Coal Age

DEC 2017

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20 December 2017 coal haulers continued hard rock. If the slope is more pronounced or if the roads turn to mud, a number of new calculations are required to determine the point of diminishing returns. First, he said, research reveals the ide- al ramp gradient is below 8%. "If you have a mine with a fairly shallow pit and 4% to 6% ramp grades in your mine, you could probably say bigger is better," he said. As for mud, the ideal rolling resistance was that found at hard rock mines, which in research conducted in Australia averaged between 3.5 and 4.5%, he added. Ebrahimi said that while roads and ramps might typically have limited rolling resistance problem spots, "the ground con- ditions at the face are a completely different issue." The larger the truck, the more the potential problems could arise from "issues with soft ground conditions," he said. If the ramp is too steep and the road too soft, among the first noteworthy prob- lems to arise is that of emissions. "We were starting to get down this path of the rising tier engines, which was supposed to give us better fuel consumption and better control," Joseph said. "Looking at those vehicles that operate on ramps or ground that is really soft with high rolling resistance, like the oil sand companies, we really have struggled to see any im- provement at all. The reason for that is, when the engine has to work hard when the rolling resistance gets higher when the road deterioration is higher, then you not only are having a bad fuel burn, but what goes out of your exhaust is not just NOx, carbon monoxide and carbon dioxide, it is also the hydrocarbon itself. It is the fuel." Emissions and failing to meet legislated standards are among "the first and fore- most things we are being dinged on in the industry by government," Joseph said. Worse, a problem spot causing height- ened rolling resistance repeatedly tra- versed by ultra-class haulers could set off a negative feedback loop. "If you have a higher pressure from your tires, you are going to get more ground deformation. The ground is going to deteriorate more. That means more road maintenance. That means higher rolling resistance," Joseph said. "Higher rolling resistance means longer cycle times, more fuel burn, high- er emissions. This could actually cost us a lot because we've got a larger truck putting down more load on the running surface." Knowing this, miners are forced to plan for it, widening roads that must be constructed with better materials. All that represents additional costs and im- pacts the stripping ratio. "The fundamen- tals never change, but mining methods change," Ebrahimi said. "Larger trucks need wider ramps, which results in shal- lower wall slope angle, increased stripping ratio and increased mining costs." Joseph agreed, saying the bigger trucks require longer ramps, which man- dates the miner "set back the pit walls. The more you have to set back the pit wall, the more you have to cut into it to create what essentially for a much larger mine is a more permanent road system of ramps, the more volume you're taking out." For over 20 years, Classic Motors, Inc. has specialized in the design, manufacture, sales and service of underground mining utility vehicles based on the Dodge Ram truck and Jeep ® J8. From humble beginnings as a typical small-town Dodge/Jeep ® dealership, CMI has grown to become one of the largest providers of underground utility vehicles in North America. CMI, in partnership with Chrysler Group, Cummins, VM Motori, and a large group of vendors spe- cializing in underground mining, has developed an extensive line of vehicles exclusively for the underground mining sector. CMI understands that conditions in an underground mine are extreme. Its vehicles are "hardened" to withstand the abuse any vehicle used underground will receive. However, since its vehicles are based on regular production versions of the Dodge Ram and Jeep ® J8, parts availability and serviceability remain what you would expect from a major manufacturer. CMI offers a wide range of vehicle applications including: • Personnel carriers with a capacity of up to 13 occupants, • Lube/Service trucks to dispense and retrieve a wide variety of liquids, and • General utility vehicles with optional engine driven air compressors. The Jeep ® J8 is Chrysler's military version of the venerable Jeep Wrangler and serves as the front line patrol vehi- cle for various militaries throughout the world. All the vehicles in CMI's product line are equipped with state of the art, MSHA approved diesel engines that offer some of the cleanest emissions available. Transmissions, axles, and suspension systems are designed to work together and proven by millions of miles of use in various applications. "I was lucky to be educated on the unique requirements of an underground utility vehicle by some of the largest coal and hard rock mines in North America" says Joe Betar, Owner of CMI. "My team and I work closely with each of our cus- tomers to ensure that our products meet their needs. More importantly, we bring together the full resources of the Chrys- ler Group and our years of experience in mining to develop service training and support to keep these vehicles operating at peak performance." CMI is dedicated to solving the utility vehicle needs of the underground mining sector. Classic Motors, Inc. COMPANY PROFILE-PAID ADVERTISEMENT

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