Modern Quarrying Q3 2019

our tonnages in real time, which is very important for us. We have removed the guesswork out of our planning and loadout processes,” he adds. Having realised these oper- ational gains, the silica mine is planning to have a second system installed on the second front-end loader used to feed material into the processing plant. This will inform the amount of feed material being fed into the plant, versus the amount of material coming out at the four belts. In conclusion, the plant manager believes every quarry should have every front-end loader working on site installed with a load weighing system. “After learning how this system works, my recommendation is that every loader on a quarry should have a scale installed on it. It makes a huge difference,” he concludes. l

printers, network (LAN), CAN-Bus, power supply, as well as radio data transmission via WLAN, GPRS and GPS positioning. “With this system, you always know how much material is being moved – this saves time, lowers costs and improves operations,” says Beukes. The system’s pressure transmitters are connected to the loader’s pressure lines. From there, a cable runs to the front of the cab, where it is connected to the trigger, which measures the weight. A proximity switch is installed on the bucket. “This is to make sure that the bucket is completely rolled backwards when loading and is fully opened forwards when dumping to make sure that every little material is out of the bucket to avoid carrybacks,” explains Beukes, adding that system disallows the operator to continue loading if they are not tilting the bucket enough either backwards or forwards. Every time when the operator starts the loader, the scale asks them to do three warm-up lifts. This happens every time when the machine had been switched off completely. After the warm up stroke, the system compels the operator to reset to a zero reading. Beukes says, with traditional systems, the operator had to do it manually and most of the time they forget, resulting in false loads. “Every time you start a new load, the system also asks you to reset to zero to keep the accuracy within the 1% allowance,” adds Beukes. Additional gains Apart from removing guesswork out of the loadout process, the load weighing system has significantly helped with production planning as well. The second phase of the project entailed the identification of different types of product produced at the operation, and linking each product to specific bunker where it is stockpiled. Each bunker has a name and a different product, so when loading the operator selects the product that he is loading on the system, the location he got it from, the truck number, the customer and order number. By the time the truck gets to the weighbridge, all the information is already loaded onto the system. By the end of the day, the manager has a good grasp of the total number of trucks loaded, the product they loaded and the recipient customers. The system, which is connected to a cloud-based software, also informs the manager on the amount of material left on each product stockpile, allowing him to keep track of the stock count every time, thus informing production planning.

The loader stockpiles mate- rial from the four belts of the processing plant. Each belt has a different size material, namely -1 mm, -500 micron, 2 mm and 4,75 mm. On the scale, the operator selects the product they are stockpiling at a given time, allowing the manager to see the amount of material available on each stockpile. “The system keeps me updated on all fronts. I can see which truck is being loaded, how many tonnes they are loading and how much material is left on the stockpile. We can also do the bucket test to see how many tonnes per hour we are produc- ing from the four different belts,” says the plant manager. “Apart from making sure that trucks are loaded correctly the first time, which has a significant impact on our uptime, the load weighing system also informs our production planning. We can see

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QUARTER 3 - 2019 MODERN QUARRYING