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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HAUL TRUCKS 36 E&MJ; • SEPTEMBER 2017 www.e-mj.com those things, the whole question of is big- ger better is still up in the air," Joseph said. "When you are looking at the cost of maintenance, the redundancy in the system, you start to question that and bite your lip, and say maybe it isn't every- thing we've considered if we look at the complete cost of ownership, including the cost of moving all that waste, and the creation and maintenance of these much larger road systems, wider road systems, longer road systems." Ebrahimi said the costs and chal- lenges mandate extensive analysis and planning before committing to deploy- ing an ultra-class hauler. "Mining is so complex that scenarios cannot be copied blindly," he said. The optimal hauler fl eet for one mine may not be the same for another quite similar mine, he said. "Ev- ery single mining project must be evalu- ated independently, under its own condi- tions," he added. The professors diverged on their vision for future demand for ultra-class haulers. Joseph pointed to what he said could be a trend in fl eet management at Western Australian mines as one example of what the future could hold. "These guys have stuck with the 240-ton class, or maybe even the 220-ton class," he said. "They didn't go ultra-class." This has a lot to do with the value of the ore mined. "The actual value of the ore, they don't need to produce as much volume per day and they're still making money." That reality could play out globally, Joseph said. "I think we basically have two types of large mining operation de- veloping," he said. "Those that have high-value ore or fairly shallow mines, the preference is toward the midrange classes, the 240-ton classes, maybe a little smaller." Joseph said this is the case in South Africa, China, Southeast Asia and much of Europe. "You go into Europe, you go into the metal mines of Russia, you go into Kazakhstan and maybe further north from there, you suddenly realize they are concentrating very much on the smaller size trucks," Joseph said. "They're not going with the trucks we know, they're going with their own brands. These operations are specif- ically choosing and sticking with those smaller size classes." Ebrahimi said whatever trend is at play now is likely due strictly to global economics and the metals bear that fol- lowed the peak of what many referred to as a mining super cycle. "In the past 10 years, the mining industry was in state of extreme uncertainty and this prevent- ed the development of new systems," he said. "I see some indication that the min- ing industry is coming back to its boom- ing state. With improved industry condi- tions, we may see more discussion and use of larger equipment." Bigger haulers will continue to have a place in the larger operations fi elding bigger fl eets, he said, but their assign- ments may change based on the value of the ore mined. "I believe the mining industry will move toward larger equip- ment for general earth moving tasks such as waste mining in large open pits," Ebrahimi said. "However, when it comes to ore, we will see a tendency to use smaller equipment. In the future, we will see more mixed fl eet sizes in mines, larger trucks working in waste, smaller trucks working in ore." Doing such could, however, present mine plan and management challenges, Joseph said. "Invariably these generate loading mismatches through needs- based dispatch supplementary fl eet allocations that cross the waste versus ore hauls," he said. "Road design issues develop where larger haulers fi nd their way onto narrower roads." A mixed fl eet also presents unique availability dilem- mas and maintenance cost consider- ations, he said. Bigger haulers mandate more planning, thicker roads and ramps made of better materials, and wider, shallower ramps, the latter of which could impact mine geometry with effects downstream. (Photos: Tim Joseph)