Seawater, that is available in plenty, economical and safe, is the most environmentally acceptable lubricant claims Thordon Bearings Inc., the leading manufacturer of seawater lubricated bearings for the global marine industry. The US Environmental Protection Agency is enforcing that all vessels over 24m operating in US waters must switch over to EALs in all oil-to-sea interfaces before their next dry-docking. Thordon questions why switch over to costly bio-lubricants when seawater is widely available and 100% free?
The seawater lubricates the bearings to ensure the smooth, effective and safe operation of the vessel. The seawater-lubricated COMPAC system has a wear life of fifteen years and reduces a ship owner’s annual operating and maintenance costs substantially, compared to an EAL-lubricated metal bearing and two seal system.
Thordon Bearings found in its recently published comparative research, that EALs – vegetable oils, synthetic esters and poly alkylene glycols – are over 7 times more expensive than the mineral oils typically used in oil-lubricated propeller shaft bearing systems.
Between 130 million to 240 million litres of operational oil lubricant is leaked into the oceans each year and needs to be replaced. Whilst the need to limit the impact that traditional mineral oil lubricants have on the marine environment is obvious, Carter indicated that some analysts and ship owners have already questioned the performance and reliability of EALs.
In DNV GL’s newsletter 12-77, the classification society states that biodegradable oils deteriorate when mixed with water and the inevitable result is that the lubricating capabilities will be adversely affected. The seawater-lubricated COMPAC system completely avoids this problem.
The technology has been introduced in a hurry and before thoroughly testing, so there are no guarantees about their longevity. Seawater is the ultimate EAL.
Source: Thordon Bearings