Engineering and Mining Journal - Whether the market is copper, gold, nickel, iron ore, lead/zinc, PGM, diamonds or other commodities, E&MJ takes the lead in projecting trends, following development and reporting on the most efficient operating pr
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ROPE SHOVELS els. The hoist brake is designed to stop the dipper from dropping during an uncontrolled event such as a power drop or an emergency stop. The new brake is designed to perform and survive a full speed dynamic brake event with a fully loaded dipper and, as a result, to minimize the risk of an uncontrolled dipper dropping onto a haul truck. Cat's Dynamic Hoist Brake is a drop-in replacement for the standard brake, which was designed to be applied when the hoist motor was not rotating. The new brake offers a number of advantages, including friction material that eliminates burnishing requirements and reduces variations in brake torque, increased thermal capacity, increased product life, mechanical wear indication and simplified, on-machine rebuild procedures. Caterpillar also has developed a Smart Controller, available as an option, to continuously monitor the applied torque, energy input and wear of the Dynamic Hoist Brake. The controller also includes hardware that will apply additional brake torque if necessary via a secondary pneumatic piston. The Smart Controller helps ensure brake torque levels do not drop below specified levels even as a result of temperature extremes, improper maintenance or other abnormalities. The system also monitors brake energy levels to anticipate thermal overload. It can be fitted to all 7495 and 7495HF shovels using the Cat Dynamic Hoist Brake. Cat's Air Filtration System for the big shovels is an improved version of previous Bucyrus systems, incorporating Dynavane filters and other refinements that are claimed to clean the air in electrical rooms 25% better than similarsized systems, and consequently, extend the life of sensitive electrical components. The system, according to Cat, also simplifies filter changing, eliminates dust buildup on the house roof, and employs nanofiber cartridge filters for longer life and higher efficiency. to machine's on-board computer, and permits monitoring, adjustment, reset ting, and modification of electrical parameters. • MIDAS Condition Monitoring—A diagnostic system that helps optimize machine performance by logging and analyzing data on a variety of machine variables. • Accuload—A data analysis system that provides real-time feedback on dipper load. When used with MIDAS, Accuload data can be logged and analyzed. • Bearing Temperature Monitoring—A system that monitors hoist, swing, and crowd bearing temperatures and alerts the operator when temperature problems arise. The four systems can be purchased as a single package or installed individually. Keeping Track of Performance Once a shovel is on-site and commissioned, the key to cost-effective performance and reliability is information—lots of it. Cat offers a "technology package" for shovels that comprises four services: • AccessDirect—An Internet-based interface that facilitates remote access www.e-mj.com JANUARY 2014 • E&MJ; 41