Shipping industry leaders who attended London International Shipping Week (LISW), which took place from 11–15 September, heard the case for water lubricated propeller shafts during an evening technical lecture organized by the Institute of Marine Engineering, Science & Technology (IMarEST).

On 13 September at the IMarEST’s London HQ, Thordon Bearings’ regional manager George Morrison, a chartered marine engineer with 23-years’ experience, presented a paper calling for full acceptance of water-lubricated propulsion across the global shipping industry.

Outlining how water-lubricated propeller shafts have been used since the earliest days of shaft-driven propellers, Morrison’s paper Water Lubricated Propulsion — A Case for Full Acceptance explored the pros and cons of current shaft lubricating methods. It proposed the most environmentally sustainable, cost-effective solutions available and also highlighted myriad onboard applications for grease-free bearings, such as deck winches, lifeboat davits and cargo cranes.

“The introduction of new pollution regulations has led to a return to seawater- lubricated propeller shaft bearing systems, especially for those vessels trading in US or Polar waters, where the discharge of oil from any oil-to-sea interface in quantities that may be harmful to the environment is restricted,” says Morrison.

“The IMarEST Technical Lecture during LISW provides an excellent opportunity to explain how new technology for polymer bearings, shafting materials and system packages not only increase bearing wear life and reduce ship maintenance costs, but can also keep our oceans clean.”

According to Morrison, when seawater- lubricated propeller shaft lines are used rather than oil-lubricated shafts or pods, operating costs are reduced substantially over the life of the vessel as there is no AFT seal, no lubricating oil, no storage of oil, no sampling of oil and no disposal of oil. Additionally, there are no costly seal repairs that can cost as much as US$300,000 per aft shaft seal.

David Loosley, Chief Executive, IMarEST, says: “The IMarEST’s overarching vision is one of a world where marine resources and activities are sustained, managed and developed for the benefit of humanity. The Institute is always in full support of those seeking to find the most environmentally sound solutions for activities that may impact the marine environment and water lubricated propulsion is one such solution that calls for consideration.”


A global leader in seawater-lubricated propeller shaft bearing systems, with over 35 years’ experience in this technology, Thordon Bearings is renowned for supplying high performance, oil and grease- free bearing systems to the global marine, clean energy, pump and offshore markets. Thordon Bearings is the only manufacturer of propeller shaft bearings to guarantee its award-winning COMPAC system for a 15- year wear-life. Thordon systems and bearings are available worldwide through over 85 agents and distributors.