Heavy Lifting: Find the right big equipment for aggregate-handling jobs
Written by Bill Law
Is your quarry equipment pulling its weight?
It should. Demand for rocks and sand and their aggregates is still growing, despite a cooling in North America’s construction industry, as global projects to build homes, hospitals, factories, bridges and roads are growing at record rates. The tough demands of a quarry require high-quality, safe machines, and there are many different steps to the work processes, and each has to be studied to get a total market understanding.
“When a customer identifies a site for quarrying, they first have to clear the land,” explains Karl-Gunnar Eriksson, Volvo’s product and application engineer for loaders. “Often the land will be covered in trees, so we need to provide special excavators with attachments for logs. Land stripping is the next stage, where haulers are needed to get rid of all the surface material - the overburden.”
Step 3 is drilling and blasting to break into the rock, and although Volvo does not supply machinery for this process, its large range of wheel loaders are utilized at the next stage, face loading. The rock is extracted from the quarry face and transported to the crusher. There are times when the blasting process fails to reduce the rock to blocks small enough for transportation, in which case an excavator with a hydraulic hammer can be used to reduce the size of the blocks further.
At each stage, the customer has to choose the best machine for a particular site and, equally important, fit it out with the right attachments. With companies supplying an array of machinery, attachments, options and services, the choice can become confusing for a customer trying to choose the right machine configuration for their own particular needs. “This is why the company is investing so much time and effort into segmentation,” Eriksson says of Volvo. “To make the choice easy for customers.”
After the face loading stage, the blasted rocks have to be transported from the quarry face to a crusher to be turned into aggregate. If the crusher is fewer than 150 metres away, it is economical to use the wheel loader to transport the material. For longer distances, trucks and articulated haulers are recommended. When the crushing process is completed, wheel loaders and articulated haulers are needed once again to load the aggregate onto trucks for distribution to the end user or to be stock piled.
Heavy equipment constantly moves about the quarry site, and the heavy loads can play havoc with ground conditions, so motor graders and backhoe loaders are required for haul road maintenance. “If a site owner does not invest in maintenance, they will run into a hefty repair bill,” Eriksson says.
The same type of segmentation project is also ongoing for industrial material handling, dealing with what happens to aggregates after they are transported from quarries to mixing plants, where asphalt, concrete and mortar, etc., are produced. Industrial materials take all sorts of forms, such as asphalt, concrete, steel, chemicals, salt and fertilizer, demanding different wheel loaders, excavators, backhoe loaders and attachments.
Bill Law is director of global external communications at Volvo Construction Equipment, which they say supplies around 12 percent of the quarries and aggregates sector’s equipment. For more information, visit www.volvo.com.
