About
For more than six decades, DURAMAX MARINE has been the global leader in water-lubricated propulsion bearing technology, delivering innovative marine systems trusted by commercial fleets, naval forces, offshore operators, dredging companies, and shipbuilders worldwide. Proudly engineered and manufactured in the USA, DURAMAX MARINE has earned an unrivalled reputation for engineering excellence, environmental sustainability, and uncompromising product performance. Through continuous investment in research, material science, and advanced manufacturing, the company continues to set the benchmark for propulsion system reliability across the global marine industry.
DURAMAX MARINE offers a comprehensive portfolio of engineered propulsion solutions including the world-renowned Johnson Cutless® water-lubricated bearings, advanced polymer bearing systems, shaft sealing systems, stern tube seals, stuffing boxes, compression packing, keel coolers, box coolers, heat exchange systems, and impact protection products. Every solution is developed using proprietary material formulations, precision manufacturing, and rigorous testing to deliver exceptional wear resistance, reduced vibration, superior shaft protection, and extended service life under the harshest operating conditions. DURAMAX continues to define the industry standard for environmentally friendly, water-lubricated propulsion technology, with its bearing systems installed in more vessels worldwide than any other comparable solution.
Driven by decades of engineering innovation and supported by an ISO 9001-certified manufacturing system, DURAMAX MARINE continues to develop next-generation propulsion technologies that improve vessel efficiency, simplify maintenance, and reduce environmental impact. From naval vessels and commercial ships to dredgers, tugboats, fishing fleets, offshore support vessels, and luxury yachts, DURAMAX products deliver proven reliability where uninterrupted performance is mission-critical. Combining advanced engineering with industry-leading technical expertise, DURAMAX MARINE remains the preferred choice for marine professionals seeking propulsion system solutions that maximise safety, efficiency, and long-term operational confidence.
Products
The Cutless brand is the most recognized water lubricated marine bearing around the world. Johnson Cutless bearing was the first and continues to be the only bearing to meet all MIL-DTL-17901C Class II requirements.
Duramax Marine high-quality standards, unmatched marine experience, and decades of water-lubricated rubber bearing research have resulted in performance records that other manufacturers only promise.
Johnson Cutless bearings are engineered with a proprietary formulation of extremely tough chemical and oil resistant nitrile rubber polymer lining, molded and firmly bonded into a naval brass or non-metallic shell. Grooves run the entire length of the rubber lining allowing for maximum lubricating water flow and dissipation of frictional heat.
DuraBlue water-lubricated stern tube bearings are manufactured using a unique synthetic reinforced composite that incorporates solid lubricants for superior operation and outstanding wear life in blue water applications.
The composite resin matrix was designed to withstand the rigors of seawater operation and frictional heat generated when used in stern tube propulsion systems.
DuraBlue is dimensionally stable, has a very low coefficient of expansion in extremely cold or tropical regions. DuraBlue is designed to tolerate edge loading and misalignment even with the heaviest loads. It is chemical and corrosion resistant and will not cause corrosion to housing.
ROMOR I was engineered for low friction and noise particularly at minimal journal velocities. It was field tested on the trident submarine and the results were outstanding – "no bearing-initiated hull noise at any speed". The potential for squeal and stick-slip was virtually eliminated, for smoother operation. ROMOR I low friction characteristics results in better energy efficiency and a remarkable increase in bearing and shaft life.
ROMOR I technology developed for the military is available in a radius-backed locking stave design for use in commercial marine round-bore stern tubes. It's the ecological answer that will help you meet the marine industries requirements for a clean new world, while dramatically cutting maintenance time and costs.
The Duramax Shaft Seal Systems are available for shafts from 3/4 inch to 6-3/4 inch diameter. The design features of this system eliminate problems that other systems experience, and with no lip seals or packing to change there is no maintenance. It is easy to install, with no need for constant adjustments once properly installed. Removal and replacement of the system is simple.
The DryMax Stern Tube Seal System was designed, built and tested by Duramax Marine in the USA. The seal is a water-lubricated axial shaft seal system constructed of the highest quality materials which have been engineered to deliver long service life.
The DryMax Shaft Seal is a reliable system that uses no grease or oil and is easy to install and maintain. It is a great addition to a full line of proven and reliable marine products developed by Duramax Marine and engineered to protect the environment
Johnson heavy-duty stuffing box is engineered and built to seal out seawater and give unmatched protection for your propulsion system. Its robust construction, highest quality alloys and precision machining gives it the ability to withstand long service life at sea. It's not uncommon for a Johnson Heavy-Duty Stuffing Box to last the life of the vessel.
