In what marks a relatively new application for Thordon Bearings’ pioneering polymer material, Wilson Ship Management AS, a Norway-based ship manager, has replaced the greased bronze bearings on the hatch cover wheels of some of its dry cargo vessels with self-lubricating ThorPlas-Blue bearings.
Wilson, which operates Europe’s largest short sea fleet of about 130 general cargo vessels, has now converted eight vessels following the success of the first retrofit three years ago.
Tommy Holmgren, Sales Director, Duwel Group – Thordon Bearings’ authorized distributor in Norway – explained: “Wilson was not aware at first that the Wilson Wisla, which was purchased in 2019, was already operating with Thordon bearings in this application, but when they discovered it was Thordon, they ordered more for other Wilson vessels. To date, we have retrofitted ThorPlas-Blue bearings to the hatch cover wheels on a further seven vessels.”
Retrofits to Wilson Weser took place in 2020 and further installations to Wilson Borg, Wilson Leith (pictured), Wilson Tees, Wilson Alster, Wilson Goole, and Wilson Monsoon all took place in 2022 during scheduled drydockings. “The ship manager is closely monitoring performance but so far, the feedback is very positive. We anticipate increased interest for ThorPlas-Blue in this application,” confirmed Holmgren.
ThorPlas-Blue is commonplace in ships’ deck machinery, such as fairleads, winches, and lifeboat davit bearings, but as the material can withstand much higher pressures, hatch cover bearings are deemed an important and beneficial application.
Typically, a hatch cover’s wheel spindles, cleat spindles, hinge pins, hydraulic cylinder protective sheaths, cleat wedges, drive chain sprockets, toothed rack, and cylinder spherical bearings need to be properly greased at least once a month. This time consuming and messy operation is carried out to ensure hatch covers open and close smoothly and to prevent damage to cargo during loading and unloading. ThorPlas-Blue removes the greasing requirement.
With ocean sustainability and responsible shipping now very much on the regulatory agenda, Thordon Bearings’ environmentally focused products are being specified as part of a tranche of solutions and measures to reduce the environmental impact of operations. This successful application will open significant opportunities for Thordon and its ThorPlas-Blue line of self-lubricating bearings.
ThorPlas-Blue was developed as a maintenance-free solution to replace bronze bearings and to remove the need for grease in ship deck equipment. The elastomeric polymer material is designed to withstand pressures up to 45MPa (6,527 psi), though installation experience suggests the material can withstand much higher loads.
Anthony Hamilton, Thordon Bearings’ Technical Director, said: “By replacing traditional greased bronze bearings with ThorPlas-Blue, ship operators and managers benefit both environmentally and commercially. There is a zero-grease requirement and wear rates improve dramatically. The self-lubricating properties of the Thordon material mitigates against the risk of hatch cover failure due to bearing seizure, so you do see reduced repair and maintenance costs.”