Thordon Bearings has secured a significant contract to convert the rubber tailshaft bearings across an entire fleet of Panama-operating tugs, pilot vessels, and workboats to water-lubricated polymer bearings.
The agreement with the unnamed operator follows the successful retrofitting of Thordon’s SXL tailshaft bearings to twelve of its twin-screw tugs last year during scheduled dry dockings.
The remaining 32 vessels will now be converted in batches at planned maintenance intervals over the next four years.
For the first batch of retrofit conversions, Thordon will supply a total of 62 bearings machined to fit shaft diameters ranging from 63.5mm to 101mm(2.5in to 4.5in). However, the scope of supply also includes Thordon’s ThorPlas-Blue bearings for tiller arms and jockey bars and SXL rudder bearings, both of which operate without the use of grease.
All of Thordon’s polymer bearings require neither grease nor oil for lubrication. Yet, while environmental protection was a major factor in the decision, so too was bearing longevity and reliability.
Interoceanic waterways tend to be very abrasive environments, which are not ideal for bronze-backed rubber bearings. The bronze outer shell and the steel housing are prone to galvanic corrosion, resulting in non-budgeted maintenance costs and drydockings.