipate holding from 1000 to 2500 pounds with a small round rod anchor, and upwards of 20,000 pounds with a larger square shaft anchor. Bridled together and sized accordingly, these systems can be engineered to secure even larger loads.
Since they are reusable and have a small installation footprint, Chance anchors are very eco-friendly. They are made from recycled steel and are recyclable.
The installation footprint for a Chance anchor is very small and, once installed, it stays put. Unlike a block or mushroom anchor, a Chance helical anchor is not affected by a sloped bottom and will not drag under heavy gusts or other forces. This protects the seafloor and prevents damage to eel grass and other marine life.
“We’ve installed them in state parks where minimal equipment was used,” explains Captain Chad Walder of Waterfront Contracting in Franklin Lakes, New Jersey. “We didn’t need big cranes or heavy equipment to lift big concrete blocks. We were able to use submersible equipment held by two workers instead of heavy equipment.”
EASY TO INSTALL
Anchors are installed into the marine floor from the surface by work boats with drill rigs or divers utilizing submersible equipment and anti-torque devices. The helix plates are installed through the silt into good bearing soils, and lines are connected to the mooring or platforms above.
“We use two installation methods, the first being a torque motor that’s mounted on a crane where we drive the anchors in from the surface. The second method is a submersible torque motor that a diver uses and operates from below the surface. That’s generally used for deeper applications,” said Walder.
With Chance helical anchors, moorings can be moved and repurposed elsewhere with little disturbance to the seafloor. Captain Walder explains, “The A.B. Chance anchors can be removed very easily. We use the same equipment that we use to install them with in reverse and we back them out like a big screw. We have just removed a mooring field that has been in the water for over 25 years. The A.B. Chance anchors are going back in for at least another 25 years. They look the same as when we put them in in the 90s.”
The longevity of Chance anchors and the installation benefits, contribute to a lifelong cost of ownership that provides savings over many other technologies.
Peter Morrison, President of Helix Mooring, has been working with Chance anchors for decades. When asked about why his customers choose Chance over other technologies, he shared, “The A.B. Chance anchor has always been a very competitively priced product. The transportation costs are less as well as the actual installation costs can be less because instead of moving a thousand pound concrete block, you’re installing a hundred pound square shaft Chance anchor.”
Anchors age slowly. Since most of the anchor is below ground, oxidation exposure is limited, making it an excellent long-term investment.
With 4 to 5 times the holding strength when compared to alternative technologies, insurance companies have even offered special incentives to boat owners who use helical moorings in hurricane-prone areas.
Discover for yourself why installers continue to choose Chance for decades of installations in marine and mooring applications.
“Helix Mooring buys exclusively from A.B. Chance and its anchors because of its high quality product,” said Morrison. “All of their products are made in the USA. Also the people that manufacture the product and stand behind the product, their customer service is very responsive. We also have an engineering team at our fingertips that can assist us when we run into challenges on projects. And their sales team, always innovative, always looking for new ways and more efficient ways to provide our customers with the best possible solutions.”
Watch the video to see a Chance underwater mooring installation:
Read more about marine applications for Chance anchors: https://blog.hubbell.com/en/chancefoundationsolutions/tag/mooring