Thordon Bearings has been advocating the use of green technologies to help slash operation costs for shipowners.



In a new paper, it compares the advantages and disadvantages of both oil lubricated and water lubricated propeller shafts, explaining how a seawater lubricated system can represent significant cost savings for shipowners throughout the life of the vessel.



“A seawater lubricated propeller shaft bearing system is the only system that guarantees compliance and has zero impact on the aquatic environment,” said Craig Carter, Thordon Bearings’ director of marketing and customer service.

“No expensive environmentally acceptable lubricants are required and there is no need for periodic aft seal replacement or aft liner maintenance.”



Appropriate monitoring



He said that with the appropriate monitoring, these shafts can remain in-situ for 18 years or more. There is no need for daily oil sampling, and there is no oily residue to be disposed of.



This means that operating costs are substantially lower for open seawater systems compared to a sealed oil/EAL system, and day to day operation is far simpler.”



Faced with the possibility of environmental fines due to oil leakage from worn or damaged shaft seals, together with increased OPEX due to the higher cost of environmentally acceptable lubricants (EAL), Mr Carter’s paper ‘Why Seawater is the most practical propeller shaft EAL - technical and commercial benefits for shipowners’ could reassure some shipowners that a cost-effective alternative is available.



So far, over 2,000 ships have been fitted with Thordon’s seawater-lubricated shaft systems.