Innovative water-lubricated bearings for maritime sustainability

Thordon Bearings is known globally for its water-lubricated bearing systems, but the scale and diversity of its markets often surprise people. When asked which segments drive the company’s work today, Craig Carter explains that the portfolio spans three very different worlds. “We work across three distinct markets,” he says. “The first is Navy and Coast Guard fleets, including India, where reliability and predictable maintenance really matter. The second is the workboat market in places like the Mississippi River in the US, and the Manaus and Paraguay river systems in Latin America. These rivers are full of extremely abrasive, sandy water, and our bearings are built to perform in exactly those conditions. The third is the merchant fleet: containerships, tankers, bulkers, LNG carriers and cruise ships. Each segment has different needs, so we tailor our bearing grades to the water quality and vessel profile.” At the heart of Thordon’s product line are its polymer, water lubricated propeller shaft bearings.

Craig describes them as proprietary elastomeric polymers that combine the abrasion resistance of rubber with the mechanical strength of plastic. “We manufacture different bearing grades because a vessel sailing in clean ocean water needs something different from a workboat running through mud and sand. And in addition to shaft bearings, we also produce water-lubricated seals and grease free polymer bushings for deck equipment like winches and fairleads. It allows ships to eliminate grease lubrication in multiple places.”

What makes Thordon’s bearings stand out in a competitive market? Craig says the difference becomes clear when customers evaluate lifecycle performance. “In abrasive environments, many conventional bearings last maybe three years. Ours often run for six years or more. That means one less dry-docking cycle, and that alone is a major commercial advantage. Even if our initial price is slightly higher, the operating cost is far lower. There’s no lubrication oil to buy, no risk of oil leaks, no environmental penalties and much less maintenance work for crews. Ultimately the total cost of ownership is the lowest in the propulsion bearing space.” As ship design evolves toward hybrid systems, shaft generators and new propulsion layouts, Thordon has been rethinking the shaftline architecture itself. Craig describes a recent engineering leap made in collaboration with ABS, Cedari of China and the National Technical University of Athens. “We’ve designed a stern-tubeless water-lubricated shaft system. By eliminating the traditional stern tube, the propeller shaft becomes shorter and ship designers gain more flexibility. That extra internal space can be used for cargo, for a larger engine room or to integrate shaft generators. The whole system reduces capital and operating costs, improves EEDI and boosts fuel efficiency. ABS granted Approval in Principle in 2022, and we’ve already quoted major shipyards in China, South Korea and the U.S.”

One of the features Craig considers most transformative is the ability to conduct maintenance while the vessel remains afloat. “This is one of the biggest commercial advantages,” he says. “Because the maintenance area is accessible from inside the vessel, you don’t need to drydock to inspect or replace the bearing. Operators can trim the vessel to raise the propeller or use underwater sealing support from certified diving teams. We’re talking hours instead of days, and no revenue lost during maintenance.” Sustainability is driving ship design worldwide, and Craig emphasizes that Thordon’s systems directly support those goals.

“There’s zero oil discharge below the waterline, so pollution risk disappears. The lower shaft friction we’ve proven with NTUA testing delivers fuel savings, and vessel efficiency improves because you can carry more cargo or gain room for systems like shaft generators, carbon capture or wind-assist. It’s a decarbonization solution that also cuts operating costs, which is exactly what shipowners want.” India plays an increasingly important role in Thordon’s global footprint, and Craig speaks warmly about the company’s directly support those goals. “There’s zero oil discharge below the waterline, so pollution risk disappears. The lower shaft friction we’ve proven with NTUA testing delivers fuel savings, and vessel efficiency improves because you can carry more cargo or gain room for systems like shaft generators, carbon capture or wind-assist.

It’s a decarbonisation solution that also cuts operating costs, which is exactly what shipowners want.” India plays an increasingly important role in Thordon’s global footprint, and Craig speaks warmly about the company’s presence in the region. “India is a very important market for us. We have strong partnerships with the Indian Navy and Coast Guard, who value reliability and reduced maintenance disruption. The country’s maritime sector is also growing in ship repair, workboat operations and port services, where water-lubricated, low-maintenance systems are a perfect fit.

We are expanding our technical service capability, working closely with public and private shipyards and supporting operators who are focused on lifecycle efficiency and sustainability compliance. India isn’t just a customer base. It’s becoming a strategic partner in maritime innovation.” Despite the strong case for water-lubricated systems, Craig acknowledges one challenge: shipyard bandwidth. “Most major shipyards are full until 2028, which reduces their appetite for design changes even when the benefits are clear. Owners are already convinced. The next step is working closely with shipyards and naval architects to integrate these solutions into their standard designs. We’re making progress, and we believe the first full commercial installations will happen soon.”

As the industry pushes toward greener, smarter propulsion, Craig Carter sees a clear role for Thordon’s technology. It is a role grounded not only in environmental responsibility but in hard commercial logic. “When you can improve sustainability, reduce operating costs and avoid unnecessary dry dockings, the conversation becomes very simple. Owners want solutions that make sense on every level. That’s what we aim to deliver.”