Oil-to-water conversion success for Great Lakes bunkers

The oil-to-water lubricated tailshaft conversion Thordon Bearings carried out last year to the 26,260dwt 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 mammoth 12-month power conversion project completed last year by Fincantieri’s Bay Shipbuilding yard, in Sturgeon Bay, Wisconsin, U.S.A.

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.

Thordon的区域经理Americas，Scott Groves在评论转换的成功时说：“ 2017年9月，海上试验证实，MV John G. Munson消耗的燃料比作为蒸汽船的燃料要少得多，从而大大减少了排放。水润滑螺旋桨轴的排列增加了这些节省的成本，并进一步减轻了尾轴污染的风险。”

由于蒸汽发电厂的使用燃料比可比的柴油发动机多30％到50％，因此船东决定根据美国EPA的轮船还原奖励计划转换芒森的决定已经支付了股息。作为动力，所有者现在可以延长这艘历史悠久的船只的寿命数十年，而不会损害其运营的环境。”

Thordon Bearings’ Director of Marketing and Customer Services, Craig Carter, added: “There are a number of steam-driven bulk carriers that have been earmarked as potential candidates for power conversions, some of which, like the Munson, have already been converted to more energy and environmentally-efficient means of propulsion.
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.

“The conversion of both these vessels illustrates how well-maintained vessels can operate beyond the usual 25 years and be cost-effectively retrofitted to meet today’s more stringent environmental requirements. A 2012 study by the U.S. Maritime Administration found that repowering a laker can achieve 80 per cent of the efficiencies of a new build at 20 per cent the cost,” said Carter.

格罗夫斯补充说：“这些船只的所有者对水润滑布置的表现感到非常满意。Interlake和大湖区都对航运业的变化做出了迅速的反应，并指定了满足美国EPA环境要求的康复。”

He also intimated that Great Lakes Fleet is assessing the performance of COMPAC installed on the Munson with a view to converting more vessels in its fleet to water-lubrication.

Thordon Bearings
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