The use of mobile crushing and screening plants in rock processing has arguably been slower to catch on in the United States than in other parts of the world, but it continues to be a growing trend.
“In 1999, we went from using haul trucks to using a track mounted primary horizontal shaft impact crusher at the face,” says Jon Pechacek, quarry manager for Aggregate Industries’ Larson Quarry near Minneapolis. “We then convey the material to a surge pile for the secondary crusher, which is a stationary HSI crusher.”
Pechacek says he believes Larson Quarry may have been the first quarry in the United States to install a tracked crusher. Why did this facility choose to process at the face? “Our fleet of haul trucks was old at the time, and it was a constant battle to keep them up and running,” Pechacek says. “The company looked at the outlay for a new fleet of trucks and decided that a track crusher and conveyors would be cheaper to run.” He adds that, in addition to truck costs, the quarry has realized additional benefits with its use of mobile crushing and conveyors, such as reduced costs in watering and grading haul roads.
“If you can drive the tracked crusher right up to the wall after the blast, then convey that material to the secondary crusher, you’re seeing cost savings from a lot of sides,” agrees Chris Wade, general manager of crushing services for LIMING. “You’ve eliminated the initial capital cost of haul trucks, as well as the ongoing costs for fuel, tires, haul road maintenance, and drivers.”
Wade, who has worked with crushing equipment in both the United States and overseas, says track-mounted plants have always had a natural fit in Europe and Asia’s smaller pits. However, he has also seen track-mounted crushers and screens put to use in smaller quarries and operations in the United States, especially for reducing river rock in dredging operations. “These operations often need someone to help reduce the oversize rock, and they often will build a stockpile and then have a contract crusher come in with a track-mounted jaw to crush the material,” he says.
In Wade’s native Australia, Bryan Rankin is maintenance superintendent, crushing services west, for HWE Mining Pty. Ltd. As one of its services, HWE Mining maintains a large fleet of track-mounted plants available for contract processing services. According to Rankin, while there is a learning curve to operating and maintaining track-mounted equipment, the ability to move independently to the source, rather than having to truck the ore/aggregate to the crusher, means that relocating within the quarry or to another site can be carried out in a matter of hours instead of days — which positively impacts production revenues.
