Stone ground

The bugger the loader, ther fewer passes will be needed to fill a haul truck. This machine will fill the truck in just four runs.
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Gaining stone from a quarry is a hard way of making a living.

Production outputs have to be maintained at a constant level, and an eye must be kept on the international markets so that priority is given to producing the quarry product with the highest demand and therefore value. Obviously, the amount of saleable product must be kept to a maximum while time and money wasted through handling materials twice must be avoided at all costs.

Modern Drills
For decades, drill and blast has been the preferred way of getting rocks out from the face. Some time ago, we spoke to David Matyus, GM of equipment and consuting company Quarry and Mining said “Drilling and blasting is still the high production method.”

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While the technology has remained the same, the size of the drill has increased dramatically. Early methods of drilling into rock were crude, though many times more efficient than hammering away at rock manually – as those of you familiar with the legend of ‘John Henry’ might recall. Modern drilling ‘jumbos’ attach several drills onto one hydraulically-driven mobile plant.

Moving Rocks
Ask most people what the most dangerous aspect of quarrying is the reply invariably is drilling and blasting. In fact, the overwhelming majority of accidents happen on the rocky road between the cliff face and the crusher.

Dozens of huge dumpers thundering down a steep incline, laden with hundreds of tons of rock have the potential for devastating accidents with whatever is coming the other way, no matter how well run the quarry is.

Although things are changing, some quarries still pay scant attention to the safety of the workers. Matyus said “Most of the accidents over here, and there have been some horrendous ones, have involved vehicles.”

He added “There are two extremes, some are very European in outlook and some pay absolutely no regard is paid to safety so you have got small cars driving around in areas where there are enormous trucks.” Obviously, safety begins by removing the small cars from the boulder trails and by better training the truck drivers.

However, new innovations can further improve the run down the hill. While weighing trucks has been the norm for some time, one electronics manufacturer can now supply the region with a device designed especially for articulated dump trucks. The dash-mounted device looks similar to electronic weighing machines that have been around for a while, but has been especially designed for quarrying.

While having trucks carrying the right load is a good start, both safety and efficiency can be made even better, by simply removing the dumpers altogether.

Many modern facilities around the globe have invested in conveyer belt systems instead Although they are expensive and require careful engineering at the point of installation which Matyus explained “A conveyor system is very efficient, For a start, it doesn’t need any power as the weight of the stone pulls it down the hill, so the whole thing is self generating. In fact, it needs brakes to stop the conveyor going too fast”. Large installations can see conveyors hundreds of meters long being constructed, with stone going directly to the primary crusher.