Canada Steamship Lines Inc. owns and operates the largest fleet of self-unloading vessels in the world. One of these vessels is the CSL Assiniboine, which plies the Great Lakes carrying cargos of up to 33,860 tons (28,388 tonnes) of coal, grain or taconite pellets. The ship’s self-unloading system consists of three conveyors belts below the vessel’s holds. These feed a single stern-mounted loop elevator that raises the cargo to a 258-foot (78.6-m) discharge conveyor. This 850 fpm (4.3 m/sec) boom conveyor will unload the ship at rates up to 5,413 tons (5500 tonnes) per hour. But tracking problems on the discharge conveyor threatened unloading efficiency and the life of the belting. To avoid edge damage in the narrow confines of the boom, this 108-inch (2743-mm) wide, ¾-inch (19-mm) thick belt must run in the proper path.
This automatic belt-training device provides immediate and continuous precision alignment of a mistracking belt. The Martin® Tracker™ uses a patented steering system to provide precision adjustments to keep a belt tracking perfectly. The Martin® Tracker™ will work where other belt training devices fail, preventing spillage and extending belt life. To suit application requirements, the Martin® Tracker™ is available in three models: Standard, Heavy Duty, and Extra Heavy-Duty. Selection is based on conveyor speed and belt thickness. On the CSL Assiniboine, an Extra Heavy Duty Martin® Tracker™ Lower Unit was installed to keep the discharge belt centered as it enters the conveyor loading zone.