Port Coquitlam, British Columbia-based Harken Towing, which has operations along the Fraser River, is converting its vessels’ tailshaft bearings to Thordon’s RiverTough bearing system following its success aboard the 47.7 foot twin-screw tug Granny Hutch.
Since the first installation in 2015, Harken Towing, which operates a fleet of ten shift tugs, five continuous tugs and nine aluminum water taxis, has installed RiverTough to an additional three tugs and plans to convert its remaining vessels at subsequent drydockings.
Sandy Bourquin, marine account executive at Palmer Johnson Power Systems, Thordon Bearings’ distributor in British Columbia, said the installation has significantly reduced the company’s operational expenditure.
“Many tug owners operating in highly abrasive, silty waterways, such as the Fraser River, find that traditional rubber bearings need to be replaced every two years,” he says. “This means that vessels have to be routinely taken out of service and have their shafts withdrawn, which is a very costly exercise. RiverTough bearings are saving operators a lot of unnecessary expenditure as it is lasting over two times the life of rubber bearings!”
The 6-inch polymer bearings installed on Granny Hutch five years ago have not been replaced and remain in almost perfect condition.
Harken Towing engineer Shawn Davies said: “We checked wear and clearances during a recent drydocking and found the bearings to be in excellent condition. RiverTough has proven itself. The whole system and all the components are in perfect working condition.”
Since that first installation, Harken Towing has converted from rubber bearings to RiverTough tailshaft bearings on its vessels Ken Mackenzie and Harken 6.
Scott Groves, Thordon Bearings’ regional manager–Americas, said: “While there are five companies operating Thordon’s RiverTough along the Fraser River, this is the first clearance data we have received for a vessel operating on this waterway. The feedback from Harken Towing provides clear evidence of RiverTough’s superior wear life in very abrasive water conditions. They routinely outlast rubber bearings by factor of two or more.”
Data from workboats operating the Mississippi River system show typical RiverTough wear rates of 0.075 mm to 0.100 mm (0.0029 inches to 0.0039 inches) in 6,000 to 7.000 hours of annual use.