Bulker built in 1952 converted with Thordon bearings


(BURLINGTON, Ontario) — The oil-to-water lubricated tailshaft conversion Thordon Bearings carried out last year to the 26,260-dwt Great Lakes Fleet-managed bulk carrier SS John G. Munson has successfully completed its first season as a diesel-powered ship.

The shaft conversion of the 1952-built self-unloader formed a key part of the 12-month power conversion project completed last year by Fincantieri’s Bay Shipbuilding yard, in Sturgeon Bay, Wis.

The vessel’s steam propulsion plant was replaced with an energy-efficient medium-speed diesel arrangement. Major works also included the removal and replacement of the vessels’ tailshaft, stern tube, propeller and hub. Thordon Bearings’ supplied its COMPAC water-lubricated propeller shaft bearings, a water quality package, which conditions the lubricating water, and shaft protection system ThorShield.

Mechanical Supply Inc. and Belthor Systems, members of Thordon’s distributor network, worked closely with Great Lakes Fleet on the detailed design, while Avalon Marine, another Thordon distributor, was instrumental in working with classification society ABS to trial COMPAC under its notation for extended shaft withdrawal.

SS John G. Munson became the first ABS-classed vessel with a water-lubricated propeller shaft arrangement to operate under its TCM (tailshaft condition monitoring) notation.

In early 2016, the Interlake Steamship Co. converted its last steam-powered vessel, the 1959-built self-unloader Herbert C. Jackson, to diesel and also specified the COMPAC water lubricated bearing system.

By Professional Mariner Staff