Due to high humidity, Minera Del Norte Unidad Hercules had problems with carryback on its main 13 m-long (42 ft), 914 mm-wide (36 in.) iron-ore conveyor running at a speed of 1.2 mps (250 fpm). Gritty spillage caused rolling components to seize, resulting in misalignment and safety issues. With a transport capacity of 362 tph (400 stph), operators reported product loss to be around 10% to 30%. Two workers were assigned to clean around the conveyor twice per week, as well as monitor and maintain the system, replacing components when needed. In addition to the lost product and excessive downtime, increased labor and maintenance expenses severely affected the cost of operation.
The Martin Engineering team was asked to analyze the system and offer solutions using the Walk the Belt™ program. Technicians installed a heavy-duty cleaning system utilizing a Martin® Durt Tracker™ primary cleaner and two Martin® SQC2S™ secondary cleaners. With independent blades set on a rigid steel mandrel, the Durt Tracker employs a Twist Tensioner™ to retain a tight seal on the belt while gliding smoothly over the splice. Incorporating individually-cushioned tungsten carbide blades, the SQC2S withstands punishing applications, like high-speed belts and high-tonnage loads with tacky carryback. Together, the units efficiently discharge cargo, offering high equipment life and low maintenance.
Since installation, workers report an operating efficiency of up to 94% based upon product loss. Cleaning has been reduced to only once per month, drastically reducing the cost of labor. "We are very satisfied with the results," said a manager close to the project. "Especially in the reduction of maintenance, which has allowed us to designate manpower to other activities. With less spillage and fewer rolling components locking up on us, we have increased safety for all of the staff working on or around the conveyor." Managers continue working with Martin Engineering on other similar projects to improve efficiency.